Amplifier: ZEN&BOZ 2x10W + fan box

Speakers: BC-acoustique Hudson 4 ohm 91dB

Cd-player: Rotel 971

2pcs - 2x30V 350W

1pcs - 2x60V 50W

In order for the main boards not to suffer from interference I isolate them using a steal cover - not shown here

Second level - power suplies, main boards

A known sentence 
 you can never have enough heat sinks

All the parts - just before mounting

I never thought that the sound of music could give us pleasure and provide a cure...

Ever since I can remember I have always been an audio fan. I used to change my equipment every year. I quickly realized that there is a difference between two models of speakers, amps or cd-players. Unfortunately High-end models were, are and probably will always be above my financial possibilities.

On one of boring train trip I read an article about something special A-class amp. A Quick decision, and a large assortment of parts created the first version of my ZEN & BOZ. Just to find out if it is worth doing. The results were pretty good. I decided to build an amp working on a 4 ohm load and output with a 10W power. In my case it was enough. What I created was a 30 kg monster.

My project is based on the circuits from this web page. I didn't make any changes.

My Amp has a level structure:

1. transformers

2. the power supplies, main boards

All parts I bought are common and cost less than I thought.

The Heart of the amp - power supplies and main boards.

To have the possibility to run it on 4 ohm loads with twice the power I made 4 main boards which had their own power supplies. I connected the boards parallel in pairs, so than each pair formed a channel. Each channel is separated by metal cover. The pre-amp section is situated in the back of the amp (shorter connections).

The heat sinks aim is to prevent the eight mosfets from overheating. As usual they are not big enough. I made a special box and place it bellow the amp (as seen on the first photo). Separate transformer and two big fans placed inside are responsible for keeping the heat sinks cool. The whole box has sound isolation inside, lower voltage which comes to the fans make them really quite.

Without the fans temperature of the heat sinks was close to 75^oC. Now you can easily put your hands on it.

I started my adventure with the Pass amp in the middle of the year 2000. It took me over than 6 months to finish it. But my dream will have never come through if not for:

• my wife's patience

• my father's never ending help

• Mr Pass's good advice

To all those who are still in doubt - BEFORE YOU SAY ANYTHING JUST LISTEN TO THIS AMP.

For more information please write to me: marcin.obuchowicz@bauma.com.pl

or marcin_obuchowicz@poczta.onet.pl