Volume boost and drive in the fx loop - dangerous?

[MayTheFuzzBeWithYou]

Hey mods, feel free to put this in the tech or in the amp section if it's if better use there!

Hey folks!

Some time ago I read in either a guitar magazine or an online format like tonereport or on premierguitar or a similar site that one should never put volume alterating (boosting) devices in the fx loop of an amp as it puts extra stress on the power tubes and so can drastically lower their lifespan or do even worse things.

Have you heard about this? Read it somewhere too? If so, do you still have a source for it?

The only thing I found yesterday was an entry by deathrollJM on the esp forum from some years ago...with no sources but his knowledge of amp building? Is/was he a user here?

It makes sense to me. But I would like to have somewhat of proof. Not that I use the fx loop of my supersonic (only amp I got with fx loop) regulary... but if I do, only to put either the roland 201 space echo there or to patch it and use the send and return volume knobs to make it a badass boost.

But hypothetically speaking, what if I use my Acuapulco Gold or a Fuzz war with tons of volume reserves in there?

[oid]

That is myth, complete and absolute malarkey.

In the average tube amp we we have 12AX7s in the preamp, these can output ~60 volts of clean audio, a bit more with distortion, a pedal can output maybe 8 volts, 17 on an 18 volt pedal, far less than the tubes manage on their own. Pedals do not hit the tubes anywhere as hard as the tubes themselves do, it is how we get out distorted tones and the tubes do not care if it is a pedal or a tube driving them.

[Shadoweclipse13]

I'd never heard that myth. Glad to know it isn't true. I read from Bjorn Riis that he puts a clean boost in the effects loop of certain amps of his to give more clean headroom, and always thought that was a neat trick.

[MayTheFuzzBeWithYou]

Okay, than I've fallen for that hoax/myth... was surely more than a year ago. But it somehow burned itself into my brain.
And in most fx loop tutorials they say to put delays, reverbs and maybe modulation there...never a mention of boost or drive... so these two statements together made even more sense...

But as I said I never really used the fx-loop except for the space echo - 'cause I didn't have a proper footswitch for it but the supersonic comes with one that can activate/deactivate the loop...and it makes it really usable (less noisy)!
The only volume altering thing there was the ehx silencer passive attenuator once... but this only sucks volume...doesn't add any.
Anyhow... thanks for clearing these mists for me. I may even give it a try once!

[oid]

a clean boost in the effects loop of certain amps of his to give more clean headroom, and always thought that was a neat trick.

That is a fine example of how such rumors get started, a simple statement by Mr. Riis that is perfectly true but easy for many to misconstrue. It tells us two things about those certain amps, they have fairly clean preamps which hit the power amp hard and that they either lack a master volume or have a master that has a negative impact on tone in the desired range. He is actually using the boost to cut gain here, as a sort of active master volume, this allows for more fiddle room with the preamps volume and tone controls before the power amp distorts and can keep the power amp from ever distorting. Any clean pedal with a volume control can be used in this fashion, clean boosts are just well suited if your goal is to get more clean without color, volume pedals are sometimes used here as well, puts the master volume at ones foot.

This trick can be very useful since it can allow you to keep the preamps volume, and the master, fairly high where it does not stomp all over the treble response while maintaining a clean sound. For many all this is obvious, the boost is used to cut volume not increase it, but there is always that group which takes such statements at face value, especially if one of their idols said it. Not suggesting you did or did not grasp this from Mr. RIis' statement, I just read such things and have flashbacks to my life in the repair business. Most likely some amp tech somewhere has gotten a visit from someone with a 'broken' amp which gets more distorted with a cranked clean boost in its FX loop and had to have that fun talk explaining to the amps owner how their idol is not perfect and infallible. An odd little corner the guitar and amp tech occasionally gets backed into that if answered carefully and with tact will get you a client for years to come.

The rock guitarist is not the most concise of creatures.

[Shadoweclipse13]

That's interesting. Hadn't thought of it that way.

I wonder how hitting the power amp with a treble booster would sound...

[oid]

That's interesting. Hadn't thought of it that way.

I wonder how hitting the power amp with a treble booster would sound...

Brighter.

[Shadoweclipse13]

[jorri]

Its useful if you only use one channel. Since distortion is after EQ then the tonal range of the distortion would overtake the sound of the preamp. But i have no idea of whether is would creat undesirable fizz. I used to do it with an EQ pedal that could change sound so much that way i called it the amp sim button.