The Amp Garage

IMHO the cathode biasing and a feedback free power stage are keys for magical tone. no feedback amp=excessive highs, i dont know a person who wants this Lots of factors could cause this, but no NFB shouldn't be the sole cause of this issue. A cathode biased no NFB pair or quad of 6V6's can be a ser...

You can use a MOSFET B+ Dropper or other means to crop your B+ down if needed. I have use this to use 6V6s with a PT designed for 6L6s. Another thing that can be done is to use JJ 6V6S for your power tubes. They can be run at a higher B+ than other 6V6s in current production. I have used them at 46...

I'm not quite sure what you're asking. :) To my ears, 6V6s sound like mini-6L6s. I quite like them, and use them in all my more recent 20-ish watt builds (and once even in a 4x 30-ish watt design). They are typically run at voltages in excess of what the old data sheets recommend. They are similar ...

I'm not really sure. It can certainly take deep pockets. I own ODS(c) in the USA, owned it for years. In the US, a simple letter to another manufacturer (US based) usually gets things resolved. Most of the time, people don't search uspto.gov before they plaster a name on something. Moss used ODS on ...

Latest update; So the US battle appears over, since the UK guys stopped paying their US attorney and the process was halted and appears over for now. Meanwhile, in the UK, they hold a Dumble mark and plan to make amps and pedals using said mark. Time will tell how the US side responds and what actio...

and said "your amp is very similar to this one" and marked up the schematic with a highlighter to show suggested resistors to change...I found that hilarious.... :lol: Second easiest modern amp I ever worked on and I should otherwise keep my opinion to myself! It wasn't tough to work on, but it's t...

I just serviced a Carr with a noise complaint. They recommended changing some resistors to metal film, from the carbon film they shipped it with. the funniest part is they sent the customer an actual Fender Deluxe reverb schematic , and said "your amp is very similar to this one" and marked up the s...

The wiring difference is just that in one amp the two plates of ONE rectifier tube are in parallel. On the other drawing one plate from each tube is in parallel with the other tube.
Technically the "same circuit" just split differently between the two tube plates.

You are basically making the rectifier more efficient and handle more current. A single (larger) bottle would do the same thing basically.
I suppose you could pull one for more sag, but I would worry about drawing too much through the one tube might be asking too much.

@martin Manning, agreed. Randall tried to avoid direct Fender rips by using CCS diodes on preamps and in some power amps (like this one). Actually, an LED will do the job of a CCS nicely, but when Mike Bendinelli at Mesa tells you "we rip those dopey things out all the time", that tells you somethin...

It also appears they may have a heater CT on that same terminal strip (?). Either method (balancing resistors or ct) is usually fine, but both at the same time makes no sense. If you do the math, the values are not critical, nor is there much current through them either. In production, I use both me...

Pretty sure someone said Heyboer made something like this....

I like the IRF style devices as a loop follower. On the return side the LND-150 is great. Unfortunately, most suppliers are talking late 2023 for stock again. They are available in an SMD style, and making an adaptor to put them on a through hole board isn't tough. It's a cool device and I hope it c...

I got nothing....wow.

Workmanship and components look like it could be a Krinard. Was just inside a ‘73 Deluxe Reverb that he worked over. Something that never should’ve been released into the wild. At least those appear to be soldered connections. FWIW: I would be surprised if it was a Krinard build, it's a bit too nea...