channel switching with VM

[HappyBlues]

I like VM. I love it's overdrive. I love all quantities of gain VM is capable of. But I really need channel switching and even some effects switching capabilities. Like switching in the same moment from OD to clean and turning delay on.

I currently use Boss GT-8 which acts as some kind of channel switcher. I either run input of VM hot and back off volume after preamp, or hit VM's preamp not so hot (to get clean, or breakup tones) and then raise volume so Dirty and Clean are same volume.

Anyone knows of any other way doing this?

I thought of tc electronic Nova System, but then, that won't be VM's drive, just some analog pedal drive.

[Ex-Mesa]

Vaguely related. Looking at this month's Guitar World mag, it shows Neil Young's "Wiggler" gizmo that hooks on the amp face and turns the knobs automatically to various presets. That would be a cool solution to the one-channel limitation. Build that, and it will sell!

[HappyBlues]

you could also have motorized knobs... but boy, I am no investment banker...

[MKB]

Vaguely related. Looking at this month's Guitar World mag, it shows Neil Young's "Wiggler" gizmo that hooks on the amp face and turns the knobs automatically to various presets. That would be a cool solution to the one-channel limitation. Build that, and it will sell!

That would indeed be a very cool mod for the VM, but would be a complete pain to implement. You'd have to hang a large box with the motors off the front of the VM. You could replace the pots in the VM with motorized ones, but they might be hard to get in the values needed for the VM. Other than those issues, it'd be a terrific idea.

It would actually go a long way if you could motorize only a few of the knobs, mainly Detail and Body and the master volume. For fun add control of LDR and HDR. Now that would ROCK.

I don't recall anybody making an aftermarket device that would be adaptable to this, but it would be a mighty fun DIY project if your microcontroller chops are up to snuff. I'd give it a shot if I had anywhere near the time.

[Ex-Mesa]

I'm thinking model airplane technology. Remote controls! Flaps out.

[Jeando]

I like VM. I love it's overdrive. I love all quantities of gain VM is capable of. But I really need channel switching and even some effects switching capabilities. Like switching in the same moment from OD to clean and turning delay on.

I currently use Boss GT-8 which acts as some kind of channel switcher. I either run input of VM hot and back off volume after preamp, or hit VM's preamp not so hot (to get clean, or breakup tones) and then raise volume so Dirty and Clean are same volume.

Anyone knows of any other way doing this?

I thought of tc electronic Nova System, but then, that won't be VM's drive, just some analog pedal drive.

Hello, check my VM and GT-8 setup in the "Volume Boost Option" topic. Any questions or new ideas are welcome.

[SteveD]

Welcome to the forum Jeando.

[Jeando]

Welcome to the forum Jeando.

Thanks Steve, i´m very happy to share my marshall experience with the very experts and learn something.

[Murfdog]

You can dial back the Body and Detail to about 12:00 on the high dynamic range, and get a cleaner sound on the low dynamic range. Unless you need Pantera type overdrive, it works pretty well. But, if you really need channel switching you should look into another model; such as the JVM or DSL.

[ClubAndCountry]

But those amps sound very different.

The problem is for someone that prefers the tone of a Vintage Modern but wants to be able to switch between the High and Low ranges for cleaner and more overdriven sounds, and needs to be able to control the volume jump. That can only be done by either modifying the amp to make the master volume switchable (or adding a second master for the High mode), or by using another sort of master volume in the effects loop - which is what I think freesun is doing.

Since the High/Low switch on the amp's footswitch is a momentary type, and so is the switch in a Boss pedal, you could do this: run a Boss GE-7 pedal in the loop, and modify it with an external switch jack. Then open up the Vintage Modern footswitch and you should find (assuming it uses the same parts as many other Marshall footswitches) that the High/Low switch is a DPDT with only one side used. If so, add a jack to the pedal, connected to the unused side of the switch. Now, if you connect the new jack on the footswitch to the external switching jack on the GE-7, you should be able to change modes on the amp and switch on the GE-7 with the same button. Set the GE-7 to cut the volume - and alter the EQ if you want - and you now have a (nearly) channel-switchable Vintage Modern! You are still limited by having the same gain controls for both 'channels', but it should at least be possible to get a good compromise without the volume jump.

[MKB]

The thing that makes channel switching on the VM so tough is the type of master volume used, which is in the circuit after the phase inverter. It is a dual section pot, which means perhaps two pot sections will need to be selected to change the volume level. Also, a significant amount of the preamp overdrive is generated by the phase inverter tube, which means it is difficult to control this volume level through the effects loop.

I believe that if a modification is made to implement a second PPI master volume, and this is switched at the same time as the LDR/HDR switch, the VM would effectively become a two channel amp and still maintain the essence of what makes it great.

There would be several ways of implementing this second master, and the circuitry exists to control the necessary relay to a point, but some work would need to be done to implement this properly. Switching circuit levels like this within the power amp feedback loop might cause popping or other issues. But it is possible. And there is the pesky problem of adding another pot to the amp without drilling another hole in the chassis.

I've had good luck setting up the VM so it just begins to break up with a clean boost in LDR, then using LDR and HDR with the boost on and off gives four different tones and gain levels. This works almost as well as a multi-channel amp, but still will not give loud cleans.