The Questyle Audio CMA800R 'Golden Series' takes all the great technology found in the standard version but adds Roberts ceramic PCBs, for ultra-low signal loss and extremely stable transmission, and select components on the current mode amplification circuit. These additions combine to offer an exhilarating performance in sound quality and technical specification. The transparency of signal processing is improved significantly.

Hear music for the first time

Questyle Audio’s outstanding "Current Mode Amplification"  technology provides the airiness and musicality of a tube amp while maintaining the speed and accuracy of transistors.

What is Current Mode Amplification?

In current mode amplification, the signal is amplified by modulating current instead of voltage. This is widely applied in the high-speed communication industry and the video processing industry, but it is Questyle Audio’s patented technology that is applied to headphone amplifiers.

Why Questyle choose Current Mode Amplification?

Low distortion and wide bandwidth are the goals of all high performance amplifiers. Only with ultra wide bandwidth and high speed processing can an amplifier process sudden pulse wave signals and achieve wonderfully realistic playback of the music signal with speed and transparency.
To achieve this Questyle Audio abandoned the traditional voltage mode format and developed “Current Mode” amplification.

When the component is working in “Current Mode”, the amplifier Slew Rate (SR) achieves a linear increase as input signal amplitude increases, in direct proportion to the input signal amplitude. When receiving a high amplitude signal, a “Current Mode” amplifier’s SR is much faster than traditional voltage mode devices, totally eliminating TIMD and ensuring a high amplitude signal, with an extremely wide linear bandwidth and an almost distortion free realistic playback.

Work principle

To maximise accuracy, current capability, and consistency, Questyle Audio’s “Current Mode” amplifier employs all discrete componentry, in a Class A configuration. To insure maximum compatibility with source units and speakers (headphones), input and output both work in voltage mode.

From the diagram we can see, input signal will travel first to VCCS, voltage mode is converted to current mode here, then it goes to Ai for amplification (in current mode), next it goes to I/V converter to become voltage mode again, and then is output to OPT stage to drive headphones.

Physical

Weight:
5 kg
Dimensions:
340mm(W)x145mm(H)x515mm(L)

Electronics

Circuit Board:
Rogers Ceramic printed circuit board

Performance

Work Status:
Pure class A
Frequency Response:
DC-200kHz (=0, -0.3 dB); DC-650kHz(+0, -3 dB)
THD+N-Mono Mode:
[0.00026%] @1kHz, 300ohm
THD+N-Stereo Mode:
[0.00038%] @1kHz, 300ohm
SNR-Mono Mode:
118dB
SNR-Stereo Mode:
114dB
Max Output Power-Mono Mode:
710mW (15Vrms) @300ohm
Max Output Power-Stereo Mode:
180mW (7.5Vrms) @300ohm
Gain:
15.5dB

Connections

Output-Pre-amp:
RCA pair
Output-Mono:
XLR Full Balance
Output-Stereo:
Dual 6.5mm headphone jacks
Input-Mono:
XLR Full Balance
Input-Stereo:
XLR, RCA

Authorised Retail Partners

Audiologica
Audiophilia
Highend Headphones
Igloo Audio