Tremoverb loop as a second master / solo?

[canon]

Technical question, I didn't want to hijack the thread:
http://forum.grailtone.com/viewtopic.php?t=7048

in that thread there's some clever loop manipulations to make the F-series parallel effects loop work as a master volume by using a shorted return jack. Since the Tremoverb's parallel loop is footswitch-able, would this work on a Tremoverb to, in effect, have another volume option, a-la solo boost (I suspect loop-on would be the lower volume)? I don't want to try it without knowledge, I might blow something up! But it would be very very cool if it worked.

 

[tele_jas]

I don't think I completely understand your question?

The only way I found to get the T-verb to have a "solo boost" was to get the loop modded to Serial and then run a volume pedal in the loop at a lower volume (which was my rhythm volume) and when I wanted a solo boost I'd bypass the loop and bring the amp to normal levels (which was louder since the volume pedal was bypassed). That's the only way I found to get the boost. In the mod from parallel to serial, my amp repair guy replaced one of the jacks with a "shorting" jack?

That's all I know today :wink:

 

[canon]

Hal9000's post implies you can do it with the F-series' parallel loop with just a plain jack and a shorted jack and the mix knob, unless I didn't understand his post?

I don't think I completely understand your question?

The only way I found to get the T-verb to have a "solo boost" was to get the loop modded to Serial and then run a volume pedal in the loop at a lower volume (which was my rhythm volume) and when I wanted a solo boost I'd bypass the loop and bring the amp to normal levels (which was louder since the volume pedal was bypassed). That's the only way I found to get the boost. In the mod from parallel to serial, my amp repair guy replaced one of the jacks with a "shorting" jack?

That's all I know today :wink:

 

[jbird]

I would assume that since this advise from Mesa is only in it's "F" series manuals, that it only applies to the "F" series! You would think, especially as the Tremoverb is part of the "Rectifier" line, that somewhere in one of the "Rectifier" manuals, it would also be mentioned!

 

[hal9000]

Technical question, I didn't want to hijack the thread:
http://forum.grailtone.com/viewtopic.php?t=7048

in that thread there's some clever loop manipulations to make the F-series parallel effects loop work as a master volume by using a shorted return jack. Since the Tremoverb's parallel loop is footswitch-able, would this work on a Tremoverb to, in effect, have another volume option, a-la solo boost (I suspect loop-on would be the lower volume)? I don't want to try it without knowledge, I might blow something up! But it would be very very cool if it worked.

Yes, it ought to work. From the schematic I saw of the Tremoverb's loop, it's the same as the F-series (as are most Mesas BTW) with the addition of the parallel-foot-switched path. I didn't see the switching jack on the FX send jack, but I'm sure it's there. Do exactly the same mod as I designed and the FX Mix pot will act as your master volume, and will be bypassed upon switching the FX loop off.

Good luck!

 

[hal9000]

I don't think I completely understand your question?

The only way I found to get the T-verb to have a "solo boost" was to get the loop modded to Serial and then run a volume pedal in the loop at a lower volume (which was my rhythm volume) and when I wanted a solo boost I'd bypass the loop and bring the amp to normal levels (which was louder since the volume pedal was bypassed). That's the only way I found to get the boost. In the mod from parallel to serial, my amp repair guy replaced one of the jacks with a "shorting" jack?

That's all I know today :wink:

You can get a solo boost the same way with a parallel loop. Just set the FX loop mix to 100% and use the volume pedal as you described. In addition, you can use the parallel loop to better effect by turning the mix down to a low percentage such that the volume pedal only adds 3 dB or so of volume for its entire travel. Then, you have a nice smooth solo boost without having to worry about the minimum position.

 

[hal9000]

I would assume that since this advise from Mesa is only in it's "F" series manuals, that it only applies to the "F" series! You would think, especially as the Tremoverb is part of the "Rectifier" line, that somewhere in one of the "Rectifier" manuals, it would also be mentioned!

I designed the FX Mix Pot master, so don't expect to find it in the manual for the F-series or the Rectifiers.

The FX loops of the F-series and Tremoverb are fundamentally the same, so it will work. If I had a Tremoverb, it would only take me a few minutes to check it out.

BTW, if anybody is curious about this mod, one needs only to find two unused ¼” instrument cables. Insert one end into the FX send jack and leave it dangling (not connected to anything). The other cable needs to be inserted into the FX return with the free end's sleeve and tip shorted. Household Aluminum foil and a rubber band work fine as does an alligator clip. I actually used the little spring loaded clip that's one my work badge. As long as the FX loop is enabled, the Mix pot will now act as a final master over both channels.

 

[canon]

Genius! I'll try it and report back.

 

[Monsta-Tone]

How did it work? The only thing I don't like about my T-Verb (other than the new Mesa tubes the previous owner put in) is the lack of a Solo button.

 

[jbird]

So, I have a couple of questions! 1st, the Tremoverb's and Two Channel Solo's footswitches don't have f/x loop on/off switches? Right? I know my two channel Dual only has one switch, Orange or Red channel! So in the scenario above, how are you switching the loop on/off? 2nd, I see at the Mesa sight, they have several one button footswitches for f/x loops, reverbs, tremolo, etc! Are these to be used with the external switching option? Because the external switching jacks are to be used with Midi devices, or so I thought?

 

[tele_jas]

Here's what I just got to run in the FX loop of my AC30cc. It doesn't have a foot switchable FX loop, so I need to run this in the loop. While engaged, the amp runs at a lower, rhythm volume... when I want a solo I turn it off to bring the amp to normal volume. It'll work, just means more cables to run.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=016&item=260038081497&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

 

[canon]

Well, it worked great for a few seconds, then the amp starting going out intermittently, and now the clean channel is more off than on (2 seconds on, 8 seconds off, kind of thing), and so, not so good.

I used the external switching option, which again worked well for a few seconds, I was really psyched.

I replaced all the preamp tubes with no improvement, so now my potentially 4 channel amp is a one channel amp.

Off to a tech I go.

 

[jbird]

Since the Tremoverb's parallel loop is footswitch-able

Again, since when is the Tremoverb's parallel loop footswitchable? Unless set to "external switching", which then (usually) requires some sort of midi device!

 

[canon]

There's a 'loop' footswitch jack that is a simple 1/4" jack.

 

[jbird]

Where is this jack? Part of the "external switching" jacks? And what would you be using as a switch?

 

[hal9000]

Well, it worked great for a few seconds, then the amp starting going out intermittently, and now the clean channel is more off than on (2 seconds on, 8 seconds off, kind of thing), and so, not so good.

I used the external switching option, which again worked well for a few seconds, I was really psyched.

I replaced all the preamp tubes with no improvement, so now my potentially 4 channel amp is a one channel amp.

Off to a tech I go.

Canon, I'm really sorry to hear you're having problems. I don't understand what happened with your amp? There's nothing you can do to the loop that will cause your tubes to fail. Of course, I can't guarantee that you performed the loop mod correctly, but a bad solder joint, intermittent connection, etc could cause a problem.

The real test here is to take the two cables (or whatever you used) out of the loop and see if the amp returns to normal. There could be any number of variables that we aren't thinking about if you're using cables, which is why I like the 1/4" plug solution. It's small and won't interact with any other stuff around the back of the amp.

Anyway, with some more info, I'm sure we can troubleshoot your amp.

 

[hal9000]

Where is this jack? Part of the "external switching" jacks? And what would you be using as a switch?

Yeah, the FX Loop switching jack is on the back of the amp and takes a 1/4" instrument cable. You can use any latching switch you have lying around.

If you would also like to check out this mod so we can get some empirical data, that would be nice. I can step you through the process if necessary.

Again, there should be no way to damage the amp provided my instructions are followed carefully. The FX Send Strength knob does exactly the same thing that the FX MIX pot does when grounded, so there's no chance of damaging the preamp. If you go here, you can see what I'm talking about: http://www.tubefreak.com/tremvrb3.gif

 

[jbird]

Yeah, the FX Loop switching jack is on the back of the amp and takes a 1/4" instrument cable. You can use any latching switch you have lying around.

But the FX Loop switching jack is part of the external switching jacks, no? From the manual: "These jacks allow (usually MIDI-programmed) operation of your amps functions from an external switching source. In either case, the switching is accomplished by connecting ("shorting") the jack's "tip" to it's "ring" (or ground)" Am I missing something here? Mods to a cable inserted in the send and return jacks? Then using the external switches? Is the latching device part of the ("usually" midi programmed)? I'm at a loss here, and someone's amp is not working! Please clarify!

 

[hal9000]

Yeah, the FX Loop switching jack is on the back of the amp and takes a 1/4" instrument cable. You can use any latching switch you have lying around.

But the FX Loop switching jack is part of the external switching jacks, no? From the manual: "These jacks allow (usually MIDI-programmed) operation of your amps functions from an external switching source. In either case, the switching is accomplished by connecting ("shorting") the jack's "tip" to it's "ring" (or ground)" Am I missing something here? Mods to a cable inserted in the send and return jacks? Then using the external switches? Is the latching device part of the ("usually" midi programmed)? I'm at a loss here, and someone's amp is not working! Please clarify!

The FX MIX Pot master mod and FX switching jacks are totally separate.

Look at the schematic I posted. All the FX loop switching jack does is send a signal to the amp that the FX loop is to be taken out of the circuit. The jack simply needs the sleeve to be shorted to the tip, which is what a latching footswitch does. A lot of the time MIDI processors have relays that can be programmed to close/open based on the patch. I use my G-Major to change channels on my Mesa F-100 by using its relays to short the pins for CH1/CH2 and Contour. It works great.

Look at my mod diagram:

All you're doing is grounding the bottom leg of the FX MIX pot which will act as a second master volume when switching into the circuit via the FX loop switching jack. Again, the mod does exactly the same thing as the FX SEND pot, so there is no danger in a properly executed mod. Since I can't guarantee that people will do the mod exactly as I say, nor can I predict failing tubes, you have to do this procedure at your own risk. Now, there have been many people who've successfully performed this mod with their F-series amp, but a few have had problems because they didn't follow the directions. Nothing bad happened though, but the mod didn't work. The fact is, if it's done right at all, it will work as a second master. Any other behavior is a deviation from the plan.

 

[canon]

I soldered the pin to ground within a right angle jack, it could have been intermittent I suppose (i'm at work now so can't check). Does that give a clue to the problem? I'm guessing it's at least a fried resistor or cap or relay? Anyway, nothing I think I would tackle myself.

I did remove the jacks immediately and tried all the effects loop switching options, including always-bypass, and replacing all the preamp tubes, still had the problem.