av reciever with a problem can you guys help?

[Kanifee]

hi fellas i come to you with a query and hopefully for a simple solution.
i have the chance of a philips av receiver cheap only problem is it has developed a fault.
the fault is that when it hits high volume it has a tenancy to cut off the machine just switches off and then when you press the power button its comes straight back on, now im informed that at low level this doesn't occur just at high volume so to me it sounds like a safety cut off i used to have a sony receiver that did it then i realized the unit has been moved and wires from the speaker to the terminal on the back of the unit were shorting on something then when i fixed the wires it worked fine.
now i assume the fella has taken the time to sort through things like that im unsure though if he has tried different speakers what do you guys think?

 

[fizzy]

Are the speakers you are using ones that were supplied with the amp, or ones you added yourself? Are they the correct impedance rating - such as 8 or 16 ohm - for the amp? Should state required range on the back of the amp, and the speaker rating on the back of the speakers.

May be worth checking that you have correct polarity on each speaker connection. + to + and - to - on both speakers. Its pretty easy to get them crossed on one speaker if the cable is not marked in anyway at all. (think that makes them go "out of phase"?)

The amp cutting off at high volume sound like its either some sort of overload protection kicking in (hence the questions above), or something failing that can't take the top end power requirements. Also are all the air vents on the unit clear from obstructions? If it uses any form of active cooling (such as a small fan) may be worth seeing if you can hear it working or not.

The only time I would suspect a loose connection is if the unit is getting vibration from somewhere.... and as there are no moving parts in the amp (except the volume control ) then this must be an external source. Where are your speakers - are they close to or resting on your amp?

If everything checks out then it sounds like there something potentially faulty with the unit itself.

Anyway - hope all my waffling helps a bit, and I'm not just teaching you how to suck eggs/going over stuff you already know.