Author Topic: Shifting the position of a loop-select  (Read 535 times)

Mark Hammer

Shifting the position of a loop-select
« on: July 24, 2022, 03:32:49 PM »
I'm putting together a box with three different clipping circuits: a TS-808, Big Muff, and FY-2; each with several toggle-enabled options to change their performance.

I'd trying to insert an external loop between stations 1 & 2, OR between stations 2 & 3.  The send-receive jacks are closed circuit, such that when no plugs are inserted station 1 goes directly to 2, or alternatively station 2 goes directly to station 3.

So far so good.

I'm sure a 4PDT would make life easy, but my toggles top out at 3PDT.  Is there a wiring scheme, using a 3PDT, where I could insert the send/receive jacks before either station #2 or station #3?  I'm convinced - perhaps naively so - that my failure to come up with a wiring scheme is because I'm picking the wrong contacts to serve as "commons".  Or is this something that could ONLY be addressed by a 4PDT or pair of DPDTs?

ElectricDruid

Re: Shifting the position of a loop-select
« Reply #1 on: July 24, 2022, 04:44:53 PM »
Sounds possible to me.

After all, there's only two places the outputs can be, either between 1&2 or between 2&3. And there's only two contacts required; send and return. So it should be possible with a DPDT.

Send goes to first pole, the two throws select between output of effect 1 and output of effect 2.
Return goes to the second pole, the two throws select between the input of effect 2 and the input of effect 3.

Make sure to wire the send/return jacks so that with nothing inserted the signal is passed straight through so it makes no odds which position the switch is left in.

HTH

<edit> I'm forgetting the need to connect the "unused" throws, so it *does* need at least one more pole. My bad.
« Last Edit: July 24, 2022, 05:22:25 PM by ElectricDruid »
  • SUPPORTER

Processaurus

Re: Shifting the position of a loop-select
« Reply #2 on: July 24, 2022, 04:57:02 PM »



Does this work for you Mark?

ElectricDruid

Re: Shifting the position of a loop-select
« Reply #3 on: July 24, 2022, 05:19:55 PM »
Actually, thinking about it, isn't the simplest option just to put both loops in place with jacks and then normal the jacks through so that if nothing is inserted they're disabled? Is a big switch actually any simpler than two more jacks?

You could even do it with TRS jacks like some studio gear uses for send/returns, if space is an issue.

Mark Hammer

Re: Shifting the position of a loop-select
« Reply #4 on: July 24, 2022, 05:52:24 PM »



Does this work for you Mark?
I think it works, Ben, so many thanks for that.  I have to follow it through scrupulously, but at first blush, yes it does.  And, as Tom/Druid suggests, the send/receive jacks are normalled to provide direct feed from one to the other when nothing is plugged in.

I should add that it *could* be easier if there was two sets of send and receive jacks.  The reason I'm doing it this way is because  I have a lovely predrilled and powder-coated 1590DD that the production manager at Diamond Pedals graciously gave me when I visited about 5 years ago, which committed me to the number and location of holes.

At the same time, being able to shift an outboard pedal after either #1 or #2 (as well as either before #2 or #3), with the simple flick of a switch is pretty useful.  Given that the 3 circuits included aredifferent kinds of distortion, being able to move an EQ pedal or other filter around is useful.
« Last Edit: July 24, 2022, 05:55:39 PM by Mark Hammer »

Processaurus

Re: Shifting the position of a loop-select
« Reply #5 on: July 24, 2022, 06:44:03 PM »



Does this work for you Mark?
I think it works,

I thought so to, but it is squirrely going through the switch states.  One possible issue is distortion #2 has potential to oscillate at high gain, with the ins and outs having long floating wires attached and acting like antennas, and crammed in together close, it may be helpful to shield the input wires with some coax internally.


Mark Hammer

Re: Shifting the position of a loop-select
« Reply #6 on: July 24, 2022, 06:48:24 PM »
I thought so to, but it is squirrely going through the switch states.  One possible issue is distortion #2 has potential to oscillate at high gain, with the ins and outs having long floating wires attached and acting like antennas, and crammed in together close, it may be helpful to shield the input wires with some coax internally.
Can do.  Thanks for the advice/warning.

MikeA

Re: Shifting the position of a loop-select
« Reply #7 on: July 24, 2022, 07:15:09 PM »
If you use TRS to TS cables for your sends/receives, you can use one TRS jack in each of your enclosure holes (Switchcraft N114Bx or Neutrik NMJ6HC-S).  No switch required.  Two holes = two send/receive loops.  Other end of each cable breaks out from one TRS to two TS for your remote pedal in/out jacks. Both of these jacks are normal-thru switched and insulated. Sketch attached, In and Out are the connections to/from your existing circuits, TRS is the send/receive.

  • SUPPORTER

PRR

Re: Shifting the position of a loop-select
« Reply #8 on: July 24, 2022, 11:30:49 PM »
TRS jacks are obvious but jackery is distracting on stage (even on patio). "Where's the hole??" I can see why a 1-finger switch might be preferred.

I have re-drawn Ben's plan, I hope faithfully. I put the switch units all going the same way like a real switch. Then traced the routing in both conditions.

It "looks" correct. Ben's comments about squealing are on-target. I don't think any inputs are left floating for macro-time, but they may SQUEG!! in the millisecond of switching.

I would not be the one to wire this correctly first time, or solo.

  • SUPPORTER

Mark Hammer

Re: Shifting the position of a loop-select
« Reply #9 on: July 26, 2022, 09:46:08 PM »
First, many thanks to you all for your willingness to take on this challenge.  It's a puzzlement all right.

I redrew Paul's diagram as a graphical representation of how the actual switch lugs would be wired.  I think it's correct.  But I'll have to try it out to verify.



PRR

Re: Shifting the position of a loop-select
« Reply #10 on: July 27, 2022, 01:34:30 AM »
Nice use of colors.
  • SUPPORTER

Mark Hammer

Re: Shifting the position of a loop-select
« Reply #11 on: July 27, 2022, 08:00:05 AM »
I figure that, after all the work YOU did, I had to contribute something:icon_lol:

ElectricDruid

Re: Shifting the position of a loop-select
« Reply #12 on: July 27, 2022, 08:45:40 AM »
I figure that, after all the work YOU did, I had to contribute something:icon_lol:

LOL!