Dirty Shirley Build

[craigkimble]

Greeting TAG,

First off, I appreciate the amount of information on this site. I came here a while back to build a Dumble clone and have been sucked into the rabbit hole. FWIW my #124 build came out amazing, still tweaking a few things, but its a really good amp . I've been building amps as a hobby for years, and have a nice collection going. It's time for a new one.

I own a 40W Dirty Shirley, and my band mates are in love with the amp. One of them has challenged me to build a version for him.

I have opened it up and so far have documented the layout and schematic. I plan on removing the FX loop at this time just to keep it a bit simpler since it's easy enough to add once the base amp is working. The other change I'm thinking of doing is using a set of Deluxe reverb transformers I currently have on the shelf and running it with 6V6 vs. 5881 output tubes.

Online resources for this amp that I've found are kind of incomplete so I thought I would share the work I've done so far in case it helps others. The layout isn't totally complete and is a bit of a mess, but you get the idea.

I believe these are pretty accurate, but let me know if you see anything that doesn't look right. The one thing that looks odd to me is the resistor network on the cap can at B+2. I would be curious to hear y'alls thoughts on that.

I made a quick video of my first look inside and posted it on youtube:

DS-layout2.0.pdf

Dirty Shirley Schematic 1.3.jsch.pdf

[pompeiisneaks]

Great job documenting that!

I've not seen that type of setup before either, but maybe the goal is to allow some power filtering WITH some sag, almost like a second cap behind a resistor to let it provide some filtering but through a slow discharge resistor?

I'd love to hear more about how that works too.

~Phil

[chief mushroom cloud]

HTR CT goes to that 470k/82k divider (raise heater DC ref level)
plate cap on PI should be 47pF
missing 1M across master

[craigkimble]

HTR CT goes to that 470k/82k divider (raise heater DC ref level)
plate cap on PI should be 47pF
missing 1M across master

good catch.. I saw the elevated heater CT but didn't even think that the divider was for that. I assumed it was a convenient place to put it. lol

I have fixed the other issues in the drawings and uploaded the new versions

Thank you!

[Reeltarded]

B+2 balance resistor? I can't see pdfs this device.. compare to 100w+ Marshalls with 56k balance resistors. Is that it?

Nice builds on these amps. I sort of hate the effects loops. I don't really love tube buffers either.. so..

Look. It's alunimominumiuim.

If you look at an early JTM45 you see 96% of what this amp is.

[pdf64]

Well done, I’m finishing off tweaking a 2204 / DS / JTM50 inspired build.
Are the coupling caps between LTP and output valve grids really 0.0047uF (4n7F)?
I definitely needed a bright cap on the preamp gain, and a treble boosting cap between 2nd and 3rd stages.
I’m surprised they’re still using unwelded / unbraced chassis corners.
What is the red to red resistance of the PT HT winding?

[Reeltarded]

That would be harsh

oops all the couplers PI and out are 100nF

(.1u like a JTM)

[craigkimble]

That would be harsh

oops all the couplers PI and out are 100nF

(.1u like a JTM)

He is correct.. I mislabeled the schematic. It is correct in the layout at .1u. I updated the schematic with the correct values.

[burger]

Build him a 2 x gains and 2 x masters version with my Double Shirley PC board.

[danman]

I purchased one of Burger's boards last year for a JJ jr build. The board and documentation were top notch and having two foot switchable channels with separate MV's is a nice upgrade. His board also offers a cathode bias/fixed bias circuit option should you decide to build it that way.

[craigkimble]

Build him a 2 x gains and 2 x masters version with my Double Shirley PC board.

Well, I already built the turret board but just purchased the FX loop board and got the drawings. Great implementation on the Double Shirley. May need to add that down the road.

Thanks!

[m.alexander]

great job, Nice schematics , but the layout don't open
please send new

[ChopSauce]

Yes it does open. You might want to check your browser config. or right click/save as and then open it?

[m.alexander]

Yes it does open. You might want to check your browser config. or right click/save as and then open it?

thanks buddy ... open now.

great work7

[Steveo]

The iec sockets in diylc always mess me up. On your layout are your wires to the iec socket showing the connections of the rear of the socket (inside the amp chassis)?