Blues Deluxe to ODS #183 Thread

[pompeiisneaks]

Phil
The pot on the ground of the mid pot is some kind of variable boost control. Dumble put this on some of his amps like the Ripper Charlie posted in the files section. Since the Bluesmaster AFAIR has the mega boost which lifts the stack out completely when in OD. Although I have never used this in my Bluesmaster it looks like it would be a pretty cool mod. You can always add it later or add a fixed value resistor (76K I believe)if the boost is too much for you.

The Bluesmaster stack is different from the Skyliner. It's set up more like a typical Fender Marshall tone stack so I would treat it as such.

The 312K Bass pot was the original value in 183. and was IMO the value Dumble wanted. He more than likely went through his Stash of 500's and kept the lower value ones for use as bass pots. This is my guess since these high plate Skyliners can be a little bass-heavy and 183 had both 250k values for both Drive and level controls. Remember 183 was a Skyliner so check the value of the bass pot on my layout as it is different on a Bluesmaster 50k.

250K A Treble pots and yes Dumble used the 22M on his PAB boards of his Bluesmasters. BTW you want to use CC resistors there if you have any to help smooth out the boost.
The rest of the guys can help you on the boards

Good Luck!
Tony

Cool, thanks Tony! I'll have to live with the 500k pot I guess. Although I guess I could put say a 310k across the input and ground to get closer to the 312k right? I could do the math on that I guess, but that would mean the max the pot sits at is around that 312k? No?

Thanks for the tips!

~Phil

[talbany]

Phil
The pot on the ground of the mid pot is some kind of variable boost control. Dumble put this on some of his amps like the Ripper Charlie posted in the files section. Since the Bluesmaster AFAIR has the mega boost which lifts the stack out completely when in OD. Although I have never used this in my Bluesmaster it looks like it would be a pretty cool mod. You can always add it later or add a fixed value resistor (76K I believe)if the boost is too much for you.

The Bluesmaster stack is different from the Skyliner. It's set up more like a typical Fender Marshall tone stack so I would treat it as such.

The 312K Bass pot was the original value in 183. and was IMO the value Dumble wanted. He more than likely went through his Stash of 500's and kept the lower value ones for use as bass pots. This is my guess since these high plate Skyliners can be a little bass-heavy and 183 had both 250k values for both Drive and level controls. Remember 183 was a Skyliner so check the value of the bass pot on my layout as it is different on a Bluesmaster 50k.

250K A Treble pots and yes Dumble used the 22M on his PAB boards of his Bluesmasters. BTW you want to use CC resistors there if you have any to help smooth out the boost.
The rest of the guys can help you on the boards

Good Luck!
Tony

Cool, thanks Tony! I'll have to live with the 500k pot I guess. Although I guess I could put say a 310k across the input and ground to get closer to the 312k right? I could do the math on that I guess, but that would mean the max the pot sits at is around that 312k? No?

Thanks for the tips!

~Phil

Phil

I was simply answering why I thought Dumble used that value pot on the Bass. It was IMO by no accident. Obviously not everyone has a pot laying around that is around 312K use whatever value pot you wish.If the amp ends up being too bass-heavy with a 500 at least you'll know why
That's correct top of the pot to the bottom should read 312K 2 resistors in parallel correct.
BTW.I thought you were going from a 183 to the Bluesmaster I missed the top of your last post you're going the other way around Gottcha now

Good Luck!!
Tony

[JazzGuitarGimp]

Okay so as I mentioned the original of this board uses a Bluesmaster for the design, but I'm pretty sure it can be adapted to a #183 but I do have a few questions. See the attached section of the tone stack.

Bluesmaster for the board:
BMTS.png

#183 for the same section:
183tonestack.png

The part that's got me a bit confused, is that it seems like there are a few things I'm not 100% sure about.

For the middle pot, there are two things:
1. the 250kb pot in the 183 goes directly to ground
2. the BM has a switchable trim pot that is also linked to a relay. I'm guessing I can omit this? Which seems to me that I just either ground the pot myself and ignore that section of the board, or I can wire the ground of the pot directly to the bottom of where that trim pot goes? Is there any potential for issues with that relay being left 'on' and doing nothign?

For the Bass, the BM goes into the top of the mid, but in the 183 it goes directly to a 10k to ground. I'm guessing I could cut the trace on the pcb or better yet, just not run the bass grounding lug to the board and just connect it to a 10k resistor and then to a local ground on the board?

Other than that, there are quite a few component changes.

Two that had me scratching my head were:

312kb bass pot, I'm guessing this is the measured value and it's one of those cases where he scratched at the carbon trace of a different pot to get it to that value. How much of a problem is it going to be if I just use say a 500k pot instead? or would 250 be better?

270ka treble pot, same as above? Just a 250k? or 500?

and the final question, the Rock/Jazz switch and PAB in the bluesmaster doesn't have the 22M resistors that the one in the 183 (and 124 I did) have, are those needed, and if so, where could I likely connect these (more for xtian and/or jazzguitargimp since they know the board).

Thanks!

~Phil

Hi Phil,

It looks like most of your questions have been answered. But I wanted to touch on the 22M resistor question. The BM, on which this board is based, does not have a 22M on the J/R switch. Aaron can probably tell us if this is problematic or not, as I haven't built one yet. He hasn't said anything to me, so I assume all is well. As for the PAB switch, the BM indeed has a 22M resistor, but have a look at the screen shot, and you will see it does nothing, so I opted to leave it out. The attached screen shot is of the BM schematic published on TAG. I don't know if this was a mistake in the transcription from the donor amp (I really doubt this), or if perhaps HAD was going for something and changed his mind, and just left the orphaned resistor in place. There may some discussion about this on TAG.

There were a few 'perks' that either Aaron suggested (i.e. the variable PAB trim pot) or I dreamt up (some of which was deemed impossibly convoluted and was removed in the Rev B design ) But if you ever have any questions about any of it, I am here to help. So please feel free to reach out to me any time.

Lou

R9.png

[xtian]

No issue here with the “missing” 22M resistors.

[pompeiisneaks]

Well video one is done, let me know if there's any glaring errors.

After this I did some more work, pulled the old board etc, and found the standoffs in the BD don't match the HRD

Oh well. I'll just redrill for them to fit.




Enjoy,

~Phil

[xtian]

and found the standoffs in the BD don't match the HRD

Oh, no! Thanks for the tip.

[pompeiisneaks]

and found the standoffs in the BD don't match the HRD

Oh, no! Thanks for the tip.

Yeah the board lines up just fine in the chassis though, so it's going to be just redrilling some holes and moving standoffs.

~Phil

[talbany]

Phil
HRM= Hot Rubber Monkey Not Kidding.

Tony

[JazzGuitarGimp]

Hi Phil, would a drawing with dimensions locating the 10 mounting holes help?

[JD0x0]

Phil
HRM= Hot Rubber Monkey Not Kidding.

Tony

I always thought it was Hot Rodded Marshall (Almost dead on Marshall values, except plate driven rather than CF)
I always thought the Rubber Monkey was just a joke and to avoid possibly rubbing Marshall's Lawyers the wrong way..

My newest build has a PRM stack. Progressive Rock/Metal

[pompeiisneaks]

Phil
HRM= Hot Rubber Monkey Not Kidding.

Tony

Good to know, I'll correct that in my next vid

~Phil

[pompeiisneaks]

Hi Phil, would a drawing with dimensions locating the 10 mounting holes help?

Yeah it might so I can use it as a template. Thanks!

~Phil

[JazzGuitarGimp]

Hi Phil,

Sorry for the delay. Here it is.

Cheers,
Lou

[pompeiisneaks]

Excellent, thanks!

~Phil

[fred.violleau]

Hey Phil,

Just watched your video, nice project!
As I built a HRM with a defeat switch, I must say I enjoy the non HRM sound more than the compressed HRM.
Since your PCB has a jumper to bypass the HRM tone stack it would be fairly easy to add the switch. I think it opens up the sound a lot and offers a lot of flexibility.

My 2cents

Fred.