TOPPING A90 DISCRETE Discrete Balanced Headphone Amplifier Preamplifier Silver

Discrete NFCA amplifier

Topping's A90 Discrete features a Nested Feedback Composite Amplifier (NFCA) stage based on the use of discrete components. The four integrated discrete NFCA modules each use 39 transistors in a balanced design. The optimized hybrid voltage/current feedback architecture and Ultra High Gain Feedback (UHGF) technology provide excellent DC and AC performance. With this new design, the A90 Discrete benefits from high output power, allowing it to accompany both high-sensitivity headphones and high-impedance headphones effortlessly. Precisely matched ultra-low noise transistors connected in parallel ensure extremely low noise and distortion.

Integrated preamplifier

In addition to its headphone amplifier section, the A90 Discrete includes a preamp circuit. In preamp mode, you get the same performance as in headphone amplifier mode. The single-ended 20Ω and balanced 40Ω outputs allow to accompany many amplifiers. Moreover the two modes can be used simultaneously and the remote control allows to access each function easily.

Specifications
Product type	Headphone amplifier Preamplifier
Inputs	1x Balanced stereo XLR 1x Single-ended stereo RCA
Outputs	1x Balanced stereo XLR 1x Single-ended stereo RCA 1x Balanced Jack 4.4mm headphone output 1xBalanced XLR 4 pins headphone output 1x Single-ended Jack 6.35mm headphone output

Specifications

Product type

Headphone amplifier
Preamplifier

Inputs

1x Balanced stereo XLR
1x Single-ended stereo RCA

Outputs

1x Balanced stereo XLR
1x Single-ended stereo RCA
1x Balanced Jack 4.4mm headphone output
1xBalanced XLR 4 pins headphone output
1x Single-ended Jack 6.35mm headphone output

Discrete headphone amplifier performance
	SE Input/ SE Output	BAL Input / SE Output	SE Input / BAL Output	BAL Input / BAL Output
THD+N @ 1kHz (A-Weighting)	< 0.000065% @ 500mW, 32Ω	< 0.00008% @ 500mW, 32Ω	< 0.000065% @ 2000mW, 32Ω	< 0.00008% @ 2000mW, 32Ω
< 0.000055% @ 80mW, 300Ω	< 0.00006% @ 80mW, 300Ω	< 0.000055% @ 320mW, 300Ω	< 0.00006% @ 500mW, 300Ω
THD+N @ 20Hz-20kHz (90kBW)	< 0.0003% @ 500mW, 32Ω	< 0.0003% @ 500mW, 32Ω	< 0.0006% @ 2000mW, 32Ω	< 0.0006% @ 2000mW, 32Ω
< 0.00025% @ 80mW, 300Ω	< 0.00025% @ 80mW, 300Ω	< 0.00025% @ 320mW, 300Ω	< 0.00025% @ 320mW, 300Ω
SNR @ Max Out, 1kHz (A-Weighting)	141dB	137dB	145dB	138dB
Dynamic range @ 1kHz (A-Weighting)	141dB	137dB	145dB	138dB
Frequency response	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)
Output level	25Vpp	25Vpp	49Vpp	49Vpp
Measured noise level @ A-Weighting	< 0.7µVrms @ G=L	< 0.7µVrms @ G=L	< 1µVrms @ G=L	< 1µVrms @ G=L
< 1.1µVrms @ G=H	< 1.1µVrms @ G=H	< 1.8µVrms @ G=H	< 1.8µVrms @ G=H
Actual noise level @ A-Weighting	< 0.2µVrms @ G=L	< 0.2µVrms @ G=L	< 0.7µVrms @ G=L	< 0.7µVrms @ G=L
< 0.6µVrms @ G=H	< 0.6µVrms @ G=H	< 1.6µVrms @ G=H	< 1.6µVrms @ G=H
Channel crosstalk @ 1kHz	-107dB	-105dB	-116dB	-113dB
Input sensitivity	9.1Vrms @ G=L	9.3Vrms % @ G=L	9.1Vrms % @ G=L	9.3Vrms % @ G=L
3Vrms @ G=H	3Vrms @ G=H	3Vrms @ G=H	3Vrms @ G=H
Gain	0db @ G=L	-0.2dB @ G=L	6dB @ G=L	5.8dB @ G=L
9.5dB @ G=H	9.3dB @ G=H	15.5dB @ G=H	15.3dB @ G=H
Output power	< 0.1Ω	< 0.1Ω	< 0.2Ω	< 0.2Ω
Output impedance	2x 3300mW @ 16Ω, THD+N < 0.1% 2x 2000mW @ 32Ω, THD+N < 0.1% 2x 1100mW @ 64Ω, THD+N < 0.1% 2x 250mW @ 300Ω, THD+N < 0.1%	2x 9800mW @ 16Ω, THD+N < 0.1% 2x 6700mW @ 32Ω, THD+N < 0.1% 2x 4000mW @ 64Ω, THD+N < 0.1% 2x 1000mW @ 300Ω, THD+N < 0.1% 2x 500mW @ 600Ω, THD+N < 0.1%
Load impedance	> 8Ω

Discrete headphone amplifier performance

SE Input/ SE Output

BAL Input / SE Output

SE Input / BAL Output

BAL Input / BAL Output

THD+N @ 1kHz (A-Weighting)

< 0.000065% @ 500mW, 32Ω

< 0.00008% @ 500mW, 32Ω

< 0.000065% @ 2000mW, 32Ω

< 0.00008% @ 2000mW, 32Ω

< 0.000055% @ 80mW, 300Ω

< 0.00006% @ 80mW, 300Ω

< 0.000055% @ 320mW, 300Ω

< 0.00006% @ 500mW, 300Ω

THD+N @ 20Hz-20kHz (90kBW)

< 0.0003% @ 500mW, 32Ω

< 0.0006% @ 2000mW, 32Ω

< 0.00025% @ 80mW, 300Ω

< 0.00025% @ 320mW, 300Ω

SNR @ Max Out, 1kHz (A-Weighting)

141dB

137dB

145dB

138dB

Dynamic range @ 1kHz (A-Weighting)

141dB

137dB

145dB

138dB

Frequency response

20Hz-40kHz (±0.1dB)

Output level

25Vpp

49Vpp

Measured noise level @ A-Weighting

< 0.7µVrms @ G=L

< 1µVrms @ G=L

< 1.1µVrms @ G=H

< 1.8µVrms @ G=H

Actual noise level @ A-Weighting

< 0.2µVrms @ G=L

< 0.7µVrms @ G=L

< 0.6µVrms @ G=H

< 1.6µVrms @ G=H

Channel crosstalk @ 1kHz

-107dB

-105dB

-116dB

-113dB

Input sensitivity

9.1Vrms @ G=L

9.3Vrms % @ G=L

9.1Vrms % @ G=L

9.3Vrms % @ G=L

3Vrms @ G=H

Gain

0db @ G=L

-0.2dB @ G=L

6dB @ G=L

5.8dB @ G=L

9.5dB @ G=H

9.3dB @ G=H

15.5dB @ G=H

15.3dB @ G=H

Output power

< 0.1Ω

< 0.2Ω

Output impedance

2x 3300mW @ 16Ω, THD+N < 0.1%
2x 2000mW @ 32Ω, THD+N < 0.1%
2x 1100mW @ 64Ω, THD+N < 0.1%
2x 250mW @ 300Ω, THD+N < 0.1%

2x 9800mW @ 16Ω, THD+N < 0.1%
2x 6700mW @ 32Ω, THD+N < 0.1%
2x 4000mW @ 64Ω, THD+N < 0.1%
2x 1000mW @ 300Ω, THD+N < 0.1%
2x 500mW @ 600Ω, THD+N < 0.1%

Load impedance

> 8Ω

Discrete preamplifier performances
	SE Input / SE Output	BAL Input / SE Output	SE Input / BAL Output	BAL Input / BAL Output
THD+N @ 1kHz (A-Weighting)	< 0.000055%	< 0.00006%	< 0.000055%	< 0.00006%
THD+N @ 20Hz-20kHz (90kBW)	< 0.00025%	< 0.00025%	< 0.00025%	< 0.00025%
SNR @ 1kHz (A-Weighting)	141dB	137dB	145dB	138dB
Dynamic range@ 1kHz (A-Weighting)	141dB	137dB	145dB	138dB
Frequency response	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)	20Hz-40kHz (±0.1dB)
Output level	25Vpp	25Vpp	49Vpp	49Vpp
Measured noise level @ A-Weighting	< 0.7µVrms @ G=L	< 0.7µVrms @ G=L	< 1µVrms @ G=L	< 1µVrms @ G=L
< 1.1µVrms @ G=H	< 1.1µVrms @ G=H	< 1.8µVrms @ G=H	< 1.8µVrms @ G=H
Actual noise level @ A-Weighting	< 0.2µVrms @ G=L	< 0.2µVrms @ G=L	< 0.7µVrms @ G=L	< 0.7µVrms @ G=L
< 0.6µVrms @ G=H	< 0.6µVrms @ G=H	< 1.6µVrms @ G=H	< 1.6µVrms @ G=H
Channel crosstalk @ 1kHz	-107dB	-105dB	-116dB	-113dB
Input sensitivity	9.1Vrms @ G=L	9.3Vrms % @ G=L	9.1Vrms % @ G=L	9.3Vrms % @ G=L
3Vrms @ G=H	3Vrms @ G=H	3Vrms @ G=H	3Vrms @ G=H
Gain	0db @ G=L	-0.2dB @ G=L	6dB @ G=L	5.8dB @ G=L
9.5dB @ G=H	9.3dB @ G=H	15.5dB @ G=H	15.3dB @ G=H
Load impedance	20Ω	20Ω	20Ω	20Ω

Discrete preamplifier performances

SE Input / SE Output

BAL Input / SE Output

SE Input / BAL Output

BAL Input / BAL Output

THD+N @ 1kHz (A-Weighting)

< 0.000055%

< 0.00006%

< 0.000055%

< 0.00006%

THD+N @ 20Hz-20kHz (90kBW)

< 0.00025%

SNR @ 1kHz (A-Weighting)

141dB

137dB

145dB

138dB

Dynamic range@ 1kHz (A-Weighting)

141dB

137dB

145dB

138dB

Frequency response

20Hz-40kHz (±0.1dB)

Output level

25Vpp

49Vpp

Measured noise level @ A-Weighting

< 0.7µVrms @ G=L

< 1µVrms @ G=L

< 1.1µVrms @ G=H

< 1.8µVrms @ G=H

Actual noise level @ A-Weighting

< 0.2µVrms @ G=L

< 0.7µVrms @ G=L

< 0.6µVrms @ G=H

< 1.6µVrms @ G=H

Channel crosstalk @ 1kHz

-107dB

-105dB

-116dB

-113dB

Input sensitivity

9.1Vrms @ G=L

9.3Vrms % @ G=L

9.1Vrms % @ G=L

9.3Vrms % @ G=L

3Vrms @ G=H

Gain

0db @ G=L

-0.2dB @ G=L

6dB @ G=L

5.8dB @ G=L

9.5dB @ G=H

9.3dB @ G=H

15.5dB @ G=H

15.3dB @ G=H

Load impedance

20Ω

General
Supply voltage	100-240VAC 50/60Hz
Dimensions	222 x 160 x 45mm
Color	Silver
Package	1x Topping A90 Discrete 1x Remote control 1x Powre cable 1x Male Jack 6.35mm to female Jack 3.5mm adapter

General

Supply voltage

100-240VAC 50/60Hz

Dimensions

222 x 160 x 45mm

Color

Silver

Package

1x Topping A90 Discrete
1x Remote control
1x Powre cable
1x Male Jack 6.35mm to female Jack 3.5mm adapter

Input	XLR
Input	RCA
Output	Jack 6.35mm
Output	XLR
Output	Jack 4.4mm
Output	RCA
Color	Silver
Class	Class A / AB
Remote Control	Yes