Ingvar Ahlberg
AVForums Grandmaster
Wanted to play a few records yesterday, started with Jake Xerxes Fussell, Good and Green again, and noticed, after a short while, that there was very limited LF output from the right speaker, went there to check, put the ear to the drivers, noticed then that the LF drivers were pulled back almost to the bottoming point, still playing but with far lower level so checked with a multimeter and there was -12VDC at the speaker terminals, can not be a power amp failure, would have been around 70VDC, so switch off,
disconnect cables from pre amp and switch on again, a time consuming routine with the Electro Research power amp, and zero voltage on the same terminals.
So the culprit is the GAS Thaedra that has decided to put a few volts, volume dependent, on the output terminals, manufactured somewhere 1976-1978 it´s not even 50 Years, should not fail already!
As the DC is following the volume control I know where the problem is and should not be very hard to fix but the Thaedra is a total PITA to disasemble and also to put back together so what to do?
Will repair of of course but probably must buy another pre amp to use in the meantime, where to go, ARC SP3-A, SP8, APT Holman, Threshold Fet One, Precision Fidelity, Sentec SCA1 or any other ideas?
Ingvar
disconnect cables from pre amp and switch on again, a time consuming routine with the Electro Research power amp, and zero voltage on the same terminals.
So the culprit is the GAS Thaedra that has decided to put a few volts, volume dependent, on the output terminals, manufactured somewhere 1976-1978 it´s not even 50 Years, should not fail already!
As the DC is following the volume control I know where the problem is and should not be very hard to fix but the Thaedra is a total PITA to disasemble and also to put back together so what to do?
Will repair of of course but probably must buy another pre amp to use in the meantime, where to go, ARC SP3-A, SP8, APT Holman, Threshold Fet One, Precision Fidelity, Sentec SCA1 or any other ideas?
Ingvar
