Audiolab 8000a upgrade capacitors etc

[toyota man]

Hi all A little while ago I bought my son an Audiolab 8000a amp from the bay I used it on my system and while I noticed a slight thud when I first turned it on it worked very well . Iwas round his yesterday and after we had been listening for a couple of hours he turned everything off and the amp made a sort of sqeeking sound that slowley faded I think though I dont realy know that this maybe a capacitor problem any advice on which capacitors it might be ? and also a low volumes you lose one channel the amp works very well at normal listenong levels but you loose a channelat low levels I am fairley hany with a soldering iron and can read circuit diagrams many thanks for any advice :cheers:

 

[toyota man]

Any ideas hopefully some electronics wizz will have had there sunday lie in and be able to help with this one please and thank you

 

[toyota man]

Hello is there anbody out there

 

[shafesk]

can't help much but heres a link to a service manual up for sale http://www.ebay.com/itm/Audiolab-8000-series-Service-Manuals-Parts-List-S-P-Q-M-CD-AV-X7-/170899484519?pt=Vintage_Electronics_R2&hash=item27ca672f67

 

[toyota man]

can't help much but heres a link to a service manual up for sale http://www.ebay.com/itm/Audiolab-8000-series-Service-Manuals-Parts-List-S-P-Q-M-CD-AV-X7-/170899484519?pt=Vintage_Electronics_R2&hash=item27ca672f67

Many thanks:cheers: :cheers:

 

[Mooly]

Circuit is showing on Hifiengine dot com. Reputable and free.

Does the 8000 use relays for speaker protection ? They can be a common cause of low/distorted audio at low volume due to contact deterioration.

 

[eggontoast]

can't help much but heres a link to a service manual up for sale http://www.ebay.com/itm/Audiolab-8000-series-Service-Manuals-Parts-List-S-P-Q-M-CD-AV-X7-/170899484519?pt=Vintage_Electronics_R2&hash=item27ca672f67

That link is for the later Audiolab models, complete circuit diagrams or service manuals for the 8000A are difficult to come by. The best you will probably find is a schematic for the power stage.

You haven't said which version you have but there were three distinctly different versions of the 8000a, the first had 5 pin din inputs, the second has silver phono inputs with a provision for cartridge loading on the phono input and the third black (although the early ones had a grey case and black front) version with the gold inputs which fall to pieces. None had relay protection and these amps can be a real pain to work on if you don't know what your doing, you could land up in worse trouble. If I were you I'd probably get it serviced properly, someone like Kevin at the Audio Cellar would be able to help you out. If you want to have a go yourself I would suggest you get yourself an ESR meter and check all of the caps, most can be done in circuit, others have to be removed. These amps do suffer from dried out caps as they run quite hot inside although, I'm not entirely sure that's what you problem is, it sounds like your getting a burst of oscillation on power down.

 

[toyota man]

Hi guys I missed your posts I am not sure which model it is but if its a pain to work on I will get it seviced many thanks for your advice:cheers: :cheers: