Using both the Balanced and Unblanced inputs

I had both the balanced and unbalanced inputs connected on my Basis phono stage when I was comparing cables with no problems but as Nsgarch says try it carfully.

Call the manufacturer.

I have run parallel SE + BAL systems in the past, coverging at the POWER AMP. (CDP and PHONO AMP each go se to one PREAMP and bal to a 2nd PREAMP, the first PRE goes se to my POWER AMP and the other PRE goes bal to the same POWER AMP.) I always checked in first. Some said "no sweat", others said "no way". IIRC, it's a dicier move on outputs than on inputs, but I'd spend the dime on a call to be safe.

Good Luck

Marty

It all depends on how those inputs are arranged inside the amp. IF they are connected in some way all the time (ground? or negative leg?) then the power from the one that is on can go back up the line some to the one that is off and possibley cause problems. Transistors don't like current coming in backwards. (simplistic concept but just the idea
So it can be risky (cause damage) to the other source output, even if that source is turned off.

To be sure e-mail or call Mcintosh.

Or if you can read schematics, it's very easy to see if they are "connected in some way" as E. puts it. In the older Gordon Gow Commemorative Edition (the first MC275 with BAL inputs) the inputs were connected. So are the BAL and UNBAL inputs of the new (mono) 50th Anniversary MC75's.

However, I KNOW, both from the schematics and from actual operation, that the MC275 Mk IV has separated inputs. I also KNOW that the Mk V has the same circuit as the Mk IV (except no level controls on the UNBAL inputs.) However, since I haven't actually seen the Mk V scehmatics, or used one, I'm not going to guess ;--)

It won't hurt anything to try. A friend with a pair of the new MC75's tried it, and simply got crosstalk, which is how we found out that ITS input circuits ARE connected.

Neil
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