|
Title: Metrum NOS HEX DAC??!!! Post by: CoenP on March 28, 2013, 10:00:31 am Do we have a copycat?! http://www.audiostream.com/content/metrum-acoustics-hex (http://www.audiostream.com/content/metrum-acoustics-hex) "A Dutch based company....." Regards, Coen Title: Re: Metrum NOS HEX DAC??!!! Post by: PeterSt on March 28, 2013, 10:40:55 am No copycat. Just NOS as NOS is intended (and how that reviewer used it).
Disengage your upsampling and listen to ... :innocent: ... what the reviewer liked. Btw, it will be a secret that this DAC is not 24 bits (it uses "industrial" D/A chips). Nobody says so, but I do. And sometimes I am wrong. :smirk: Title: Re: Metrum NOS HEX DAC??!!! Post by: AlainGr on March 28, 2013, 11:28:00 am "industrial" ?
Title: Re: Metrum NOS HEX DAC??!!! Post by: PeterSt on March 28, 2013, 11:34:27 am Not audio.
Title: Re: Metrum NOS HEX DAC??!!! Post by: AlainGr on March 28, 2013, 11:38:56 am Sorry Peter, I am thick... I assumed there were differences between the chips you chose and theirs, but if they are not audio, then what could they be and apart from this component, where would they be used ?
Title: Re: Metrum NOS HEX DAC??!!! Post by: PeterSt on March 28, 2013, 01:27:47 pm Alain,
D/A chips are used everywhere. Could be to control the speed of your washing machine (you press a "digital" button and it is converted to voltage). Such "industrial" chips are allowed to have the most poor THD (Total Harmonic Distortion) because it is irrelevant for controlling washing machines. For fun, look here : http://www.nosminidac.nl/downloads/octavehificritic.pdf and browse to the bottom where some graphs are shown. Do notice that this is not the Hex, but it is about the "principle" I want to point out. So : When you see THD+N figures like -60.5dB @ 1KHz, this will merely be because of the NOS principle. Everybody accepts it, because it just works like that without filtering. This, however, means that the D/A chips used don't need to be "any good" at all, because their distortion and noise figures will be below this 60.5dB anyway. A bit difficiult to read (my text), but what I try to say is that where the no-filter causes THD+N to be so high, the THD+N of the electronics don't need to be so good at all. Of course this is my lay out of their provocated "modern chips" instead of good ol' audio chips like the PCM1704 we use in the NOS1, if you only know that these good ol' audio chips do 0.00034% THD+N in a working system which can be compared to their 0.04%, and which is only 100 times better or ~40dB, which you can see when you compare those plots/figures with those of the NOS1. IOW, when we'd use more poor chips, but use proper filtering in the mean time, the figures would be marginally better only compared to theirs (I don't know to what extend because I don't know what chips they use). In the mean time it is clear that "NOS" as such may sound better than the SDM (Sigma Delta Modulation) D/A chips used by about all brands ("OS"). Still you'd be listening to huge piles of distortion, with the notice that the 0.04% at 1 KHz is actually rather doable. But now show 10KHz or so, and you will see 30%. If you like that you like distortion ... Peter Title: Re: Metrum NOS HEX DAC??!!! Post by: AlainGr on March 29, 2013, 01:07:27 am Thanks Peter. There are things I have to struggle with to understand, but I certainly understand that the "good ol' audio" chips are better :)
By the way, in the documentation for the NOS1, it is mentionned that 16 chips could be put inside... Have your done this already for someone ? Or to put it differently, what would be the main improvement ? Alain |