I'v finished 2 channels of API-like preamps.
Here are some photos:
My own pcb's, 75101APC input transformers, CMOQ-2S outputs,
and opamps made from fabio's 2.5.2.0BC boards...
I did some recordings for comparing the 2.5.2.0BC with the original 2520 opamp (black, new one)...
I'v used a dynamic mic with Y-cable that goes into both channels,
and placed an original API opamp in one of the channels.
Both channels were calibrated to the exact level.
Original API opamp (acoustic):
http://www.freewebs.com/upa-audio/API_ACOUSTIC.wav
2.5.2.0BC (acoustic):
http://www.freewebs.com/upa-audio/UPA_ACOUSTIC.wav
Original API opamp (electric):
http://www.freewebs.com/upa-audio/API_ELECTRIC.wav
2.5.2.0BC (electric):
http://www.freewebs.com/upa-audio/UPA_ELECTRIC.wav
Comments are welcomed....
Udi.
Here are some photos:
My own pcb's, 75101APC input transformers, CMOQ-2S outputs,
and opamps made from fabio's 2.5.2.0BC boards...
I did some recordings for comparing the 2.5.2.0BC with the original 2520 opamp (black, new one)...
I'v used a dynamic mic with Y-cable that goes into both channels,
and placed an original API opamp in one of the channels.
Both channels were calibrated to the exact level.
Original API opamp (acoustic):
http://www.freewebs.com/upa-audio/API_ACOUSTIC.wav
2.5.2.0BC (acoustic):
http://www.freewebs.com/upa-audio/UPA_ACOUSTIC.wav
Original API opamp (electric):
http://www.freewebs.com/upa-audio/API_ELECTRIC.wav
2.5.2.0BC (electric):
http://www.freewebs.com/upa-audio/UPA_ELECTRIC.wav
Comments are welcomed....
Udi.