I've always been a huge fan of Sunn amps (mostly the tube models) and I've owned quite few Sunn Coliseums in the past and had another mint one about 8 years ago. Here's pic of it:
IMO, it didn't really sound as good a I remembered, lacking low end, so I sold it.
About 4 years ago I decided to build the preamp of one in pedal form using the original factory schematic with original vintage transistors.
the hardest part was getting the power supply circuit solved for it as it required a lot of different voltages as well as a lot of filtering. With Frank Appleton of FEALABS help, i finally got it sorted and the result was awesome. It did require a 28 volt power supply (wall wart type) with a lot of filtering on another PCB to obtain the +28 +23 and -15 volts for it. IMO, it sounds a lot better than the actual head.
Here's a couple of pics of the pedal:
gut shot:
It was a pretty daunting task but I'm glad that I finally got it right and it was worth it.
IMO, it didn't really sound as good a I remembered, lacking low end, so I sold it.
About 4 years ago I decided to build the preamp of one in pedal form using the original factory schematic with original vintage transistors.
the hardest part was getting the power supply circuit solved for it as it required a lot of different voltages as well as a lot of filtering. With Frank Appleton of FEALABS help, i finally got it sorted and the result was awesome. It did require a 28 volt power supply (wall wart type) with a lot of filtering on another PCB to obtain the +28 +23 and -15 volts for it. IMO, it sounds a lot better than the actual head.
Here's a couple of pics of the pedal:
gut shot:
It was a pretty daunting task but I'm glad that I finally got it right and it was worth it.