Salas hotrodded blue DCB1 build

hmmmm...think something went wrong. With that small DC offset...the main amplifier goes into DC-protection.

Could it be the problem that the output of a laptop has some DC on it's output???

Tested it also with a source that has coupling caps for sure. Amplifier goes in protection mode either.

Checking for a mistake tomorow:)
 
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DCB1 does not block DC errors.
If your Power amplifier is also DC coupled then that too will not tolerate DC errors.

Do you want to play music or go round in circles repairing amplifiers and speakers?

The consequences of DC coupled throughout a system are dire.

Make informed choices before building.
 
DCB1 does not block DC errors.
If your Power amplifier is also DC coupled then that too will not tolerate DC errors.

Do you want to play music or go round in circles repairing amplifiers and speakers?

The consequences of DC coupled throughout a system are dire.

Make informed choices before building.

That is the strange thing....my amplifier has coupling caps on its input...so it is AC coupled.
 
There is nothing inherent to produce noises or instability. We never had such reports in the threads. Just test it long enough as finally built with your likely source and amp on cheap speakers to make sure they are a stable combo.

Indeed. Couldn't find anything. I will describe my situation as good as possible.
The main amplifier is a Velleman K4020. As I can see in the schematics...there are input caps of 2.2µF.

On the DCB1...for Left and Right channel...only one pin and the pin of "the swiper" contact were connected. The pins of the attenuator that goes to left two pcb holes (top view...pointing potmeter to you) were not connected.

Smoke came out of the tweeter. So Hopefully this will not happen any more to someone else. Lucky me it was only a cost of 18 euro.

Is it also possible that the main amplifier went into parastic oscillation by doing a faulty wiring at the DCB1 and therefore blowned the tweeter?
 
The problem was .. a forgotten mass lead of the attenuator. Gave HF glitches...went through the AC-coupled amplifier...offcourse...and burned a tweeter.

Error found.
I'm so happy with my DCB1!!! thank you all who have developed this and tweaked this. This is the best thing I've ever heard!! I kneel for you guys :)