A FOLLOW-UP TO THE WIDELY POPULAR A90, TOPPING INTRODUCES A FULLY BALANCED HEADPHONE AMPLIFIER A90 DISCRETE

Topping is known to make the quietest and most linear power amplifiers. The design engineers at Topping develop the amplifiers with precision delivering out-of-the-box audio performance. The concept and products of Topping have won the recognition of audiophiles worldwide. Since Topping first unveiled the A90 in 2020, audiophiles went berserk. The A90 Discrete is no different from the great products that Topping consistently offers with comprehensive, high-performance features. The Topping A90 Discrete is a fully balanced headphone amplifier that can also act as a pre-amplifier. The design overhaul on the A90 Discrete compliments the output power handling capacity. You will be able to drive high impedance and low sensitivity headphones/IEMs with ease. The differences over the classic A90 are that the A90D incorporates the Discrete Nested Feedback Composite Amplifier with a THD+N of <0.000055% as compared to <0.00006% on the classic A90. The Topping A90 Discrete also has higher output power ratings and an R2R relay volume control that reduces channel imbalance delivering optimum performance.

AN NFCA MODULE FUSED WITH UHGF AND OPTIMISED VOLTAGE CURRENT HYBRID FEEDBACK ARCHITECTURE DELIVERS CLEAN AND PRECISE AUDIO PERFORMANCE

Packing an ultimate performance with fully-discrete NFCA modules, the all-new Topping A90 Discrete headphone amplifier is here. As its name, A90 Discrete uses fully discrete components to redesign the NFCA module. A fully balanced architecture is achieved on the A90 Discrete with four built-in NFCA (Nested Feedback Composite Amplifier) Discrete modules, each using 39 transistors. Excellent DC and AC performance is delivered; by the improved Voltage Current hybrid feedback architecture in conjunction with UHGF (Ultra High Gain Feedback) technology. The Topping A90 Discrete can drive high impedance and low sensitivity headphones/IEMs because of the new design's better output capacity. Unparalleled distortion-free, and noise-free performance, are ensured by the paralleled ultra-low noise precision-matched transistors used in the design. The background of the Topping A90 Discrete is incredibly silent and dark, and the sound is quite natural as it can be. It has a very accurate, crisp bass response and a smooth top end. With this amplifier, the midrange comes through clearly and smoothly, allowing you to hear how a recording sounds. Experience music like never before and delve into pure sonic bliss with the all-new A90 Discrete.

A90 DISCRETE COUPLED WITH AN EXTENDER INPUT INTERFACE THAT CAN DRIVE THE MOST DEMANDING HEADPHONES WITH LOW DISTORTION

The engineers at Topping set out to create a powerful amplifier without distortion, typically associated with high power. A90 Discrete underwent numerous tests and prototypes to become the most reliable and effective headphone amplifier. The Topping A90 Discrete promises to deliver spectacular performance with low distortion while outputting high power. High output current and low output impedance will not have any unneeded consequences when driving low-impedance headphones. The high output voltage and current can readily drive high impedance headphones. The A90 Discrete can power a variety of headphones. In addition to the high output power, the A90 Discrete can maintain ultra-low distortion output power under a high power load. The A90 Discrete provides you with 1 x XLR and 1 x RCA stereo inputs, but when it works with an Ext90, they could enable a total of 4 x XLR and 2 x RCA stereo inputs. The 12V Trigger interface on the A90 Discrete can be configured for active control (Trigger out) or passive control (Trigger in). With only one easy-to-obtain 3.5mm to 3.5mm cable, the A90 Discrete can be turned on and off synchronously with other devices equipped with a 12V Trigger interface. With this setup, you can connect A90 Discrete to Topping U90 Professional Grade USB Audio Bridge, and you can form your desktop audio chain.

TOPPING A90 DISCRETE DOUBLES UP AS AN AMPLIFIER AND PRE-AMPLIFIER WITH A FULLY-FEATURED REMOTE CONTROL

The Topping A90 Discrete is not only able to drive the headphones but also serves as a preamp. When it is in preamp mode, you can get the same high performance as the headphone amp mode, and the 20 ohms SE and 40 ohms balanced output impedance are widely suitable for various power amplifiers. A90 Discrete can not only switch between the headphone amp (only output from the headphone jack) and the preamp (only output from RCA and XLR) but also support the output from all simultaneously. The full-featured remote control makes it more convenient for you to use. You can control various operations like Standby, Volume up, Switch to previous, input, Output channel switching, User setting, Headphone amp gain, Mute, OK button, Switch to next, input Volume down, User setting, and Brightness settings. The output volume or the input volume of an A90 Discrete can be programmed to be stored. When the output volume is stored, the A90 Discrete will immediately return to the previously used level when the same output is selected again. This design applies to the PRE (Pre-Amplifier), HPA (Headphone Amplifier), and PRE+HPA modes. When the input volume is stored, the A90 Discrete will remember the volume settings for each input separately and will automatically return to the previous volume setting the next time the same is selected.

NOTE: Press and hold the C1/C2 button for 3 seconds to save the current program (including input channel, output channel, volume and brightness), and "C1" or "C2" will be displayed after successfully saving. Short press the C1/C2 button to use the corresponding program.

FEATURES TWO-STEP GAIN SETTINGS, AN R2R VOLUME CONTROL KNOB, AND GLNTS TO REDUCE GROUND LOOP NOISE

The Topping A90 Discrete is a versatile balanced amplifier that not only power high impedance headphones but are super clean while powering low and high-sensitivity IEMs. This delivery of clean output power was possible as the A90 Discrete is a complete design overhaul that includes two-step gain settings. The A90 Discrete has two gain options, which are enough to cover a wide variety of headphones: low gain to drive the IEMs with high sensitivity and high to drive full-sized over-ear headphones. Combined with the 0.2uVrms ultra-low noise, even sensitive IEMs will not suffer from any noise. On balanced ports, the output power is 6db on low gain and 15.5dB on high. The output power through single-ended is 0dB on low and 9.5dB on high. The classic Topping A90 used a standard volume potentiometer. These often suffer from channel imbalance at low volumes, which makes listening to sensitive IEMs tough. To overcome this issue, Topping introduced a low gain setting on the A90 Discrete with an R2R volume controller, allowing you to set the volume knob for dialling in a suitable volume that doesn’t result in channel imbalance. These offer massive advantages over standard potentiometers, like outstanding THD+N, SNR, and well-balanced channels. A90 Discrete uses an R2R volume control composed of relays and resistor networks, bringing advantages of precise control, longevity, complete channel balanced and remote control. According to the customised settings volume can be set for the A90 Discrete to avoid a sudden loud burst after the power on/input switch. Ground loop noise may be encountered when multiple devices are powered in combination. A90 Discrete adds a Ground Loop Noise Terminator Switch (GLNTS) GND/LIFT to solve this problem. When in normal use, set it to GND and when ground loop noise is encountered, switch it to LIFT to eliminate ground loop noise.

EXQUISITE DESIGN FUSED WITH ACCESSORIES AND NUMEROUS INPUTS AND OUTPUTS FOR EASY CONNECTIVITY AND COMPATIBILITY

Topping has always strived to push the frontiers by developing products that combine stunning design and build quality. The Topping A90 Discrete comes with a remote, 6.35mm to 3.5mm adapter, AC cable, warranty card, and a user manual to get you started. It features numerous inputs and outputs for easy compatibility and connectivity. It includes a 4-pin XLR (External Line Return) balanced and a 4.4mm balanced headphone output jacks. It also features a single-ended 6.35mm headphone output jack which makes A90 Discrete compatible with most headphone terminations. The A90 Discrete includes single-ended RCA input and single-ended RCA output with balanced XLR input and XLR outputs.