i just bought a mixer to use for my band, and i was wondering if i can use the guitar amps my band has as PA speakers. i dont really want to spend the money to buy PA speakers and a power amplifier until we play our first show, sometime in June. will it be ok to use the output of the mixer into the guitar amps, for practice until then.
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You probably could yes, mightn't help the amps health, but it should be alright.

Bass/Keyboard amps would be muchos better.
I'm sure the sound has already answered the question. Guitar amps tend to be eq spiked to prejudice the midrange and PA's tend to give a more flat, even eq response. Hopefully if your mixer has an unpowered line out and an eq to pull the midrange way down, you may be able to get intelligible sound.
Bass amps as speakers FTW.....
I've bought, sold, and traded more gear than I care to admit.
The keyboard amp is made to have a larger range of frequencies. Which would be great for a PA speaker. Just set the EQ flat.
I like the llamaking's response better, a bass or keyboard amp that has flat response -better!
Quote by thellamaking
Bass/Keyboard amps would be muchos better.

Acoustic guitar amps are made for this, most have a microphone input.
Couldn't you take a line out of the mixer and into the effects return of the amp, effectively bypassing the preamp of the amplifier and straight into the power amp?
You also want to consider the speaker in the amp itself. Guitar amp speakers are not produced to provide a flat frequency response... the speaker itself is biased to toward some frequency ranges (and every guitar speaker is different). This entirely 'aside' from the amp's own biasing.

You can certainly do it (using the amp). It should work. But you will not get the "best" or "most accurate" sound from it. But it is certainly something you can do to resolve your situation.

You will want an actual PA speaker (or as noted, keyboard/etc) when you actually purchase the speaker you will be using for this.
Use the monitor mix coming from your mixer you will have no problems. I use a fender bassman for one of our guitar players monitor.
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