Questyle Audio CMA600i

The Questyle CMA600i is a high-quality, high-end headphone amplifier and DAC combination unit. The CMA600i inherits Questyle Audio flagship headphone amplifier patent “Current Mode Amplification” technology, adopts all discrete circuit design, working in pure class A status. Thus it can provide best sound required with ultra-low distortion (0.00042%) and DC-600kHz (+0,-3dB) ultra-wide frequency. With it’s high quality sound performance, the CMA600i is capable of challenging world class Hi-end headphone amplifiers.

The Questyle CMA600i is equipped with 4-pin full balanced output and dual 6.35mm standard headphone jacks. When the 4-pin full balanced output is working to drive a headphone, there are 4 groups of pure Class A and Current Mode amplification circuits output double voltage, and bringing quadruple power, so it can easily drive any high impedance headphones.

From a DAC perspective, the CMA600i selects the AKM AK4490 as its DAC chips of choice. Different from other DAC chips, CMA600i is specially designed with a +/-7V ultra high voltage power regulator to independently provide power for AK4490, which befits the CMA600i with ultra large dynamic range.

CMA600i USB input supports PCM 44.1k-384k /16-32bit signal, and True DSD64, DSD128, DSD256, DoP (DSD over PCM)64 ,DoP128 converting. It also supports 192kHz/24bit optical and SPDIF inputs.

CMA600i inherits Questyle patented “True DSD converting” technology. CMA600i drives program directly and processes DSD source code of PC, and CMA600i hardware provides special DSD channel to process the signal strictly under SACD standard.

As Mac OS doesn’t support True DSD converting, CMA600i is also designed to convert DoP signal.

The CMA600i is designed with an independent Pre-amp, following “Current Mode Amplification” patent technology. The Pre-amp uses an independent circuit, output with RCA and XLR cable, max amplitude with 4Vrms and 8Vrms separately. Volume control is handled in the analog domain with an ALPS motor potentiometer. CMA600i is equipped with a remote control, convenient in driving active speakers.

Sound quality depends much on components. Plitron customized triode transformer, over 10 groups of independent power regulation, specially selected WIMA capacitors, DALE resistors, Nichcon FG capacitor, Neutrik Connectors…all these Hi-end components ensure the CMA600i provides unrivalled sound at its modest price point.

Each CMA600i is made in the acclaimed Foxconn factory under world-class manufacturing standards. The chassis is made of aviation aluminum, assembled in CNC “multual bit” structure, 10mm in thickness to reduce resonance. Spikers are pure aluminum as well, specially tooled by Foxconn CNC machines.

The CMA600i design was completed within 3 months, but its sound alignment took over one year to finesse.

Questyle changed over the main circuit design five times, selected over 50 different components, 10 different headphones, 5 pairs world famous active speakers, and more than 500 times sound alignment, to achieve the wonderful sound from the CMA600i.

Every CMA600i, after assembly is completed, is  burnt-in strictly over 72 hours under high temperature and high voltage, and one more time before shipment. After that each CMA600i will go through a specification test by AP2722, then get a test report.

Every testing report has two copies. One is for the customer, and the other is kept at Questyle for product tracking and maintenance.

REVIEW – THE AUDIOPHILE MAN