Dumble style effects loops

TeleTex82

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Hey y'all, I have a VHT D50, a Dumble clone, that I love. It is my understanding that this has a Dumble style effects loop as well. This is something I'm not sure I understand. I have been waiting to get either one of the new TC Electronics Plethora's or the Line 6 PodGo's for modulation effects. Would this kind of thing work with a Dumble style effects loop or do I need to get something like a Dumbleator? Thanks in advance.
 

FenderLover

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The FX loop is passive, and not a strong point of many amps that uses it. The preamp level tends to be too high, and while the input of the loop effect can be reduced to accommodate, the output level of the loop effect does not have the juice to drive the power amp to the same level as if there were nothing plugged in. Depending how much volume you need it may not be an issue at all. It's one reason why playing a 50-100W amp with this kind of loop is not a problem if you only turn the output up to 2 or 3.

If you need to turn down the level to your FX but have to turn the master up to 8 or 9 it might still be OK. But if 8 or 9 doesn't give you the volume you need it's because the output of the loop effect isn't hitting the output stage very hard.

That's what an external active FX loop like the Dumbleator will do if you need full power with best flexibility using a variety of gear in the loop. It will attenuate as much as needed, then jack up the output to drive the power stage as hard as you want.

Do you need an external active loop, or do you just want one? Not judging, just curious.
 

TeleTex82

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The FX loop is passive, and not a strong point of many amps that uses it. The preamp level tends to be too high, and while the input of the loop effect can be reduced to accommodate, the output level of the loop effect does not have the juice to drive the power amp to the same level as if there were nothing plugged in. Depending how much volume you need it may not be an issue at all. It's one reason why playing a 50-100W amp with this kind of loop is not a problem if you only turn the output up to 2 or 3.

If you need to turn down the level to your FX but have to turn the master up to 8 or 9 it might still be OK. But if 8 or 9 doesn't give you the volume you need it's because the output of the loop effect isn't hitting the output stage very hard.

That's what an external active FX loop like the Dumbleator will do if you need full power with best flexibility using a variety of gear in the loop. It will attenuate as much as needed, then jack up the output to drive the power stage as hard as you want.

Do you need an external active loop, or do you just want one? Not judging, just curious.


Well, neither or both lol? I was just looking to get a multi effects pedal since I'm needing more modulation effects these days and I really liked what I heard from Line 6 and TC Electronics. Usually I just run a Reverb pedal so the loop has never been an issue. Just wanted to know if I were to get one of those floor units if it would sound like crap with the D50. Right now, volume is not a factor as we aren't rehearsing or playing out, but when we do I usually run 50 watts around noon or a little over and ride the guitar volume, that's for our bigger gigs though.

Thanks for the advice btw.
 

Samr

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Well, neither or both lol? I was just looking to get a multi effects pedal since I'm needing more modulation effects these days and I really liked what I heard from Line 6 and TC Electronics. Usually I just run a Reverb pedal so the loop has never been an issue. Just wanted to know if I were to get one of those floor units if it would sound like crap with the D50. Right now, volume is not a factor as we aren't rehearsing or playing out, but when we do I usually run 50 watts around noon or a little over and ride the guitar volume, that's for our bigger gigs though.

Thanks for the advice btw.
 

Samr

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Well, neither or both lol? I was just looking to get a multi effects pedal since I'm needing more modulation effects these days and I really liked what I heard from Line 6 and TC Electronics. Usually I just run a Reverb pedal so the loop has never been an issue. Just wanted to know if I were to get one of those floor units if it would sound like crap with the D50. Right now, volume is not a factor as we aren't rehearsing or playing out, but when we do I usually run 50 watts around noon or a little over and ride the guitar volume, that's for our bigger gigs though.

Thanks for the advice btw.
The problem with running effects in the loop on the D50 is that the loop send isn't buffered. You'll lose high end due to the capacitance of your effects chain and cables that are in the loop. Thats what the Dumbleator does, in addition to offering level adjustments. It makes it so that you have a loop that's buffered on both ends. You don't necessarily need a Dumbleator for that. For instance, you could just buy a good buffer pedal and set it on your amp with a 6" patch from the send, then run the cable from the output of the buffer pedal, going to the input of your pedal board effects that will be in the loop. It wouldn't be a tube buffered loop, as the Dumbleator provides, but it should regulate your signal impedance enough to keep you from getting the high end roll off that you would otherwise. It would also be hundreds cheaper.
 

Mowgli

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Agree with nearly everything above.

Fuchs makes the Verbrator (an affordable Dumbleator) for such "passive" effects loops. It is a "cathode follower" tube-based buffer that can run effects in either Series or Parallel. Plus it has an incredibly nice sounding digital reverb which I prefer to many if not most spring reverbs!

I've put passive effects loops in several of my amps and employ the Verbrator as both a Dumbleator-type buffer and a reverb unit. I run Verbrator in parallel mode with a dig. delay, chorus and EQ pedal. I think it is outstanding and would be a great addition to any passive effects loop.I wish they had a stereo rack mount version for my '80's rack.

That's my 2 cents!
 




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