possible upgrade to biwire speakers

I started back in the serious realm (if not actual high end) of audio a few months ago with a Music Hall a25.2 integrated, maverick SACD player, marantz ST 7001 tuner, audioquest king cobra interconnects and type 4 speaker cable, and PSB Alpha B1 monitor speakers on sand filled sanus stands. Am now considering a slight step up in the speakers, among which the options include several biwire models. My question is whether or not such an upgrade will be worthwhile without an upgrade to biwire speaker cable at the same time.
If you biamp then you can make a modest improvement but I don't think this warrents being your main consideration in up-grading your speakers.
the ability to bi-wire is not really an assurance of better sound. the psb's are solid speakers, but an upgrade within the psb line, or going with a totem one, or another like monitor, will make a difference.
As suggested above, biwireable speakers don't necessarily guarantee better sound and shouldn't be considered as a feature when shopping for speakers. Also, non-biwireable speakers allow the use of a single run of high-quality speaker cable which will cost significantly less than a similiar cable of bi-wire configuration. There are many quality high-end speakers today which are not bi-wireable.
The real gain is to go active. Bi-wire is no different than using a heavier gauge wire—the back EMF returns to the same single amp driving the entire bandwidth and dealing with the multiple impedance curves of two or more drivers. Bi-amping may provide some benefit, but not to the extent as using an active crossover and an amp for each driver.

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