511 Stereo
soulution 501 Monoamplifiers


soulution 511 stereo amplifier

Precision, stability and velocity...


... just a razor-thin fraction behind our reference designs of Series7, this was the design goal we have set for the 511 stereo amplifier. The 511 is equipped with the same "switched-mode" power supply technology, optimized for audiophile applications, as our series7 products. Additionally it is optimized for shortest "signal paths" for the music signal but as well for shortest paths and optimal flow of the current supplying the amplifier stages. Get inspired by the uncompromising music playback and enjoy the diversity and natural beauty of the music. A sound experience, of which everyone will be enchanted.

Convince yourself!


Key Features

- "Switched Mode" power supply (4 x 600VA ) optimized for use in audio amplifiers
- more than 500'000 µFarad of storage capacitance in the power supply
- Peak current rating of more than 60A
- versatile: stereo-, mono- und dual-mode
- Impulse power rating> 3'000 Watt (stereo/dual), > 6'000 Watt (mono)



Operating modes

The 511 stereo-amplifier can be used in three different setups:
- Stereo-mode: 140W @ 8Ω, 280W @ 4Ω, 560W @ 2Ω per channel
- Dual-mode: 140W @ 8Ω, 280W @ 4Ω, 560W @ 2Ω per channel
- Mono-mode: 560W @ 8Ω, 1'120W @ 4Ω, 2'000W @ 2Ω

The operating mode can be changed in the menu functions of the 511 stereo amplifier.



The amplification circuit similar to the technology used for the 711 and 701 amplifiers. At its core is a proprietary voltage amplification stage that consists of linearized amplifiers operating up to a cut-off frequency of 80MHz. Current amplification is done in three stages, each using a very small and thus almost linear operating range. The high Class A operation supplemented by 500,000µF of storage capacitance in the power supply results in a nearly infinite impulse response. Massive copper bars on the amplifier board and to the speaker terminals ensure that all the power of the 511stereo amplifier is available to drive the speaker. This ensures the 511 does not get the plaything of the loudspeakers, but controls them with the appropriate precision, power and velocity asked for by the music signal. High-precision idle current management ensures optimal Class A operation for all conditions, without requiring any readjustment in the music signal. Optimal sound is thereby guaranteed immediately from switch on.


Power supply

A total of 10 power supplies - optimized for each function - feed the 511 stereo amplifier. Circuitry that does not process audio signals should not be able to influence them. Therefore those supplying the digital and audio circuits are electrically isolated from each other by optocouplers. Four cutting-edge switched-mode power supplies combined with more than 500'000 µFarad of storage capacitance deliver 2,400W of audiophile quality power. They feature high performance filtering at the input and output, and six linear, high speed, ultra low noise voltage regulators to deliver considerably more stable power than any conventional, transformer-based technology.



Control circuits that protect the 511 stereo amplifier against RF or DC signals at the input, and short circuits at the output ensure safe operation in all situations. The input level is also monitored continuously. In case a malfunction is detected the 511 stereo-amplifier is muted and will automatically power down.



The 511 stereo amplifier is operated via push buttons and a rotary control on the front panel. It can be switched on remotely with other soulution devices via the LINK system.



Analogue inputs:
- 1 x balanced input (XLR)

Analogue outputs:
- 1 x balanced output (XLR)
- 1 pair speaker binding posts

- 1 x RJ45





THD vs. Power:

The diagram shows the power measurement into an 8Ω load. In contrast to other power amplifiers, distortions remain on a minimal level over the entire power bandwidth. Only once the power limit is reach and the soft-clip power limiter kicks-in the distortion starts to increase.

soulution 511 Stereoamplifiers: THD vs. Power
THD vs. Power

Fast Fourier Transfer (FFT)

Measurement for a 1kHz sine signal with 50 watts output power into an 8Ω load. All distortion components are below -115dBr and thus over 550,000 times smaller than the music signal.

soulution 511 Stereomplifiers: Fast Fourier Transfer (FFT)
Fast Fourier Transfer (FFT)

Frequency response

Gain at 100kHz is reduced by less than 0.1dB. The -3dB limit is only reached at 800kHz.

Frequency response




Stereo/Dual Mode

Mono Mode


Audio 2× 140 W @ 8Ω 560 W @ 8Ω
2 ×280 W @ 4Ω 1'120 W @ 4Ω
2 ×560 W @ 2Ω 2'000 W @ 2Ω
Standby consumption <0.5 W <0.5 W
Idle consumption 150-200 W 150-200 W


Impedance XLR 2 XLR 2
Sensitivity 1.55 Vrms 1.55 Vrms


Voltage max. 35 Vrms 70 Vrms
Current max >60 A >60 A
Impuls rating >2×3'000 W >6'000 W
Gain +26 dB +32 dB
Frequency response DC-800 kHz DC-1.6 MHz
Settling time 900 ns 450 ns
Distortion (THD+N) @ 1kHz <0.004 % <0.0004 %
Signal to Noise (SNR) @ 1kHz >107 dB >101 dB
Damping factor @100kHz > 10'000   > 5'000  


width x height x depth 442 x 265 x 448 mm 442 x 265 x 448 mm
weight 32 kg 32 kg