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BGW amplifier - Replacing 1/4" inputs with RCA

Since there are some here that like BGW here is an image of my setup. Where I live they are not for sale all that often. The GTB was installed at the planetarium in Portland, Oregon up until 2 or 3 years ago, I left the labels above the input gain knobs, one was labelled LF and the other HF so a mono setup. All I know about the 7500 Pro Line II is that the Seller I bought it from mentioned it was previously owned by a friend, who used it in his garage for a few years. So far both are still working as well as can be expected though perhaps at some point a refresh of capacitors etc. might be worthwhile. There is a Seller on Ebay that offers kits, usually around 170.00 I believe but that includes the two main power supply capacitors though nothing for these two models specifically.



I was a bit late discovering the GTB, that Seller had three of them at 350.00 each but had already sold two unfortunately. Well known here for reel to reel repairs ( Curt Palme ). Had some very interesting stories to tell from when he did sound system installations which is how he ended up with the Portland planetarium amps.

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that makes sense then. 120v plugs just don't have any need for 4 pins. Not real hard to do dual voltage though, two primaries run series or parallel depending on supply voltage. Makes it work almost anywhere in the world. Tap them so it can run 100 volt mains and I think that covers everywhere.
 
You might want to note polarity as these earlier BGW's do not observe standard XLR pinout.
Excellent point. In the 80s and into the 90s the hot pin was a hot topic.
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Take a look at a Yamaha pro amp of the era to see how they did it
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Man I wish someone told me sooner that pro amps suck. Now I’m stuck with a bunch of paperweights :D

Btw, the GTB looks like a pretty nice amp. I have a BGW 250, 600, and 750.

And I still hate 1/4” jacks
Poor guy. I can take them off your hands if that will ease your burden.
 
They’re just so heavy. I should probably just take them to the scrap yard and then buy one of those Chinese clone amps that everyone seems to like nowadays ;)
 
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