I have picked up a lovely pair of B&W 801 Series 80, built mid-1981. The cabinets and grills are in great condition.
They have some audible electrical issues, and I want to restore them to their original glory (no upgrades/mods, yet). Some general wisdom seems to be to bypass those attenuators, which I won't use anyway, and modernize the crossovers...but I just want them back to stock.
Each speaker has three circuit boards, one in the hf/mid housing with selectable attenuation, and two crossover modules in the bass enclosure.
Starting with the easiest to access (the upper housing), I verified that the "Flat" HF path is dead...both resistors on each speaker are dead, and they even look like it. The other resistors are roughly correct for their listed values, though they fluctuate a bit outside of tolerances. I'd think it might be best just to replace everything while I'm in there?
I don't know how to properly test the capacitors/inductors.
I have obtained the schematics, and the circuit boards are easy to access, with plenty of space between components. The circuits appear to be pretty simple.
I don't know much, but I can follow instructions.
A quick search for a specific resistor on mouser told me quickly that I don't know enough about what I'm doing.
Help?
Thank you.
-mitch
Attenuator Schematic and photo:
Upper PCB
Lower PCB
---
They have some audible electrical issues, and I want to restore them to their original glory (no upgrades/mods, yet). Some general wisdom seems to be to bypass those attenuators, which I won't use anyway, and modernize the crossovers...but I just want them back to stock.
Each speaker has three circuit boards, one in the hf/mid housing with selectable attenuation, and two crossover modules in the bass enclosure.
Starting with the easiest to access (the upper housing), I verified that the "Flat" HF path is dead...both resistors on each speaker are dead, and they even look like it. The other resistors are roughly correct for their listed values, though they fluctuate a bit outside of tolerances. I'd think it might be best just to replace everything while I'm in there?
I don't know how to properly test the capacitors/inductors.
I have obtained the schematics, and the circuit boards are easy to access, with plenty of space between components. The circuits appear to be pretty simple.
I don't know much, but I can follow instructions.
A quick search for a specific resistor on mouser told me quickly that I don't know enough about what I'm doing.
Help?
Thank you.
-mitch
Attenuator Schematic and photo:
Upper PCB
Lower PCB
---
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