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Using XLR for Phono out

Hi folks, I am setting up my stereo on paper first and have an interesting question. I have bought a PS Audio GCPH phono preamp. It has RCA inputs for phone but output
can be RCA or XLR! PSAudio states their amp is all balanced. I am using a VPI JWM tonearm that has direct RCA outputs. I am using XLR from preamp Cambridge 840E to my Marklevinson 336. Should I use the XLR phono output to the preamp too? Thanks, Rique.
spaninc
lewm
13,598 posts
 
Cool. But I was not totally wrong; you need to feed a balanced signal to the primary. I don't know why one would want to convert a perfectly good balanced signal to SE, except if you are a transformer-phile. (I'm just kidding; you probably have sound justification for this approach.)
john_tracy
344 posts
 
Manufacturers do it because SE is cheaper (half the number of parts ;-) ). In phono preamps, designers have traditionally used SE architecture because adding the other half for balanced will increase the inherent circuit noise. That would be a good example. The MC pick-up is naturally balanced. Connecting it that way to the primary of an MC input transformer, then connecting the secondary SE is quite common.
nandric's avatar
nandric
4,086 posts
 
John (12-19-09),'a potential fly'. In the context of (ASR)
Basis Exclusive I mentioned the recommendation from Schaefer (ASR owner) to use RCA out when using balanced inputs. Alas I was not able to explain the issue. But your
statements regarding the OP amps may explain the 'actual fly' in connection with Basis Exclusive?
Regards,
atmasphere's avatar
atmasphere
12,116 posts
 
John_tracy, just for the record, to do things balanced does not double the parts (its about 50% more) and the noise is actually **lower** for a given stage of gain, not higher! The noise is theoretically 6 db less per given stage of gain; this can really add up over several stages so when you are done, you often can get by with less gain stages overall.
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