[pensiero]

Hello, in my temporary apartment there is an AMP (Braun A2), currently connected to a pair of speakers (output), a record player and a projector (input). Overall the AMP works fine, however from time to time one of two speakers doesn't emit any sound for the first 5/10mins.

So, the AMP is quite old, and I'm not sure it's in perfect condition for the reason above.

Having said so, I wanted to buy a new pair of headphones (Hifiman Arya, planar magnetic). If the AMP is actually damaged, can a damaged AMP damage a pair of headphones?

Thank you

 

[Roseval]

AMPs can damage drivers.
However as the speakers still work it is probably something like a bad contact, sticky relay, etc.
Make sure it is not a bad contact in the speaker by swapping the channels.

Even if everything works fine, this won’t guarantee that the headphone section is functioning properly.
Before you fry an Arya, get a adapter and plug in the earbuds the come with your phone or anything cheap you have lying around. If they survive, you can connect a $$$ headphone.

 

[pensiero]

Thanks, I tried with a pair of old headphones and they work overall fine, however the right channel doesn't work either. I guess there is some defect in the AMP, need to discover what exactly.

 

[tomb]

I just checked the Braun A2 schematic from the service manual on hifiengine.com. The headphone output is definitely connected directly to the speaker outputs, through a dropping resistor network. I can't tell a lot more beyond the schematic, because it's all in German.

One thing you should always do with an old amp or receiver … check for voltage offset on the outputs. Many, if not most, old amps and receivers (new ones, too) have specific adjustments for zeroing out offset in the service manual. There are definitely trim pots shown in the schematic, so there's a strong chance this requirement exists with the Braun A2.

There could be a capacitor going bad or something else interfering with the relays that prevent the signal from coming on line. The drift could be such that there's significant offset until the circuit levels out enough to allow the relays to work. Just guessing … However, it appears from the service manual that the Braun A2 was made in 1985. That's about 35 years. Most experts agree that re-capping is needed after 30 years or more.

Again, you should always check the output for voltage offset on any old receiver or amp. It could save the rest of your equipment from damage. If you're not familiar with how to do this or feel comfortable looking up the service manual on hifiengine.com and making the adjustments yourself, find a friend or a service tech who can provide this service for you. That, or stick to new equipment for your hi-fi needs.

 

[pensiero]

Thanks @tomb for the exhaustive explanation. I agree with you, it's 35 years old and I guess it would be worth let an expert check it. I guess for now I would play safe, buy a Topping A30/D30 stack (which I understood is one the best budget DAC/AMP here in Germany, but this I guess is another topic) and use it with the Arya