Re: Fender amps - bad sounds when the voltage drops (question for the technicians)

In article <1192852165.733558.261440@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
<GrovesAustin@xxxxxxxxx> wrote:
I just got in from an outdoor gig, and I'm hoping somebody here can
explain a technical problem we had. During loud sections, my guitar
amp(s) experienced some really unpleasant, flabby, low frequency
distortion. Since it happened primarily when I hit a power chord, or
when I kicked in my boost pedal, and more so after it got dark and the
lights were on, I surmise that it was related to momentarily sagging
line voltage. Oh, and the power was coming through 100ft extension
cords.

I was using my primo rig that is reserved for good (and close-to-home)
gigs - a vintage blackface deluxe reverb and a vintage blackface
vibrolux reverb in parallel - volume at 4, miked through a large PA.
The vibrolux was the worst, and I replaced it with my early eighties
fender Concert amp for the second set. I eventually took the Deluxe
out of the mix too, and just used the Concert. Even then, I
occasionally heard the flabby distortion, but not as bad.

This is the second time this has happened, and ironically the first
was at the same venue a year ago...but that time we were running from
a large generator, and after dark when the generator was also powering
big lights, we had this problem. Today, were running on power company
power, meaning the power situation was completely different.

So...the PA equipment did not seem to be affected (Crown and QSC amps,
Allen & Heath mixer, etc). I may have heard it in the bass amp, but
I'm not certain (70s Acoustic solid state head). But the guitar amps
were sounding terrible when the problem occurred (all three of them,
but to varying degrees).

My tech questions are:
* does it make sense that the problem was caused by sagging line
voltage, or is there another explanation to consider?

Yep. Not enough ( or too many ) volts can cause all sorts of weirdness

* does it make sense that my fender tube amps would be the weakest
link on the stage in terms of handling sagging line voltage?
* Is there a way to make these amps handle sagging line voltage
better, or alternatively, are there (toneful) guitar amps that would
tolerate this situation better?
* Is there a practical way to regulate the line voltage in a gig
situation?

Check out something like this

<http://musical-instruments.pricegrabber.com/power-conditioners/m/3837610/>



By way of clarification: the distortion that I experienced was sort-of
a combination of low-frequency breakup with possibly a 60hz or other
low frequency buzz. It was clearly triggered by loud passages, but
when it wasn't happening everything was very sweet and toneful.

Thanks for any help or ideas,
John



.

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