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Opinions on Hypex Plate (FusionAMP) Amplifiers?

voodooless

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Hypex are very transparent about their products :). but you made it as if I'm not doing an apples to apple comparison but I actually was.

Agreed on that mostly. The Apple dongle still doesn't give you an extensive DSP engine.. and a Fusion amp doesn't fit in your pocket. Some strange apples they are.

Actually, I made a mistake of one zero earlier :facepalm:: the Ncore has -90/-92 dB THD (NC250MP, 1W/half power). So actually, it doesn't really matter that the DAC is just 100 or 110 SINAD. That also explains why the fusion manual states the same data.. it does not include the amp section.
 
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abdo123

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So actually, it doesn't really matter that the DAC is just 100 or 110 SINAD.

That's far from true tbh.

A theoretical 120dB S/N DAC will have a 4uV residual with respect to its 4V output (assuming bal XLR).

A typical amplifier has around 29dB of gain. That is a voltage gain of 28 times.

You now have 112uV (~0.1mV) from amplifying just the residual noise from the connected D/A converter. And the residual of the amplifier itself.

A really good power amplifier with say 150WPC may have a S/N of 120dB plus (NC252MP for example), which will mean a residual of around 35uV, so the D/A's contribution is well over three times the amplifier's and the two will combine to become audible when the volume is high. That example would result in a S/N of ~107dB, a degradation of 13dB from a 120dB rated amplifier.

And of course, once we go down in level from 120 dB S/N ratio DAC, we are into the 70s and 80s for sure.
 

YSDR

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my MiniDSP 2*4 HD has a S/N of ~107 dB and I can hear the hiss loud and clear at night.

these noise levels (assuming they will be amplified further by the amplifiers) are audible and frankly annoying. This is not yet the extreme insignficant case that you're making it out to be.
True that I was not totally precise with my comments. Sorry for that! Yeah, I can hear a hiss with my 109dB/2.83V sensitive tweeter when connected directly to the Fusionamp, but only hearable when the room is quiet, and no music or any other sound comes from the speakers, only just turned on the system. But since I padded down the tweeter by 11dB with a speaker level L-pad, the audible hiss has gone.
So if the Fusionamp would have 11dB lower noise floor, then I shouldn't need the -11dB L-pad for that performance with my (otherwise very high sensitivity) tweeter.

It would have been more correct for me to write that there is no audible difference between the digital and analog inputs of the Fusionamp if the analog source is also good enough for that.
 
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voodooless

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That's far from true tbh.

Agreed. I already mentioned that the SNR of the amp is two orders of magnitude better than the DAC. Distortion is however one order of magnitude worse. Pick your battles I guess.
 

YSDR

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Agreed. I already mentioned that the SNR of the amp is two orders of magnitude better than the DAC. Distortion is however one order of magnitude worse. Pick your battles I guess.
I would pick the higher harmonic distortion, because the loudspeaker drivers usually three order of magnitude worse in this regard. So in theory, the harmonic distortion of the amp (plus DAC, plus whatever) would be masked by the distortion of the loudspeaker anyway. Or not?
 
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sigbergaudio

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my MiniDSP 2*4 HD has a S/N of ~107 dB and I can hear the hiss loud and clear at night.

these noise levels (assuming they will be amplified further by the amplifiers) are audible and frankly annoying. This is not yet the extreme insignficant case that you're making it out to be.

The hiss from our speakers is inaudible from 50cm away when connected to a mid-fi AVR with maybe 90dB SINAD, so you either don't have a 107dB SINAD end-to-end, and/or there's something in the gain structure of your system that is amplifying some kind of noise source. You don't need 100dB+ SINAD to avoid hiss.
 

Plcamp

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my MiniDSP 2*4 HD has a S/N of ~107 dB and I can hear the hiss loud and clear at night
I found in my room that replacing the supplied power supply with an ancient one from a ZIP drive (remember those?) made minidsp quieter. I also had noise issues when usb from a computer connected, that was helped with clamp on ferrites. Not sure you get 107db including these noise contributions from cables, I think it’s typically higher noise.
 
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abdo123

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I found in my room that replacing the supplied power supply with an ancient one from a ZIP drive (remember those?) made minidsp quieter. I also had noise issues when usb from a computer connected, that was helped with clamp on ferrites. Not sure you get 107db including these noise contributions from cables, I think it’s typically higher noise.

well it scored that way when Amir measured it on the previous analyzer. it's probably a little bit lower, but not much.

I've been thinking of getting the ifi active noise cancelation filter. since it should work with any power supply in the future as well.
 

Kelims

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There will be a new version in the near future. DSP has been upgraded from adau1450 to 1452. A larger pic controller was needed because there was no space left. And yes, Fir's on the input and output channels.
Hello, do you have any specific information on when the new DSP will be available for sale? Will it be possible to exchange an existing unit for a new one?
 

voodooless

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Hello, do you have any specific information on when the new DSP will be available for sale? Will it be possible to exchange an existing unit for a new one?
Good question! That post is almost 2 1/2 years old now.. where is the actual product? Starts to sound like Duke Nukem Forever... At least that came out eventually ;)
 

DS23MAN

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With the ongoing parts and coronacrisis it is impossible to introduce new product's. It is a pain in the ass to keep up production for existing customers.
 

voodooless

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With the ongoing parts and coronacrisis it is impossible to introduce new product's. It is a pain in the ass to keep up production for existing customers.
Bummer :( One would think that sourcing adau1452 would be just as hard as adau1450? The price difference is negligible, so just switch :)

Obviously, the real world is far more complex than that :mad:
 

MCH

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My boss' view: it is an unique chance to introduce new products to customers that are having trouble sourcing what they were using until now. I must say he has a point.
 

DS23MAN

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It's not about a specific part but all parts, shortages in resistors, cap's, powerfets and so on. All manufactures are having these problems.
 

voodooless

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It's not about a specific part but all parts, shortages in resistors, cap's, powerfets and so on. All manufactures are having these problems.
That's the whole point, what does it then matter if you change one part ;) At least you can make customers happy, even if they can't buy your new product (yet). At least it exists :cool:. It will prevent (some of) them from looking elsewhere.
 
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