Bryston 3B Pro restoration.

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I'm just starting a rebuild of an older Bryston 3B.
I got it for $30, apparently it had a bad channel. For the price I figured it was worth a shot, I could always use it for parts.

Before I tore it down I thought I would try it first, I did get sound out of both channels if I played with the power switch. So it looks like I might be in luck. :sing:

It's filthy and a little worn, it is well used. I would imagine it has been used everyday since it was new.

So I figure I will have at it, the problems might go away with a good cleaning.

I am going to re-cap the power supply, although I might use it for a bit with the old caps against my better judgement.

Anybody done any "upgrades" to their Bryston?
 
Yes it is dirty. It takes multiple steps to get it clean. Goo-gone and then TSP. Sometimes I have to repeat the process.

OK so I checked the capacitors for fun. They read a little low, but seem to be functional.
My capacitor checker is the low voltage type. (BK precision 820), so I don't have a whole lot of faith in the test.

Now the filter caps are 7500uf+7500uf 50v in series for each channel. This gives ~3500uf @100v.
I wonder the reasoning for this? Simply to raise the voltage rating of available caps?

I guess I could just replace the 7500uf + 7500uf 50v's with a single 3500mf cap at 100V? (If available)

Not that I needs it, but maybe I could increase the capacitance while I'm at it.
 
Sorry Lanchile, looks like I'm going the DIY route! You are right though.
I actually might see if I could get my own tour there one day, would make for an awesome road trip.

So I finally got the thing cleaned up. It sure was a lot of work. I have cleaned every part except the actual circuit boards. I will do them separately.

I fought in -20 weather inside of an improvised paint tent to get my polyeurea coating on. Barely got it done with out screwing it up. lol.

Here's a picture of the assembly started. I installed some new feet. If those Hammond transformers don't give you a hard-on there's something wrong with you.
 

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Sorry Lanchile, looks like I'm going the DIY route! You are right though.
I actually might see if I could get my own tour there one day, would make for an awesome road trip.

So I finally got the thing cleaned up. It sure was a lot of work. I have cleaned every part except the actual circuit boards. I will do them separately.

I fought in -20 weather inside of an improvised paint tent to get my polyeurea coating on. Barely got it done with out screwing it up. lol.

Here's a picture of the assembly started. I installed some new feet. If those Hammond transformers don't give you a hard-on there's something wrong with you.

Good for you GloBug. What kind of amp are you going to build with those transformers 70vac secondaries?

PS: I had a Bryston B60 before, but I sold it and went for a diy integrated amp. Happy as a clam!!!
 
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I had not made a choice yet for caps although they are the usual suspects.

It would be nice to get some the same diameter as the original for the power supply, as they would fit in the original clamps.

If not then I have many to choose from.

I will look into the Nippon Chemicon KMH while I'm at it.
 
I had not made a choice yet for caps although they are the usual suspects.

It would be nice to get some the same diameter as the original for the power supply, as they would fit in the original clamps.

If not then I have many to choose from.

I will look into the Nippon Chemicon KMH while I'm at it.

Bryston uses those caps in all the amps. make sure you get "ORIGINAL" caps, I have seen fake ones as everything else. you can try Panasonic FC or go crazy like me and get Mundorf Audio grade caps 125c for power supply, they are expensive but worth every penny.;)
 
The price is not too bad on those, I assumed they would be higher then most the caps on eBay. Not bad at all. I figured I would budget about $100 on P.S. filtering.

I am going to have to play around with the values. They do have 10,000uf @63v, I could use two of those in series for 5,000uf @126v.

I don't want to go to high over the original value, which I take to be 3750uf @100v per power supply. I should have a look at the schematics to make sure that is the correct value.
 
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