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post #2311 of 3640
I have the latest driver. I just found out that the strange/different behaviour was caused by the update of jriver: in particular in the audio setting of the control panel the default audio device was "jriver something" instead of AudioGD. I adjusted everything and now the sound is back to Normal..so now I'm happy with AudioGD KS
post #2312 of 3640
Quote:
Originally Posted by lieberung View Post
 

Out of curiosity, what is the purpose and benefit of having more dac chips in a dac (in this instance 8 pcm1704 instead of instead of 2 usually found in most dac with this chip). What does more chips bring to the table`?


Two chips per channel gives you fully balance operation, smooths out linearity issues, and provides better S/N and low level resolution over a single chip.   The electrical current output of the DAC chips are relatively small so by doubling up to four chips per side in a balanced arrangement effectively halves their output impedance.  The quad DAC chips can react faster to dynamic changes and also better at resolving low level detail.   I also have the AGD Reference 5.32, a balance four chip PCM1704K DAC.   The sound quality is similar the Master 7 but the latter is indeed more dynamic and has better resolution.   So two chips per side gives you a fully balanced channel.   Doubling up to four chips per side adds more drive capability.


Edited by DACLadder - 11/29/14 at 7:58am
post #2313 of 3640
I think I am going to leave the PLL option off. When I first bypassed PLL the bass sounded lighter to me and I thought that may have been the result of increased jitter. But after further listening the other hallmarks of increased jitter (tinny treble, thin untextured midrange) never reared their heads. The bass is more detailed and palpable and the midrange cleared up some while at the same time seems to have more body. biggrin.gif

I think if you have a good usb to I2S like the Offramp or Transient or others that use really good clocks, you will probably like what you hear with PLL turned off.
post #2314 of 3640
Quote:
Originally Posted by ciphercomplete View Post

I think I am going to leave the PLL option off. When I first bypassed PLL the bass sounded lighter to me and I thought that may have been the result of increased jitter. But after further listening the other hallmarks of increased jitter (tinny treble, thin untextured midrange) never reared their heads. The bass is more detailed and palpable and the midrange cleared up some while at the same time seems to have more body. biggrin.gif

I think if you have a good usb to I2S like the Offramp or Transient or others that use really good clocks, you will probably like what you hear with PLL turned off.

Can you please show a photo on the jumper to bypass PLL?

post #2315 of 3640
Quote:
Originally Posted by aljordan View Post
 

 

Hi Josh,

 

Yes, you are correct.  Setting jumpers 4 and 5 is a better way of putting the DAC into NOS mode because you can still have the other filters engaged as desired.  Sorry, I missed that question in your earlier post.

 

Alan

I don’t know much about this, but isn’t the main reason for going into NOS that you can skip the nasty digital filter like AN do?

 

One other question I have is why can’t one bypass the DSP and the whole oversampling mode with the OR5 i2s, but with the OR5 SPDIF via coax?

post #2316 of 3640
Quote:
Originally Posted by Articnoise View Post
 

I don’t know much about this, but isn’t the main reason for going into NOS that you can skip the nasty digital filter like AN do?

 

One other question I have is why can’t one bypass the DSP and the whole oversampling mode with the OR5 i2s, but with the OR5 SPDIF via coax?

 

From a technical standpoint I would not consider the digital filter nasty.  A filterless DAC will have all sorts of out-of-band images bounced back into the audible frequency band, among other issues.  From a sound standpoint, I suppose it comes down to preference.  I know some people love them.  Many years ago I owned a filterless NOS DAC for a short while.  It sounded very good on certain styles of recordings such as acoustic guitar based folk music.  But the sound became jumbled as as the music became more complex.  I sold it after a few months.  In any event, if you have high  bandwidth in your downstream equipment, it would make sense to run some sort of filter as there are conditions where you could be throwing a lot of high frequency garbage at your tweeters.

 

I can't help you with the i2s question. I've never looked into it as I've been very happy with the Berkeley converter.

post #2317 of 3640
Quote:
Originally Posted by aljordan View Post
 

 

From a technical standpoint I would not consider the digital filter nasty.  A filterless DAC will have all sorts of out-of-band images bounced back into the audible frequency band, among other issues.  From a sound standpoint, I suppose it comes down to preference.  I know some people love them.  Many years ago I owned a filterless NOS DAC for a short while.  It sounded very good on certain styles of recordings such as acoustic guitar based folk music.  But the sound became jumbled as as the music became more complex.  I sold it after a few months.  In any event, if you have high  bandwidth in your downstream equipment, it would make sense to run some sort of filter as there are conditions where you could be throwing a lot of high frequency garbage at your tweeters.

 

I can't help you with the i2s question. I've never looked into it as I've been very happy with the Berkeley converter.

 

Okay, may be the digital filters isn’t nasty per se, but it seems like many of the ones implemented in today’s budget and midrange dacs inflict negative on SQ. Companies like Schiit and Chord for example deals with the problem by developing better and more advanced filters to address the problem. The other solution is to not use filters at all in the signal path like AN’s nos DACs. Their approach isn’t totally filter less, they still have filter on power, work on good isolation and other things to prevent noise to reach the music signal and cause trouble – One can say they work on preventing rather than solving a problem…or something like that :D

 

Only because the filters operates in the digital domain doesn’t make it problem free. I don’t buy in to this it’s only 1 and 0 thing and have never done (I don’t imply that you is of this opinion).  I like to turn it 180 degree, who would accept heavily filtering in the analog music signal path?

 

It’s my understanding that, and I could be wrong, up-sampling is almost impossible to do without filters. In Audio Notes older DACs they used both digital filters as up sampling. Then they did a major change and started with non-up sampling and no digital filters and I don’t think they did this because of problem with up sampling per se (my speculation).

 

I have tried to up sample 44.1 to both 88.2 and higher in different media players and the result is really awful IMO. So the question is can a dac really do this without losing the natural richness and soul and not make the music sound flat, gray and sterile as so many digital sources do, IMHO? Most likely they can do it better when I do this on a PC software I would say, but probably with some sort of negative effect.   

post #2318 of 3640
Quote:
Originally Posted by Articnoise View Post
 

Can you please show a photo on the jumper to bypass PLL?

http://www.audio-gd.com/Master/Master-7/M7EN_Use.htm    See the bottom of the page (PLLEN).

 

I'm going to look for a jumper and bypass the PLL.   Something I have been meaning to try for a while.  The hardest part will be finding a jumper!

 

Edit: Jumper ON - PLL Bypassed!   With Off Ramp 5 HDMI I2S I am hearing good bass and maybe slightly less grain in the highs.  My usual increase of jitter symptoms are weaker bass, fuzzy highs, and increased silibance.  But don't notice an increase in these artifacts.  Not a dramatic difference though that will require longer listening to evaluate.   But encouraging nonetheless.  


Edited by DACLadder - 11/30/14 at 9:04am
post #2319 of 3640
Quote:
Originally Posted by DACLadder View Post
 

http://www.audio-gd.com/Master/Master-7/M7EN_Use.htm    See the bottom of the page (PLLEN).

 

I'm going to look for a jumper and bypass the PLL.   Something I have been meaning to try for a while.  The hardest part will be finding a jumper!

 

Edit: Jumper ON - PLL Bypassed!   With Off Ramp 5 HDMI I2S I am hearing good bass and maybe slightly less grain in the highs.  My usual increase of jitter symptoms are weaker bass, fuzzy highs, and increased silibance.  But don't notice an increase in these artifacts.  Not a dramatic difference though that will require longer listening to evaluate.   But encouraging nonetheless.  

 

Dacladder do you know if one can bypass the up sampling and filters with the OR5 i2s?

 

And if it’s not too much trouble can you please take a photo on the jumper then in its bypassing the PLL?

post #2320 of 3640
Quote:
Originally Posted by Articnoise View Post
 

 

Dacladder do you know if one can bypass the up sampling and filters with the OR5 i2s?

 

And if it’s not too much trouble can you please take a photo on the jumper then in its bypassing the PLL?


In the link provided earlier there is an excellent photograph of the jumper headers next to the DSP in the center section.  Clearly labeled and my M7 looks exactly like the photo when facing the front of the unit.  Just place a 0.1" (2.54mm) jumper on the two pins labeled PLLEN to bypass the PLL.

 

Also at the AGD link an explanation of the jumper settings.  It looks like you can get 1X sampling, ISP0 jumpered (ON), ISP1 left open (OFF), but the filters seem to be always engaged at either -130dB, -90dB, or -50dB.

 

post #2321 of 3640
Quote:
Originally Posted by ciphercomplete View Post

I think I am going to leave the PLL option off. When I first bypassed PLL the bass sounded lighter to me and I thought that may have been the result of increased jitter. But after further listening the other hallmarks of increased jitter (tinny treble, thin untextured midrange) never reared their heads. The bass is more detailed and palpable and the midrange cleared up some while at the same time seems to have more body. biggrin.gif

I think if you have a good usb to I2S like the Offramp or Transient or others that use really good clocks, you will probably like what you hear with PLL turned off.


I'm in the same camp.  The PLL stays bypassed for a long while at least with the Off Ramp 5 HDMI I2S source.   It is not an overly dramatic change but I am hearing all good things after lengthy listening.  PRaT is better but the sound is more relaxed somehow and seems to flow without much effort.   More high level detail meaning less congestion on loud passages.   Easier to pick out instruments and their location in the mix.  Bass is very good with nice weight and again easier to pick out of the mix.  Highs like cymbals, bells, and vocal silibance are very palpable.  Violins, vocals, and electric guitars have more meat (harmonic detail).  Low level detail/ background seem OK as well but harder to tell with speakers.  Overall sound is warm, comforting, and organic.

 

So I am not finding any negatives of bypassing the PLL and chalking up quite a list of positives.  You are correct that users may have differing experiences depending upon the jitter of their sources.  But it is an easy change to bypass the PLL and decide for yourself.

post #2322 of 3640

@DACLadder & ciphercomplete:

 

Are you leaving your oversampling engaged (8x default) with PLL bypassed?


Edited by jacal01 - 12/1/14 at 10:30am
post #2323 of 3640
Other than bypassing PLL I left everything stock so it still has 8x oversampling engaged.
post #2324 of 3640

Krewl.  Just ordered me some board header jumper cap connectors.

post #2325 of 3640
Quote:
Originally Posted by jacal01 View Post
 

@DACLadder & ciphercomplete:

 

Are you leaving your oversampling engaged (8x default) with PLL bypassed?


Likewise PLL bypass only at this time.   

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