47 Laboratory Model 4733 Pre Amplifier/USB & Coax DAC

Device Type: Headphone amp/Integrated Amp/Pre Amplifier/USB & Coax DAC
Input: 1 Digital Coax, 1 USB 44.1 kHz, 48 kHz (16 bits), 2 RCA line level
Output: 1 pair RCA, spring clip speaker terminals, 1/4" headphone
Amplifier: 2W/ch. @ 8 ohms
Dimensions (H x W x D): 123W x 96H x 208D mm
Weight: 1.7kg
Availability: through Authorized Dealers
Price: $2,000
US Distributor website: www.sakurasystems.com

Only The Simplest
I'll start by saying I've been a fan of 47 Labs designs from the first time I saw and heard the 4706 Gaincard and 4713 Flatfish. It helped that Herb Reichert wrote about the 47 Labs Gaincard (Listener, volume 5, number 2 Spring 1999) since he was a favorite writer on Hi-Fi and someone I felt I could relate to in ways that included non-Hi-Fi stuff (now that I've had an opportunity to meet Herb on a few occasions, I discovered I was righter than I knew). If a minimal design aesthetic appeals to you in a general sense, i.e. you enjoy the work of Ray and Charles Eames, Donald Judd, Ad Reinhardt, the Bauhaus, etc., then the design approach of Juni Kimura should tickle a similar fancy. Juni Kimura's quote, "Only the simplest can accommodate the most complex" adorns the 47 Labs US Distributor's home page.

The model 4733 Pre Amplifier / USB & Coaxial DAC is a new product in the 47 Labs relatively new "Midnight Blue" series that also includes the Model 4730 Tuner. The 4733 is also more accurately an integrated amplifier and headphone amplifier as it includes a 2W/ch. amp along with a preamplifer section and the USB / Coaxial DAC. Let's focus for a moment on the DAC. If you've read Juni Kimura's response in "The Future Of Computer Audio" article, you already know he's not a fan of upsampling. The 4733 uses the Burr Brown 2707 DAC chip which outputs at 16 bit / 48 kHz and the 4733 applies no upsampling or digital filtering.

For some, especially for those interested in playing high definition music files in their native format, this choice will be a deal breaker. For others, granted their numbers may be small, this may not raise an eyebrow. Because of 47 Labs very distinct approach to hi-fi design, it's clear their products are not meant for everybody (I envision 47 Labs owners as a club or tribe giving each other a subtle motorcyclists thumbs up as they pass in the night).

The amplifier section is related to the 47 Labs Gaincard, i.e. it employs a very simple circuit and opamp to produce the 4733's 2 Watts of output power (did I hear someone snicker? Read on). To use your 4733 is as straightforward as connecting it to your PC (USB cable), to your Hi-Fi (varies depending on whether you use the 4733 as a preamp-only or integrated amp but we all know about interconnects and speaker cables) and making the appropriate changes to your software settings (essentially pointing your system's sound output to > USB DAC). The 4733 also offers a coax input so you can connect your old school transport (like a 47 Labs Flatfish) as well as two line level inputs for a tuner, or turntable + phono stage, or tape deck or CD player.

The Sound of Simplicity
I used the 4733 mainly with two pair of headphones: Stax SR-5Ns by connecting the Stax SRD-6SB's "Adaptor for Earspeaker" in-built speaker cable to the 4733s spring clip speaker terminals (another choice that may have some running for the hills) and the Audio Technica W-1000s straight into the 4733's 1/4" front-mounted headphone jack. My iMac served as front end with Audirvana's free player acting as my player of choice. USB cables included the stock cable from 47 Labs and AudioQuest Forest and Carbon.

To put it in a nutshell, the 47 Labs Model 4733 sounds clean. It sounds pure. Music flows through naturally and it plays unencumbered by any hint of grain, strain or grunge. Something like my ripped copy (using EAC) of Dead Can Dance's Into The Labyrinth sounds positively cavernous and convincingly creepy lending Lisa Gerrard's voice a perfectly lit stage for display. Pump's The Decoration Of The Duma Continues is a new release of music recorded in 1986/87 but you'd never guess if judged by the excellent sonics or the challenging world-infused sound and you can grab onto every slippery sonic slope Pump delivers. Perhaps a perfect spiritual mate to the 4733's minimal approach and way with music is Sonny Rollin's Freedom Suite which I've been listening to for decades and have yet to grow tired of. Here the 4733 shone in all its colors which is to say it allowed Sonny Rollin's and Co.'s simple yet as complex as you can handle music to communicate completely.

If you have a large collection of CD-quality files and you enjoy the fact that you feel they're well-recorded, the 4733 provides access to a full sonic palette and its sense of pace, meaning no emphasis on leading edges or bass bloat, is excellent. If on the other hand you have a large collection of high resolution music, I'd have to say look elsewhere. Simpler is better applies to higher resolution files as well and in general I'd say go native.

And If You Have A Really Big Desk
Why not? I mean, you would too if given the chance. I own a few amps that are 8 Watts per channel and under and if there's one piece of information relating to Hi-Fi and misunderstanding that takes the cake it's the idea of power. With Watts, some seem to forget that an amplifier is only part of a system and Watts don't mean squat until we add the other half of the equation—the loudspeaker. The 47 Labs 4733 drove my 1967 pair of somewhat ratty-looking but heavenly sounding Altec Valencias to clean, clear highs and lows with nary a hint of strain and the combination was as dynamic as the music you fed it. You could, especially if you were shopping for an amplifier, give all the credit to the 4733. But getting back to the fact that we're talking about a system, the Valencias are an easy dancing partner (16 ohm/100dB per watt per meter).

While at the recent Rocky Mountain Audio Fest, I spoke to Gideon Schwartz of Audio Arts. Audio Arts is a 47 Labs dealer and when I shared my 4733/Altec Valencia experience with Gideon, he shared that he's got at least one client that has paired up the 4733 with the Voxativ Schmimel Ampeggio horns. If you are one of what I imagine are a limited number of people looking for a simple un-boxy one-box solution to drive your high efficiency loudspeakers and/or headphones with 16/44 music from your computer, a CD transport and one or two other line-level sources, you may have found your perfect match. Juni Kimura casts a narrow yet highly focused and to my ears a quite wonderful sounding net.

What Price, Value?
Let's take care of the elephant in the room before we go—the 47 Labs model 4733 Pre Amplifier / USB & Coax DAC is not a screamin' bargain. If you want value in terms of parts-cost per dollar (not to mention Watts/dollar), shop elsewhere. And clearly many people have no reservations buying cheaper imitation clones of original ideas—there are more Gain-clones floating around than originals. Just as there are crappy Eames lounge chair clones literally littering the streets at least where I live as I picked up this attractive example (pictured above) in someone's driveway earlier today just to illustrate this point (funny timing, no?). [btw - I'd be willing to trade this for an original and I'll even throw in an original Picasso copy to sweeten the deal]

I get the distinct impression that Junji Kimora is going to do what he chooses regardless. While some may take offense to a no-compromise attitude especially in these "Where's mine" times, I enjoy and take delight in an uncompromising vision especially when it translates into listening pleasure.

deckeda's picture

I gathered from the Japanese translation Kimora thinks playing something back at its native sampling rate is akin to upsampling it. He seemed to want to make that inference.

It'll be interesting to see if the file format/sampling rate "standards" he's waiting for, before moving on to high resolution compatibility, will materialize (in whatever way he envisions) before the Burr Brown 2707 is mothballed.

Yay for tackling an interesting piece of gear from a unique company. Despite my whining I don't wish for a cookie-cutter homogenous product from anyone, and I have no reason to doubt how good the 4733 sounds. Bonus points for rocking the Altecs.

Michael Lavorgna's picture

Thanks deckeda and it sure did rock them Altecs. That would make for a very cool, minimal/maximal system.

pspcpog's picture

Your NOS dac list led me to this page and I've found the 4733 pre quite an elegant solution. I was just wondering if 4733 has an active linestage or a passive one as the original gaincard.