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Purifi Eval1 vs. Hypex NC252MP?

SuicideSquid

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Hi folks,

I see from searches that similar questions have been asked before, but not quite for my particular setup, so apologies for some redundancy.

I pulled the trigger yesterday on a Denon AVR-X4700H which will be used as preamp/processor for front channels and amplifier for centre/rear/height channels in a surround setup. I plan to pair the 4700 with a separate amplifier for my front channels. Fronts are Totem Forests - floor standing full range speakers with 86dB sensitivity, and the room is moderately large for a home space - 16' x 22' with 9.5' ceiling. Use will be about 80% movies and games in surround, and about 20% stereo music listening, predominantly CDs but a bit of vinyl and streaming.

I'm debating either a VTV Purifi Eval1 unit that I would clean up and port to a new case, or a 4-channel Hypex NC252MP from Buckeye (using each stereo module to biamp each speaker).

I'm not expecting there to be much of a difference between these two setups in terms of sound quality or power output, but is there any reason (other than $300 cheaper for the Hypex setup) to prefer one over the other?

Much appreciate your thoughts!
 

ironhorse128

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I replaced my nc252mp for an eval1 build to have peace of mind. The eval1 has a nice red glow coming from the regulators. Other than that there should not be much of a reason.
 

f1shb0n3

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I'm debating either a VTV Purifi Eval1 unit that I would clean up and port to a new case, or a 4-channel Hypex NC252MP from Buckeye (using each stereo module to biamp each speaker).
If you are planning to bi-amp without DSP crossover (keeping the speaker crossover board), you would be better off getting a 2 channel NC502MP instead. The benefit of bi-amping is close to zero in the typical scenario, as you are feeding separate power to the tweeter that needs no power at all compared to the bass driver so essentially you are wasting a stereo amp in this setup.
I'm not expecting there to be much of a difference between these two setups in terms of sound quality or power output, but is there any reason (other than $300 cheaper for the Hypex setup) to prefer one over the other?
Hypex modules can be bridged for a significant power increase, while Purifi doesn't support it in the typical build, unless the manufacturer made it work specifically and few has. If you get NC502MP you won't ever need to bridge it as it has sufficient power, or you can get a 4 channel NC252MP to use as either 4 channel or 2 channels bridged.
 
OP
SuicideSquid

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Thanks! I've already gone ahead an ordered a 4-channel Hypex NC252MP from Buckeye - short-term plan is to bi-amp with the built-in speaker crossover, long-term plan is to bypass the speaker crossover and use an active DSP crossover instead.
 

tvrgeek

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Don't bother bi-amping to the passive crossover. Just wait for the MiniDSP Flex to be available.

On the "subjective" forums, there seems to be a tiny preference for the Purifi. Tiny and ill defined.

I too was tempted by a Buckeye or March, but I just scored a second Hafler SE120 so I will remain AB. I can tweak a couple caps and turn it into a 70 Hz HP, second order, and with the built in crossover in the plate amp, only need the active LR4 crossover for 3K. Simplifies things. I can use my Active X-kitz until I get the Flex. Just use APO for eq. ( BSC, top end roll off, a few little hic-ups) Going to do some modeling to see if a hybrid approach is even better, making the amplifier load as predictable as possible and maybe an all-pass network as one needs at least a blocking cap to the tweeter anyway.
 

Holmz

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Don't bother bi-amping to the passive crossover. Just wait for the MiniDSP Flex to be available.

On the "subjective" forums, there seems to be a tiny preference for the Purifi. Tiny and ill defined.

I too was tempted by a Buckeye or March, …

If I was “here” (US) I would probably get a Buckeye.

However in Au the March makes a lot of sense.
And after seeing the March, it makes sense… The Buckeye seems a but Cornhusker’ish in comparison.
 
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f1shb0n3

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Thanks! I've already gone ahead an ordered a 4-channel Hypex NC252MP from Buckeye - short-term plan is to bi-amp with the built-in speaker crossover, long-term plan is to bypass the speaker crossover and use an active DSP crossover instead.
Sounds like a good plan! What speakers do you have, which are you considering to bi-amp?
 
OP
SuicideSquid

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How are you filtering the top and bottom frequency ranges apart?
Or are you just bi-amping the while signal?
I am not. As I said above, down the line I intend to remove the internal crossover and use a DSP/Active Crossover between the preamp and amplifier. But for now, just going 2 channels out to two sets of binding posts in and the internal passive crossover filters out the appropriate frequencies just as it would if you were single-amping. The tweeter path and the woofer path in the crossover are totally separate - if you're running from a single amp you have to bridge the terminals.
 
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