I've built quite a few different amplifiers over the years and was curious if any of you on here also have. A few that I've done are the Krell KSA-50 MK2 and the KSA-100 MK2 and a number of pass labs Aleph circuits including the Aleph 30 and A pair of Aleph 2 mono blocks. Till I acquired the PL-700 I've built only class A power amps over the last 15 years. I also repair lots of amplifiers... QSC and Crown as part of my job as a Cinema Technician. I've included a few pictures of past projects.
Mark
One of a pair of Pass Aleph 2 Monoblocks before the front panels and top covers were put on. 100 watts RMS into 8 ohms, 150 into 4 ohms. Idle current is about 4.5 amps per rail (higher than the factory amplifiers.)
Krell KSA-50 MK2: Our version has two extra output devices per channel and can produce 70 watts per channel in Class A and then up to 90 watts in class AB. Power output doubles each time impedance is halved down to 2 ohms. Power transformer is Dual Secondary 1.2KVA!
KSA-100 MK-2: This was the prototype proof driver board for a group buy at another forum. The driver board is a small Class A power amp in its own right.
100 ha square wave through the driver board. Looks exactly the same with the output stage connected.
Gold plated KSA-100 driver boards I had made for myself when we did the group buy. This is my next amp project. I never took the KSA-100 clone beyond prototype to prove it worked with the new fets we had to use in place of the obsolete VPN fets... The board was designed by an electrical engineer in South Africa for the group buy.
Aleph 30, two complete channels, Gold plated PCB.
Mark
One of a pair of Pass Aleph 2 Monoblocks before the front panels and top covers were put on. 100 watts RMS into 8 ohms, 150 into 4 ohms. Idle current is about 4.5 amps per rail (higher than the factory amplifiers.)
Krell KSA-50 MK2: Our version has two extra output devices per channel and can produce 70 watts per channel in Class A and then up to 90 watts in class AB. Power output doubles each time impedance is halved down to 2 ohms. Power transformer is Dual Secondary 1.2KVA!
KSA-100 MK-2: This was the prototype proof driver board for a group buy at another forum. The driver board is a small Class A power amp in its own right.
100 ha square wave through the driver board. Looks exactly the same with the output stage connected.
Gold plated KSA-100 driver boards I had made for myself when we did the group buy. This is my next amp project. I never took the KSA-100 clone beyond prototype to prove it worked with the new fets we had to use in place of the obsolete VPN fets... The board was designed by an electrical engineer in South Africa for the group buy.
Aleph 30, two complete channels, Gold plated PCB.
