High End 225W Monoblock power amplifier

Driving a loudspeaker system with a power amplifier is one thing, however actually precisely controlling the drivers in the system is something else. 

The moving element in a loudspeaker driver, usually a voice coil, is actually a linear moving motor with a membrane attached to it. This motor has to be moved backward and forward in a way that exactly follows the waveform that is applied to it so fast pushing, stopping and pulling with great force.

The mass of the voice coil assembly and the membrane coupled with the air moved by the membrane have to be pulled and pushed with energy coming from the amplifier and this can require a lot of energy that the amplifier system must be able to supply at all time. The better the amplifier is capable of fulfilling this task the better the sound reproduction will be.

We have designed the PWA01 amplifier module do exactly that and combined with the correct power supply it is capable to drive the most demanding loudspeaker system with ease.

Although the specifications of this amplifier are very good, in the design stage more attention has been given to the sound of this product by listening tests and selecting the best sounding components rather than by measuring and developing to the best electrical properties. This creates a particularly good sounding amplifier that can compete with many very expensive products in the High-End market. The module is build on an 5mm aluminum plate that is mounted to a large and heavy 200 x 150 x 40 mm heat-sink.

So the base of this project is the Audio products very powerful PWA01 power amplifier module that is based on an all transistor vintage amplifier design build with the latest up-to-date modern components like dual Sanken driver transistors, Toshiba power transistors and Nichicon audio-grade capacitors. 



Some specifications

RMS power:
225W 4 Ohm 5-50.000 Hz
130W 8 Ohm 5-50.000 Hz

Dynamic power:
475W 4 Ohm 20-20.000 Hz


Next to the power amplifier module it incorporates an audiophile power supply PSP01 from Audio products with a large capacitor bank of 120.000 µF, 60.000 µF per voltage rail and a 2 x 35V 9A 625VA torroidal power transformer. 



This power supply is able to deliver very high currents instantaneously to have the power amplifier control even the most difficult loudspeaker system.


To control this all an Audio products power supply controller IRC01C is used. This controller has a mains filter to reject EMI and enables you to switch the power on or off with a single ‘illuminated’ push button. It also has an input to detect incoming audio signals and switch the power supply on or off depending on signal input to the amplifier. Next to this the controller accepts 12V trigger signals from the connected pre-amplifier to switch the power on and off.