The last couple of years has seen Questyle Audio bring to market some excellent high performance audio gear. Their Current Mode Amplification pure Class A (which can be read about in detail on their website) brought power and finesse to the QP1r portable DAP and their CMA800R Headphone amplifier. They have also impressed with the CAS192D DAC. It was inevitable that they would take what they had learned from these products and come out with a DAC/Headphone Amp combo. Which brings us to the product this article is focused on, the CMA600i.
Weighing in at a solid seven pounds and measuring a desktop saving 13X11.8X1.4 inches the CMA600i packs a wallop. 220mW @300 Ohms Single Ended and a max of 1900mW @32 Ohms in Balanced mode means full Class A power at appropriate and plentiful amounts for most any headphone. This is a fully balanced design too offering four groups of pure Class A current mode circuits to provide the power when using the four pin XLR output. The unit is filled with high quality audiophile grade parts such as DALE resistors, Nichicon FG Capacitors and ALPS potentiometers. As I will describe later the high quality sound is no accident. Every component is top grade.
All of the inputs are digital with one RCA Analog input available for an external amp which would make the CMA600i an DAC only unit. Just flip the front external amp toggle switch. Digital is THE game as the latest flagship AKM4490 chips are the heart of the D/A system. Questyle Audio powers each chip independently to maximize dynamic range. Any fan of DSD will be pleased to know you get the full SACD standard treatment with an independent DSD channel. Nice!
One added welcome benefit is the opportunity to use the CMA600i as a full-fledged DAC/Pre-Amp for two-channel use. The CMA600i can act as the digital heart of a two-channel system. A pair of balanced and single ended outputs allow you to add an external power amp to your rig and go headphones or speakers as desired. Another solid value play by Questyle Audio.
Headphones are what we came here for though and Questyle’s design and listening tests utilized several reference class headphones to insure compatibility and high end performance. Dynamic, Planar Magnetic and even IEM’s were used to conduct extensive factory listening tests before they were satisfied with the final performance of the CMA600i. They also burn in every unit for 72 hours prior to shipping, which helps explain why it was a solid sound right out of the box with only a small improvement coming from additional use. The unit does not have a fan so it is completely quiet and it does not get more than warm to the touch. You will not need a lot of clearance for proper ventilation.
Time for some listening. First up is James Blake’s Limit to Your Love, from his self-titled album. (Tidal, ATLAS, A&M, Polydor 2011) James blends Electronica and Dubstep with R&B. The uses of deep sub bass synths really test the low end frequencies. So this was a task for the Audeze LCD-X’s. The pulsing bass was tight and exact. Not flabby and distorted. Throughout the song different percussion come through giving excellent spatial cues across a wide soundstage. The space was highly discernable too. You could sense the mic positioning and the room surrounding the singer. The piano tone was appropriate and you could hear the use of the pedals. James’ vocals were clear with no midrange digital edge coming from the streaming source material. The Audeze’s were a perfect instrument for enjoying this song and the CMA600i served up the presentation beautifully.
Next up was Flyleaf’s Memento Mori album (iTunes Download 16/44 256bps AIFF, A&M/Octone 2009) and Beautiful Bride. The MrSpeakers Ether C’s are well suited for metal. They easily manage the speed and intensity of the genre allowing the power and intricacy of the music to flow. Lacey Sturm is often considered in the same vocal conversation with Amy Lee from Evanescence and her powerful vocals came through clearly within the delivery of the twin guitar attack. The Ether-C’s closed Planar Magnetic construction offered a tight articulate delivery as the CMA600i DAC enabled each instrument to be perceived individually. No smearing was present as the sonic wall moved the song forward. Recreating the scale of an operatic metal song requires power and nuance as well as the ability to maintain the cohesion of the presentation even when filled with tight musical articulation of the instruments. The CMA600i allowed the Ether-C’s to be at their best.
Moving on to Van Morrison’s Moondance (HD Tracks 24/192 AIFF Warner Bros. 1970) I selected Into the Mystic. One headphone that I found was not only a great companion to the CMA600i but also priced more in line with its $1299 USD price tag were the $599 AudioQuest NightHawk’s. The NightHawks offer as speaker like a presentation as I have found. They also have a very unique sonic signature. They have a clarity and tumbrel rightness that makes them a great long listening session choice. They also come with a pair of cable options based on the highly regarded AudioQuest Castle Rock speaker cables. As a semi-open design they allow the spaciousness offered by the CMA600i and yet they can do full justice to an intimate presentation such as this Van Morrison classic. The strumming of the guitar offered the texture of an in person performance. High hat cymbals shimmered crisply and with just the right tonal sheen. Van’s weary vocals had that weight of the world feel conveying the relief at his journey turning homeward bound. The NightHawks paired with the Questyle conveyed the emotion of the track as needed. The NightHawk’s are a wonderful pairing with the Questyle rig.
As a long time Alan Parsons fan I had to queue up Sirius from Eye in the Sky (CD Rip 16-44 1411bps AIFF, Arista 1982) The spatial density and mastering expertise of Alan Parson’s albums always has me reaching for my Sennheiser HD800’s. Open, layered and vast is what I appreciate about this first track. The CMA600i had no trouble driving the HD800’s (I had no doubt at this point) what really was nice was more about the DAC and its ability to take this digital CD rip and take the edge off without subtracting the detail. Snare drum’s snapped, cymbals shimmered and the sense of width and depth recreated the appropriate mood. Having enjoyed this album for over thirty years I fully appreciated the quality of the presentation.
Putting the CMA600i to the test against unfair competition I played all the songs and headphones on the Simaudio Moon 430HAD. The 430HAD is also a DAC/Amp that can be a pre-amp as well. It utilizes the ESS9018 flagship DAC chip and has overly large power supplies for its DAC and amp sections. It also runs $4300 vs the CMA600i’s $1299. The Moon 430HAD won the day, but I would call it an unfair fight. At 3 ½ times the price it should do a better job. Soundstages were better defined. Detail was clearer. Low end had a firmer grip. But…Not by a huge margin. This was a classic example for reaching for that last few percent of what can be done. The Moon is a true flagship in performance as well as price. For the wallet conscious consumer (read that most of us!) a Questyle/AudioQuest matchup gives you a true taste of champagne with cash left over for other things.
Questyle Audio has done it again. This is a near reference unit for a quarter of the price usually associated with reference level performance. The attractive industrial design coupled with their patented current mode pure class A output provides the listener with stellar sonic reproduction. The AKM4490 powered DAC has virtually no digital edge to the presentation.
High end build quality using audiophile reference quality parts CNC’d and assembled in the Foxconn China plant where the Apple iPhone is built.
Solid performance for a variety of headphone technologies
Compact attractive convection cooled design allows flexible unit placement
Outstanding sound quality
No IEM 1/8” specific output
Front panel lettering is hard to read from a distance.
Product Type: Headphone Amplifier with DAC and Pre-Amp
Chassis: Silver/Space Grey
Chassis Materials: Special CNC tooled aluminum
Dimensions: 12.99” (330mm) W x 11.81” (300mm) D x 1.38” (55mm) H
Weight: 113oz (3.2kg)
Working Status: Patented Current Mode Pure Class A
Voltage: 100-120V or 220-230V, switchable
Power consumption: 18W
Headphone Amplification Section
Gain: 13.4dB (4.7 times)
Max Output: 220mW@300 Ohms, 950mW@32 Ohms (Single Ended)
630mW@300 Ohms, 1900mW@32 Ohms (Balanced)
THD+N: 0.00057%@1kHz, Po=100mW, 300 Ohms
0.00034%@1kHz, Po=50mW, 32 Ohms
Frequency Response: DC-100kHz (+0, -0.7dB) ; DC-600kHz (0, -3dB)
Input: Internal Dac Output external RCA, switchable
Output: Dual ¼” (6.35mm), 1 x 4 pin Balanced output
DAC and Pre-amp section
Supporting Files: SPDIF and Optical: PCM 44.1k-192k/16-24 bit
USB: PCM44.1k – 384k/16-32 bit, True DSD64-256, DoP 64-128
Supporting OS: WIN XP, Vista, Win 7, Win 8, Win 10, MAC OS
Digital Input: SPDIF, Optical, USB Type B
Kernel Streaming: WASAPI, ASIO, KS
Digital Filter: PCM mode, IIR (MP) and FIR (LP) Switchable; DSD mode; no filter
Output: XLR and RCA
Max Amplitude: XLR: 8.6Vrms; RCA: 4.3Vrms
Analog output: THD+N: RCA<0.00082%, XLR<0.00064% SNR: RCA > 105dB, XLR > 121dB
Price: $1,299 USD
Sennheiser HD800’s with Toxic Cables Silver Widow SW22 cables
Audeze LCD-X’s with Toxic Cables Silver Widow SW22 Cables
MrSpeakers Ether C’s
Simaudio Moon 430HAD Headphone Amp/Dac
AudioQuest Diamond USB
Apple MacMini with Roon