true bypass loop switching: activate 2 loops at the same time?need ucontrollers?

[add4]

I would like to have a true bypass loop that has :
input 1 -> send 1 -> return 1 -> out 1
input 2 -> send 2 -> return 2 -> out 2
there would be one footswitch to activate loop 1 and another one to activate loop 2. no problem until now.
I'd like to have a third footswitch that activates loop 1 AND loop 2. I'd also like to be able to press the loop1 switch when loop 1 and 2 are activated, and that would deactivate loop2, but loop 1 would still be turned on..

I'm quite certain that the last constraint definitely prevents me to use mechanical switching. So i'm getting curious about the ways one can do electrical true bypass switching, and if those who are experienced in that see a way of making what i'd like to do here..
I hope i won't have to use micro controllers to do something like this ..

Another question : with electrical switching, it's possible to use simple 1PST latching switches to control bypass? then the loud clicking noise disappears, right? that's a cool feature for me and adds even more to my interest for this problem...

[amptramp]

You can build a true bypass junction box with a switch and input and output jacks in it and connect this to effects in series so that this switch bypasses both effects at once.  Then when effects are on, you can switch them on or off individually.  If I understand you correctly (not necessarily a given here), this does what you want.  Some people here (like Nikolay) have done switch boxes that have a number of true bypass connections in a box so the pedal can be left on and all switching done from one box close to the player.

[add4]

Not exactly what i want to do ..
i want two loops like what you describe.. into one enclosure. one switch to activate each loop, that's easy.
then one way to turn on these two loops with one switch (that's possible : 4PDT and millennium bypass for the led)
but also, when the switch that activates both loops is on, pushing on say the loop 1 switch would deactivate loop2.. which is, according to me, impossible to do with mechanical switching..

Would anyone have a link to a theory/examples of electrical switching circuits?

[mmaatt25]

These two links may help.  What you want sounds pretty easy using a CD4017/CD4066

http://www.diystompboxes.com/smfforum/index.php?topic=96014.0

http://www.diystompboxes.com/smfforum/index.php?topic=95572.0

[Quackzed]

I'd also like to be able to press the loop1 switch when loop 1 and 2 are activated, and that would deactivate loop2, but loop 1 would still be turned on..

you could doit all with mechanical switches, except for this one... but if both loops are on, you could just step on loop 2 to get the result of loop 1 still turned on... it just requires that you step on loop 2 rather than loop 1 to get there... just seem easier than a whole electronic switching deal...

[Seljer]

You could do the switching logic with flipflops and regular logic chips.... but it'd be like four times smaller and much much easier to do with a simple 8 pin microcontroller.

The actual bypass can remain mechanical though (relays).


edit: my current best draft of this has me using 10 AND gates, some diodes and a dual flipflop. Thats four 16 pin chips
edit1: 8 AND gates + a dual flip flop + many diodes, so three ICs alltogether, I can sketch it up if you wish

[add4]

I'd love this!!!! and i don't know anything about components like this .. flip-flops and AND gates.. are they build in ics ? i have absolutely no idea.. at first i thought you only had opamps in the dil8 package .. then i found out about delay chips, voltage pump chips ... so i guess there are a lot of other things i don't know..

would it be possible to use only latching SPST switches for this then? clicking one switch would send an impulse which would change the 'state' of one bypass circuit.. i guess..

You could do the switching logic with flipflops and regular logic chips.... but it'd be like four times smaller and much much easier to do with a simple 8 pin microcontroller.

The actual bypass can remain mechanical though (relays).


edit: my current best draft of this has me using 10 AND gates, some diodes and a dual flipflop. Thats four 16 pin chips
edit1: 8 AND gates + a dual flip flop + many diodes, so three ICs alltogether, I can sketch it up if you wish

[R.G.]

There is an entirely electromechanical patchable loop switcher shown at geofex.com. See "a programmable footswitch switcher". The link to it is on the first page, fairly far down. I did this some years ago.