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philipjoyce

Any solutions for the Mesa Ext Amp Switching problem ?

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Im Using a Mesa Formula preamp and it has 1/4" jacks to switch Rhythm/Lead1 , Lead2 and EQ . 3 mono jacks and a regular stereo footswitch will switch between Rhythm/Lead1 and Lead2 and i assign EQ to Lead2 automatically so i figured that the Helix would be able to switch just the channels using its EXT AMP control. 
Now it does switch the channels but theres some weird issue where when i set a footswitch to control the Tip switching it does engage the Rhythm channel but when you turn it off it should change to Lead1 and the light does light up on the preamp but no sound comes out. 
If i then turn on the Ring switch it turns on Lead2 and that is fine. 
it seems to be an issue with the 2 channels that share the 1 1/4" jack. 
Very Frustrating. I'm gonna have to bring the mesa footswitch to my gig for the moment til i can figure this out. 
Have seen some people recommending the NUX PSM-2 Midi remote switch to switch channels via midi.

Can you set a footswitch on the helix to send out midi instructions ? 
 

Thanks for any help or suggestions. 

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I had problems with my Friedman BE100 while switching channels via EXT Amp out (helix espession pedals got crazy ) , but made by myself one of those 9v powered relay switchers and now it works great. Anyway had to reduce voltage to 4V on 5v relays and it works great now :-).I've got some schematics if you are interested.. Also use  moded CV out with help of tiny FED transistor (hidden in jack plug) , to switch my HBE booster on Friedman.. Also works great..

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I had problems with my Friedman BE100 while switching channels via EXT Amp out (helix espession pedals got crazy ) , but made by myself one of those 9v powered relay switchers and now it works great. Anyway had to reduce voltage to 4V on 5v relays and it works great now :-).I've got some schematics if you are interested.. Also use  moded CV out with help of tiny FED transistor (hidden in jack plug) , to switch my HBE booster on Friedman.. Also works great..

 

have you a link to how you did that with the CV out ? 

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The NUX PMS-2 looks like it works like my RJM Amp Gizmo by saving the switch state to whatever MIDI program change (PC)/patch (0-127) the MIDI controller is on.  There are conveniently 128 Helix presets in each setlest to correspond to the 0-127 typical MIDI program patches.  You can also change Helix default alpha-numeric patch numbering to numeric MIDI type (see pics).

 

For example, Helix patch 01D will send MIDI PC 003.  So basically setup a Helix preset and the desired switches on the NUX PMS-2, then press Save on the PSM-2.  Then when you call up that Helix preset, the PSM-2 will receive the corresponding MIDI PC to the Helix preset and recall the switch state.

 

And dang, $41 on Amazon for the NUX PMS-2?  I would certainly grab one if I didn't have two RJM amp Gizmos already.  Sure would beat building a relay box!  Anyway, all of my amps need 4-8 switches, so I never thried the Helix EXT AMP control.

 

http://www.amazon.com/docooler-Switcher-Control-Function-Portable/dp/B00NXPMFMU

 

Update...and the PSM-2 is around $30 on eBay...seems like a no brainer if it really works with no noise or hum.

post-1189006-0-72802800-1462472001_thumb.jpg

post-1189006-0-29529200-1462472005_thumb.jpg

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The NUX PMS-2 looks like it works like my RJM Amp Gizmo by saving the switch state to whatever MIDI program change (PC)/patch (0-127) the MIDI controller is on.  There are conveniently 128 Helix presets in each setlest to correspond to the 0-127 typical MIDI program patches.  You can also change Helix default alpha-numeric patch numbering to numeric MIDI type (see pics).

 

For example, Helix patch 01D will send MIDI PC 003.  So basically setup a Helix preset and the desired switches on the NUX PMS-2, then press Save on the PSM-2.  Then when you call up that Helix preset, the PSM-2 will receive the corresponding MIDI PC to the Helix preset and recall the switch state.

 

And dang, $41 on Amazon for the NUX PMS-2?  I would certainly grab one if I didn't have two RJM amp Gizmos already.  Sure would beat building a relay box!  Anyway, all of my amps need 4-8 switches, so I never thried the Helix EXT AMP control.

 

http://www.amazon.com/docooler-Switcher-Control-Function-Portable/dp/B00NXPMFMU

 

yeah that little box does look like it could be very useful.

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The guy is forum member -Doughadfield..

 

Check his post started with word: ANSWERED!!

Sorry for some reason I can't copy paste text to this forum window :-)

Cheers,

jacek

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Hello Gents,

Here is a pictorial on how the CV MOD for Amp Switching works... (As originally envisioned by Doughadfield)

 

cv_switch.jpg

 

I added a switch to allow you to control one of two functions from the Helix CV... (the TIP or RING on the Amplifier side...)

 

You can mount the FET/ switch in a small plastic box with two 1/4" jacks.

 

I hope this helps

 

seeya

 

Joe

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I used a Voodoo Lab Control Switcher for switching of remote stuff.  It has four fully isolated switches and is controlled either by program change to set all four at once or you can change the switches individually using CC messages. At the minute I'm using it to control the footswitches of a GR-20 and it works perfectly

 

Mike

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I used a Voodoo Lab Control Switcher for switching of remote stuff.  It has four fully isolated switches and is controlled either by program change to set all four at once or you can change the switches individually using CC messages. At the minute I'm using it to control the footswitches of a GR-20 and it works perfectly

 

Mike

 

from chatting to a friend of mine who was using a G-system to change channels on a Mark IV he reckons its something to do with the EXT Amp Control in the Helix sharing a ground ,where the mesa switching requires isolated grounds for each of the switching jacks

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from chatting to a friend of mine who was using a G-system to change channels on a Mark IV he reckons its something to do with the EXT Amp Control in the Helix sharing a ground ,where the mesa switching requires isolated grounds for each of the switching jacks

 

Hey Philip

 

Most Current Production MESA Amps share ground between all of the switching jacks... the problem is that the Helix uses open collector transistors (as opposed to mechanical relays) to switch to ground which most amps don't like... 

 

I guess that the G-system uses the same transistor set-up

 

I hope this helps

 

seeya

 

Joe

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Hey Philip

 

Most Current Production MESA Amps share ground between all of the switching jacks... the problem is that the Helix uses open collector transistors (as opposed to mechanical relays) to switch to ground which most amps don't like... 

 

I guess that the G-system uses the same transistor set-up

 

I hope this helps

 

seeya

 

Joe

 

Yeah its obviously not something thats gonna be fixed with firmware so i guess i'll just figure out a way to do my switching with either a midi device or just use the original footswitch.

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from chatting to a friend of mine who was using a G-system to change channels on a Mark IV he reckons its something to do with the EXT Amp Control in the Helix sharing a ground ,where the mesa switching requires isolated grounds for each of the switching jacks

The "common ground" problem is why I had to use an isolated relay switcher. The GR-20 pedals don't share a common ground so a standard switch wouldn't work. Even the Boss FS-6 units have common ground so they weren't suitable. The Voodoo Lab box was a perfect solution though, and I have a couple of outputs spare for when I want to switch something else

 

Mike

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I searched this forum for "PMS-2" and didn't find anything.

 

I found a post on the NUX PMS-2. While latched mode seems to work fine, unlatched/momentary switching seems to not change with MIDI PC.

 

NUX PMS-2 Midi Switcher | MarkWeinGuitarLessons.com

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Couldnt get my Transatlantic TA15 to change channels until I pulled the jack at the helix end out about halfway and then it works fine. It's a pretty stable connection so I just use it that way and it's not really a problem but I'd like to have it working with the jack fully in if possible. Any suggestions?

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Hey Ricky, 

 

Try using a Stereo 1/4" cable...

 

It looks like you are using EXT AMP Control #1 (TIP) to control your amps channel change; which is on the TA-15 footswitch (RING)...

(The only way to do this is with a mono cable inserted half way  :D )

 

With a Stereo cable, you can insert the plug alll-the-way, but, you will have to use EXT AMP control #2 (RING) to control your TA-15 channel switch.

 

I hope this helps

 

seeya

 

Joe

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Thanks Joe - sounds promising - will give it a go and see what happens

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Hi Joe - took me a couple of days to find my stereo TRS cable. Unfortunately the problem remains the same - will only work if halfway in at the helix end. Any further suggestions?

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Hi Ricky

 

Unfortunately, you have a ground loop... You'll need an external control switcher or a relay interface like this...

 

mk525_switch_3.jpg

 

I hope this helps

 

Seeya

 

Joe

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Joe - it's wonderful to know that there are people out there who know how stuff works. Makes us all feel like no matter what happens some one can sort it out - looks like you're that guy! I'm going to stick with my cobbled together solution of a small rubber grommet on the jack to keep the jack in position half in half out. It's very stable and has worked well on a couple of gigs so far. Not an elegant solution but it works. Thanks for taking the time to answer my question so well.

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Joe - it's wonderful to know that there are people out there who know how stuff works. Makes us all feel like no matter what happens some one can sort it out - looks like you're that guy! I'm going to stick with my cobbled together solution of a small rubber grommet on the jack to keep the jack in position half in half out. It's very stable and has worked well on a couple of gigs so far. Not an elegant solution but it works. Thanks for taking the time to answer my question so well.

 

You're welcome.. I'm glad that you can control your amp...

 

The grommet is a good idea.. I will remember that!

 

seeya

 

Joe

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Add a mesa dual rectifier to the list of amps that DONT work with the helix's ext amp switching,not happy, i concluded that i'd only be able to change one thing on my dual rec due to only having one switch jack but now i cant do anything other than use the one channel on my 3 channel amp!!!!!!!

 

£1200 and ive got to by another box to make this work?!?!?!?!

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Hello Stig, 

 

Unless you want to use an external "Control Switcher" controlled by MIDI (i.e. the Voodoo Lab Control Switcher or the RJM Switch Gizmo)

 

You will have to build one of these with relays to isolate the Helix and the amp...

 

mk525_switch_3.jpg

 

I hope this helps

seeya

 

Joe

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