Hello! I am trying to modify my cheap but cool B-40 Vision bass amplifier. It rolls off a lot of treble somewhere, but I can't figure out where.
I've already upgraded it with an Eminence Alpha 8 A and it's a powerful little combo that I like to use for practice.
I tried to trace the circuit but it's a nightmare getting all the connections right, and although the manufacturer provided me a schematic when I asked, it's a newer version. Apparanetly the factory of the original version that I posess burned down and the schematic can't be retrieved
So now I've got this mess here that I extracted and it should be mostly correct. There are still some parts missing. Input is on the left. I think I've got the most important parts but due to my so far limited experience with active tone controls, I can't figure out what's going on here. I have only ever built and analyzed tube amps and passive tone stacks on a very low level.
Can someone be so kind and help me out what components determine the treble and mid frequencies in this circuit? I would like to shift and narrow the mid frequency, and also increase the treble response and widen the frequency of the treble control. I realized I'm a bit lost currently.
I do understand that the treble and bass controls are in the negative feedback loop of U2a and I think C14, C15 should be responsible for the range of the treble control (wild guess). The bass response is probably determined by C12 and C13? I'm in over my head lol...
Any help is appreciated, and sorry for the maybe somewhat confusing arrangement. It's really much harder than I thought to trace this.
I've already upgraded it with an Eminence Alpha 8 A and it's a powerful little combo that I like to use for practice.
I tried to trace the circuit but it's a nightmare getting all the connections right, and although the manufacturer provided me a schematic when I asked, it's a newer version. Apparanetly the factory of the original version that I posess burned down and the schematic can't be retrieved
So now I've got this mess here that I extracted and it should be mostly correct. There are still some parts missing. Input is on the left. I think I've got the most important parts but due to my so far limited experience with active tone controls, I can't figure out what's going on here. I have only ever built and analyzed tube amps and passive tone stacks on a very low level.
Can someone be so kind and help me out what components determine the treble and mid frequencies in this circuit? I would like to shift and narrow the mid frequency, and also increase the treble response and widen the frequency of the treble control. I realized I'm a bit lost currently.
I do understand that the treble and bass controls are in the negative feedback loop of U2a and I think C14, C15 should be responsible for the range of the treble control (wild guess). The bass response is probably determined by C12 and C13? I'm in over my head lol...
Any help is appreciated, and sorry for the maybe somewhat confusing arrangement. It's really much harder than I thought to trace this.
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