CHORD ELECTRONICS DAVE
Jun 18, 2015 at 5:29 AM Post #121 of 25,835
Yes the half band filter has much poorer timing of transients accuracy - it is in part due to the poor suppression of aliasing images as 22.0501 kHz is -6dB down, whereas an ideal infinite tap length FIR sinc filter would have infinite attenuation at 22.0501 kHz, and these errors degrade the time domain accuracy which manifests itself as poorer transient timing accuracy. But its much more complex than this!
 
The WTA filter is as you call full band filter - but as the tap length increases, it converges onto an ideal sinc filter.
 
The 16 bits refer to the accuracy of the coefficients against the ideal sinc function - so if we want to get an impulse response that has 16 bit accurate coefficients (that is the truncation of the coefficients occurs when the coefficient is below 16 bit in level), then you need about 1M taps. But what level is audible? Hugo is about 12 bits accurate against the ideal, Dave is about 14 bits - and there is a substantial difference in SQ between the two. But at what point does increasing tap length make no difference? Nobody knows the answer to that, but I will find out! There is also the issue of oversampling level, but that's another story...
 
Rob 
 
Jun 18, 2015 at 8:16 AM Post #122 of 25,835
a symmetric 1 M tap FIR linear phase filter would require just over a second for the music to start after pressing play @ 44.1 and 8x OS - can you set home theater audio latency compensation time that high? - or no movie for you
 
Jun 18, 2015 at 9:19 AM Post #123 of 25,835
Looking forward to the Dave. The technology alone makes me think it will be what I'm looking for – my respect to Rob Watts for the diligence and elaborateness with which he cares for the ultimate refinement in music reproduction. But let's see if my 65-year-old ears will justify the expense.
 
Jun 18, 2015 at 12:05 PM Post #125 of 25,835
On delay - for Dave I have an asymmetric WTA filter setting for lower delays for use with video. This works very well subjectively.
 
Dave production is scheduled for October 2015.
 
Rob 
 
Jun 20, 2015 at 6:27 AM Post #127 of 25,835
i will save for it for a year or two lol , i don't mind buying it, in fact I WANT IT SO BADLY!! 

but this time i wont stay quite about the amp section, for the price i want the amp section to be a high end, unlike the Hugo and Hugo TT which people including me are using it as a DAC

but now we are talking about a super price here for a DAC amp, so Please!!!  Chord!!, Rob Watts!!  i want the amp section to be a High End as well, 


though i highly doubt that the amp section will be good, but i am looking forward for reviews, and i want this DAC, 

---------------------
 
oh about those who complain about the price, if you don't or can't buy it then please don't bother posting... its pointless, unless you are worried about the quality when compared to Hugo Chord etc, 
 
for example and IMO the Hugo Chord TT for me didn't justify the price what so ever, because the ratio between sound quality difference and price was a rip off, and i kept using my Hugo Chord, but ofc if the ratio was good, and the TT was indeed an upgrade, then i would have bought it 100%


so people please don't hate on it , unless you confirm from reviewers about the ratio between sound and price when compared to the previous products.




man i can wait for reviews and comparisons between the Hugo TT and the Dave :p 
 
Jun 20, 2015 at 7:01 PM Post #128 of 25,835
I'm drooling for Dave. Not that there is anything wrong with that...:wink:
 
Jun 20, 2015 at 8:20 PM Post #129 of 25,835
From the interviews about DAVE with Rob Watts and John Franks as well as the extraordinary advancement in its design and processing power compared to their earlier efforts, I expect DAVE to be a very significant step forward in state of the art DAC performance and not a subtle improvement. Now we just have to wait until October to learn the full story about its performance rather than mere speculation.
 
Jun 21, 2015 at 6:28 PM Post #130 of 25,835
From the interviews about DAVE with Rob Watts and John Franks as well as the extraordinary advancement in its design and processing power compared to their earlier efforts, I expect DAVE to be a very significant step forward in state of the art DAC performance and not a subtle improvement. Now we just have to wait until October to learn the full story about its performance rather than mere speculation.


Where have you read that DAVE only going to sound subtle better than the Hugo and the TT? Its going to be much better and open up for a new dimension in DAC:s.
 
Jun 21, 2015 at 7:13 PM Post #131 of 25,835
I agree with you completely, Beolab! Some posters in various forums I have seen questioning how much better it can really be to justify its price, but looking at the extreme processing power used it should be apparent that it will be in another league of performance compared to anything else available. The time can't pass quickly enough for me to reach October...
 
Jun 22, 2015 at 1:52 PM Post #132 of 25,835
Dear Rob
 
Before Hugo I used a software called Burwen Audio - which adds space and ambiance and gets rid of the digital hardness, so changing the original date does yield very good sonic results to my ears. 
 
Quote:
   
 Of course, some people like the sound of digital hardness - the aggression gets superficially confused with detail resolution - but it quickly tires with listening fatigue, and poor timbre variation, as all instruments sound hard, etched and up front. But if you like that sound, then fine, but its not for me.
 
 This was a big intellectual stumbling block - how can changing the original data be a good thing? But the trouble with audio is that neat simplistic ideas or preconceptions get in the way. Reality is always different, and reality can only be evaluated by a careful AB listening test. So I went ahead on this idea, and listened to the first WTA filter algorithm - and indeed it made a massive improvement in SQ - a 256 tap WTA sounded much better than 2048 tap half band Kaiser, even though the data is being modified. Why is this? The job of a DAC is NOT to reproduce the data it is given, but to reproduce the analogue signal before it is sampled. The WTA filter reconstructs the timing of the original transients much more accurately than using half band filters or filters that preserve the original data and it is timing of transients that is the most important SQ aspect.
 
So the moral of the tale? Don't let a simplistic technical story get in the way of enjoying music!                
  
 Rob

 
Jun 23, 2015 at 10:25 AM Post #133 of 25,835
  I agree with you completely, Beolab! Some posters in various forums I have seen questioning how much better it can really be to justify its price, but looking at the extreme processing power used it should be apparent that it will be in another league of performance compared to anything else available. The time can't pass quickly enough for me to reach October...


Same here. I can't afford the DAVE, but still very very keen to hear what it sounds like. I am sure it will be the DAC that sets the standard for the next few years, until the million tap DAC comes out from Chord.
 
Jun 23, 2015 at 10:28 AM Post #134 of 25,835

The H
  Yes the half band filter has much poorer timing of transients accuracy - it is in part due to the poor suppression of aliasing images as 22.0501 kHz is -6dB down, whereas an ideal infinite tap length FIR sinc filter would have infinite attenuation at 22.0501 kHz, and these errors degrade the time domain accuracy which manifests itself as poorer transient timing accuracy. But its much more complex than this!
 
The WTA filter is as you call full band filter - but as the tap length increases, it converges onto an ideal sinc filter.
 
The 16 bits refer to the accuracy of the coefficients against the ideal sinc function - so if we want to get an impulse response that has 16 bit accurate coefficients (that is the truncation of the coefficients occurs when the coefficient is below 16 bit in level), then you need about 1M taps. But what level is audible? Hugo is about 12 bits accurate against the ideal, Dave is about 14 bits - and there is a substantial difference in SQ between the two. But at what point does increasing tap length make no difference? Nobody knows the answer to that, but I will find out! There is also the issue of oversampling level, but that's another story...
 
Rob 


Dear Mr Watts,  what does 12 bits accurate against the ideal mean? 
 
Jun 23, 2015 at 7:55 PM Post #135 of 25,835
On delay - for Dave I have an asymmetric WTA filter setting for lower delays for use with video. This works very well subjectively.

Dave production is scheduled for October 2015.

Rob 


Hi Rob

Will it be possible to connect a Iphone/Ipad through the apple camera kit adapter to USB and play on DAVE ?
 

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