Double D? Has anyone built this in a rackmount preamp version?

[jimosity]

I'm really digging the tone clips on the runoffgroove.com site for the 'Double D' and I really like the idea that it's two channel.

Has anyone built this 'Double D' in a rackmount unit?  That's what I want to try, but I'd like to see some pics of others that have already been built if possible.

Also, instead of switching channels via footswitch, I want to replace the switches with 1/4" jacks to control switching via 1/4" jack, I assume that should be pretty easy, am I right?  (I'll be using an Axess Electronics GRX4 to switch channels, or a TC Electronic G-Major)
Can somebody tell me the quick and easy 1/4" jack replacement for the switches?

[jimosity]

BUMP.
I've got the Double D all wired up and the board is populated except the switch, can somebody please help me figure out how to replace the footswitch with a 1/4" stereo jack to allow for channel switching?

[Seljer]

If you want true bypass from afar then relays are the way to go

[jimosity]

Yeah?
Where can I find an easy to understand relay diagram to put in place of the switch for the Double D?

[Seljer]

well just get a 9V DPDT relay (or whatever voltage you're running the unit from), use the switch part of the relay like you'd be working with a normal switch

then for the relay coil, hook the + end up to 9V, then for the other end, hook it up to the tip or the ring part of the 1/4" jack, the sleeve of the jack goes to ground
if you can't get 9v relays then use ones for a smaller voltage (5v) and wire an appropriate resistor in series, find out the internal resistance of the relay coil and work out what resistor you need

so when the footswitch connects the ring and the sleeve together, the relay turns on

[MartyMart]

http://www.pbase.com/martymart/amp_rack_birth&page=all

Not a Double D , but three jfet preamps and a speaker sim in a rack !
Works a treat, each switchable from dpdt switches and powered from a 9v Boss PSU
Various build photos and finished rack.

[oldrocker]

I don't know about making it a rack mount but I know I have been seriously thinking about building that bad boy.  It's like getting to pedalsin one build.  As for a rack version I say why not?  Just add a couple of remote foot switches to bypass and switch between the two effects.

[jimosity]

I've actually got it built into a rackmount casing and am 99.9% done with it, but can't seem to figure out exactly what you just said; how to channel switch / bypass via 1/4" jacks instead of footswitches...
Somebody mentioned relays and that may be the correct answer, but I'm so new to all of this stuff, I haven't got a simple answer as to HOW to use relays with this particular project specifically.

I went ahead and wired it up with a DPDT toggle switch to test it out, so I should have it done tomorrow at the latest to see what it's like...if all goes right...

[mars_bringer_of_war]

http://www.pbase.com/martymart/amp_rack_birth&page=all

Not a Double D , but three jfet preamps and a speaker sim in a rack !
Works a treat, each switchable from dpdt switches and powered from a 9v Boss PSU
Various build photos and finished rack.

Marty, can you explain how you handled the switching? I've been trying to figure out a way to do pretty much what you have there, but would need three independent "channels", switching between the three, but not needing any real bypass.

[DiamondDog]

I went ahead and wired it up with a DPDT toggle switch to test it out, so I should have it done tomorrow at the latest to see what it's like...if all goes right...

Grasshopper,

http://www.geofex.com

has a lot of information on that you seek. Sometimes it is buried, but it is there. Including multiples of multiples, and I am sure there is something for remote control of drummers buried in there somewhere.

However, in really, really REALLY simple terms-

What is the difference between a DPDT switch and a DPDT relay? For one you move a lever, for the other you use a current to move the lever. That's it.

So think in terms of having a DPDT relay (if you need DPDT- I haven't looked at the circuit) where you are putting your switch and using current, not fingers to move the lever.

The mono jack has + and - which you can run to your relay activators, getting the power from where ever on your circuit. A mono 6.35mm plug has + and -, as does the cable.

Run that out to a remote switch, under your feet; when you shut the switch, you complete the circuit, relay shuts. Open the switch, open the circuit, open the relay.

Move the plugs and jacks up to stero, upgrade the cable appropriately, you may control 2 circuits if you use 2 switches, or have an LED indicator that says the effect has switched (not the switch).

You can move on up to optos, you can change to ICs, you can do it many ways. But for simplicity, start this way and develop your understanding.

Go Grasshopper. You have enough to dream of an answer. When you can catch a minor 3rd in your chopsticks, you are at one. 

[MartyMart]

Marty, can you explain how you handled the switching? I've been trying to figure out a way to do pretty much what you have there, but would need three independent "channels", switching between the three, but not needing any real bypass.

Well, this was an easy one, as it's more for "studio" use.
Input jack does power up as normal.
-> first circuit with dpdt to -> next circuit etc to speaker sim and then output jack.
So, any effect can be "on" and the spkr sim can be on/off.
They were not ever meant to be run in series, so only one of the circuits & sim will
ever be used, just a choice of three Jfet sims.
Circuit 1 is the Supreaux and circuit 2 is my Bassman sim, these work quite well into
each other, almost clean supro boosting the bassman sounds great !! a happy accident

See layout gallery from Dragonfly, for multiple circuit wiring, it's quite simple.
I could have added some millenium bypass circuits for an LED to see what's active, but it's easy to
see the switch "up and on" position, as they are toggle switches .

MM.