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ACG Preamp (Big Problem, need expert)

Weshunter413

Weshunter413

May 6, 2009
777
30
Hickory NC
#1
Hi Talkbass I don't have anywhere else to go now. I bought a ACG-01 about 6 months ago from BBG and installed it a few days later but I turned the preamp around and installed wire numbers 1-5 backwards. When I plugged the battery in it literally blew up. The capacitors exploded. I contacted BBG and they told me I should contact Allan at ACG. Allan told me to ship it overseas to John East since he's the one who actully builds them. So I did. 6 months later I get it back. It never made it to John. I tried contacting him twice with no response. So I guess I'm stuck.

6 months later and I still haven't heard this preamp. Two of the capacitors exploded so I ordered two more and installed them and I still don't have sound. The battery is very hot after just a minute I can't even hold it.

Any Ideas? Thanks a lot for your input talkbass.

Wes

P.S. here's a picture of the motherboard right after it exploded.

44163A61-2852-4327-B7A1-F74844752139-2007-000003FABC02B840.jpg
 
#2
Strange mr. East didn't respond your mails, he was very helpful with my J retro issue, but may be busy so try again.

as of the circuit board, fortunately, there isn't much to blow apart from ICs.

they are relatively cheap and shouldn't be hard to replace by someone experienced.
 
#4
Those caps are polarized. Did you put the new ones in the right way? How did you know what value replacements to get?

You may have damaged the IC or some other parts. If the battery is getting hot, that means there is a short somewhere.

Hooking batteries up the wrong way is usually a very bad thing to do unless the preamp has protective diodes built in.
 
#5
Thanks for the replies. I just replaced the caps with the same value as the old ones 100uf 16v I had to order them. I didn't realize they were polarized. I'm not that great with electronic. I know just enough to get in trouble (as you can see). I didn't call him yet because I didn't want to pay the phone bill on top of everything else. I might not have the right email aswell. Does anyone know the best email to reach him?





SGD Lutherie said:
Those caps are polarized. Did you put the new ones in the right way? How did you know what value replacements to get?

You may have damaged the IC or some other parts. If the battery is getting hot, that means there is a short somewhere.

Hooking batteries up the wrong way is usually a very bad thing to do unless the preamp has protective diodes built in.
Click to expand...
 
#8
John is the man. He's always gotten back to me via email (from his website) within a matter of hours. I'm about to put one of these into my Modulus TBX. Great preamp. I'd say it'd be best to send it back to him directly. He's pretty quick about these things and very thorough, so he could fix the broken parts and double check the functionality of the whole preamp. He rebuilt my 1st generation J-Retro with all the upgrades and mods and turned it around in about a week.
 
#10
This is the first time I've shipped overseas and it has put a bad taste in my mouth. What's the best way to ship it to him? Last time shipping cost $30 and it sat in customs for around 5 months just to return to me (it does look like a bomb). I was hoping there was an easier fix that I could repair myself but it looks like it too much for me.
 
#12
Hi
Here is John's e-mail address.
[email protected]

Failing that you can PM on Talkbass he is a member of the forum.

The delivery address is.

John East
East UK
Bumble Clumps
Northampton Road
WESTON ON THE GREEN
OX25 3TJ U.K.


USPS Priority mail has always worked very well for me on items sent from the USA. I have had no problems with things sitting in customs for that length of time stuff usually gets sent right back if there is a problem.

It is important to put on the package the following.
Value for UK Customs is Zero.
Returning to country of origin for repair.
Without this there will be a custom charge on the unit when it comes into the UK

I think I sent you the address via PM when you first sent me the details.
We are both keen to see the pre-amp since this has not happened before and we would like to find out what caused this to happen.
 
#13
Thought I should point out that the underline on the e-mail hyperlink hides the underscores. So the part before the @ symbol should be:

john_east_uk

I have to say, this is incredible customer service. You bought a pre-amp, hooked it up wrong and blew it up, then tried a repair yourself and they are STILL interested in getting it back for repair. Interested enough to spoon feed you the contact details and method. The only thing they could do more is send a courier to your door and get the package.
 
#14
Hawkbone said:
Thought I should point out that the underline on the e-mail hyperlink hides the underscores. So the part before the @ symbol should be:

john_east_uk

I have to say, this is incredible customer service. You bought a pre-amp, hooked it up wrong and blew it up, then tried a repair yourself and they are STILL interested in getting it back for repair. Interested enough to spoon feed you the contact details and method. The only thing they could do more is send a courier to your door and get the package.
Click to expand...


I know and I'm still waiting on the truck!

All kidding aside I agree Alan has been great about this. I never blamed him or his product in any way. It is ALL my fault. I am also prepared to pay for my mistake as well. I would never expect them to cover cost on this. I just have a problem getting it to them.

Alan. I did as you said last time and shipped it out just as you told me to. I will ship it again. Doesn't it mean if there's zero value to the package I can't insure it? I shipped it out last time without value or insurance but I was sweating the whole time.

Thanks, again
 
#16
Alan sent the pic at the top of the thread as soon as he'd received it, sometime in the autumn I believe, and I must say I was shocked to see such devastation!

I immediately suggested Alan get the unit sent to me to fix it up.

I tried a unit here reversing a standard 9V battery, but the battery just got warm, nothing blew itself apart, although I didn't keep it that way for long.

The chips will take up to 36V, and 9V reversed will be soaked up by them for a while, but if the capacitors have popped, I would expect the chips to have expired too, since they will keep the voltage to virtually zero initially.

I would expect the power source to have quite some capacity in order to cause a near fire! (Taking account of the black on the surrounding components)

Was the power connected for a long period?

As Alan says:

VERY IMPORTANT, IN ORDER TO SAVE UNNECESSARY EXPENSE >>>

As and when you send it, please mark it boldly on the package, even if you include an insurance value elsewhere:

RETURNING TO COUNTRY OF ORIGIN FOR REPAIR

VALUE FOR UK CUSTOMS: 0.00 < the important bit!

Make sure it is on the shipping label(s) and written large on the same face. On any other face, UK customs likely to miss it!

(Otherwise we have to pay import duty and sales tax, amounting to around 25% of any value given to UK customs, which I will need to pass back to you)

Also, please email or PM to let us know to expect the unit - important.
 
#17
Hi John, thanks for chiming in. As soon as I plugged it in it exploded. The cap hit me in the head and I had a mark for a week on my forehead. I'm still laughing about it. I watch a video on YouTube with a guy blowing up caps and it pretty much looked like that. I am going to ship it to you again with the label just as you asked. Hopefully it makes it to you this time.

Thanks again for your help and I hope I didn't completely mess it up.
 

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