| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 553.1 | Unity Gain is where it's at !!! | ANGORA::JACQUES | | Fri Mar 25 1988 15:43 | 40 |
|
The key is unity gain. If you are chaining effects together, they
should all be set for unity gain. If you set each effect to add a
little bit of gain, you have to be careful to only use one at a time.
If you are going to layer them, then you should set all of them for
unity, except maybe the last effect in the chain can be boosted
a little to cut above the other instruments for playing leads.
Floor stomp effects usually do not have LED level indicators to
tell you if you are boosting, cutting, or at unity gain. You have
to experiment with them. You might want to make a mark on the pedal
with a china marker to indicate where you get unity gain. It helps
you to get repeatable results.
As far as whether it can hurt amplifier inputs, I am sure that it
must cause excessive wear on an amp if you are always overdiving
the input stage. In a transistor amp, you are going into an op amp
which has a rather large feedback resistor connecting the output
to the input. This tends to protect the op amp from seeing too much
signal. In a tube amp, it is a different story. You may wear out
preamp tubes faster, if you are overdriving them, but at least they
can be easily replaced.
I would also be concerned about whether the input signal is clipping
before it gets to the amp. If it is, then you are injecting DC into
the amps input stage. Not Kosher !!! This is possible when one
effect box overdrives the next one in line. I used to have a Boss
CE1 (a real antique, probably the first chorus device ever) which
was level sensitive. You could not get unity out of it no matter
what you did. Therefore, you tended to load down the guitar signal,
and sent a watered-down signal to the amp. The new Boss chorus units
do not have this problem at all.
Effects are sometimes tricky to use effectively, but they are worth
it. Without them, we might all get board and trade in our guitars
for golf clubs.
Mark Jacques
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| 553.2 | I Wouldn't Worry Too Much | AQUA::ROST | Bimbo, Limbo, Spam | Fri Mar 25 1988 16:33 | 10 |
|
Remember, a stomp box running on a nine-volt battery cannot give
a signal greater than 4.5 volts (AC), so it's not as drastic a problem
as you might think.
I have yet to hear of any such problems at the *input*. At the
output, though if you're crankin' the s**t out of the amp due to
a high input signal you might have some problems.
|
| 553.3 | I wouldn't worry either | BARTLS::MOLLER | Vegetation: A way of life | Fri Mar 25 1988 17:23 | 13 |
| I (an EE) don't think that you will hurt the input stage in any
way with too large of a signal (All that happens is that the the
signal is clipped). I love the old tube amplifiers because of the
output transformer. You can force the Tranformer to accept too much
signal, and cause the core (magnetic portion) to saturate. This,
among other things, gives the tube amp a unique sound. Too much
input signal will cause clipping somewhere in any amplifier. If,
however, you were to increase voltages in the amplifier, you might
be in for a nasty surprize (this was done on old Fender Amps to
get a Marshall sound - hard as hell on the tubes, as well as causing
everything to run too hot).
Jens
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| 553.4 | Overloaded that sucker | SRFSUP::MORRIS | The best laid plans never get laid | Mon Jun 27 1988 14:29 | 16 |
| In my endless search for the ultimate distortion, I fried my Peavey
backstage 30.
I plugged my strat into a barcus-berry 6 channel mixer (it is kind
of a resistance mixer, it takes 2 9 volts to run), and cranked my
volume knob, the mixer input knob, the mixer output knob, the amp
preamp knob, and had the master volume knob on 0. As in full
counter-clockwise. Well this was okay for a while, but then I
unplugged the cords and turned off the amp. I heard a whistle come
out of the amp, and thought...oh great, I did it now.
The preamp seems to work fine (at least the preamp out jack gives
me a good signal), so I think it's the power amp I'm having problems
with. Does anyone know where I can begin with the old multimeter?
Thanx, Ashley
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