Tubemeister 36 Combo - which footswitches?

Just thinking about getting a footswitch for channels and for effects but I can only find a manual for the tubemeister 36 rather than the combo. Which footswitches are compatible and do they do different things? Do I need one for channels and one for effects? Is the effect one worth getting?
I’ve seen a two switch; a three switch and then a FSM 432. Will they all work with the Combo and what is the difference between them?
Thanks for any help

Hi Graham.  For your TM36 the least you need is a double switch type for the channel selection.  Having two switches to control the channels may seem a little odd at first but it works as follows.  One switch is used to swap between (Clean) and (Crunch or Lead).  The other switch swaps between (Crunch) and (Lead) for when that is selected on the other switch.  It isn't the normal way of doing it but, with 3 channels, you have to have that sort of setup.  It allows you to swap between a) Crunch and Lead (switch 2), or, depending on which of those is selected on switch 2, between b) Clean and Crunch (switch 1) or between c) Clean and Lead (switch 1) all with a single stomp.

These switches have to be both on a TRS type stereo jack plug with the (Clean) / (Crunch or Lead) selection on the tip and the (Crunch) / (Lead) selection on the Ring.  The ground is on the Sleeve terminal and is common to both.  You have a similar setup for another double footswitch option to turn both Reverb On/Off on one switch and Fx Loop On/Off on the other.  I have used that setup with my first H&K amp which was a TM36 too.  It is pretty simple to use and is tidy on a small pedalboard.

I now use a FSM432 with my current GM36 as that has full MIDI functionality.  Your TM36 does not have the same spread of options, (control of all front panel control settings), though the FSM432 will work with the TM36 and acts just as the two double footswitches would controlling Channel selection and Reverb and Fx Loop but it adds in control of the Power Soak too which can be useful to kick up the level.  However the FSM432 isn't cheap so that may be more money than you need to spend.

Just get any footswitch which offers two switches on the same TRS jack plug and it will work.  If you aren't gigging heavily there is little need for anything following a "Victorian Engineering" approach, (in a 5mm thick cast iron case), despite what some people will advise nowadays.  (If it isn't in 3 figures it isn't worth having. )  Here is one as an example of how cheap they can be.  Thomann FS2  That "FS2", FootSwitch 2x switches, number designation seems to be pretty common amongst other makers too.  These have no LED but the amp shows what you have selected and LEDs can easily be wired in if you are able to just drill a small hole, glue one in place and solder a pair of wires to the switch and the legs.  There are instructions on how to do this on the forum.  If it helps I can look them out.

Thank you, that’s really helpful. At that price I will order one and give it a go!

Don't forget to let us know how you get on. It's a simple thing to implement but it is useful for others to know that you had no problems. (Or the opposite of course.)

Can I use usual pedal (ehx big muff), as a footswitch on my hk tubemeister 18? Lead boost do nothing for clean channel, so I dont need to switch that boost because I prefer keep it turned on with distortion anyway. I can say that big muff works fine as footswitch, but I worry that even on clean channel, "channel" button lights a little. Have no possibility to buy real footswitch now

I am assuming that your problem is the you cannot control or switch anything on the amp other than manually using the amp's front panel controls.  You certainly can't use the Big Muff as a control pedal to change anything on the amp if that is what you meant.  The signal to change the Channels or turn on the Reverb and Fx loop is a simple DC voltage.  Your BM cannot supply that.  However, there is nothing wrong in still using it as a distortion pedal as it was designed for.  You just have to be careful with the amount of distortion it produces and how much extra distortion it forces the amp to make in its input circuitry.  Too many sources of distortion can lead to a very messy cluttered sound.

Start off by making sure you keep the Volume control of the BM set fairly low.  That isn't "silly low", just low enough so it doesn't hit the input circuit of the amp too hard.  There is more than enough gain inside the amp to drive itself hard with even a mild input signal.  Set your BM Sustain to the level of pedal distortion you want.  This can be really mild with the Sustain down just below clipping and the Volume a bit higher to compensate, more like a simple Boost pedal.  Select the Clean channel on the amp and set its Gain to fairly mild.  Then slowly increase the BM Volume turning the amp Volume down a little from time to time, to make the input signal to the amp high enough to push its input circuitry into overdrive.  That won't make the BM produce any more distortion, its signal stays the same and just gets bigger.  It is the bigger signal driving the H&K input circuitry into producing distortion.

That is NOT the same thing as getting the valves to overdrive.  The H&K amps have a very clever solid state input buffer circuit which acts like a perfectly clean boost before the valves, as a mild warm overdrive, or as a full on Tubescreamer type distortion pedal depending only on the level of signal you feed into the amp.  It sits before any of the amp's controls so it is entirely dependent on the level out of of the last pedal in the chain or out of your guitar if you are feeding direct into your amp.  You can find a description of how it works here:  Using The H&K Input Buffer

I'm not sure what you mean when you say the Channel light is on a little even on the clean channel.  I don't have the TM36 schematic so I can't see if that is normal but it certainly isn't for the other models and I would have thought not.  The TM18 definitely has its channel LEDs set up for an "Either/Or" action without any chance of cross interaction.

I connected cable from big muff output to footswitch (without power supply). It switches channels, but I worried about this light
Picture 3 - no big muff connected on clean channel (everything ok)
Picture 2

- distortion channel switched by big muff (everything okay too)

The only problem is that you are doing something - errrm - well - stupid! You should never connect anything together unless you know it is a reasonable match and there is a chance it will work. Here there is no chance at all that combination will do anything useful. You are lucky that you didn't damage something, either in the amp or in the pedal. You are trying to make the pedal do a job it was never designed to do. It is a signal processor which makes changes to the signal you feed into it. It certainly isn't in any way a controller of the DC voltage the amp feeds to it on the channel of effect jack connectors. You have just put a large DC voltage straight onto the output of your pedal circuit and it won't want you to do that. It's a bit like connecting your mobile phone headphone output to the amp and expecting to control that somehow. Would you expect that to work?

Don't worry about the lights, under those silly conditions it will be exactly what should be expected if you do that, it's just a waste of time trying it. Oh - and best not do it again!

Thanks

I'll round this one off with a "why you shouldn't do this thing which is terribly unusual".  It may help other people too.

The control signals for the channel/effects changes are fed from the H&K amp to their pedal switches through a resistor.  The amp "listens" to the end of that line to see whether there is the same voltage it supplies on it when the switch is open, or whether this drops to 0V when the switch in the foot pedal connects it to ground.  In the Big Muff the last component is the Volume control so the H&K control line will be attached to that.  When the Big Muff has nothing in its input jack and it is switched to be in bypass mode, (pedal distortion is off), the output line is connected directly to ground through the input socket.  It has a definite 0V on it which the amp understands.  When the Big Muff is switched into circuit the H&K control line is then connected to ground but through the Volume control.  The setting on the volume control will alter the voltage on that line and the H&K amp is seeing it as "part turned on", it isn't fully up or fully down.  There is very little chance that the channel will switch like this as the switching relay has most likely not reached a voltage where that can happen, the setting on the volume control will dictate that, but the LED is made to glow dimly as that is in line with the relay coil.  So basically, not enough voltage to activate the relay but enough to make the LED glow.

Now the bad part.  If the Volume is set high up you will be putting a reverse voltage across the output capacitor of the Big Muff.  In this case it should be fine as it is most likely a type which can take voltages both ways but some definitely won't like that!!!  It obviously has not been damaged this time but that is more by good luck than good judgement.  It's not a good thing to do.