Bi-amping with a passive XO?

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Bi-amping with a passive speaker XO?

Hi team,
Something which I've been meaning to ask for a long time...

I am aware active bi-amping which bypasses passive circuitry is an alternative to what I suggest below, but...

On the back of some speakers, theres a facility to remove plates which otherwise allows tweeter and bass to run from the same amp.

When removed, some models allow to 'bi-wire'.

In 'bi-wire' case, this 'practice' says;
1. Remove bracket
2. Per speaker; run two sets of cable to the one channel on a single amp.
3. Repeat for other speaker to same amp.

My question is more to do with running two sets of cable to two separate amps. In both cases, only a passive crossover exists between the speaker and the amp.

If the speaker only demands what the passive filter lets through, doesn't this place less demand on the amp(s) now that there's an additional one?

The 'star ground return' in the passive circuitry for these particular speakers prompted the curiosity (see attachment).

"Our use of full star return circuitry on the crossover boards extends this technique [bi-wiring] to the individual filter components with further improvements in sound quality."

Any one got some light on this?

EDIT: I can for instance with these rogers speakers, run the tweeter and bass entirely separately,
i.e. with the tweeter amp off, only the bass plays.
 

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The amplifier sends the same signal to the woofer and tweeter part, compared to regular single amping. The woofer part only draws current at low frequencies and not at high ones anymore. Vice versa for the tweeter part. So less demand is placed on the power supply and the rails will hold up better. Therefore the amplifier can deliver a slightly higher voltage (amplifiers are voltage sources).

Low and high frequencies do not interact with eachother in speaker wire. Speaker wire is almost perfectly linear, so the low and high frequencies are just superposed. The interaction that happens inside the amplifier still happens with this form of bi amping, altough it is questionable whether it is significant.

Superposition on Wikipedia

Star earth is not relevant at loudspeaker crossovers, where wires are short and thick and frequencies are 'low'.
 
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So less demand is placed on the power supply and the rails will hold up better. Therefore the amplifier can deliver a slightly higher voltage (amplifiers are voltage sources).

[...]The interaction that happens inside the amplifier still happens with this form of bi amping, altough it is questionable whether it is significant.

Superposition on Wikipedia

Star earth is not relevant at loudspeaker crossovers, where wires are short and thick and frequencies are 'low'.

Ah well my primary curiosity really was if IMD (as reduced in active equivalent) is also reduced by this method I suggest.
I realize each xo portion are mixed in the amp still.

As for star ground return, it was in the marketing booklet supplied with the speakers. It mentions bi-wiring which I realize was largely known to have negligible effect (a gimmick in essence).

But Bi-wiring aside, is passive bi-amping with two amps as opposed to one a good idea (regarding IMD)?
I just wonder if this has been largely overlooked..

EDIT: I can for instance with these rogers speakers, run the tweeter and bass entirely separately,
i.e. with the tweeter amp off, only the bass is plays.
Rogers were passive crossover 'masterminds', apparently.
 
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But Bi-wiring aside, is passive bi-amping with two amps as opposed to one a good idea (regarding IMD)?
I just wonder if this has been largely overlooked..
It should reduce the IMD that the amplifier produces however in the scheme of things it's pretty futile as it does nothing to help address speaker IMD which will already be at a much higher level than amplifier IMD. If you already have an extra amplifier which is as good/better than your existing one then it doesn't hurt to try.
 
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