So I have an original Fishman Loudbox from 2003. Really nice amp. I want to use it not just for guitar but also as a mono speaker. The frequency response is 100Hz - 20kHz ±4dB. The unit is a triamped design and there is a crossover somewhere on the board before it goes to these amps. I attached the schematics. I know its a lot of surface mount components, but I can solder and desolder them. I want to bring the response down to 20Hz if possible, that way it can go from 20Hz-20KHz like a regular amp can. Also the woofer is a 2Ω impediance. Very low compared to traditional speakers. The specs claim that it can pump 160W into a 2Ω load. The main voltage rails seem to be -33V and +33V. I find it hard to swallow that only one pair of outputs for the woofer can deliver 160W. The outputs are 2SD1842 and 2SB1232. Although to be fair, they are rated at 40A and 100V, so I assume these outputs are very rugged.
The tweeters are driven by a LM3886, and the midrange driver has it's own LM3886 output IC. Filter caps are 10,000mfd for the record.
The tweeters are driven by a LM3886, and the midrange driver has it's own LM3886 output IC. Filter caps are 10,000mfd for the record.