TOPPING A90 Discrete Headphone Amp

Our best-selling amplifier 

“Mr. Clean.” “The Giant Killer.” “The Best Amp Ever.” These are a few of nicknames the TOPPING A90, our best-selling amplifier, has gained since its release. At its most basic level, it’s a balanced amp and pre-amp with tremendously clean and powerful output. At its broadest level, it’s become the benchmark by which all other solid state amplifiers below $1,000 are judged.

D for Discrete

The A90 Discrete, or A90D, is an upgraded version of the groundbreaking A90. As its name suggests, the A90D uses fully discrete components in a complete redesign of the A90 NFCA module. Four discrete NFCA modules using 39 transistors each form the fully balanced amp architecture. The matched precision transistors ensure unparalleled distortion and noise performance. 

Say goodbye to ground loop noise

When multiple pieces of equipment are used in conjunction, ground loop noise can occur. Ground loop noise most often manifests as a buzzing or humming sound, which is capable of being loud enough to damage speakers. Although it’s known to happen most often in single-ended feeds, it can happen in balanced feeds, too.

The A90D solves this issue with a GND/LIFT switch. When in normal use, set the switch to GND. If you encounter ground loop noise, set the switch to LIFT, which will change the ground point of the A90D from its chassis to the equipment it’s connected to, eliminating the noise. 

Pre-amp mode

With the A90D in pre-amp mode, connect a power amplifier to drive bookshelf, desktop, or floor speakers. You can also connect the A90D to the D90SE/LE DAC in pre-amp mode to create a complete high-end sound system. And with the included remote control, you can control it all from the comfort of your couch. 

12V trigger

Wouldn’t it be nice if every time you turned on the A90D, the TOPPING LA90 came on automatically, or vice versa? That’s possible thanks to the A90D’s 12V trigger interface. Set it to active (trigger out) or passive (trigger in), and it can be turned on and off synchronously with other devices equipped with a 12V trigger interface. 

R2R volume control

The A90D uses an R2R volume control composed of relays and resistor networks, bringing the advantages of precise control, longevity, and complete channel balance. 

A90D Product highlights

• Headamp/pre-amp
• NFCA discrete modules
• 9800mW x2 output power
• Outputs: 4-pin XLR, 4.4 balanced, 6.35mm SE
• R2R relay volume control
• Ground loop noise terminator
• 12V trigger interface
• 2 gain settings
• <0.000055% THD+N
• 145dB DNR