2. amps-preamps
  3. 148911-33344

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

Showing 3 responses by erik_squires

erik_squires
15,902 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
erik_squires
15,902 posts
 
Correct crossover integration with passive or active components is a giant PITA. There's no free lunch.
At best, if you have separate low and high pass filter sections, you can use set them a couple of octaves away from the actual crossover points.


For instance, setting the high pass at 1 kHz, and low pass at 5 kHz when the actual crossover is 2.8 would probably be OK.
erik_squires
15,902 posts
 
There's a couple of issues. The preamp has relatively high output impedance, making it a less than ideal candidate for using 2 amps at the same time.

The other is the possibility of having the amp gain mismatched. You'll need some way to adjust the levels appropriately.
More to discover