Does Bi-amping really make a difference in sound?


I have really been torn in the past week in how I should improve my Home theater stereo System. I presently own the following gear:

Oppo Blu-ray Player
Yaqin Tube Buffer (w/ 6SN7 Tung Sol Oval plate Tubes)
Cambridge Audio DAC Magic
NAD C-375 Integrated Amplifier
PSB Synchrony Two loudspeakers
Nordost Red Dawn Ics
Audioquest VDM-X Digital Cable

An experienced audiophile and design engineer who designs speakers and custom electronic gear has told me that in order to improve my sound drastically I need to Bi-amp my speakers. Since PSB speakers have separate crossovers for the tweeter/mid and bass, that I could take advantage of this and bi-amp them and really make them sing.

I was told that I should buy a another amplifier and use the Pre outs of the NAD C-375 Integrated amp and even tailor my sound by selecting the appropriate amp with the same power wattage.
I am thinking of getting an NAD C-275 or the Vincent Audio SP-331 Power Amp to connect to the Pre outs of my NAD C-375 and bi-amp my speakers with two sets of Harmonic Technology Melody cables running shotgun to my speakers.

I also plan to upgrade my digital cable to the HT Digital Silver cable and maybe the HT Silway link Silver to my DAC to NAD C-375 connection over my present Nordost Red Dawn.

My dealer friend disagrees with my approach that bi-amping will improve my sound as he said he conducted a similar setup with the PSB Synchrony Ones in his store and did not hear any differences. I am wondering if he is just wants to steer me in the direction of getting a Rogue Audio Preamp and NAD C-275 combination, which I have considered as well.

Any expertise and advice in this situation would be greatly appreciated. I unfortunately cannot tryout these situations or go listen to them in a store due to my location and have to rely on people’s advice.
rlh157
My $.02 on your using Tung Sol Round Plate in a tube buffer. I think it is a shame to use those precious nearly extinct tube for that purpose. A tube buffer is just that, a buffer, where the tubes aid in matching impedances between to other pieces of gear. In your set up I failed to see a real need for a tube buffer at all.
Instead get a 6SN7 based preamp if you really want to hear what those extremely valuable tubes can do. Try them in a gain stage if they are not burned out or microphonic. If microphonic they can also have a significant but less well heard impact as driver tubes.
Another thought would be to buy an integrated with a tubed preamp section although I don't know any off the top of my head any hybrid SS integrated that uses them as the preamp gain stage. Many all tube integrateds use them as drivers or possibly phase splitters and inverters but not usually.
Any of those chioces will have a big impact on your sound. As for biamping I think if you get the right external active X-over you can use SS amps for the woofers and tube amps on top. This is a logical but evidently difficult approach to improving sound.
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Mechans, trust me, I thought the same thing. I got the tube buffer to economically introduce tube sound into the digital sources. I have already gotten an RMA# for the Tube Buffer as I am thinking of sending it back, and my heart feels I should get a Rogue 99, which can use those precious 6SN7s. I also have a pair of Sylvania WGT/As as well to compliment that Rogue Preamp.

I am thinking along the same lines that this bi-amp represents a huge risk for potential great disappointment given the money I would have to invest. I think logically I am much safer in getting either a Rogue Integrated Amp, or Rogue 99 Preamp and Solid State amp combination.

I use to own BAT gear some years back and crave that tube heaven again. I use to own a BAT VK-60 amp and a BAT VK-3i preamp, along with a MMF 7.1 Turntable, and Vandersteen 2ci speakers. Trying to slowly get back to that level. I just have given up on Analog and using only digital sources now.
I have heard great biamplified systems, both active and passive, and I have also heard great monoamplified systems (many more of them). The great monoamplified systems never made me think, "Now what this system needs is biamplification."

Which leads me to conclude that UHF Magazine was right when they wrote "one great amp will beat two lesser ones", and that there is some great advice in this thread.
I agree with Elizabeth 100% on this. If you are stuck on Bi amping, I would recommend active crossovers. This takes out the input/output voltage and impedance matching issues that is the abundance of the problem. You can then dial in frequency and volume and is much easier to match.
Good active crossovers are expensive. I think you will find as already suggested that a better amp would make more of a difference. Good Listening, Tim