Footswitch not respecting "EQ Off" channel settings.

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Angle Loss
Bottle Rocket
Posts: 11
Joined: Fri Nov 14, 2014 10:03 pm

Footswitch not respecting "EQ Off" channel settings.

Post by Angle Loss » Tue Sep 03, 2019 4:26 pm

Hi all,
I contacted M/B, but was told to just take it to a tech which I cannot afford to do. Here are the symptoms:

The foot controller doesn't seem to respect the (any) channel EQ setting when the channel is set to off.
-ex. channel 1 has EQ assignment switch set to 'off' and the EQ foot switch is engaged (lit), I would expect that when switched to channel 1 that the EQ would turn off for that channel and reengage if ch.2/3 were on either 'EQ on' or 'EQ FS'.
-if happens for every channel which that state is reached

When the foot controller is unplugged:
-amp (when changing channels) respects switch assignment: EQ on engages EQ. EQ 'off' or 'FS' bypasses EQ. (normal?)

I bought a second cable and it produces the same outcomes, therefore I believe it is either the foot controller or relay/s in amp.

How can I figure out what part is producing the problem? I'm a hobbyist and have built/rebuilt/modded mainly older amps, but the MV is a bit complex for me and I thought someone here would know a lot more off the bat than I do! I have not worked on relay systems. I do understand the risks and warnings of working on amplifiers. I'm hoping to get this going again on my own.

Thanks for your help!

BMW-KTM
Mark I
Posts: 34
Joined: Sun May 24, 2015 2:15 pm

Re: Footswitch not respecting "EQ Off" channel settings.

Post by BMW-KTM » Tue Sep 03, 2019 9:32 pm

OK, so you have channel one in which the (5 band) EQ is set to off and another channel in which EQ is set to F/S.
Am I right so far?
And when you use the floorboard to switch to channel one the EQ LED lights up on the floorboard.
Have I got that correct?

My question, is the EQ actually engaged? Or is it just that the light is on?
I'm wondering if it's possible it's just that the foot switching gear isn't "smart" enough to bring the lights in line but the actual EQ is doing what is asked, even though the lights may seem to indicate otherwise.

When you unplug the foot controller and use the toggle on channel one does the EQ actually switch in and out?
Or is that switch not functioning correctly?
If you're not sure, make a more drastic setting on the EQ and try again.
If that switch is working then plug the controller back in and compare the sound of channel one (EQ switch @ F/S) with the EQ-off sound you got with the controller unplugged.
If the setup works properly and you are in fact getting the sound you want then I wouldn't let a little light that's not getting with the program bother me.

dakocha
Bottle Rocket
Posts: 4
Joined: Tue Mar 26, 2019 2:02 pm

Re: Footswitch not respecting "EQ Off" channel settings.

Post by dakocha » Thu Sep 05, 2019 2:53 am

It's a common issue. Try engaging the EQ while pulling the footswitch cable up on the amp side and it should work. If that doesn't work try the fix mentioned here: http://www.dirtyhurricane.com/gear/Mesa_FTSW_FIX.pdf

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Don
Single Recto
Posts: 1364
Joined: Sat Jan 12, 2008 12:32 pm

Re: Footswitch not respecting "EQ Off" channel settings.

Post by Don » Thu Sep 05, 2019 7:11 am

Yep. I just came here to say to check the grounds on the footswitch cable.

BMW-KTM
Mark I
Posts: 34
Joined: Sun May 24, 2015 2:15 pm

Re: Footswitch not respecting "EQ Off" channel settings.

Post by BMW-KTM » Thu Sep 05, 2019 7:47 am

Good to know.
Thanks, guys.

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