Working on a Dumbleator

[Vertigo]

I was wondering if I could get a little help...I'm still working on my schematic reading fluency and this one from Claus has me a little confused. My hope is to add the MESA parallel circuit to Martin's adapted circuit.

I can see on Martin's schematic that the SEND jack is a TS and RETURN is a TRS

In the Claus-ulator III schematic, the "original layout appears to use TRS in both the SEND and RETURN

In the adjusted MESA schematic, it appears that the ring on the RETURN jack is no longer connected. Also, there's what appears to be drawn as a resistor, that I think is actually the return pot.

Am I on the right track here? It looks like I can add a wire between the send pot and the new 25K pot, need to reroute the wire from the send jack to the middle lug of the new pot and that the RETURN jack can be changed to a TS jack since the ring is no longer in use.

Claus-ulator III.bmp

[martin manning]

The loop jacks have no ring connection, that is only seen on stereo (TRS) jacks. Loop jacks are TS only, with or without a shunt, which is a switch that opens when a plug is inserted. One pole is the tip contact, and the other is the third solder lug. To add the serial-parallel control pot, just connect it as shown in the diagram. The shunt (if present) is simply not used on the return jack.

[talbany]

I was wondering if I could get a little help...I'm still working on my schematic reading fluency and this one from Claus has me a little confused. My hope is to add the MESA parallel circuit to Martin's adapted circuit.

Claus-ulator III.bmp

I helped design this Claus III schematic..I've also built several of these with the "Mesa" Blend control. Iv'e had issues with this design having some fairly large Null points leading to a real touchy sweep.Later we upgraded this with a dual ganged pot wired Reverse (Opposite lugs grounded) that provides a more smoother/even mix control across the entire range of the pot eventually grounding out 1 of the 2 signals so you may want to check that one out as well. I've built several of these that work great and much easier to adjust on the fly..You can use either a 250 or 500k there..let me know if you have any questions?
Nice Project!!
Found it,

Serparallel.jpg

Tony

[Vertigo]

The loop jacks have no ring connection, that is only seen on stereo (TRS) jacks. Loop jacks are TS only, with or without a shunt, which is a switch that opens when a plug is inserted. One pole is the tip contact, and the other is the third solder lug. To add the serial-parallel control pot, just connect it as shown in the diagram. The shunt (if present) is simply not used on the return jack.

Thanks for clarifying that for me.

[Vertigo]

I was wondering if I could get a little help...I'm still working on my schematic reading fluency and this one from Claus has me a little confused. My hope is to add the MESA parallel circuit to Martin's adapted circuit.

I can see on Martin's schematic that the SEND jack is a TS and RETURN is a TRS

In the Claus-ulator III schematic, the "original layout appears to use TRS in both the SEND and RETURN

In the adjusted MESA schematic, it appears that the ring on the RETURN jack is no longer connected. Also, there's what appears to be drawn as a resistor, that I think is actually the return pot.

Am I on the right track here? It looks like I can add a wire between the send pot and the new 25K pot, need to reroute the wire from the send jack to the middle lug of the new pot and that the RETURN jack can be changed to a TS jack since the ring is no longer in use.

Claus-ulator III.bmp

I helped design this Claus III schematic..I've also built several of these with the "Mesa" Blend control. Iv'e had issues with this design having some fairly large Null points leading to a real touchy sweep.Later we upgraded this with a dual ganged pot wired Reverse (Opposite lugs grounded) that provides a more smoother/even mix control across the entire range of the pot eventually grounding out 1 of the 2 signals so you may want to check that one out as well. I've built several of these that work great and much easier to adjust on the fly..
Nice Project!!
Found it, Serparallel.jpg
Tony

Thanks for the info, Tony. I'll stare at this one for a while and will see if I can figure out how to merge it with Martin's.

This is a great time for me to reiterate how much I appreciate the spirit of this place. Thanks to everyone here for patiently giving guidance and sharing so much information over the years. It reminds me a lot of my line of work and how open professional frame builders have been with sharing their tooling designs, techniques and thoughts about fit and bike design. It's a good reminder that I need to continue to give back for the benefit of those who are still coming up even though I'm a bit jaded

[talbany]

I was wondering if I could get a little help...I'm still working on my schematic reading fluency and this one from Claus has me a little confused. My hope is to add the MESA parallel circuit to Martin's adapted circuit.

I can see on Martin's schematic that the SEND jack is a TS and RETURN is a TRS

In the Claus-ulator III schematic, the "original layout appears to use TRS in both the SEND and RETURN

In the adjusted MESA schematic, it appears that the ring on the RETURN jack is no longer connected. Also, there's what appears to be drawn as a resistor, that I think is actually the return pot.

Am I on the right track here? It looks like I can add a wire between the send pot and the new 25K pot, need to reroute the wire from the send jack to the middle lug of the new pot and that the RETURN jack can be changed to a TS jack since the ring is no longer in use.

Claus-ulator III.bmp

I helped design this Claus III schematic..I've also built several of these with the "Mesa" Blend control. Iv'e had issues with this design having some fairly large Null points leading to a real touchy sweep.Later we upgraded this with a dual ganged pot wired Reverse (Opposite lugs grounded) that provides a more smoother/even mix control across the entire range of the pot eventually grounding out 1 of the 2 signals so you may want to check that one out as well. I've built several of these that work great and much easier to adjust on the fly..
Nice Project!!
Found it, Serparallel.jpg
Tony

Thanks for the info, Tony. I'll stare at this one for a while and will see if I can figure out how to merge it with Martin's.

This is a great time for me to reiterate how much I appreciate the spirit of this place. Thanks to everyone here for patiently giving guidance and sharing so much information over the years. It reminds me a lot of my line of work and how open professional frame builders have been with sharing their tooling designs, techniques and thoughts about fit and bike design. It's a good reminder that I need to continue to give back for the benefit of those who are still coming up even though I'm a bit jaded

Sure! This is an easy add on to any Dumbleator I've actually put them inside an amp. Let me know if you have any questions!.. Again Good Luck!
Also thanks for sharing your layout when you get it finished. It's always wonderful to see people posting any added info they used during their builds. Having read through just about every post from the Garage since it's inception the amount of info retained and shared here is mind numbing. Anything and everything you ever want to know and more about Dumbles amplifiers are somewhere deep within the Dumble Disussion/Files section of the Amp Garage.
I really need to get a life

Tony

[Vertigo]

Sure! This is an easy add on to any Dumbleator I've actually put them inside an amp. Let me know if you have any questions!.. Again Good Luck!
Also thanks for sharing your layout when you get it finished. It's always wonderful to see people posting any added info they used during their builds. Having read through just about every post from the Garage since it's inception the amount of info retained and shared here is mind numbing. Anything and everything you ever want to know and more about Dumbles amplifiers are somewhere deep within the Dumble Disussion/Files section of the Amp Garage.
I really need to get a life

Tony

This is slowly starting to sink in.

So, the dual gang pot...is that an audio or linear taper?

There is a 10K resistor in series between the return jack tip and center of one of the 500K pots? Did you put it on the board and connect off either side or do you have it hanging on to the end of the coax?

[Vertigo]

I'm a bit cross-eyed now. Please no-one use this until it's vetted. I've been flipping back and forth between two schematics and the layout so it's very likely that I've made mistakes, moreso that I've misunderstood the schematic. Once all the corrections are made, I'll clean it up and will post all the pertinent files.

Dumbleator Radial R0.1 (Ser-Par).pdf

[martin manning]

Back story on the dual-gang pot vision is it came from Engl. Claus' (aka bluesfendermanblues) drawing from 2013 is below. The #102 build thread referenced on the diagram is here (just in case you're looking for another rabbit hole): https://ampgarage.com/forum/viewtopic.p ... 67#p240867

Since the 10k's have no connection to any board-mounted component, I would put them on the pots, solder the end of the coax to the one that connects to the return jack, and reinforce it mechanically with a bit of heat-shrink. I think a linear taper would be best, as it's a blend and not a volume. Note that the way it's drawn, the blend control replaces the return input level pot on the original 3-knob Dumbleator.

edited: only one of the 10k's is unsupported a one end.

[erwin_ve]

Martin: Shouldnt the send fx side also have a 10k divider?

[norburybrook]

Martin: Shouldnt the send fx side also have a 10k divider?

it has Erwin, there's a 10k on the wiper of each of the two ganged pots.

M

[talbany]

So, the dual gang pot...is that an audio or linear taper?

I used a Linear taper 250K in both of mine. It's what I had (tbx) and worked fine I generally set my reverb/Delay unit to full wet and mix that in with a mostly dry signal..My pot sits at or around 9:00 (or 3:00 depending on how you wire your pots)
The 10k series resistors prevent the signal sources from being directly shorted to ground at any setting. And doesnt add to or detract from the sound.

Back story on the dual-gang pot vision is it came from Engl.

BTW..
Just to be clear and there is no confusion..I never said I came up with the "Dual-gang" pot idea. I said "I helped design this Claus III schematic".(AFAIR to place the EFX unit in phase with the Dumbleator). so everyone knew I was familiar with this design

Here is the thread you want with the Engl mod explained
https://tubeamparchive.com/viewtopic.ph ... light=engl
Tony

[Vertigo]

If someone wanted to package two loops in a 1U rack space, would you be able to modify the power supply to feed two signal boards and double up on the jacks and controls?

Would this PS work?

B8D53233-0F31-4E09-8743-1BD028651061_1_105_c.jpeg

[talbany]

Vertigo post_id=416852 time=1600226472 user_id=17070]
If someone wanted to package two loops in a 1U rack space, would you be able to modify the power supply to feed two signal boards and double up on the jacks and controls?

Would this PS work?

B8D53233-0F31-4E09-8743-1BD028651061_1_105_c.jpeg

Stereo Dumblator
https://tubeamparchive.com/viewtopic.php?f=5&t=5961

[Vertigo]

I was bent on getting this together yesterday but quickly realized that the transformer doesn't fit into the chassis I bought.

So PSA...if you want to use the Hammond 262A12 transformer in Martin's schematic, do not buy a Bud Industries CH14401 1U rack mount chassis. The internal height of the Bud is a hair over 1.5" and the 262A12 is going to be a tight squeeze into a 1.625" space. I just ordered a Hammond chassis, and supposedly the internal height is exactly 1.625"