ampeg 4 pro trouble

[Bucket Head]

alllriteee, i just bought a second hand ampeg 4pro and bought it to practise today and cranked it all the way up and the eq seems to be fing up. basically it seems to cut the volume in half but when u move the end slider to the left (the one that turns up the power of the eq/ volume) it fixes it but then 10 secs later it will do the same. so i put a elastic band around it and put it to the other side of the eq to hold it to left and it has solved the problem for now. was just wondering if anyone else has had this problem and if anyone has any idea what thats gonna cost to fix?


again im very thankful to u guys for the advice, im always asking and never giving

cheers

[kaygee]

It could be a bad contact or some dirt in the fader, especially if the previous owner left the fader in one position.

With the amp off move the fader from top to bottom around 10 times, if that does not solve it, clean the fader with some electrical contact cleaner

[icastle]

[quote name='Bucket Head' post='1037174' date='Nov 25 2010, 11:58 PM']alllriteee, i just bought a second hand ampeg 4pro and bought it to practise today and cranked it all the way up and the eq seems to be fing up. basically it seems to cut the volume in half but when u move the end slider to the left (the one that turns up the power of the eq/ volume) it fixes it but then 10 secs later it will do the same. so i put a elastic band around it and put it to the other side of the eq to hold it to left and it has solved the problem for now. was just wondering if anyone else has had this problem and if anyone has any idea what thats gonna cost to fix?


again im very thankful to u guys for the advice, im always asking and never giving

cheers[/quote]

Well, it's one of three things:

1) Crud in the fader - get a can of switch cleaner, squirt a dose into the slot where the fader runs and slide the fader back and forth for a few mins.
2) Dry joint - the fader will be soldered to a circuit board and one of the joints has failed - easy to fix provided you have a soldering iron and appropriate skills.
3) Failed fader - the fader has worn out and needs replacing - awkward to DIY fix, but again, doable provided you have a soldering iron and appropriate skills.

Number 1) needs to be your first thing to do.
Numbers 2) and 3) will need tech help if you don't have (or are unsure) the appropriate soldering skills.

Cost wise - I'd guess a half hours labour for number 2) and an hour for number 3) plus the cost of a slider.