amplifier going super sonic, help!

[The Fight]

Hey guys!
As some of you know I bought a Friedman modified Marshall super lead plexi for a lead channel that I pair with a Splawn quickrod 100 watt. Both amps are ran separate and toggled in and out using a tc electronics g system and a head switcher.

I set everything up correctly and all seems to be working just fine except for when I'm running the plexi. I get this crazy tubular sound that get wound up and picks up momentum and then goes super sonic.
I have a feeling it has something to do with the fx loop and definitely starts when the gain is up 12:00. The effects loop on both amps is controlled with the g system as well via midi with a midi looper. I have no such problems with my splawn amp and actually has been very good to me lately.
I tryed running a noise gate at the front and the back of the amp but doesn't seem to help. I went as far as buying a rocktron hush and noise suppression system and still no change. It almost feels like the problem is tide in with the effects loop of the amplifier. Like I said the hush system didn't work well enough to use, it almost cuts out all usable tone and just sound to thin. Tried to dial it in but no use.

Anyone ever have this problem, help would be greatly appreciated.

 

[aristotle]

I'm assuming that when you run the Plexi standalone you're not getting the problem?

Which head switcher are you using? My only experience is with the Headbone...but I assume that others must work the same way. They are designed such that you need to run the guitar signal through them so that they can mute the input before they do the head switch. This may or may not be associated with your problem, but with the headbone at least, you'll run into problems if you rely on a separate system to re-route your guitar signal.

Assuming that has nothing to do with your problem, I'd remove everything from the Plexi loop, remove the g system and see if you have troubles just running your guitar through the head switcher and through the plexi as a start. Then start adding to your configuration until you find the step that causes the problem.

 

[aristotle]

Oh...and I figure that you know this, but it's worth mentioning... If you are running any time based effects in your loops, you need to switch them off (or switch your loop off) well in advance of a head switch. Otherwise, the power section of the amp that you're switching from will be actively driving the head switcher for a period of time and the load isn't designed to handle that. Causes damage to both the amp and the switcher.

 

[The Fight]

Yes I am using the headbone and no I don't have the same problem when it's just bare bottom guitar to amp. And yes I'm using the head bone to re-route the guitar signal.

I think problem it's definitely tied in with the effects loop. But it's interesting bcs the system is connected exactly the same way with the other amp.
I read somewhere that some amps have touchy loops and seeing that this amp did not have an effect loop originally, mby could well be the problem. And I'm not sure what kind of effects loop it is exactly, meaning series or parallel, and not sure the difference.
I'll try to move backwards with the setup up when the sun comes up.

Thanks for the input!

 

[Boogie]

I'd remove everything from the Plexi loop, remove the g system and see if you have troubles just running your guitar through the head switcher and through the plexi as a start.

Agreed, I'd start regression testing. Start from the beginning and pin-down where the problem appears. Post up the results!

*edit*
Between my browser crashes, you guys already got there. Don't think I can contribute anything of substance. Aristotle has you covered.

 

[László]

When researching head switchers, I saw quite a few mentions of the howling thing happening with higher gain amps and the Headbone switchers. Someone said that Radial is aware of the problem and has some workarounds, if you contact their customer service. Evidently it doesn't happen with every amp model.

I don't know if this is true, but it was discussed in several places I chanced upon. It's one of the reasons I wasn't excited about trying one out.

Incidentally, the Ampete lets you switch heads and not have to switch off time based effects in the loop, and the loop works with all of the heads attached that have loops. They make a smaller version as well, a 2 heads + 2 cabs switcher, in addition to the 4x4.

 

[The Fight]

Yep you guys are totally right. Les it is the Radial that's giving me problems. Everything works fine up until I run the Radial. I'll be ordering the Ampete 222 tonight and hopefully it will solve all of my noise issues.
And about the Radial headbone, I feel they need to warn people about this problem. I didn't find nothing in the owners manual and had to do extensive searching just to find any sort of answers. I appreciate the help guys, I really do!

 

[László]

The Ampete looks like a good unit. I'd really be interested in hearing your reaction to it - please post a review!

 

[The Fight]

Oh yes sir I am but I'm using a loop midi controlled system to do that for me.

Hey guys I just ordered the Ampete 222 system just now and should be on its way from Germany.
I'm sure you guys are well aware of it but I'll just share a few things about it.
The Ampete 222 allows you to toggle between two heads and two cabs wile at the same time feeding your effects loop in to both amps. Well.. And cutting off signals.

I like that it does all that, bcs I had to buy all that stuff separate, including wire in between. Plus being it's all in one box could very well cut delay time when switching.
I'm still pretty pissed about the Radial thing.
I know Mark Tremonti uses/used it and he's all gain. Mby I'll ask him about it next time I see him

Thanks for the help gentlemen! And I'll report back when I get this new expensive toy!