Audio Asylum Thread Printer
Get a view of an entire thread on one page
|For Sale Ads|
In Reply to: RE: Please explain bi-amp crossover to me posted by Raymond Leggs on February 21, 2017 at 14:57:12
I think Richard Vandersteen got it right: bi-amping makes a pretty dramatic improvement in low-level detail, as does bi-wiring. But he found that bi-wiring only worked when the wire pairs were kept separated by an inch or two for most of their run. I found a somewhat abbreviated version of his original paper on this - see link.
In the original paper, he wrote of hearing improvements in low-level detail with bi-amping. Then he made up two amplifiers with a single pair of outputs - two power supplies, two input sections, two output sections linked to a single pair of terminals. No improvement. He tried bi-wiring with the wire pairs in a common sheath, and heard no improvement. When he separated the wire pairs, he heard an improvement. Using a Hall effect meter to measure the magnetic field generated by the current in the wire pairs, the level of the field was much greater for the woofer pair than the tweeter pair. As the inverse of the Hall effect also applies, i.e. that the magnetic field around the wire pair can affect the current, he concluded that was what was going on.
To the OP's original post, the crossover of a two-way speaker consists of a circuit with two branches: one with a high-pass filter going to the tweeter, and the other with a low-pass filter going to the woofer. Connecting the branches via the jumper wires at the terminals gives you the option of using the speakers mono-wired. BTW, it's not something on "cheap speakers," and that couple inches of wire is not something to go "eekers" about. There's lots more wire inside the box, and lots more connecting the speakers to the amplifiers, so I don't think the couple inches of jumper wire is something to get overly concerned about.
Many people don't buy Vandersteen's explanation, but some who do are often worth listening to. When I sent pics of my modified-for-biwiring Spica TC-50 crossover boards to John Bau, he agreed it should make a big improvement, though he thought it was due to ground plane interactions more than Hall effect.
BTW, there is an easy way for many of you to test this. If you are set up for bi-wiring with the wire pairs in a common sheath, cut the sheath off, separate the wires by an inch or two, and let us know if you hear any difference.
Some day we actually might get this figured out.
"A man need merely light the filaments of his receiving set and the world's greatest artists will perform for him." Alfred N. Goldsmith, RCA, 1922
Edits: 02/24/17Follow Ups:
Vandersteen. Lots of words but no data.
So where exactly do you disagree with Vandersteen's ideas about bi-amping?
Once thought Vandys were Outstanding. Then.. Lived with some.
They Aren't.. Period.
Emperor's clothes IMO, is an honest descriptor.
No One should care what Vandersteen claims.. these days.
His 15 mins of fame is OVER.. adapt to the 21st century reality.
Post a Followup:
Post a Message!
This post is made possible by the generous support of people like you and our sponsors: