S/P switching & selective tone controls?

[reTrEaD]

Hey kids, don't try this at home.

I was considering the possibility of using separate tone controls for the series mode and parallel mode of a S/P switch. Parallel was relatively easy. The function deletes itself in the series mode, if the correct connections are made to any S/P switch. This is because the needed connections "collapse" on each other in the series mode.

The series tone was more difficult to eliminate in the parallel mode. There isn't a "collapse" in the appropriate connection. So I went back to the drawing board, regarding the typical S/P switch architecture. A revamp of the structure allowed for using the pole on the right side, differently. Where this pole is normally connected to the (+) of the B coil, it could instead be connected to the output. The B coil (+) is connected to a throw (parallel mode) rather than the pole. This leaves the unused throw in the series mode open so an external element could be connected to the output in the series mode, only.

The upper right diagram is provided for an uncluttered view of the new switching structure. And there are 3 other circuits displayed more for "completeness". But the two circuits at the right of the top and bottom rows are rather fresh.



I've started this thread in GW, asking that it be vetted for correctness and usefulness. Barring any errors it might be worthy of a move to "Design Modules"?

I'm interested in knowing whether this is a lily too heavily gilded, or if some of it is likely to find a home in someone's designs.

[newey]

I'm interested in knowing whether this is a lily too heavily gilded

You do realize that this is guitarnutz2? Too much is never enough!

They look OK to me, although I'd certainly like a second opinion. If we get that, I'd say by all means, repost them in Design Modules.

One concern I did have (and maybe you can alleviate my concerns on this point, I may be wrong) is that, on the two "A Bypass" diagrams, (both the series and parallel tone variants), I would think that the tone pot, being "wrapped around" the A coil, would load that coil moreso than the B coil when in parallel mode. This could reduce the output of A relative to B, resulting in a bit of a mismatch in output even when the pot is at 100% (since it still represents some amount of added load).

However, a no-load pot would take care of that, if indeed it is a potential issue.

But again, let's get another voice, I'm often wrong on these things!

[newey]

Not exactly the same, but these ideas put me in mind of this:



From ChrisK's "Fun with Toggles and Push/Pull switches"

[reTrEaD]

I'm flattered by any comparison to ChrisK.

One concern I did have (and maybe you can alleviate my concerns on this point, I may be wrong) is that, on the two "A Bypass" diagrams, (both the series and parallel tone variants),I would think that the tone pot, being "wrapped around" the A coil, would load that coil moreso than the B coil when in parallel mode.

I have to wonder if you meant to say series mode, rather than parallel mode?

Anywho, here's a little more info on how things are meant to work:

The A - Bypass and B - Bypass function the same way. It's just a question of which coil is being bypassed in the series mode.

The "Series only" and "(and Parallel Tone)" define a functional difference. Series only is just that. The variable "cap bypass" is present in when series mode is selected. The cap and pot are out of the circuit when parallel mode is selected. The "and Parallel Tone" version acts like a variable "cap bypass" of one coil when series is selected, but acts like a regular tone control when parallel is selected. Since the leads of both coils are directly connected in parallel mode, whatever the cap and pot do to one coil, they do in equal measure to the other coil.

The imbalance you mention is present in the series mode. At lower resistance settings, it's just what we want. However it is still present (to a very small degree) even when the pot is at full resistance. It might be desirable to use a no-load pot so that it's fully out of the circuit.

[newey]

I have to wonder if you meant to say series mode,

I did, my mistake.

[4real]

Hey, more modules the better.

I've found the GN2 modules some of the best things in understanding how component circuits work and finding options...in fact a young man who had emailed me was also requiring and done a strat last week with a mid pickup blend kind of thing...as always said to look here and start a thread for the 'experts' to look at it and of course, the solution was found in the module section as to why his was working as a second master volume...had it fixed by the afternoon.

It is a reminder that people use the resources of the GN2 forum without ever posting and it is a great learning resource....more so when things are broken up like this.

...

Looks ok, but what would I know! Guilding the lilly, well the diagrams are clear and it is a nutz house so I guess people might like dualing tone controls, there is an application...I love Becks sound and some of his kinds of 'tones' use the tone controls a lot and such arrangements could be used to 'switch' to a pre-set 'sound' (I sometimes used to use this kind of thing when I played an LP...plus you can get a 'wha' type effect by kill switch kind of things with the S/P selector with extreme settings and tone controls).

I imagine one might set the amp to sound good with the darker series mode and then use a parallel tone in parallel to tame that down if over bright too.

I'd probably tend against more than one tone guitar these days though for myself though they can be useful, especially on a really bright guitar like a tele...but then you only have one knob!

However, seeing these, the same principles could perhaps be bent to altering a full phase to a HoOP switch in different modes. On my strat with S/P modes, the use of the phase can make for some cool sounds, especially in the darker series mode and while overall happy with it's hoop switch, it might be an even better effect if it were full phase in the series mode...just a thought, and another application I guess.

So sure, more the merrier and modules in particular can inspire such ideas and help others look at these things in separate modules.

I even try and wire in modules these days, outside the guitar on cardboard, and testing each system before it becomes a mess of spaghetti. Generally tone control wiring comes last after I am sure that say a S/P thing is functioning as it should. Again, discrete modules like this can really help.

That's a great old diagram of CKs there...shame so many of his diagrams are in those less clear 'schematic' kind of things...the price you pay I guess.