How do I reduce the overall gain in my preamp ?

I owned an ARC LS-1 and also had to tame this monster!
Call Lenard (at the ARC factory) and tell him your problem.
He sent me a diagram of the solder traces (bottom of circuit board) and told me where to sever a trace to reduce overall gain (it worked, of course).

I would not try to modify your preamp.

I would look at getting a different preamp or look at getting a source that outputs less. Or look at getting speakers that are less sensative.

Just my 2c.

KF

KF, I believe you meant poweramp and not speakers.

If poweramp is sencitive and source component(s) with high output why not going for passive preamp and sell the line-stage?

Hi Albert
Dweller's suggestion is definitely the best of the above. If you aren't able to follow the mod instructions for lack of technical know-how, a local repair shop should do this for you fairly inexpensively. Retain the mod instructions for future reversal in case you decide to sell it later on.
Or insert a quality passive attenuator into the tape loop, as an aside on Newbee's suggestion.

Marakanetz, you can do it as you state with a less sensitive amp OR speakers. Going from 95db sensitive speakers to say 92db speakers will give your system less overall gain/volume.

KF