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Bi amp pros out there I could use some help! First time Bi Amping...

Just picked up a BAT vk 200 for the bass and using my Pass Aleph 5 for the mids and tweets. Ive never played around with bi amping so I apologize in advance for any lame questions My speakers are Dunlavy SC3's original 5.5 nominal load. The pass is 90 wpc at 4 Ohm and the BAT is 200 wpc at 4 ohm so Im guessing around 75 wpc off the Pass Amp and 150 plus with the Bat Amp. My pre amp is a Aleph P and Im running the Single ended through a XLR adaptor (cause the Bat is Balanced inputs only) and the pass Aleph 5 off the XLR outputs of the pre and inputs of the Pass amp. The PASS Pre Amp manual says there is a 6db differential between the RCA and XLR outputs  two and both can be driven at the same time. So the RCA is 9db and the XLR is 15 db. Gain is within 2db on each amp. So whats the best way to do this? Get a custom XLR "Y" connector and drive both off the XLR output of the pre? Or is there a way better way to get the magic? This is past my "WORLD" Map and experience so Id thought Id ask for the smart people for advice. 

Thank you in advance!

-ALLGOOD
128x128haywood310
bdp24's avatar
bdp24
9,821 posts
 

Right you are George, but some power amps (for instance my Music Reference RM-200 Mk.2) have (true) balanced inputs (created by Modjeski with discrete components, no opamps or transformers. He's a very clever designer) only, and some pre-amps have (true) balanced outputs only (Atma-Sphere's, for example).

I'm sure the Pass x/o provides benefits over the First Watt B4 other than balanced outputs, but that to me is academic. I don't have the $ for the Pass!

georgehifi's avatar
georgehifi
10,312 posts
 

If interconnects are shielded and kept to a reasonable length, I believe there are no "sonic" advantages for XLR over SE.
But there is a real "sonic advantage" for SE over "pseudo XLR" as as I mentioned before (about balanced op-amps in the signal path with "pseudo XLR").

Lampizators view on it.
http://www.lampizator.eu/LAMPIZATOR/Balancedornot.html

Stereophiles 4 page article on it.
https://www.stereophile.com/features/335/index.html

Cheers George
bdp24's avatar
bdp24
9,821 posts
 

Yes George, and we all owe Ralph Karsten a debt of gratitude for bringing to our attention (mine anyway) the matter of the AES standard for balanced connections---which wires get soldered to which XLR pins. Of course, if your "balanced" output is called that only because it is on XLR jacks (the output being in no way truly balanced), the balanced cable won’t get you any benefits anyway. And learning that some gear is made with its’ pseudo-balanced and single-ended outputs wired together shocked me. How lame!

I’m sure Ralph will have a counter-argument to that of Martin Colloms in the Stereophile article!

sleepwalker65's avatar
sleepwalker65
832 posts
 
Even a pseudo-balanced cable (twisted pair inside a 100% braid shield tied to chassis ground at one end only) is sonically superior to pseudo-shielded unbalanced cables. 
erik_squires
16,152 posts
 
FTR: In my experience, it is MORE common to see XLR sockets on unbalanced INPUTS than on XLR outputs.

I’ve seen both professional (Yamaha) and consumer (Parasound) amps with this "feature. " The Parasound A23 for instance, but not the A21.

It’s basically convenience, to allow pro cables to work, but it defeats the noise cancelling properties of a balanced transmission, and accomplished by grounding the (-) pin at the socket.


Best,
E
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