Convert PCB amp to point-to-point?

Chalky

Anyone ever tried this? Is it straightforward or difficult? What are the pros and cons?

jpfamps

Depends on the amp, but it could be a total pain in the fundamental, and largely pointless.

I would definitely NOT recommend doing this in a high gain amp as you could end up with major stability issues.

I've done this sort of work on a few amps, but usually it's building a different amp, eg putting a 5F6 Bassman into a Deville chassis.

Can be a good project, but probably not worth paying someone else to do the work.

Gagaryn

Basically throw away the board and start again - layout is usually (always?) different. Pros - not sure if there are any, would be easier to fix because you made it and understand it I suppose. Cons - it's a lot of work!

Chalky

Thinking along project lines - there are some dirt cheap amps out there that I guess might form a start point for tweaking?

jpfamps

Chalky said:

Thinking along project lines - there are some dirt cheap amps out there that I guess might form a start point for tweaking?

If you were looking to build a 1 x 12 40W combo, then it would certainly be cheaper to buy a used Fender HRD, rip out the guts and wire your own amp in there than to buy the parts on their own.

Chalky

Very interesting @jpfamps as I have a surf green HRD that I was going to sell soon, now that my Redplate is settling in. What is it about the HRD that makes it a prime candidate for conversion?

jpfamps

Chalky said:

Very interesting @jpfamps as I have a surf green HRD that I was going to sell soon, now that my Redplate is settling in. What is it about the HRD that makes it a prime candidate for conversion?

They are cheap 2nd hand!

Not a bad space to fit another amp in.

Transformers fine.

Need a bit of metal work.

If you wanted to buy the parts it would cost a lot more than the value of the amp.

Chalky

Got it thanks. Hmmm, now..... what design to go with....

hywelg

A certain Mr Dumble did few similar conversions.

steviebee74

I did this a couple of years ago (sort of)!

I bought an amp from a guy on Ebay that was actually a Fender blues junior Chassis transplanted directly into a very good quality birch/tweed cabinet with a 1x10/1x12 speaker configuration. The speakers were also very good quality too!

The blues junior had the usual buzzing/rattling issues and I wanted a bit more power so I got a local amp guy to build me a new chassis and board arrangement to go straight into the existing cab/speakers.

He did me a 45w non-master volume, valve rectified, fender-style tone monster powered by 2x6L6, 3x12AX7 with valve powered reverb! He also assures me that only the very best components were used in the making.

Initially, I had it voiced as quite low gain for Jazz type stuff but then moved bands so took it right back to him and he completely re-voiced it in about two days for £30 or so. This is the beauty and advantage of point to point wiring: It can be repaired, modified and worked on very easily by someone who knows what they're doing. P2P wired amps also suffer less in transit as printed Circuit boards tend to be much more fragile and less shock absorbent! I've also had zero reliability issues in two years. Even the valves are more efficient due to the better design.

If anyone wants the contact for him, you're welcome to PM me for his details!

Cheers

ESchap

I did it with a Vox Pathfinder, converted it to a point to point AC4 using transformers from an early 1960's Philips reel to reel tape recorder.

Great little amp and the vox chassis was ideal for the job and the cab looks the part.  Link to a thread on it.

http://www.thefretboard.co.uk/discussion/1049/turning-a-reel-to-reel-tape-deck-into-an-ac4-first-amp-build#latest