I'm not sure if you are talking about double biwiring (2 separate sets of speaker cables) or vertical biamping. Either way, a good source of info is Vandersteen's web site. Even if you read through some of the owners manuals, both of those issues are discussed. An even better source is, if you can find them, are some of the early issues of The Audio Perfectionist Journal. Its not produced any more but the first 4 issues were free anyway. They go into great detail on this topic and many others.
Does Passive Bi amping reduces IMD InterModulation
I have heard a lot of experts say that the Passive bi amping does not reduce the IMD or intermodulation distortion.
Here is the reason why i think it reduces IMD
In transistor we have a small current at base controlling a large non linear current at output. Assume we have 2 full range channels fed into speaker with crossover HF/LF
So although both amps are amplifying full bandwidth, the output the HF side will ignore the low freq(due to cap reactance), as a result reducing the current at o/p stage of transistor and thus using a narrower region of the non linear curve and reducing the IMD. same for bass. Refer to the image link below for details.
http://postimg.org/image/95cwqkait/
[img]http://s2.postimg.org/95cwqkait/Passive_bi_Amp.jpg[/img]
It seems passive bi amping reduces IMD by increasing the headroom.
I wonder if the same effect could have been achieved by using more powerful amplifier?
Any thoughts by anyone ?
BTW i just bi amped by B&W 685 with a yamaha 573 7.1 receiver and canare 4s11 Blue jean bananas, it sounds better to me than using a single channel of amp per speaker.
Here is the reason why i think it reduces IMD
In transistor we have a small current at base controlling a large non linear current at output. Assume we have 2 full range channels fed into speaker with crossover HF/LF
So although both amps are amplifying full bandwidth, the output the HF side will ignore the low freq(due to cap reactance), as a result reducing the current at o/p stage of transistor and thus using a narrower region of the non linear curve and reducing the IMD. same for bass. Refer to the image link below for details.
http://postimg.org/image/95cwqkait/
[img]http://s2.postimg.org/95cwqkait/Passive_bi_Amp.jpg[/img]
It seems passive bi amping reduces IMD by increasing the headroom.
I wonder if the same effect could have been achieved by using more powerful amplifier?
Any thoughts by anyone ?
BTW i just bi amped by B&W 685 with a yamaha 573 7.1 receiver and canare 4s11 Blue jean bananas, it sounds better to me than using a single channel of amp per speaker.
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