The Amp Garage

award70 wrote: ↑Fri Apr 12, 2024 5:28 pm This seems ridiculous but people that review "audiophile" fuses say they make a difference. What the heck is going on?

https://www.stereophile.com/content/hifi-tuning-fuses

Probably has nothing to do with the fact that these websites earn revenue from advertising for these companies.

What about Soldano? How the heaters are wired on an SLO flies in the face of everything posted here. So I think heater wires are not as critical as some make it out to be. Yup, I don't bother with twisting for the preamp anymore, just run short straight parallel wires from socket to socket. I do DC...

I was interested in the composition of Orange Dual Dark, so I looked at the related circuits. I can't find Dual Dark's official circuit, so I have to guess, but judging from the tube layout, I'm guessing that the Jim Root Terror and Dark Terror preamps are probably assigned to each channel and swit...

Transistor is used if you need to switch multiple relays from one switch. Also you can use LED indicator either in the amp or in the pedal without needing any additional circuit. Just connect a LED from CTRL to ground and when you short CTRL to ground the relay switches and led turns off. Hey, than...

I haven't twisted filament wiring in years, I can't hear any hum so I don't bother.

DC elevating them makes a much bigger difference (as in the hum disappears entirely). Maybe it's because they're elevated that non-twisted works well.

Thanks for the photo and info. Looks great! Yes, I wondered if the 47R resistor was worth the trouble, so it's interesting to hear that you decided to remove it. Thanks for the good info re the FET boost, too. I have a build coming up that will use one, so I may try your method with the higher valu...

Very cool build, Snicksound. I know you no longer have the amp, but do you have any guts photos you could share? Curious to see the final board and layout. Also, I have a couple of questions, if you don't mind: 1. The 47R resistor after the rectifier, how did you arrive at the value? 2. About the F...

This will probably be the last post on this amp as it's going to its new home tomorrow. See below the final schematic and a potato quality demo. I did get to play one gig with it and it was GREAT. I found the boost to be a bit intense for some songs so I complemented with my pedals. When I wanted pr...

So here's where I'm at. Very satisfied with the circuit like this. Will be posting some clips soon hopefully. While this ain't no Blackface clean, the clean and dirty channels are well balanced. One interesting tidbit though, I wasn't so sure when playing through my G12M-65 Creamback equipped cab, a...

this is an extremely interesting post, please keep us up to date.. :D Thanks! The amp is making sound now (still many things to hook up though), First lesson learned: the shared dual mode Presence control was not a good idea. In theory it should work but it created some kind of oscillations issues....

The master on this amp is awesome. Have no fear of the 50w power section. That's the plan! I want this amp to be easy to control for living room noodling, while having enough power on tap to do unmic'd gigs with a solid low end. Too many high gain amps are porting over their master volume straight ...

Very, very cool. You've addressed all the things I wanted...immediately after finishing my recent 2204! My honeymoon with the 2204 just keeps going on and on... Thanks Fun fact, after I'm done building this one and delivering it to my friend, my next project is rebuilding my personal 2204 clone... ...

Managed to fit everything on a 11.5" long board. (NB: the 10uF caps in the DC elevation and NFB bypass circuits are reversed in this image) https://1.bp.blogspot.com/-YAPpDAWhGw4/YB1kD0xeTAI/AAAAAAAANa4/09S99zcm8RcDmdzYycvmTbNSP9PZrRigQCNcBGAsYHQ/s2711/Dual%2BMarshifier%2BLayout%2BChassis%2B-%2BBoar...

Fixed an issue in the bias supply (cap polarity... easy mistake to be avoided!) Also realized that dual ganged 25kB pots are pretty much impossible to find, but then realized I can accomplish the dual mode Presence with a single gang. Simply ground the wiper, connect the "Marshall" side to the top l...

Colossal wrote: ↑Sun Jan 17, 2021 8:20 pm R15 and R16 reversed?

Oh, good catch! Thanks

Also added the power supply:
(Updated schem in next post)