ET, sorry, I guess I was thinking you had a 124. Anyway, here's what I'd recommend:
1.) First, check the capacitance spec. for your cartridge and make sure you have it correct by adding the default YS capacitance to the cable capacitance and then adding additional capacitance to the phono preamp if necessary to achieve the specified capacitance for that cartridge. (This is very important for MM carts., and I think it applies to moving iron as well -- double check. It does not apply to MC carts.) If you want to keep the Rabco and TT, you might want to consider some new improved phono cables for the Rabco. Also, you'll get better bass (with that light platter) if you replace the springs with sorbothane pucks or domes (which is what they would have used in the first place if sorbothane had been available.)
2.) Keep the cartridge and sell the arm/TT together. I suspect however that your negative experience w/ MC cart. had to do with the (possibly incorrect) selection of the MC cartridge itself and/or its setup (i.e. proper cartridge loading -- you absolutely can't use 47K ohms with .2mv - .85mv MC cartridges!) Your YS with 54dB of gain has more than enough gain for any MC cartridge between .6mV and .85mV (like a van den Hul Frog for instance) But you'd have to have YS install the proper loading since the Concerto apparently doesn't provide for user adjustments.
If you want to try a quick fix (for the bass and image) lose the springs and replace them w/ sorbothane. And if you don't have one, get a good record weight to add mass to the platter and couple the record to it better. I'll bet those two things alone would make a big difference.
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1.) First, check the capacitance spec. for your cartridge and make sure you have it correct by adding the default YS capacitance to the cable capacitance and then adding additional capacitance to the phono preamp if necessary to achieve the specified capacitance for that cartridge. (This is very important for MM carts., and I think it applies to moving iron as well -- double check. It does not apply to MC carts.) If you want to keep the Rabco and TT, you might want to consider some new improved phono cables for the Rabco. Also, you'll get better bass (with that light platter) if you replace the springs with sorbothane pucks or domes (which is what they would have used in the first place if sorbothane had been available.)
2.) Keep the cartridge and sell the arm/TT together. I suspect however that your negative experience w/ MC cart. had to do with the (possibly incorrect) selection of the MC cartridge itself and/or its setup (i.e. proper cartridge loading -- you absolutely can't use 47K ohms with .2mv - .85mv MC cartridges!) Your YS with 54dB of gain has more than enough gain for any MC cartridge between .6mV and .85mV (like a van den Hul Frog for instance) But you'd have to have YS install the proper loading since the Concerto apparently doesn't provide for user adjustments.
If you want to try a quick fix (for the bass and image) lose the springs and replace them w/ sorbothane. And if you don't have one, get a good record weight to add mass to the platter and couple the record to it better. I'll bet those two things alone would make a big difference.
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