What is the jack nut thread size for Peavey PR15

but you would have to go to Peavey direct for service info.

Please see my previous answer.

When you unload one amplifier you stand the chance of killing the amp's output transistor. If you must use only one speaker, you have to bridge the amps.

diaphram or crossover..

Actually its pretty funny thing with those speakers is the "fuse" is Actually called a Lamp in this case. These are what they call a " Red Dot Fuse ". in all the years i've been doing this i've never thought to look up the value haha. Just have to know there are Red Dot lamps and Blue dots and No Dot. If you examine the LAMP you should see somewhere close to the ends ON THE GLASS a color dot of some kind. almost like someone painted it on there. Red Dot Lamp. any parts distributer for people like Harbinger, Peavey, and B52 will KNOW what your talking about

The consense is that the yellow is positive... However, if these come from a 1/4 inch jack, the color that connects to the TIP of the jack is the positive one..

i) I believe you can access the fuse by removing the Input Jack Panel.

ii) If fuse is OK, then unscrew the horn unit, take off one speaker wire & measure resistance. If it is open circuit then you can order a replacement horn diaphragm (if you feel confident to fit it to the horn).

Yes it unscrews. Use a oil filter wrench it will make things easier

Here is a site that has PR15 fuses... shown as a 2.1 amp. Very strange value, and it must strictly be for the tweeter portion as 2.1 amps is nothing for a speaker... I don't know that I believe this site.

If you have a Guitar Center near you, inquire there.

Check for impedance ( resistance) in ohms on the speakers disconnected from the circuit using a volt/ohm meter. I think the woofers are 8 ohms and the tweeters are 8 ohms. Also check for bad solder joints where the jacks are soldered to the circuit boards.