Miscellaneous Projects

About me
My name is Norbert Kulcsar, from Hungary and I would like to present you some of my Pass DIY project . (Sorry for the bad quality pics, but I have only a very simple digi cam.) Last year I finished and became a proud owner of an excellent amp the A5! It is an exact copy of the original electrical layout published on Pass Labs website, with a little more PSU capacitance.

The amplifier circuit itself was done using Kristijan Kljucaric's PCBs, which made things comparatively easy. These PCBs are laid out logically, they are very high quality and they also come with a helpful set of tips on mounting the fets and on which parts to use. The amp is operating faultless since the first turn on. Temperature on the heatsinks after 1 hour operating is around 55 degrees Celsius. Offset voltage under 10mV! No turn on "thump" or any other noise, the amp is deadly quiet on idle. The amp's weight is 15 kg. I use the amp with the BOSOZ, what is an excellent preamp! It has absolutely natural and detailed sound! The sound of Amplifier5: it 's just marvelous! The overall performance is very good, comparable to any conventional HI-FI solid state or valve amp and it is outperforming also some "exotic" SET amps!!! The tonal character is very musical and "tube like". The Amplifier5 presents a sort of liquidity and easiness to the sound, making it very natural and full with life. Transparent, detailed and micro dynamics are awesome. Soundstage just "exploded" all around the room. Amplifier gives an amazing powerful bass (absolute controlled) I never heard something better than that. I have to say it is really a High End Beast! And here is the part list: - 19" case made out of 5mm aluminum sheets - 1 transformer with 2x28V 630VA - capacitors 4x 60.000 µF/ 75V Philips -2x 4 mH inductor - 6x irfp240 matched pair of Mosfet per channel, from Kristijan Kljucaric -10R/6W thermistor - 2 blue led ) At last thanks to Mr. Pass and the Pass Labs crew for sharing their knowledge and to Kristijan Kljucaric and everyone on DIYaudio forum for help to build this wonderful amp! Best Regards: Norbert