3 Tonearms 1 preamp

Bob, to do what you want to do is a compromise, and you will have switches in the signal path before the RIAA EQ lifts the voltage of the signal, unless you use seperate phono preamps into seperate line level inputs in your preamp.

That said, if you choose to use swiching, keeping the wiring as short as possible, with the least amount of breaks, makes the most sense, and that generally calls for switching right at the input of the phono preamp. You still will have the switch contacts and the short lengths of wire, but at least you don't have the breaks and cable effects of additional interconnects and their added capacitance as well as the overall longer signal path.

I had a similar dilema, three tables and one phono section, a Fon Lo Thingee by Blue Circle. I liked it so much I had a custom Phono section made by Blue Circle that incorporated three Fon Lo Thingee Phono sections put into a "Proper Box" with a Grayhill three position selector switch going to one output. Each phono section has its own input with selectable gain and loading. The design utlized the existing Biggee power supply and SP capacitor pack to save a few dollars. I think it is really great and perfect solution for me.

that is why I use McIntosh C20.....

Thanks everyone.
With my budget I think that the idea of adding a selector switch and phono jacks at the preamp is the way to go. I will get the switch and jacks from an old receiver. No real estate on the pre so I'll make a box that rests on top and will enter thru the rca holes once the jacks are removed and hard wire direct. If I ever want to trade to another pre it will be simple to restore to original. Anything I have overlooked or need to consider is welcomed and encouraged.

I remember talking to one of Stuart Hegeman's technicians back in the early eighties about modifying my Hapi 2. He emphatically advised me that it was a bad idea. It seems that the topography of a preamp is very important and is taken into consideration during it's design. Adding extra RCA jacks and a selector switch might have the effect of creating an antenna to catch stray RF noise from the circuit and ruining the entire preamp. Needless to say, I took his advice. If I were to have 3 tonearms and cartridges, I would get 3 separate preamps. Keep it simple (circuit wise).