The Wavelength Audio Crimson HS with Quotient Q1 DAC Module / Silver Transformers
Input: USB 2.0 Streamlength Asynchronous USB code
Output: (1) Pair Unbalanced (RCA)
Dimensions: 10" wide by 12.75" deep, by 3.5" high chassis, with tubes 8" high / Power supply is 4" wide by 4.5" deep, by 2.5" high
Weight: 23 pounds
Quotient Q1 DAC Module upgrade: $1500; Supports 32/384 kHz and DSD 64 / DSD128
Availability: Authorized Dealers
Price: $7500 with standard Numerator Module; Silver Transformers add approximately $9500. The actual price will be determined by request. Volume Control is $750
Price As Tested: $19500
The Wavelength Audio Quotient DAC Module is a new upgrade for the Crimson High Speed USB DAC that has added DSD 64 / DSD 128 as well as support for PCM files up to 32/384 kHz. But the Quotient Q1 adds far more to the Crimson than just DSD and increased PCM sampling rate support. Gordon Rankin has gone back to the drawing board for this new DAC module resulting in a number of improvements for his flagship DAC.
I reviewed the Crimson HS DAC with the Denominator Module back in July of 2012 (see review). At that time, I was quite impressed with the Crimson’s performance, having found it to be very transparent from top to bottom and with a richness of sound that seemed quite real for acoustic instruments and voices. But since that review, I have had the opportunity to evaluate a number of expensive, excellent sounding DACs that more than challenged the Crimson HS’s sonic performance and ultimate DAC rating. Also, DSD playback has become a standard feature for most high end DACs being sold today; something that the Crimson / Denominator lacked. For me, the big question was how the Crimson HS USB DAC compares to some of the best DACs I have heard utilizing the new Quotient Q1 DAC Module.
Crimson HS USB DAC Basic Design
But before I discuss the new Quotient Q1 Module and its improvements, I would like to review the basic design features of the Wavelength Audio HS USB DAC.
The Crimson uses an output section that is totally tube driven. The high voltage stage is rectified by the EZ80/6V4 rectifier which is smoothed by a filter choke and a large number of Black Gate capacitors. The 71A output tubes are supported by massive custom built MagneQuest audio chokes and output transformers that add significant cost to this tube DAC. The 71A directly heated triode tubes date back to the 1920s and were the output tubes used in many early radios including the RCA Radiola 17 of 1927. The 71A was also employed by the United States military for amplifier applications. Even though it has been many years since the 71A has been manufactured, it is relatively inexpensive and plentiful with large stocks of unused inventory including Joint Army Navy (JAN) select 71A tubes.
Another unique feature of the Crimson is that the DAC board is driven by an SLA (Sealed Lead Acid) rechargeable battery. The battery provides approximately 18 hours of operating time. The Crimson manages the recharging of the battery when the DAC is in stand-by mode. Engaging operating mode by turning on the computer turns off the recharging feature. 3 LED indicators indicate standby/ recharging/ and operation modes of the Crimson. There are no external switches on the Crimson; all appropriate functions are automatically engaged when connected to an “on” computer.
The High Speed Crimson isolates the computer from the USB DAC with high speed optical isolators.
The Crimson is a modular design allowing one to upgrade the DAC easily with plug in DAC modules. The standard Crimson comes with the Numerator Module, a 24/192 module based on a Wolfson DAC chip. The Quotient Q1 upgrade is $1500 and user replaceable for those that wish to upgrade at a later date.
The Crimson is supplied with an external power supply with a 5 foot connecting cable and an IEC connector for those that desire to use upgrade AC cables. Wavelength Audio suggests that the external power supply not be placed alongside the DAC to reduce induced DAC noise.
The silver wound transformers are another upgrade for the Crimson that enhances the DAC’s ability to reproduce fine detail and subtle nuances in recordings. With the silver wound transformers you can hear spatial details that are lost with the copper wound transformers. One can hear greater transient detail and micro dynamic reproduction with an enhanced sense of openness to the sound with the silver transformers.
The case work for the Crimson is impressive looking with its solid aluminum top and bottom plates along with natural wood front panel facing. The 3 tubes are plugged into the top of the DAC making access easy and direct. With the attractive wood front panel and the tubes, one gets the impression that this is a piece of electronics from the early 20th century, but the design of this DAC is anything but early 20th century. The 3 feet of this DAC are Black Diamond Cones that improve the DACs isolation from external vibration.
The Quotient Q1 Module
The Quotient Q1 Module has increased sample rate support from the 192 kHz of the Numerator and Denominator Modules to 384 kHz. DSD playback is supported with the Quotient that includes DSD 64 and DSD 128. This module features the new ES9018 DAC chip along with a new IV discrete stage with inter-stage transformers. Discrete power supplies are used for all the analog supplies and the master clocks. An FPGA (Field Programmable Gate Array) based DoP allows the Crimson to decode both PCM and DSD. The FPGA automatically sets the ESS Sabre DAC chip into either DSD mode or PCM mode. New low noise oscillators were also employed in the Quotient. A minimum phase filter is also employed on the Quotient Q1.
I asked Gordon Rankin, chief designer and owner of Wavelength Audio, to describe the changes in the new Quotient Q1 Module:
Four sections have changed since the design of the Denominator module:
I added the FPGA section for the DoP specification. I evaluated the software DoP solution that XMOS did and it just didn't work for me. So we asked Pavel Valousek of Audiopraise to help me out. Pavel had done work with a few other companies that were really pleased with his work. A small Microchip microcontroller sets the ES9018 up with Minimum Phase Filters for PCM data and also sets up the ES9018 when DSD data is being sent. That microcontroller goes into sleep mode when any music is streaming to the DAC chip. The output of the ES9018 is converted to voltage by quad discrete transistors on each channel and that is feed to the analog section of the DAC. In the Cosecant that goes directly to the tube stage and in the Crimson the differential pair is sent to a 1:1 transformer for single ended output.
We are using new oscillators that have much better phase noise than the Crystek we used before.Associated Components Used in This Evaluation
In the analog stage, I came up with a new discrete IV section using THAT Corporation discrete matched transistor found in the Cosecant Denominator. I rolled those changes into the Quotient Q1.
A new USB module board for the Crimson HS has been designed that is installed at the same time the Quotient Q1 is installed. Installation of the 2 boards is very easy and obviously an in-field modification thanks to the Crimson’s modular design.
An early 2011 MacBook Pro 2.3 GHz, 16 GB RAM with Samsung SSD was used with 2 GRAID Thunderbolt drives for the music libraries; one for PCM and the other for DSD files. OSX Yosemite and Boot Camp Windows 8.1 64 Pro were the operating systems. I used Audirvana 2.09 and Pure Music 2.02 with OSX Yosemite. Foobar2000 with Fidelia Pro 6.5 were used for Windows evaluations
The GRAID Thunderbolt drives were powered by HDPlex linear power supplies. An iFi Micro iUSBPower was also driven with an HDPlex linear power supply. One component that has made a big difference in the performance of my system was the Shunyata Research Hydra DPC-6 Power Center. Filtering the digital noise placed back on the AC line and effectively firewalling it allowed me to get a truer impression of the DAC’s sound. The MacBook Pro and the hard drives are plugged into the DPC-6. The iFi Micro iUSBPower and the Crimson were plugged into a Shunyata Research Triton Power Center.
Another set of components component that greatly helped me in the evaluation of the Crimson / Quotient was the addition of the new Synergistic Research Atmosphere Level 4 interconnects and speaker cables. The Atmosphere Level 4 cables replaced my Synergistic Research Tesla series cables. For now, I’ll just say that the new Atmosphere Level 4 cables allowed me to hear things that were obscured by my 6 year-old Tesla series cables; especially in the reproduction of complex musical passages.
The computer and the DAC were each placed on Synergistic Research Tranquility Bases powered by their Transporter Ultra SE. Synergistic Research Thunderbolt Active SE cables are used for the hard drives. The USB cables used in this review were the Synergistic Research Galileo LE, the JCAT Reference USB cable, and the Audioquest Diamond USB cable.
The Crimson’s Sound Evolution
I have been well acquainted with the numerous changes and improvements brought to the Crimson by Wavelength Audio since it was first released in December 2006. From the original DAC with the Transcendental Module 16/44.1, to the first implementation of the Asynchronous USB interface for high end DACs in 2007, followed by the Numerator and Denominator modules with the introduction of High Speed USB support, there has been a steady improvement to the sound of the DAC while preserving its basic sonic character.
The Quotient Q1 Module, while continuing this tradition of sonic improvement, has gone farther than any of the previous DAC Module upgrades in improving the over-all sound of the Crimson while introducing new features such as 384 kHz and DSD support.
When I first listened to the Quotient Q1 and compared it to the sound of the Denominator, I was struck by how different the two modules sounded. The Quotient has a bigger soundstage that significantly stretches beyond the outer borders of my speakers with excellent front-to back depth. As good as the Denominator was in soundstage recreation, the Quotient is in another league of performance. In fact, the Quotient produces one of the largest, if not the largest, soundstages I have yet experienced. But the soundstage improvement goes far beyond just size. The soundstage is richly layered with natural air and bloom around the instruments.
But the sonic improvement that I feel is the most important and significant, is the reduction of hardness or grain in the overall sound. The Quotient has, quite frankly, a gorgeous midrange sound that is the most Single End Triode sounding of any Wavelength DAC I have heard. In fact, I have yet to experience any DAC that can reproduce the midrange beauty that is found in the Crimson / Quotient. This is not a tube coloration type sound, but a level of sonic purity and tonal naturalness that is heard with live acoustic music. The Quotient is harmonically rich with a relaxed presentation that is very addicting once experienced.
The Quotient Q1 is very revealing and displays excellent micro and macro dynamic changes with a well-defined low end. Micro dynamic nuances are readily apparent listening to this DAC. There is no midrange fullness of the mid bass resulting in a loss of definition and transient detail. The high end reproduction of the DAC is capable of excellent resolution that is delicate in tone and texture.
The only minor shortcoming I did observe is that the ultimate weight and slam of the bass falls slightly short of the best DACs I have heard. I do believe that most critical listeners will never miss a thing concerning the Crimson’s bass performance.
PCM vs DSD Performance
The special sound qualities I previously identified were found in both PCM and DSD playback. The Quotient was consistent and completely stable playing PCM and DSD files. The special qualities of both PCM and DSD were easily recognized listening to the Crimson. Unlike some DACs I have heard, the Crimson is equally at home with either format.
Exploring My Music Library with the Crimson / Quotient Q1
Cassandra Wilson’s New Moon Daughter 24/192 provided an excellent example of the Crimson / Quotient Q1’s ability to reproduce deep bass with impact and definition without obscuring the midrange. Cassandra’s voice was clear and focused with subtle guitar strings emerging from a black background. I don’t remember hearing this recording reproduced as well as I experienced it with the Quotient Q1.
Vladimir Ashkenazy / London Symphony Orchestra conducted by Andre Previn performing Rachmaninoff’s Piano Concertos, 24/96 displayed the fabulous sound staging capabilities of the Crimson / Quotient. The acoustics of the recording venue were reproduced not only with an enveloping soundstage of great width and depth, but with a sense of air around the instruments. The piano was well focused and was not masked by the orchestra’s crescendos. The orchestral dynamics were well reproduced from this wonderful recording.
The Crimson / Quotient can deliver the exciting rhythm and percussion as demonstrated by The Dunwells’ Blind Sighted Faith 24/96. The DAC drew me into the performance with toe tapping rhythm and percussion with solid bass impact. The Crimson / Quotient reproduced multiple voices with sharp focus and no congealing of the sound.
The macro and micro dynamic qualities of the solo piano were easily captured by the Crimson / Quotient reproducing Junko Inada’s piano performing Sergei Rachmaninoff 24/192. The piano was portrayed with wonderful dynamics that emerged with a natural bloom in this attractive recording. The dynamic percussion of the piano strings and the piano’s overtones were reproduced without a trace of hardness or loss of focus.
The Crimson / Quotient Q1’s DSD performance is exemplary. The same analog-like qualities I heard with PCM file reproduction were heard with DSD files. The soundstage was just as magnificent as that heard with PCM file playback.
Listening to the Misa Criolla performed by Musica Temprana (DSD 64 from native DSD) was a new experience for me with the Crimson / Denominator. Most DACs I have listened to with this recording have a slight hardness to the sound, but not the Crimson. The stereo version I listened to was vibrant and a highly rhythmic musical composition. The Crimson reproduced the acoustics of the recording venue in an engaging soundstage that drew me into the music. The resolution of low level detail was exemplary with macro and micro dynamics beautifully reproduced. But what I enjoyed the most was the way the Crimson / Quotient was able to reproduce multiple voices. The DAC seemed to breeze along when the musical passages became more complex and never lost its ability to retain focus while maintaining a relaxed presentation.
I listened to a number of DSD 128 titles, but when I saw the old war horse, Cantate Domino at Native DSD, I just had to go for it. The original Propius recording was recorded by Bertil Alving in 1976. The record was a popular audiophile showpiece back in those days. From Native DSD:
“For the 2xHD transfer of this recording, the original 1/2”, 30ips NAB master tape was played on a modified TELEFUNKEN M15 Tape recorder with SAKI head, using a hi-end tube preamplifier with OCC silver cables. We did an analog transfer for each HiRes sampling and A & B comparisons were made with both the original LP, using the Kronos turntable, as well as with the best available CD, using the Nagra HD Dac and dCSVivaldi DAC, throughout the process.”The DSD 128 version was made using the Ayre QA9 DSD Pro A/D converter.
The DSD 128 version of Cantate Domino was simply stunning when played back through the Crimson / Quotient. The immense acoustics of the hall were beautifully reproduced. The organ had power and weight of the real thing that’s to the use of my Wilson subwoofer. The choir was beautifully captured in this recording with excellent resolution of the different voices. When the choir, brass, and organ played together, the sonic result was spectacular given the bloom and dimensionality of the recording.
Gordon Rankin’s Finest Work
There is no doubt in my mind that the Crimson / Quotient Q1 represents Gordon Rankin’s finest work to date. The improvement over the previous Denominator module will make the Quotient Q1 a must-have upgrade for the High Speed Crimson owner. The harmonic correctness and spectacular soundstage properties of this DAC are the finest I have yet heard from a digital product. The resolution and transparency of this DAC, especially with the Silver output transformers, will provide a unique musical experience for computer audiophiles lucky enough to own this product.