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Db751 issue

A friend of mine have an issue with a db751 on the board just on top of the mosfet on the transformer side.
We are looking for pictures of each side of the board and the wiring schematic of the head.

Any help is welcome
 
A friend of mine have an issue with a db751 on the board just on top of the mosfet on the transformer side.
We are looking for pictures of each side of the board and the wiring schematic of the head.

Any help is welcome


I know from experience that Aguilar is pretty tight with releasing technical information. I was able to talk them into releasing schematics for my amp. I am an experienced technician and I had to sign a nondisclosure agreement.
 
Why don't you describe the issue you're having ? There are a lot of good tech people right here who might be able to steer you in the right direction.
 
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The aguilar warranty is limited to the first owner my friend is the 3rd.

We found the shop and the date of the purchase but the boss reject to give us the first owner details.

The head is 6 years old

I think the point is Aguilar is the source for the schematics. But as I mentioned, they are not real free with them and if they do agree to provide them to you, they will probably require you to sign an NDA. Because of their NDA policy, you are likely to find it hard to source the desired documents third party.

I can offer no further assistance so I will step out now.

Good luck.
 
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My 750 had a crackle on certain, lotsa, notes, when sitting on a cab or bumped etc
Was dry solder joint/s... pretty cheap fix, with a once over from the tech too!

Crackle sounds like tube circuit.

The one I fixed had loose ribbon cables and un seated tubes.

Kid had a taste of his first van/trailer tour.
Trailers vibrate and bounce too much for any amp.

pretty quick fix indeed
 
Am I reading correctly that Aguilar has no authorized service centers other than them selves and will only service under the warranty period? (10 years for DB751, 3 years for others) You must be the original owner, have the receipt. Maybe I'm reading it wrong, I sent an email to clarify and will update if I receive a reply.

EDIT: Received a reply from Aguilar and they will service outside of the warranty period. It's currently a $95 bench fee, plus shipping and parts. They will also work with local **qualified** shops. (My emphasis) and provide schematics as necessary.
 
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I can't really add anything as I have no experience with the DB751, but I did have a very good experience with Aguilar tech support back in 2008. It's a different company now, but schematics and technical details were pretty free flowing back then.
 
Am I reading correctly that Aguilar has no authorized service centers other than them selves and will only service under the warranty period? (10 years for DB751, 3 years for others) You must be the original owner, have the receipt. Maybe I'm reading it wrong, I sent an email to clarify and will update if I receive a reply.

I have also read they will not accept an amp unless it is in the original box.
 
I misunderstand why they are so restrictive. Having designed good products, which sell well, should not make them forget that even if you are the third owner, you remain a customer who keeps the brand alive
 
I misunderstand why they are so restrictive. Having designed good products, which sell well, should not make them forget that even if you are the third owner, you remain a customer who keeps the brand alive

On face value the strategy is meant to protect their intellectual property. There is also some aspect of risk aversion. Giving a schematic to someone who then goes and gets electrocuted working on the amp could potentially expose them to litigation.

The aspect where they don't support current production amps seems a bit odd though. But maybe this is overstated. Even if they don't have authorized service center or provide in-house service for older amps, they do make the schematics available to actual shops that repair amps. They just require an NDA.

In order to attain the schematics for my amp I told them my credentials. I am not a commercial technician but I own and maintain a fairly large personal collection of tube amps and have formal training and experience as an electronics technician. They emailed me the NDA; I signed, scanned, and returned it; and they immediately sent the schematics. On top of that, they were open to discussing the problems I was having and were a good source of parts for the amp. I really have nothing negative to say. I feel Aguilar was responsive and took care of me.
 
Here you have the pictures
 

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I have a problem with my DB751.After the 45 sec.blinking diagnostic light stops blinking and I push operate,nothing happens for about 5 minutes,then it worked properly,and continued to until another period of non use.Now the same thing is happening.Its in the shop now.Any ideas?relay?The pre and power seem to be coming on,just no sound.
 
I have a problem with my DB751.After the 45 sec.blinking diagnostic light stops blinking and I push operate,nothing happens for about 5 minutes,then it worked properly,and continued to until another period of non use.Now the same thing is happening.Its in the shop now.Any ideas?relay?The pre and power seem to be coming on,just no sound.


The only thing I can tell you is sending the amp for repair is the right choice.