Hi,
Are MC cartridges prone to damage in shipping such that ground loops in otherwise fine systems become common, or is it me? I recently bought my first MC cartridge, Rega Ania Pro, to replace an Exact II. I mounted the Ania Pro, changed the JC3+ back pannel setting to MC 50-500 ohms, readjusted the arm and I got ground hum. I retraced my steps, re-mounded & adjusted again, but the hum remained. I had made no other adjustments to an otherwise fine sounding system [no I did not also take the opportunity to add a microwave oven, router or a garage door motor to the circuit]. When I switched to DAC at the preamp, there was no ground loop, so I figured it must be up-stream and not because the preamp had become some kind of nexus of uneven grounds. The head shell leads looked tight and unfrayed; I readjusted the RCAs into the JC3+, the ground lead going from the preamp (which never seemed to make a difference) and the XLRs from the JC3+ to the preamp. Everything looked fine, but the hum remained. So, I removed the Ania Pro, reinserted the Exact II and the ground loop was gone.
I returned the MC to the retailer on the assumption that it must be defective and am now awaiting a replacement; however, doubts remain, because I have a rather complex system, and I know how tricky ground loops can be to isolate. Everything becomes suspect, even cables (I once traced a loop to defective wire in a Monoprice XLR cable). So I'm wondering did I overlook something or are MC cartridges just that fragile.
Are MC cartridges prone to damage in shipping such that ground loops in otherwise fine systems become common, or is it me? I recently bought my first MC cartridge, Rega Ania Pro, to replace an Exact II. I mounted the Ania Pro, changed the JC3+ back pannel setting to MC 50-500 ohms, readjusted the arm and I got ground hum. I retraced my steps, re-mounded & adjusted again, but the hum remained. I had made no other adjustments to an otherwise fine sounding system [no I did not also take the opportunity to add a microwave oven, router or a garage door motor to the circuit]. When I switched to DAC at the preamp, there was no ground loop, so I figured it must be up-stream and not because the preamp had become some kind of nexus of uneven grounds. The head shell leads looked tight and unfrayed; I readjusted the RCAs into the JC3+, the ground lead going from the preamp (which never seemed to make a difference) and the XLRs from the JC3+ to the preamp. Everything looked fine, but the hum remained. So, I removed the Ania Pro, reinserted the Exact II and the ground loop was gone.
I returned the MC to the retailer on the assumption that it must be defective and am now awaiting a replacement; however, doubts remain, because I have a rather complex system, and I know how tricky ground loops can be to isolate. Everything becomes suspect, even cables (I once traced a loop to defective wire in a Monoprice XLR cable). So I'm wondering did I overlook something or are MC cartridges just that fragile.