This thought has originated after I uncovered an old pair of speakers: Aiwa SX-E12 AFBS (Acoustic Feedback System). Some may remember these and the system they came with and others are probably scratching their heads/Googling.
To make it short, the speakers have two microphones placed in front of each of the drivers. The mics were powered by the amp, SX-120 or GX-120, which would control then control the movement of the speakers.
Any ways, I have the schematics for the amps in question and I can isolate the AFBS part of it. It's fairly simple really, it uses an old Mitsubishi M5218L DUal Op-Amp, a handful of resistors, and capacitors. Here is the schematic:
The original block diagram of the amp. What is cut out is the spectrum analyzer and some basic stuff like speaker set selection.
The project would be to make two chip amps, one for each speaker. Maybe LM4886 to "bi-chip" each speaker. Has anyone attempted this? Also, any pitfalls I should have in mind while I read up on pre-amp stages and what not.
To make it short, the speakers have two microphones placed in front of each of the drivers. The mics were powered by the amp, SX-120 or GX-120, which would control then control the movement of the speakers.
Any ways, I have the schematics for the amps in question and I can isolate the AFBS part of it. It's fairly simple really, it uses an old Mitsubishi M5218L DUal Op-Amp, a handful of resistors, and capacitors. Here is the schematic:
An externally hosted image should be here but it was not working when we last tested it.
The original block diagram of the amp. What is cut out is the spectrum analyzer and some basic stuff like speaker set selection.
An externally hosted image should be here but it was not working when we last tested it.
The project would be to make two chip amps, one for each speaker. Maybe LM4886 to "bi-chip" each speaker. Has anyone attempted this? Also, any pitfalls I should have in mind while I read up on pre-amp stages and what not.
I don't know if what you describe is anything like the Resurrectored GC but it could be.
Building a Gainclone chip amp using a Resurrector
Building a Gainclone chip amp using a Resurrector
Hrmm... It'd be interesting to know what is actually in it. But, the AFBS circuit actually uses microphones in front of the drivers. The mic feeds into the filter circuitry and the original, AIWA amp, would monitor the mic inputs and would prevent unnecessary cone movement.
I'll buy the parts and see how it works.
I'll buy the parts and see how it works.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.