Q&A with Mark Waldrep of AIX Records and iTrax.com Part 1 of 3

Dr. Mark Waldrep

I originally corresponded with Dr. Mark Waldrep, founder, president and CEO of AIX Records and iTrax.com, back in September of 2011 when he agreed to participate in our first Industry Voice article, "The Future of Computer Audio". We've been in touch a few times since mainly talking about the appropriate time for Mark to discuss his views on HD downloads in-depth. That time is now.

We've split this Q&A into three parts; Part 1 which you'll read all about in a second or two, Part 2 which dives into recommended provenance requirements for HD downloads, and Part 3 in which we'll talk more about the past, present and future of iTrax.com.

As you'll notice, Mark Waldrep has taken a more holistic approach to this Q&A and worked my Qs into his larger context. I'd like to thank Mark, as well as all of our other Q&A guests, for their time and generosity.

Understanding High Definition Audio: Facts and Fiction

"It's good to know there are still some labels (AIX Records) left dedicated to making high quality surround recordings. I applaud you for educating people about what is and isn't HD (analog tape/vinyl being an example that isn't HD)."

Dr. Sean E. Olive, Director of Acoustic Research/Corporate R&D, Harman International

"As many of you might already know, I've been a strong advocate for high definition audio, surround mixes and identifying the 'provenance' of music recordings for a long time."

I started the audiophile label AIX Records in 2000 and seven years later the HD-Audio download site iTrax.com but I've been an audio enthusiast and engineer for almost 40 years. I've been reading the articles and comments of Michael Lavorgna and others on the AudioStream web site for a while now. Following some of the recent interviews, Q&A sessions and articles, I thought it might be a good time to reach out to Michael and offer my two cents on a range of topics that may be interesting to the site's readers. As many of you might already know, I've been a strong advocate for high definition audio, surround mixes and identifying the "provenance" of music recordings for a long time.

In one of those cosmic coincidences, it seems Michael was thinking the same thing. We talked on the phone and agreed that I should author a piece about a range of topics including the recording process, high definition audio, recording provenance and the future of high definition downloads.

AIX Records Studio

It's not a secret that audio professionals, music fans and audiophiles in particular are an impassioned group when talking about all things musical. And they're not shy about expressing their opinions on their own promotional brochures and commercial sites and forums like AudioStream. I include myself in that group. However, it's always interesting to me how a reasonable debate often breaks down into simplistic statements based on anecdotes, emotions and religious "blind faith" fervor rather than facts and substantiated observations. Don't get me wrong. You can believe whatever you want but understand that the act of believing doesn't make something true. It might just be a "fact" for you.

I should state right at the start that my goal in writing this piece is not to say that audio professionals and music fans do not have the right to record, listen and enjoy music played back in any format, through any number of speakers or even headphones/ear buds. However, what is often forgotten in this debate is that there are as many different goals for music producers and engineers as there are styles of music.

"Somebody once told me that the ultimate goal for an audio engineer is to recreate a musical event…a sort of sonic documentary. That's fiction."

Somebody once told me that the ultimate goal for an audio engineer is to recreate a musical event…a sort of sonic documentary. That's fiction. It might be true for some engineers and producers but it's not universally true. The Beatles or Peter Gabriel didn't issue recordings that sound like live performances. With the guidance of other creative individuals they produced musical works that are sonic masterpieces crafted from lots of individual "musical" components. Producing music is a very personal and individual activity requiring the collaboration of songwriters, musicians, engineers and producers. Some tailor their records to maximize sales and appeal to a particular market channel and others produce recordings with other goals in mind. We'll examine some of them later.

Formats are another aspect of recording that draws ardent supporters to various camps. Go ahead and like what you like. It's a matter of personal taste. I came back from the Rocky Mountain Audio Fest a couple of years ago with a brochure exclaiming "Three Universal Truths" about analog tape and machines. They were neither true nor universal but just another example of marketing parading as facts. The author used of lots of large numbers in comparing the number of magnetic domains at a particular tape speed vs. the number of digital samples per second. The whole brochure was complete fiction.

"But please understand that saying 'intense musical space and realism' can ONLY be produced by analog tape is once again fiction."

Now, if you're a believer in analog tape and believe that "intense musical space and realism" can only be produced by analog tape, as one proponent expressed on their web site, then fine. You can believe that and purchase the equipment and tapes necessary to live in that world. I own a stereo NAGRA IV-S and an AMPEX 440C two-channel tape machine and I know exactly what they can and cannot do. In fact, AIX Records will probably make our HD-Audio stereo mixes available as straight copies to analog tape using my Nagra for anyone that wants that sound (stay tuned). But please understand that saying "intense musical space and realism" can ONLY be produced by analog tape is once again fiction.

Nagra IV-S Frequency Response

I've stopped discussing things that are based on emotion and opinion in the world of audio recording and reproduction. I respect that others can and often do have different experiences than I do. But please keep an open mind (and ears). Just last March at the AXPONA show in Jacksonville, the guys in the ballroom room next to me were all about two-channels, turntables, vinyl, tubes and open back speakers. During the set up day, one of the guys in the room said to me, "digital sound is cold, unemotional, lifeless and sterile". I responded by asking him to spend a few moments in my high definition digital, 5.1 surround room listening to some of my surround recordings. I was pleased that he did come by (in fact multiple times) and liked what he heard.

"Asserting that PCM digital is 'sterile or lacks warmth' is also fiction."

When we parted company on the last day of the show he told me, "You won me over Mark. The experience in your room was fabulous! You've changed my mind." And I can tell you that I enjoyed his room as well. We both preferred our own systems, but he went away with a newfound respect for multichannel, PCM HD-Audio (with 3D video as well…but that's another article). Asserting that PCM digital is "sterile or lacks warmth" is also fiction.

Q&A with Mark Waldrep

Can you give the readers a brief overview of your background?

I've been passionate about music since my earliest memories. As a kindergarten student at Pembroke Elementary School in Birmingham, Michigan, I can remember refusing to go outside for recess because I was so enthralled at the sound of the classroom's industrial monaural record player reproducing Burl Ives' voice and guitar as he sang children's songs on a Decca LP (a record that I still have as I approach 60 years of life!). As a teenager, I learned to play the guitar and spent hours practicing and playing guitar with my musically inclined friends. In college, I abandoned architecture at the University of Michigan because my new Martin D-18 guitar became the focus of my life and occupied virtually every waking hour. I moved to California to be a rock star but realized after having lunch with Larry Carlton (a very famous guitar player that I just called on the phone) and sitting in on a session that my future was going to be on the other side of the glass.

"I was the first doctoral student at UCLA to receive a Ph.D. in electro-acoustic music."

My obsession with music continued through college with undergraduate and graduate degrees in music from Cal State Northridge, Cal Arts and UCLA. At a high school reunion a few years back, my classmates were very surprised to learn that I had received my Ph.D. in music composition. I was the first doctoral student at UCLA to receive a Ph.D. in electro-acoustic music. I was a science and math guy when they knew me back in high school. My interest in technology didn't completely disappear; I also received my MS in Computer Science a few years later.

Thanks to a father, who was a HAM radio operator, I learned electronics and later I actually made my living building and repairing audio equipment at the California State Univeristy at Northridge. I actually built my first electric guitar and amplifier as kits from HeathKit Electronics. If it is has a switch on it, I want to know what makes it tick. During my graduate studies at the California Institute of the Arts, my close friend and fellow computer music composer Peter Otto and I used to do all of the sound reinforcement for the annual Contemporary Music Festival. We worked with some of the most important composers from around the world including Milton Babbitt, Mario Davidovsky, Iannis Xenakis, Steve Reich and Morton Feldman. We also did the sound for the 1984 Olympics Arts Festival.

After college, I went to work for Moma Jo's recording studio in North Hollywood, California thanks to a recommendation from one of my teachers Dale Manquen (the designer of the 3M 56 16-track 2" recorder…a machine that I ultimately owned in my first studio). I worked with lots of different artists including Ambrosia and Randy Crawford during my time at the studio. I used to stay there through the night setting up microphones and learning signal flow and honing my recording technique with some very patient musician friends. I spent a year doing production sound for film and television with the late Mike Denecke (aka "Father Time"), inventor of the ubiquitous timecode slate. Mike was an amazing mentor and taught me about radio mics, using a boom, Nagra machines and sync sound.

"The marriage of music, audio and technology, especially digital technology, has kept me intrigued, motivated and obsessed like nothing else."

I've traveled to Haiti to record Voodoo musicians, to Romania to capture the Georges Enescu Philharmonic playing Bach and Beethoven and to the rain forests of Costa Rica to record the sounds of howler monkeys and exotic birds for a relaxation CD. The marriage of music, audio and technology, especially digital technology, has kept me intrigued, motivated and obsessed like nothing else.

Mark Waldrep in the studio c.1993

How did you get involved in High Definition Audio and AIX?

I've been recording and releasing high definition, surround music products since I started AIX Records in 2000. That was when Panasonic and a bunch of other consumer electronics manufacturers introduced the DVD-Audio format, which was supposed to be the replacement for the aging compact disc. As an audio engineer and the owner of a fledgling multimedia production, I was very interested in combining the best parts of the new DVD-Video format (widescreen video and surround sound) with the potential fidelity improvements that the new audio-focused DVD discs promised. The opportunity to elevate the quality of music reproduction through better fidelity and surround mixes was very attractive.

It seemed that the major labels weren't interested in recording and releasing new productions in the new DVD-Audio format. They were all about resurrecting the blockbuster albums from their archives and repurposing them for delivery in the "enhanced resolution" format of DVD-Audio and with 5.1 surround remixes. It was great to hear 5.1 DVD-Audio releases from Fleetwood Mac, The Eagles, The Doors, Steely Dan and Neil Young but I was hungry for new high definition productions that would show off the increased dynamic range and frequency response of the format. They stuck to their archives in the search for the "killer album" in the new format.

"I refer to it as a 'Field of Dreams' approach because I wanted to do something without any compromises and see if music lovers could hear and appreciate the difference."

But I owned a state-of-the-art studio and had all of the equipment capable of recording and producing music in high definition. So I decided to start a record company that would produce NEW music projects with HD capable equipment. My DVD-Audio/Video products feature multiple mixes ("Stage" and "Audience" perspectives), lots of bonus videos and dramatically enhanced fidelity. They were conceived and produced as ultimate fidelity and surround music products. And many of them were recognized as exceptional audio products (we won multiple awards at the first Surround Music Awards including "Best of Show"). I refer to it as a "Field of Dreams" approach because I wanted to do something without any compromises and see if music lovers could hear and appreciate the difference. I built it and I wanted to see if they would come. Luckily, they did.

What are your recording methods and how do they differ from others?

Our methodology combines the Windham Hill sensibility of very close stereo miking (we place lots of stereo pairs of microphones just inches from the sound sources) with the purist approach often associated with classical or jazz recordings. In other words, AIX Records brings all of the musicians/singers into an acoustically rich chamber music auditorium and records the entire ensemble as if it was a live performance but without an audience. What you get at the end of a day of recording is an entire albums of tracks AND raw video of the musicians making music. And we do this using a state-of-the-art HD digital audio workstation (capable of 96 kHz/24-bit PCM…there is absolutely no benefit from moving to 192 kHz) AND high definition video equipment. During postproduction we don't process the timbre or dynamics or use artificial reverberation. And we completely avoid "mastering" our products. I spent 13 years as a mastering engineer and find the process unnecessary and actually detrimental to the natural sound that I'm after. The only reason for mastering a record is to make it fit into the standard radio promotion model.

"Paul [Rogers of Bad Company] wanted it to feel dynamic and real, but the label (the money in the picture) got their way. I gave up mastering not long after that."

I mastered Bad Company's "Merchants of Cool" with Paul Rogers back in the 1990s. Contrary to what others have stated, the artist doesn't usually get what they want (I don't think most musicians would be happy with the "mastered" version of their artistry). I was told by the label 5 times to suck out more of the dynamics of the tracks. Paul wanted it to feel dynamic and real, but the label (the money in the picture) got their way. I gave up mastering not long after that.

Other engineers and producers might say they can't imagine listening to a piano or guitar from mics located very close to the sound source. But I think they forget that the individual instrument or voice captured from that position is delivered via a loudspeaker in the consumer's living room. The reproduction of the sound for the listener is as if the playback speaker stands in place of the soundboard of the guitar or trumpet of the actual instrument. The result is the instrumentalist or singer is "sonically" placed 8-10 feet from the listener. The sound of a pair of microphones 15 feet from the performers coupled with another 8 feet in the listening environment produces a very unfocused and distant sound that I find impersonal and uninteresting. However, others like that more distant sound.

5.1 set up with virtual instruments

I know my friend Morten Lindberg of 2L, who has garnered a bunch of Grammy nominations, uses this method when he records jazz and classical ensembles in churches or other acoustically rich spaces in Norway. It seems to be working for 2L and Morten but the feedback I get from the artists on my label, reviewers and customers tells me that our methodology is producing compelling audio as well (and with individual mikes I get to mix in "audience" and "stage" perspectives).

"…the multichannel audio, emanating from five B&W 801 loudspeakers, is quite simply the most realistic and involving instance of recorded sound I can recall, from any source format. Mark Waldrep knows what he’s doing."

Andrew Quint, Senior Editor, The Absolute Sound Magazine

The traditional method of making records involves many individual sessions in an acoustically "dead" room, months of overdubbing individual parts, sessions where the parts are moved into perfect time and vocals are "auto-tuned", weeks of mixing and finally mastering for a particular delivery format. This is the commercial model and it's what I teach at a university here in Southern California. There are lots of targets in the music industry and all of them serve a different market segment. This is not a one size fits all industry.

How do you define High Definition or High-Resolution Audio?

First off, I choose to call it HD-Audio to parallel the well-known HD-Video term. It seems like a simple question that most interested individuals would agree on but in reality there is wide disagreement among audiophiles, audio engineers, equipment manufacturers and marketing departments. Here's my definition.

"High Definition audio is sound recorded using equipment that matches or exceeds the capabilities of human hearing in terms of dynamic range, frequency response and spectral accuracy."
At the core of this definition is the notion that recorded and reproduced sound must achieve the fidelity of real world or "live" music as perceived by human beings. Audiologists will tell you that you can hear frequencies between roughly 20 Hz and 20 kHz (depending on your age) and can handle sound pressure levels from the quietest environments (25 dB SPL) to something approaching 135 dB SPL (this is painfully loud and exposure for any length of time will do permanent damage to your ears!). But I think you can appreciate that our ears are extremely capable organs. Hearing is our most capable sense in terms of its range of input source.

"HD-Audio can capture everything that is produced during a music performance including the extended frequency response and dynamic range."

However, this doesn't mean that instruments can't and don't produce sounds that exceed these human limitations. If you measure the frequencies that emanate from a trumpet with a Harmon mute or a crash cymbal they routinely extend to 45 kHz and beyond. Loudness transients from a rim shot or the dynamic range of a timpani from pianissimo (pp) to a triple sforzando strike with a hard mallet can easily exceed 80-90 dB. HD-Audio can capture everything that is produced during a music performance including the extended frequency response and dynamic range.

This is where the disagreements start. I've read articles by prominent journalists that describe analog tape as the ultimate recording and reproduction system. I even brought my aging Ampex 440C down from the attic at the studio in the hopes of selling it to a fan of analog tape. Obviously, there's a resurgence of interest in analog tape as an audiophile format. The Tape Project is selling a single album for hundreds of dollars to a sizeable customer list. I don't argue or get upset with anyone when it comes to his or her personal preferences. If someone likes the tonal characteristics of analog tape or vinyl or an MP3 file, then so be it, to each his or her own. But don't try to tell me that 60 dB (which is the signal to noise ratio of a good analog tape deck and is the equivalent of 12 bits in a PCM digital system) of dynamic range captures and delivers the fidelity of a symphony orchestra, a singer/songwriter or an energetic jazz ensemble. It can't and it doesn't. Analog tape and the formats further down the line from an analog master (such as vinyl) are standard definition formats plain and simple. You and many others (including professional writers and audio engineers) may prefer the "sonics" of tape or vinyl but that doesn't elevate them to HD status.

Nagra IV-S Signal-to-Noise Specs

When someone says a particular track is "master tape" quality, what do they mean?

They mean that the original master tape, whatever its original fidelity level, has been played back on a calibrated analog tape deck, captured as a digital file through a high quality A to D converter and made available in various digital formats through the internet or on data discs (most of the time compressed in a lossy format like MP3). The ability to get access to the fidelity of the original "studio master" for our music enjoyment at home is a tremendous advancement. But the fidelity of an original "master tape" is never going to be better than the technology that was used to produce it at the time of the original sessions. Putting a standard definition "master tape" in a high definition digital container (96/24) can guarantee that you won't lose anything during the conversion but it doesn't elevate the fidelity of the original to the dynamic and frequency ranges of a new high definition production. There is a huge difference!

"The simple truth is that not everything that lights up the 88.2/96 | 176.4/192 kHz sample rate and 24-bit word length indicators on your hardware possesses the right 'sonic' stuff to be called 'HD'."

In this age of portable digital music players, so-called "high definition" downloads and home music servers, the confusion about fidelity gets twisted by opportunists and marketing types looking to portray everything from the standard definition past as an "HD" track. The simple truth is that not everything that lights up the 88.2/96 | 176.4/192 kHz sample rate and 24-bit word length indicators on your hardware possesses the right "sonic" stuff to be called "HD". This is why it is critical to know the recording "provenance" of a particular download. Avid music fans can get everything a "master tape" has to offer in digital form but there's the original fidelity of the "master tape" and then there's the digital delivery container we can purchase.

What's missing in the discussion about this emerging market is some honesty and transparency with regards to the production chain that a particular track undergoes from the original production to the ultimate delivery format. What some purveyors of "HD" tracks would have you believe is that the specifications of the digital delivery bucket is the single most important factor in establishing the quality of your listening experience. It is not! What needs to be instituted in this move to music "files" is a corresponding description of the original production and the potential fidelity that could have been achieved at that time. That is what you are purchasing when you download a track from a digital music retailer. I have downloaded an ABKCO era Rolling Stones album at 88.2 kHz/24-bits and was able to determine that the fidelity of the file was indistinguishable from the compact disc version…and I spent 20 dollars thinking that I was getting an "HD" track (Actually, I knew better but most customers don't) and ended up with no greater fidelity than what was already available.

"If a website is charging a premium for high-resolution downloads, then those files need to contain information beyond that which can be offered on CD. If they do not, you should ask for your money back."

S. Andrea Sundaram, Soundstage

As someone that produces only REAL HD-Audio tracks on my label AIX Records AND distributes REAL HD-Audio downloads at iTrax.com, I'm astonished at the lack of information by audio writers, technical professionals and average consumers when it comes to what is and what isn't a high definition audio recording. Even Neil Young, a staunch crusader for better quality music formats, has it wrong. He records on analog tape and then masters to digital for distribution. Sure, he should be able to give his fans the fidelity that he prefers but it's not high definition because the analog tape machine established the ultimate fidelity of his delivered tracks no matter what happens later in the production chain.

"What I am hoping for is that music lovers will add another way of experiencing music to their palette of playback options."

I'm not saying that everyone should give up his or her vinyl, tubes and embrace 5.1 surround delivery. What I am hoping for is that music lovers will add another way of experiencing music to their palette of playback options. One you've heard the increased dynamics and extended frequency response in a "stage" POV mix, I believe you'll be "blown away".


Wow! Words do not express adequately what I heard and experienced yesterday. What you shared with us has forever altered my perception of how music should sound and what defines a truly great recording. You have also inalterably shifted my expectation of how music should be recorded and played back. Thank you! And please don't ever stop doing what you do!"

James Collard, Customer

Regor Ladan's picture

Very interesting read. Of course much of this is "informed" opinion.

I agree Digital is cold and sterile is pure fiction..and this myth is propogated by many audio journalists.

Totally agree that mastering is uncessary in most cases. The ones that tell you music must be professionally mastered are mastering engineers who want to buy another Masterati.

Close miking is the most desirable method of recording in many (but not all) cases.

Many music consumers over 35 consume a huge proportion of their music that was recorded to analog tape.

We definitely want the best archival quality or "bucket' for these tapes, whether it be DSD, 96 Khz/24 bit or 192 Khz.

I don't care if you call it High Resolution or High Definition, but it is clearly higher quality than 44.1/16.

I agree there IS a distinction between a native high resolution recording and an a digital archive of a recording done in an analog or early digital format.

5.1 sound has been rejected by most listeners, and for good reason. This goes back to my previous post that most over 35 consumer music recording and mixed in two channel audio.

The genteleman is absolutely correct that the use of "HD" as a marketing term by various download sites is laugable.

Lastly, not ALL artists at the mercy of record company executives. Just ask U2, who own their master tapes, and remastered the entire early catalog themselves.

No benefit to 192 Khz?

firedog55's picture

I agree that the ABKCO Stones recordings in "hi-res" aren't true HD. But my 24/88 versions clearly sound better than other versions I have. I'm pretty happy that someone got everything possible out of the master tape and let me have a copy of something as close to the master tape as I'm ever going to get.

Michael Lavorgna's picture

While I can also see Mark Waldrep's point regarding the importance of knowing what we're buying and the provenance of HD downloads, I’m not so sure I agree with the notion that an analog master cannot provide a HD version.

Regor Ladan's picture

Agree with you Firedog55-

Mr. Waldrep says: I have downloaded an ABKCO era Rolling Stones album at 88.2 kHz/24-bits and was able to determine that the fidelity of the file was indistinguishable from the compact disc version…and I spent 20 dollars thinking that I was getting an "HD" track (Actually, I knew better but most customers don't) and ended up with no greater fidelity than what was already available.

He was "able to determine" the downloads are no better than the CDs how? In my own personal comparisons, some of the downloads are superior to the corresponding CDs. Specifically, more analog like. While I agree they are not High Definition, they may be High(er) Resolution than CD. We all know they are downsampled PCM rips of the commercially released SACD discs. Those SACD layers are excellent. A case of converting his own beliefs to "fact"?

Michael Lavorgna's picture

I'm not sure if Mark Waldrep has time to respond to comments but I will let him know there are some questions.

labjr's picture

Another interesting Q&A session.

I somewhat agree with the assessment of the Stones ABKCO HD Tracks downloads. A friend bought a couple of the downloads and we compared. I thought they sounded slightly better than any of the CDs which I've heard, but definitely not very involving. However, we didn't do do a controlled experiment.

A while back I read a Bob Ludwig interview. If I recall he did the transfers to DSD at least 10 years ago. I guess these same transfers were converted to PCM a couple years ago using Weiss Saracon conversion software. So it's a cross-conversion from another digital format. Why not start with the original master tapes using newer converters?

Bob Ludwig also claimed there was no discernible difference between the master tapes and the DSD transfers. Did the analog tapes sound that bad? And there's something about the sound of SACD that I've never liked. Is the the part I don't like about DSD transferred to PCM. And what other problems are caused transferring DSD to PCM?

Regor Ladan's picture

CORRECTION: Bob Ludwig did NOT do the DSD transfers. He mastered off the DSD files he was sent.

On a personal note, I really don't know why it has become the party line to bash the Stones ABKCO recordings. They are very much in line with all the other classic 60s recordings from the Animals, Jefferson Airplane, Tull, Hendirx, The Doors, the Yardbirds, Cream etc. They are gritty, raunchy, rock n roll records. I love the way they sound, and they very much reflect the time in which they were recorded.

The Beatles were a bit unusual in that they recorded virtually every one of their songs in the same studio, with the same engineers, and with a very gifted producers. Unlike the common practice of the time, they never recorded on the road. Oh, and they had a virtually unlimited budget.

Michael Lavorgna's picture

From the HDtracks website:

For this HD Tracks release, the Bob Ludwig mastered DSD files were converted to both 176.4kHz and 88.2kHz high resolution PCM with Weiss Saracon conversion software.

And from an interview with Bob Ludwig from Pro Audio Review:

Original UK and US analog mix-session masters were painstakingly transferred to Direct Stream Digital by Teri Landi of ABKCO and Steve Rosenthal of The Magic Shop in the US, with mastering engineer Jon Astley providing masters from the Decca UK vaults.

Bob Ludwig carefully referenced previously released pressings of the material as he mastered the catalog, first to DSD (for SACD layer) and then down-sampled to create the PCM master (for standard CD layer).

From the same interview:

What was your general process in mastering the Stones project?
I would put up a song and EQ it way I thought it should be. Then we  checked it against the original London and Decca pressings as originally intended and approved. We also checked the singles if the original was  mono. Next, the 1986 CD would be checked, as this was the source for probably 90% of the people who know these songs. Often we had the originals beat right away, but sometimes there was something magical about the vinyl pressing that took a lot of effort to duplicate, and then better.

labjr's picture

 "Bob Ludwig did NOT do the DSD transfers. He mastered off the DSD files he was sent."

If he didn't do the transfers then what was left to do in the mastering process after he got files?

I think a lot of the problem with sound quality is all the transfers, re-transfers, re-conversion and manipulation of the material which they call mastering.

bdiament's picture

There seems to be an assumption, which I've seen elsewhere, that if no knob twiddling is involved, there is no need for mastering - essentially equating mastering with alteration of the original program material.  This is, in my view, misguided.

The fact is *everything* a listener can hear at home, on CD, DVD, SACD or vinyl, has been mastered.  In order to mass produce discs, whether polycarbonate or vinyl, the program material must at the very least, be formatted for the target medium.  This is one of the functions of mastering.  

Further, every monolithic A-D converter (of which I'm aware) will exhibit lower distortion if the maximum peak levels do not exceed approximately -6 dBFS.  Final levels should be adjusted in the mastering room.  So even if the target is a set of .aif or .wav files to be played back via a computer music server, mastering is where it is all brought together.

As an aside, I recall one mastering session where I was listening to the client's mixes and mentioned that the one we were listening to at that moment sounded to me like it was fine as is and that I did not feel it required any EQ, as we determined the previous song required.  The client's response was "So you're not going to master that one?"

I explained that the decision to *not* apply EQ or another process is as valid a mastering decision as the decision to add x dB at x Hz and that if the song was to be included on the CD, it would indeed be mastered.

In sum, if you're listening to it at home, the likelihood that it was mastered is better than excellent.

Best regards,

Dr. AIX's picture

I've been quite busy in the studio mixing and preparing audio for our next round of releases. The Free Flight jazz/classical project is so much fun and absolutely full of dynamics. There's pianississimo to full out piccolo at the top of its range! Coming in a couple weeks.

Barry's correct that virtually all the audio that you are likely to experience has been through a "mastering" process. But the amount of sonic modification applied during the final stage in the preparation of an album or single track is what's important. I spent a lot of my life making records sound "punchier" and "more even" as a mastering engineer. I've even added noise to more than a few tracks to make them consistent with the other noisier tracks on a compilation CD.

Mastering is essentially comprised of loading the material (sometimes using A to D conversion or other times digital transfers), sequencing the tunes and adding fades, equalization, dynamics processing, adding PQ and metadata and then transferring the album out to the delivery format.

When I say that I don't master any of our AIX Records releases, I mean that I don't modify the timbre or dynamics in any way (I don't do it during the mixing stage either). My mastering consists of sequencing the tunes with the appropriate gaps, putting fades on the heads or tails and transferring them out digitally (everything we do in the digital domain after the initial conversion at 96/24).

When I hear big time mastering engineers on a panel say that they feel the need to "even out" a bass line or compress the errant drum dynamic, it bothers me. But then again I am interested in reproducing the original sound of the performance and this is not what Bob Ludwig or others are paid to do. They are challenged to maximize the sales potential of a particular album by making the record consistent with the industry/label requirements.

As for the Stones, Beatles and other classic recordings...I agree that they can sound great. I have copies of the 4-track Sgt Peppers recording and analyzed it in terms of dynamic range and frequency response...not great compared to current possibilities but who cares? If it sounds great then it is a wonderful musical production. But it's not a high definition track by my definition. It's important for consumers and music fans to understand the differences. It can only help clarify the diversity of music formats and qualities that we are able to chose among.

I'm optimistic that the future of music delivery through networks will allow everyone to have it their way...highly compressed and "radio friendly" or "purist" audiophile style.

One of my favorite records of the past couple of years was the Beatle "Love" DVD-Audio disc in full surround sound. Amazing project in so many ways. I've listened to it in my 5.1 room many times. It's a masterpiece of mixing and blending but it is decidedly not high definition...but I don't care.

But when you get a chance to hear a real HD-Audio track in full 5.1 surround in a great room through great equipment, you'll immediately know that there's something else happening. Whenever I demo at trade shows or in my studio for newbies to surround music, the overwhelming majority (90%) say the immersive surround sound is, "hands down" more compelling than the standard stereo version. The problem is the "stereophile" press has rejected surround music delivery out of hand. That's too bad for those seeking a really amazing reproduction of music on a personal level.

Regor Ladan's picture

The good Dr!

Thanks for your post. I think what gets confusing for many is separating what I call the physical part of mastering...the sequencing, fades, coding, metadata etc...from the so called "artistic" part of mastering..the EQ, compression etc. Personally, I think the rise of "celeberity" mastering engineers was where many things started to go wrong. You then had a relatively small group of individuals deciding how records would sound. Then of course when one of those celebrity mastering "gurus" had a hit, everyone else would start to emulate the sound of that record, which leads to a mind numbing sameness that appeared especially in rock and pop records.

If I was producing records, I would get the material to the mastering engineer, if I even decided to hire one, in the most complete form possible..and that includes having it sound about 95% or more the way I want so that it does not have to be messed with beyond the physical part, unless issues arise that a third set of ears happen to bring to light. In other words, the material would leave the studio in as close to release form as can be.

BTW, it is my own personal opinion that it is not just the "stereophile" press that has rejected surround sound...consumers (audiophiles) have as well. I have heard 250K 5.1 set ups and it just does not replicate the way i hear live music. Again, IMHO.

Thanks again for your contributions to this site!

Dr. AIX's picture

I don't think consumers have been given the opportunity to hear surround mixes the way that I prepare them. As I said, I've rarely had anyone (including very staunch two-channel advocates) go away from one of my demos preferring stereo. Here's a message I received a couple of years ago from one convert,

"I thought I’d write a couple comments about the AIX demo we recently had at a BAAS event, since it turned out to be a good eye/ear opener for me. I attended the morning session, and got there early enough to sit down and acclimate to the sounds in the multi-channel room. First thing that came to mind was, “why are the drums coming from the right rear of the room?” Several decades of listening to two-channel music gave me enough background to KNOW that this was amiss and contrary to “how it should be.”

      Eventually, the meet started and Mark Waldrep gave his presentation which included his vision of sound recording, reproduction, and appreciation. I could appreciate his points that he made with respect to instrument placement in a multi-channel recording, and his whole ideal of the sound he strove to achieve in the final product he produced. I really liked his philosophy of obtaining the purest recording of an instrument, or voice, possible, and then not mucking with it further. Nothing in what Mark said indicated that he’d think it is a good idea to convert back to analog, record it to tape, then play it back from tape and redigitize. Dumbing down is dumbing down, and Mark just doesn’t entertain such stunts.

      Later, we swapped rooms, and I got to enjoy many two-channel recordings of exceptional quality in a presentation that I was fully comfortable with.

      Nice thing from this event was that I got to walk out of there with a free sampler of AIX releases with DVD-A on one side and DVD-V on the other. Not having a DVD-A player, the choice of sides to play was pretty easy. So, I put this disc into my player last weekend to give it a fair shake. Knowing that both the “stage” and “audience” perspectives were available for each song, I opt to hear the “stage” mix for all of my listening. Again, I notice right off that it is a bit weird having the drums in the right rear of the room, but after a while I also notice that this mix is very easy to listen to and identify individual instruments in the soundfield. I stuck with it and listened to most of the extensive list of samples provided on this disc. At the second to last song, I decided to switch over to the “audience” mix. Whoa! After becoming used to the “stage” mix, the “audience” mix literally folded into a flat plane along the wall that I have my front speakers on. Sure, this was now a very traditional mix, and I never realized how flat and lifeless it is. It was like looking at a picture hanging on the wall instead of literally experiencing the music around me. Even more interesting, to me, is that in the “audience” mix there was still significant energy in the rear speakers, but it was a flat presentation in front of me. Going back to “stage” mix all of the instruments opened up, got plenty of space around them and lost a lot of congested feeling in the sound.

      When I first heard the “stage” mix, I was unable to notice the clarity of the instrumentation itself, because I was too caught up with the uneasy feeling of the different mix. After I took the time to give this new (to me) mixing style a chance, I found I may actually like it a lot. It really seemed to add a new level to the appreciation of music that I haven’t experienced yet."

This has been the reaction to virtually all of my demo sessions.

If you haven't experienced one of my "stage" mixes, you haven't really heard what I'm talking about.

Back to mixing Wallace Roney and Brand New Opry Volume 2 for release in September. Free Flight and Mark Chesnutt just went to the replicator this morning.

Regor Ladan's picture

Hey Mark: Trust me, I am not dismissing your "stage mix" approach or multichannel mixes at all. I have heard some impressive set ups. And believe me..I would LOVE to hear your demos.

But 99% of the music I consume..classic rock, jazz, blues, world, etc was recorded  and mixed in stereo will never be presented this way. You may disagree, but having seen many, many live performances, amplified and through sound systems, it's the way I believe we process music..stereo that is..of course with ambient sounds filling in the gaps. I am over simplifying for sure...

But...you are clearly on to something. For classical music, I really like the idea of hearing what the conductor hears. That is how the Fine's recorded those classic Living Stereo releases, from the perspective of the podium, not the 20th row, which became the fashion for a while. One well known conductor said the music swirls around him and he clearly had the best seat in the house, totally immersed in the majesty of the music.

Keep of the great work!

labjr's picture

Hi Barry

I wasn't thinking that some expertise isn't needed to prepare an album for production. I wonder though if the word "mastering" isn't overhyped at least since the CD age. Maybe the average person just thought "mastering" was part of the recording process. Or maybe "mastering" doesn't mean much with older mainstream music since it's almost never done properly.

Ninety percent of what I listen to are classic rock and pop titles which were recorded on analog tape. I don't care if it's "HD" or not. But I want to hear all the information that's on the analog tapes. And that's not what we get most of the time.

bdiament's picture

Hi labjr,

I don't believe mastering is overhyped, I think it is not properly understood.

To many folks, mastering means making things louder and basically boosting everything.  In view of what the major labels have been releasing the past several years, this perception is completely understandable.  Some mastering engineers compete via quantity instead of quality.

Another misconception I see widely in the audiophile world is that a "flat" transfer, i.e. an unaltered version of the original mix, is the ideal.  I was under this impression too - long ago, before I heard any masters. 

When you consider how most recordings are made (colored mics, used in large quantities, poorly placed, with the signal passed through hundreds of feet of mediocre cabling and finally "judged" using glorified car speakers, placed where there is a virtual guarantee of a skewed response at the engineer's ears), it isn't surprising that most masters need help.  This is where the "fresh ears" of the mastering engineer come in.

As an example, if I get a mixed master delivered with enough treble boost to peel the paint off the mastering room walls, and I can make it *hurt less* by the judicious application of EQ, then as I see it, EQ is a good thing (and a flat transfer would be a bad thing).  Here again, is where mastering enters the picture.

Of course, there are those cases (the minority) where the recording was very well made and things like EQ are not necessary.  Mastering is still required to get the best out of the recording.  As an example, recording levels which aim for the lowest possible distortion, will not hit an A-D converter "hotter" than about -6.  I leave lots of headroom when I record and since I'm at 24-bits, have no objections when the peak level on the original recording might be considerably lower than -6; I want it as clean as possible.  Final levels can be optimized in the digital domain and the results will benefit.  This occurs in (you guessed it, I'm sure) the mastering room.

I sympathize with our not getting all that the information that is on the source, whether analog or digital.  This is not the fault of mastering but of *poor* mastering and to a large degree, poor recording and mixing.  While I'm convinced the absolute quality ceiling of a recording has already been determined by the time the signals have left the microphones (*before* they are recorded), proper mastering ensures getting the best out of whatever the source contains.

Best regards,


funboy's picture

Very interesting article.  What others speakers are used in professional studios?  Seeing those B&W's made me think I should get speakers - active monitors or just regular bookshelves / floorstanders - that the recording engineers use to hear a sound closer to what they heard when mastering.

Dr. AIX's picture

The use of B&W speakers is actually fairliy unusual for professional rooms. The notable exception is Abbey Road which has been using them for a very long time.

You will see Westlake Audio speakers, Tannoy, PMC and Meyers in a lot of studios. It really depends on the type of music that a particular studio focuses on.

Bruce B's picture

It actually depends on what you mean by "studio" speakers.

Control room speakers are almost always self powered and like the above post says, are PCM, Meyer, Focal, Adam, KRK, Genelec and others.

On the mastering side, they are almost always passive and the engineer is sitting in the mid/far field, as opposed to the mix enginner sitting at a console

B&W are found in a lot of mastering rooms, as well as Wilson, Focal (Utopia), Tyler and older Dunlavy/Duntech.

Now I have to disagree with Mark here about analog tape. This tape can carry a bias freq of up to 150k, so why not be able to carry the overtones of a trumpet, or the harmonics that a Neve console can produce.

I did a little experiment on our Studer machines and have captured input signals of over  60k. So I feel tape, "can" be HD.


Dr. AIX's picture

Bruce, as the graphs within the article illustrate, you may be able to record and retrieve signals well above the normal range of human hearing but the attentuation of those frequencies hardly makes them usable as harmonic or partial reproduction. At just 40 kHz the signals are already down 6-10 dB. If you're getting anywhere near flat response to 40-50 kHz on a standard 24-track analog machine I would be very impressed.

The dynamics aspect of analog tape is the worst of the two basic parameters of recording on analog tape. Now it may be that dynamic range is not important to the sound of the particular project that you're working on but it is a defining characteristic of recording sound. If my definition of HD is meaningful to you and others than tape again doesn't qualify as HD.

If the only requirement for HD status is that we can record and playback a bias frequency on analog tape then we've had high definition recording since AMPEX added bias current to their machines back in the early 1960s. Obviously, the bias wasn't meant to be heard. That's why they put in out of the range of human hearing.

This is not a qualitative evaluation of analog tape based recording. It is an attempt to clarify what is and what isn't HD. As Dr. Sean Olive stated at the outset of this piece "vinly and analog tape are not" HD.

Bruce B's picture

"At just 40 kHz the signals are already down 6-10 dB."

Even hi-rez digital music has this attenuation as well on the many graphs I have posted. Even FFT of music on your own label have this phenomenon.

On the subject of dynamic range, even Keith O. Johnson states vinyl has a dynamic range of  >120dB !!


If your prerequisite of HD being dynamic range as a "defining characteristic", then 99% of recorded music does not meet this criteria. Surely you must be joking.

Looks like we'll just have to disagree on this subject.

Dr. AIX's picture

Bruce, I would love to say this is one of those preferred sonic aspects of our hobby but unfortunately it's not.

To your point that the highest partials in a real HD digital recording are lower than the fundamental and other lower harmonics, this is absolutely true. But an HD PCM recording maintains the correct amplitude of those signals in relation to the fundamental. Analog tape diminishes these same partials because of it inability to maintain flat response up to 48 kHz and beyond.

Keith Johnson is simply wrong when he (or anyone else states) that vinyl can deliver dynamics of greater than 120 dB! Virtually all vinyl is cut from from the master or a safety copy, which is historically an analog master. As one of the comments on your Youtube link clearly questions, the master tape is 60-65 dB (acknowledged by spec sheets and even hard core analog advocates). So how does the vinyl deliver more than the source that was used to create it. Very curious and certainly untrue.

That some engineers and producers choose to compress and modify the dynamics of their productions doesn't alter the acoustic reality of dynamic range in the real world. This is not joke. Do you really want to define HD music according to the practice of the music that is delivered through the radio, MP3 files and vinyl? The option is always there to limit the real world dynamics and you're right it is a very high percentage of music that is released. But just because something is artifically compressed doesn't make the whole world live by that standard.

The whole point of my advocacy of defining real HD music is to ensure that consumers will not equate the limited fidelity of the past and the overcompressed and limited frequency response of most commercial tracks with new recordings that really are high definition and maintain the original dynamics and offer the extended frequency response that digital alone is capable of reproducing.

Bruce B's picture

I agree with you on the incorrect information that was givien by Keith O. Johnson, but information like this can take on a whole new life, especially coming from an esteemed colleague. Stated specs are just what they are...

In the past, virtually all lacquers were cut from a tape copy, but these days, there are very FEW that are cut from tape. I'd even go as high as 80-90% that are cut from digital files. You "can" deliver more than the source by using upward/downward expanders.... but that is another topic.

In closing, until a standard definition is created and standard practices are implemented, anything can potentially be called HD beyond 16/44.1

For Dynamic Range..... who knows. There's great music out there with a "DR rating" of 11-13. Would this define HD? Who knows?. Until AES or NARAS gets behind this, the consumer will always be kept in the dark and posting on forums.

You're preaching to the choir!

Michael Lavorgna's picture

…from a consumer’s perspective is – is a “HD” download that originated as an analog master tape worth it? And I’d say, generally speaking, yes. In many cases the HD version will sound better than the CD and in some cases an analog master can provide greater than CD-quality.

Following this logic, the category ‘HD download’ can include albums sourced from analog. But even if we disagree on this point based on technical specifications, once again as a consumer of music the availability of 24/... downloads that sound better than the CD is to my way of thinking a great, i.e. better than good, thing. And companies like HDtracks are one of a few delivering historic content in this format.

I think this quote from Bob Ludwig from an interview on MusicTap handles this scenario well:

Now I love the new high resolution digital formats. Finally, the high resolution digital is always better than analog from a technical specification and, while not always, it can even sound better to our ears. I’m still a great believer in the use of tube gear and analog!

Regor Ladan's picture

Mr. Lavorgna:

I agree with your post. I didn't think it was worth getting in the middle of the good Doctor and Mr. Brown's spec debate because ultimately, music recorded on analog tape just sounds sweet. There is texture and a natural vibrancy. All the specs in the world concerning frequency response can't beat texture.

Having recorded local bands when I was younger over a ten year period, I can tell you the sound of rock IS analog personified. Some of those bands got signed to record deals based on my demoes.

But, let me finish by saying that I think digital is the best delivery medium for music. It portable, noiseless, and never deteriorates with play like unlike vinyl, which is highest maintenance home playback medium around.

I find it ironic that for years bands were recording on Pro Tools or some other digital work station and using plug ins to make it sound more analog!

Start with analog...deliver in digital.

That being said, I HAVE heard some very good native digital recordings that fooled me or left me unsure. So it goes back to "it's not the oven, but the ingredients."

Michael Lavorgna's picture

I have no issues with vinyl whatsoever. In other words, I very much enjoy listening to records and I feel sorry for people who don't.

And I also do not feel the need to make generalized pronouncements regarding formats. Beyond the fact that I am not involved in the recording process, I enjoy listening to music in all forms including 78s, LPs, CDs, downloads....

Music first, is my general rule.

labjr's picture

I'm not concerned if a digital format is "HD" or not. Only if it's transparent. For what I listen to and that's mostly old pop and rock music originally recorded on analog tape.

Virtually all the 24/192 transfers from analog tape I've heard seem to sound better so I'm not sure If I agree that 192 khz has no benefit. However, I haven't done a controlled comparison. But there are well known recordists who swear 192 is better.

I think it's fair to say there aren't many here who believe higher resolution digital formats will magically make analog tape transfers sound better than the original.

While audiphile recordings make good demo material, I don't think I'm going to start buying aboriginal acoustic music  because it was recorded with a special microphone pattern and some meitner converters.

labjr's picture

To me, the problem is using CD as a reference to define HD or high resolution. Analog was always better. For all these years we've been listening to a format that wasn't as good as what we had 35 years ago.

Regor Ladan's picture

There is no problem.

CD is high resolution. What we had 30 years ago was warped records with inner groove distortion, zero bass, and crappy pressings. To get a "playable" decent pressing of an LP today you have to fork over insane amounts of money to boutique labels like Analogue Productions.

$50 for the first Doors record? Getta outta here. Many do buy into the preachings of 60 year old hifi writers and their dogma concerning vinyl. They say THAT is high resolution. Even when cut from digital masters.

Michael Lavorgna's picture

CD is high resolution. What we had 30 years ago was warped records with inner groove distortion, zero bass, and crappy pressings. To get a "playable" decent pressing of an LP today you have to fork over insane amounts of money to boutique labels like Analogue Productions.

This is simply nonsense, sorry to be so harsh but it is - non-sense. If you feel that "inner groove distortion, zero bass, and crappy pressings" is something you cannot avoid, you have either very unfortunate luck or a very crappy turntable setup (or both).

Seeing as this site is focused on Computer Audio, I'm not going expend much more time/energy on this discussion but I cannot let this kind of misinformation go without calling foul. Foul!


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