I'd like to build a multichannel amplifier for center and surround channels. The problem is what to do with the center channel amp. I thought about using NC122MP modules and maybe bridge the center channel amp. It maybe sounds different than main channel's Purifi, but the center channel speaker is different, so that already causes differences. Or maybe I should use cheaper Icepower modules for surrounds (but those offer just unbalanced input) and use NC400 for center...Yes I hear these amps on a daily basis, I manufacture them. Although I confess I haven't heard a nc400 in a long time.
The NcxxxMP modules all tonally sound extremely similar. Power is the differentiator. They are lower performance modules below Nc400, 500 and 1200.
The Purifi sounds better than 400, 500 and 1200 IMO. However it's not that simple. If you have evil low impedance low sensitivity speakers you may need the drive capability of the 1200. In that circumstance the 1200 may well sound better.
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DIY Purifi Amp builds
- Thread starter JimB
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Dimitri
Senior Member
I might have missed the whole boat. I was going by the thread title. I'm not trying to keep up with which amp is a commercial offering and which one was bolted together by the owner for their own personal use.
I do know all this discussion is making my screwdriver hand itchy and my soldering iron is about to start complaining.
Putting aside that being able to diy with a NCxxxMP means you find them "fallen from the delivery truck", the NC250MP is cheaper and more powerful than the NC122MP.
somebodyelse
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Or you bought a FusionAmp and removed them from the plate.
Looks like I may have to do that.
NC250MP for the center channel is probably a better option than bridged NC122MP.
Please relate your testing protocol. Double blind testing? Sample size? Etc. "Sounding better" is a subjective opinion and indeed, meaningless.
The objective performance differences between these two amps is beyond minuscule and thus hearing any difference related to the amps themselves begs belief.
Seems to me that if you are going to hold others feet to the fire when it comes to scientifically valid testing, you ought to hold yourself to the same standard.
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OP
- Thread Starter
- #807
Well, maybe it's helpful for some to decide whether it is worth it to them to go DIY? Don't let it deter you from building!I might have missed the whole boat. I was going by the thread title. I'm not trying to keep up with which amp is a commercial offering and which one was bolted together by the owner for their own personal use.
I do know all this discussion is making my screwdriver hand itchy and my soldering iron is about to start complaining.
Thing is the centre channel is the most important in home theatre, so I wouldn't skimp on the the amp if possible. However if cost is an issue bridging the Nc122mp works fine. I have several customers doing exactly what you suggest.
In this context you are very unlikely to hear differences between the amps. The different centre speaker will make far more of a change to the sound.
Personally I think the Hypex amps beat the Ice by a fair margin both technically and in sound.
Why have you said that when you have no idea how I test. You are clearly being provocative and trolling for an argument.
As I already said It's blind. Roon simultaneously drives 2 identical dacs in different zones. Volume is trimmed and matched by Roon and voltage measured to be identical at the speaker terminals.
A switch box allows the subject to fast switch between the 2 amps as often as like when they like. They can listen to whatever tracks they like for as long as they like.
Regarding the Purifi I have tested 22 people. Yes it could be more but there is a consistent feedback about the sound.
Regarding technical differences between the amps you are simply not looking close enough. The major difference people comment on is they perceive a more extended "sweeter" high frequency range. Take a look and you will see the Purifi doesn't have the roll off the Hypex do. Very small shifts in frequency response over wide frequency ranges are quite noticeable.
The Purifi measures better and people like its sound more. Nothing meaningless about that.
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Honestly, I had the same question. It's legit, and I'd have no problem with you asking me this were I to say something similar. Where can I find a Hypex response curve? I'm surprised by the claim that it's not flat in the treble, but I have no direct experience with it and data answers everything.
FWIW, I did level matched comparison between the Purifi and two other amps and never got to the blinded stage- the sound was indistinguishable to me.
True, if you can find one. Remember all of the ncxxxmp amps are officially OEM supply only. Whilst they are extremely reliable Hypex may not honour warranties with private individuals who have bought them through unofficial routes.
Honestly, I had the same question. It's legit, and I'd have no problem with you asking me this were I to say something similar. Where can I find a Hypex response curve? I'm surprised by the claim that it's not flat in the treble, but I have no direct experience with it and data answers everything.
FWIW, I did level matched comparison between the Purifi and two other amps and never got to the blinded stage- the sound was indistinguishable to me.
It is certainly a legit question, I just object to goyrus other comments, tone and implication.
All the Hypex are about 0.6 dB down by 20kHz. The extensive datasheets are on their website have the plots. Same curve confirmed by Amir's various measurements.
Is it a massive difference in sound? No, but nonetheless people can identify it.
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I will confess that I'd be unlikely to hear -0.6dB at 20kHz. You must be using younger listeners... which is not a bad idea, if so.
Just looking back through Tooles book he does have a paragraph on the audibility of spectral tilt. He says there is evidence that 0.1dB to 0.2dB per octave is audible.
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Some people, possibly. Most people, doubtful.
You have no basis for that statement and you haven't heard the amps.
The research contradicts your thoughts. As mentioned it shows people can hear tilts in frequency response as small as 0.1 / 0.2dB per octave.
