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No, I can't remember if it's the capacitance or something else but a speaker cable uses a different type of cable than an instrument//footswitch cable.
 

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You don't know until you look, but it is likely footswitch cable would be the same structure as an instrument cable. These are very low power level cables with thin signal wire(s) as core and thick shielding as surround. They don't and can't carry a lot of current (ie "power") without significant loss (ie too high a resistance due thin core wire size).

Speaker wires are two identical sized conductors to carry lots of current to and then, on the other wire, back from the speaker (return) symmetrically. They are typically thick enough for low loss at high currents.

At low speaker levels, it doesn't matter. At non-quiet levels, should definitely use speaker wire for speakers.

There is also an impedance match discussion, but above covers all practical matters.
 

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Footswitch cable is usually the same as guitar patch cable (coaxial aka single conductor + sheild). So no.

Yes capacitance is a part of it (causes high end loss, like half a crossover)

All that said if the cable is really short (a foot or 2) it may not make much (audible) difference.

edit: @LexxM3 beat me to it.... but capacitance is an issue at all volumes.
 

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Lexx is pretty much in the ballpark. The sorts of cables we are accustomed to seeing don't have much linear resistance (i.e., ohms per foot). But the thing is that when an amp expects to see 8ohms, and the cable has added 3ohms on top of that, that can extract less than optimal performance out of the amp. Remember, it doesn't "know" that the speaker is different than the cable. It just sees a total undifferentiated load on its output. So you want to make whatever you connect the speaker/s to the amp with to be as short and thick as possible, to reduce the cable to as negligible a part of the overall equation as possible.

I'll just note that we have no idea what you meant by "footswitch cable". Depending on the amp it was for, that can imply different things. For instance, many amps cancel reverb by simply grounding the reverb signal. But since that means the cable is carrying audio, it will be shielded, and not particularly heavy gauge. The shielding aspect isn't a real problem, but the guage will likely be thin enough to add greater load.

Again, when sending a guitar signal over a 20ft cable, having that cable add, say, 4 ohms, doesn't change much. But stick that same cable between the amp output and speaker, and it's a whole different ballgame. Sixteen-gauge zip-cord is your friend.
 

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All good answers here, the only question that remains is "which footswitch cable"?

My Fender/Sunn absolutely has to use a speaker cable for anything more than a couple of feet, because it uses some complicated diode network to allow 3 footswitches using only one cable pair - and I suspect extra capacitance messes with their 'logic'. But a couple of other amp's footswitchi don't work well with speaker cable. So the question is: What kind of cable is yours?

Nothing magic about speaker cables, low enough impedance for the distance you're running and enough copper to carry the current your going to be passing through it. The rest is just snake-oil.
 
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Discussion Starter #7
Good. I'll build one then, from lamp cable.

I asked, because I seem to remember being told, that a footswitch cable was no good for an instrument. I guess I'd have to splice it open to be sure.
 

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My Fender/Sunn absolutely has to use a speaker cable for anything more than a couple of feet, because it uses some complicated diode network to allow 3 footswitches using only one cable pair - and I suspect extra capacitance messes with their 'logic'.
Interesting; sounds like that amp isn't sending a binary signal like most footswitches, but rather a control voltage. Kinda like the remote for my AKG BX25 reverb.
 

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Interesting; sounds like that amp isn't sending a binary signal like most footswitches, but rather a control voltage. Kinda like the remote for my AKG BX25 reverb.
Yea, it's analog. It uses different zeners to drop the voltage supplied by the amp in a number of steps to control the 8 different combinations and permutations. A very complicated design just to save money on cable and the use of non-standard connectors, like Midi (and like Mesa and others do).

I bought 2 extra Sunn footswitches cheap used (because they have a limited target market) to have a spare. Neither worked so I robbed parts to make one working unit. That was not an easy project, as it turned out. The other f/S recently became the donor hardware for my 3 button footswitch for my mod'd Mesa LSS with the footswitchable Drive option. I basically gutted it and used just the switches, LEDs and PCB. I use one stereo and one mono cable because it worked and I always have those cables around.
 

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Hmmmn, I don't think I wanna go down that road, but it is rather well timed info given that I am currently designing myself a little tube dirt machine to sit on top and in front of my amp, and looking at relay switching vs sending actual signal down a footswitch cable. I wanna keep it simple; cable and connectors are cheaper than dev time. I am actually considering 120VAC octal socket relays because a) I won't have to redesign the power supply , they can run off of the line in front of the pwr tx (like some amp makers, e.g. Garnet, did with their pilot lights vs loading down the filament supply; also cheaper parts, at least now, maybe not then) and b) will look cool with the other tubes, and c) they have a built in indicator light so I don't have to deal with that either (so can use DPDT instead of 3PDT.... though if using AC lights I can diasy chain it off the relay coil - so I have options if I can't get relays with an indicator anymore at some point). Problem is they are pricey, and the indicator ones are rare (a lot seem to be getting discontinued) but I managed to score a small batch of them for $5ea (even a 6VDC relay would be about $3.50-4) on ebay so I can afford to blow one testing the idea and still have spares or enough to build a second unit.
 

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For what it's worth, just checked one of my Mesa stock footswitch cables and that one was, in fact, speaker wire both by direct inspection and by markings on the cable. Of decent gauge too.
 

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For what it's worth, just checked one of my Mesa stock footswitch cables and that one was, in fact, speaker wire both by direct inspection and by markings on the cable. Of decent gauge too.
Yah, it happens. That's why I raised the matter of what type of footswitch cable. There are so many different protocols and methods used for remote footswitching that simply calling something a footswitch cable doesn't really specify enough.
 

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That's why I raised the matter of what type of footswitch cable.
All that I remember, is that it IS a footswitch cable. Fender maybe, could be Crate ... or Vox ? Really don't remember, but it doesn't matter, I built a new one from scratch.

Thanks everyone.
 

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All that I remember, is that it IS a footswitch cable. Fender maybe, could be Crate ... or Vox ? Really don't remember, but it doesn't matter, I built a new one from scratch.

Thanks everyone.
Unless it is a molded style cable ( dual ended plugging into the floor box vs perm attached) it is easy enough to check by either unscrewing the jack end or looking in the floor box to see if it is 2 conductor wire or single + shield.
 

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Hmmmn, I don't think I wanna go down that road, but it is rather well timed info given that I am currently designing myself a little tube dirt machine to sit on top and in front of my amp, and looking at relay switching vs sending actual signal down a footswitch cable.
I'm not sure if you took my explanation wrong, or if this is unrelated to my comments.

In that Sunn amp, no audio signal goes down the footswitch cable (which would be noisy, since it's unshielded). I just meant that the control of the amp is done through analog control voltages, not hi/lo; on/off; 1/0 digital type control that separate conductors for each switch would provide.

So imagine the amp has a 12V source at the footswitch jack and the footswitch is configured to drop that voltage 8 times at 1.5V steps. So 12V (open circuit at FS) would be no buttons pushed = Channel 1, loop off, reverb off. First button pushed would drop the amps voltage to 10.5V (one resistor diode combination engaged) and would indicate channel 2 on amp, loop off and reverb off. That button released and second button pushed would enable a diode resistive circuit to drop the voltage by 3V to 9V, indicating channel 1 but loop engaged and still no reverb. Button 2 released and 3 engaged would drop 4.5 volts (so 7.5 at amp) and would indicate channel 1, no loop but reverb engaged. And so on through the 8 potential analog voltages / 8 discrete settings via the footswitches. I don't remember the actually voltages and steps but this is the general idea of how it worked.

So it's only analog control voltage on the cable and not audio. Sorry if I wasn't clear earlier.


And yes, in retrospect, my TA15 was supplied with a nice long speaker cable for it's one button footswitch (channel change only) - as that only requires one pair of wires to transmit the channel change information digitally (1/0; high/low; open/grounded).
 

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I'm not sure if you took my explanation wrong, or if this is unrelated to my comments.

In that Sunn amp, no audio signal goes down the footswitch cable (which would be noisy, since it's unshielded). I just meant that the control of the amp is done through analog control voltages, not hi/lo; on/off; 1/0 digital type control that separate conductors for each switch would provide.
Yeah, I got that it's not signal going to the footswitch but a control voltage. I just don't wanna mess around trying to come up with a voltage scheme like that because I only have 2 items to switch so standard mic cable (or stereo interconnect cable as used on older, non-fender Sunn and Musicman amps) will work (and I have enuf of that laying about) so I can afford to go the simple open/closed circuit way vs something as complicated and involved as your Sunnder, as interesting as it is. .... although, (shit, here goes my brain again) I still am missing the footswitch for my Sunn 1200s (not the fender-made bass amp, the 70s tube guitar head) which is exactly that type of switch (rca connectors, stereo interconnect/dual coax, wire).... I don't wanna have to switch that back and forth or have 2 seperate switches, so I could use something like miniature snake cable and make a switch for both heads.

It is a dual molded end plug model, so no way to know unless I tear it apart.
Ain't that the way; better be safe and just get the right cable to be sure (as you already decided above).
 
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