Up for sale here is this set of 2 brand new Nippon Chemi-Con 24000 uf 100v capacitors. These are drop-in replacements for the two 3" main filter caps in the Bose 1800 and 1801 amps. They fit the old clamps perfectly! These are not for replacing the smaller cap that goes in-between the two big caps.
These are the same capacitors I use when I am rebuilding vintage gear. They go up a bit in capacitance and voltage compared to the old caps, but they are great subs and work perfectly in the 1800/1801. These measure 76.8mm (3") in diameter and 106mm (4.18") tall, and use screw terminals. The screws are included. These are authentic Made in USA capacitors, and were made in 2021 or 2022.
Please note that the screws on these may be thicker than the screws on the old main caps, so you may need to enlarge the terminals on the amp in order to accommodate this. You can drill out the old ring terminals and center mounting piece with a 5mm drill bit if you want, or just replace the old ring terminals, or cut the ring terminals open to make them into spade terminals. Please see my pictures for details.
A note about installation:
Main filter capacitors are usually used to provide the positive and negative rails to the amplifier section, so one of them will appear to be wired backwards (with positive to chassis ground). This is normal. Before you replace your capacitors, take some clear pictures of the wiring so you will know how to connect the new ones. If your equipment starts blowing fuses after replacing the main filter capacitors, you probably wired one backwards.
US shipping and handling is $15, and international is $40. If you have any questions, please ask.
I have more capacitors and lots of vintage electronics listed--feel free to take a look!