Hello!
Josh,
To use the RIAA's in a true differential ballanced design (one with mirror image signal paths) would take 2 sets of riaa's - one in the +leg and one in the -leg. You'd need some way to derive a center point from the cartridge at the input stage - until they make a cartrige with a center tap on the coils...... I have a pair of tx103's here that were wound with a center point and I use them from time to time with my bal input haggerman trumpet - works great. As Bica I think suggests I'd tend to use Allen's design's as is since a lot of thought goes into them and I suspect mutations like strapping a RIAA in the middle would not be optimized.
Bica,
Thansk for the link! Good reading - as is the rest of Allen's stuff! You'd need to add that eq outside the RIAA but I will bounce it off S&B when we next talk and see if he has heard of it or considdered it. Also you are right - especially in the case of the tx103 break-in outside the circuit is required. This makes sense when you think just how little signal comes from the cartridge....... This would be less of a factor with the RIAA which, like the tx102's, will see a more respectable signal level in normal operation.
Thansk!
John