guitar amp ->PA =cabulator

[tedmich]

so I have an increasing number of amp heads around but no std guitar cabs, but I do have a couple old PA cabs with 15s and compression horns which I wouldn't mind using with the amps. The problem is the compression horn since you do not want to hear a 5150 through a tweeter EVER. But the 15 cannot produce the 2-5k peak that people expect from their typical guitar speaker so you need a little high freq extension.

typical guitar speaker behavior is as follows:
V30: drops off at about 30 db/octave starting at about 4 kHz, with a 5 db bump at 2 kHz
new Emmie CV-75 (V30 clone): drops off at about 22 db/octave starting at about 4 kHz, with a 5 db bump at 1.8 kHz
G10: drops off at about 15 db/octave starting at about 3 kHz, with a 5 db bump at 2 kHz
Emmie Manowar: drops off at about 15 db/octave starting at about 3.2 kHz, with a 9 db bump at 2kHz

A solution I am trying is the cabulator, a simple 2nd order crossover that gives me the ~12db/octave drop off, and I'm using a Butterworth filter to give a little of the bump at the crossover freq. Std cap values made the following filter the easiest to make:

8 ohms in and out
4.4uF parallel cap (2.2uF x2 at 350VDC)
0.56mH air core inductor 18AWG
crossover freq. 3200Hz

we'll see how it sounds!

[teemuk]

Interesting idea.

I wonder though if the load impedance, due to crossover, will differ largely from that presented by a single typical loudspeaker. You probably are well aware of that many guitar amps have low damping factors and that response is sort of a "equalizer" itself.

But as said, interesting idea. Looking forward to reading and hearing results.