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Converting Sub Woofer amp to guitar amp? Answered

I have a powered sub-woofer that had a blown speaker and being that I spent the money to get a better one I thought that converting the old sub woofer amp to use for my guitar would be a good idea. I already have something to practice with but making something that can be used for gigs would be great. However, I'm not an avid or experienced electronic wizard and will need the help to complete this project.
Here is the info I have on the amp itself;

OUTPUT POWER                          50W (4 ohms,DIN)
THD                                                  10% @ 55Hz
Reproduction Freq. Response   45Hz - 150Hz
Phase Switch                                  0, 180 degrees
Input Sensitivity (Sub In)                460 mVrms
AC Power                                         120V/60Hz           
Power Consumption                     70W (at 1/8 rated power)
Standby Power Consumption     <6W

What I do know that I need is a 1/4" mono plug jack and being that the input for the woofer is mono putting that in shouldn't be a problem. I'm mostly concerned about the frequencies that the amp will handle for playing a guitar and speaker recommendations. Plus any other opinions will be appreciated.
I am expecting this to be a clean sounding amp and as it sits will only provide volume. An EQ is planned to be used after this amp is put together and then eventually an overdrive. I'm planning on connecting 2 50W speakers and wondering if I should hook them up in serial or parallel. With the help of my fellow instructabl-ians I will be able to post my 1st submission.


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9 years ago

So tell me if I'm understanding you correctly:
You are trying to take the amp from a powered stand-alone sub woofer and use it for a guitar amp?

If it was a stand-alone woofer, then you would have to assume that the cross-over is built right into the amp. (Assuming you didn't have a cross-over in your system... which would probably not be the case unless you had a REALLY REALLY REALLY nice system like a professional audio system.)

If this is the case, then unless you can bypass the cross-over, you will only have low end. You will not get nice clear sound with just low end.