can someone explain the Dumble "deep" switch circu

[pula58]

I see a schematic of it on Schematic heaven, but, can't understand how it works.

Could someone explain it to me, or, show me an alternative schematic....

Thanks!

P

[Structo]

It switches in a .01uF cap with two 270K pads through a 10K tail to ground.
It's between the volume and bass pot.
#124 had one pre 1988 when it was changed to the Skyline stack and mid boost.
I really didn't care for it, kind of muffled.
Apparently HAD didn't either because he changed it to a mid boost.

[Max]

kind of muffled.

Hi Tom,

As you of course will be aware this is just your personal perception based on your personal taste. Many Dumble players - SRV and David Lindley being only two examples - did use the deep switch to achieve sounds that at least IMO don’t sound "muffled".

Here are two video clips with demonstrations of the clean and overdrive sound of an original Dumble ODS with the deep switch in the upper "on" position:

http://www.youtube.com/watch?v=SNSAj6AzWGo (in the firts part of this video it's obvious for the most time if the the deep switch is in its upper "on" position or "off")

http://www.youtube.com/watch?v=-qvMwCte8TE (at 7:24 you can see that all these high gain OD sounds have been done with the deep switch in the upper "on" position)

I really didn't care for it,...
Apparently HAD didn't either

Here's what Alexander Dumble said concerning the deep switch:

"Instead of a single bright/deep switch, most of your amps have separate bright and deep switches. Can you use both at the same time?

Oh, you bet. It gets luscious low notes that you could float on and beautiful, crystalline highs that are silky as glass."

source: http://personalpages.manchester.ac.uk/s ... /Articles/

Concering the "classic" version of the circuit of #124 I would recommend to use this layout https://tubeamparchive.com/viewtopic.ph ... 262#140262 in order to check if the schematic posted in Tom's post is correct, especially the values in brackets.

Here are two more layouts of circuits with a deep switch:

https://tubeamparchive.com/viewtopic.ph ... 259#140259

https://tubeamparchive.com/viewtopic.ph ... 261#140261

Cheers and a great weekend,

Max

[Structo]

Hey, Max
All I can go by is my personal experience.
What do you base your opinions on?

[dobbhill]

I like the deep switch option on my non-HRM, but the response is definitely speaker dependent.
YMMV
D

[talbany]

The Deep Switch put simply is a passive RC circuit that dumps frequency's (set up by the cap value) to ground.. Much like a guitar's tone control..Accept where the guitars is variable and the DS is fixed (by the resistor)..BTW you can play with the value of both resistor and cap values to tweak the circuit if it sounds to dark for your setup,or just use the tone control on your guitar..
Hope this helps!!
Tony

[FUCHSAUDIO]

A agree with Tony. It's more a switch that lowers everything except bass, so it makes the sound deeper, more so than being a bass boost. It's subtle, although you can reduce the resistors as much as you like to increase the effect, should you want to. It does reduce overall gain, which some people don't like. Since we have mid and gain boosts on pull pots, we kept that feature. Some guys dig it, others not so much.

[pula58]

Perhaps one of you guys could post a schematic or simple drawing that shows the tone stack with the deep switch engaged vs.tone stack without the deep switch.

I have seen a few schematics that show the deep switch layout, but not a schematic that clearly shows the circuit as it is when the deep is engaged.

It looks like two 270k R's connected in series between the junction of the treble/bass pot and the output of the volume control pot. And then, with a network connected between the junction of the two 270K R's to ground. Is that right?? How could that boost, looks like it will result in less signal.

Please enlighten me, I need a push i nthe right direction.

Thanks!!

P.

[pula58]

Perhaps one of you guys could post a schematic or simple drawing that shows the tone stack with the deep switch engaged vs.tone stack without the deep switch.

I have seen a few schematics that show the deep switch layout, but not a schematic that clearly shows the circuit as it is when the deep is engaged.

It looks like two 270k R's connected in series between the junction of the treble/bass pot and the output of the volume control pot. And then, with a network connected between the junction of the two 270K R's to ground. Is that right?? How could that boost, looks like it will result in less signal.

Please enlighten me, I need a push in the right direction.

Thanks!!

P.

[Structo]

You just have to look at the schematic and visualize how the signal path is when the relay is closed.