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post #961 of 1957
Quote:
Originally Posted by thegrobe View Post


I've reinstalled my audio-gd drivers, software etc. But still get mysterious stoppages using jriver kernel streaming or ASIO. Maybe it's a problem with jriver? MOG streaming out to USB32 works flawlessly. Anyway still trying to get it working reliably.

That's weird. I use J River as well. Kernel streaming has always worked for me no matter what firmware I had installed. But since the last firmware update wasapi drops out for me. I have only gotten asio to work with firmware #7.
post #962 of 1957
Short answer
Outlet strips or sure protectors protect your investment and nothing more
Conditioners are far more complex. They fall into three catGories.
ISO trans former. Regulates spikes and some noise in the line
Power regeneration creates pure Ac power from transistors the Ac is converted to Dc and then
Back to Ac pure clean power
Last is various amounts of both one and two.

My thoughts are good for front ends dacs pre players CPU. No need for amps for speakers but good for headphone amps

To some extent it is pride of ownership. He's more for poorly designed psu circuits or very sensitive equipment

This is my take on it

Al D
post #963 of 1957
Quote:
Originally Posted by DACLadder View Post
 

I'll check it out, thanks.  Kingwa responded to my Email about the DSP board's I2S header connector pinouts, connector pin pitch, and location of termination resistors.

 

The termination resistors for the external I2S RJ45 are located on the RJ45 connector circuit board mounted to the backplate.  So if the  RJ45 board is removed termination needs to be provided.  I am referring to an OR5 type cable implementation.  A substitute USB receiver board may need something totally different.

 

The pitch (distance) between I2S header pins is 2.54mm (0.1").   This eliminates a lot of guessing for finding header mating connectors.

 

The DSP board I2S header connector pinouts when facing the Master 7 front, left to right, are the following:

 

Pin 1 -  GND

Pin 2 -  SDATA

Pin 3 -  SCLK

Pin 4 -  WCLK

Pin 5 -  MCLK

 

I need to get an oscilloscope on the current RJ45 I2S implementation.  If the clocks look OK at destination then all this extra work is not necessary.   That should happen in the next few weeks.

Hi Dacladder! I am a little bit confused about termination resistors. How do you calculate its proper values??. If you look carefully at the USB32 you can also see 4 termination resistors. I imagine these values are calculated according to M7 I2S pins input impedance. If you change RJ45 or USB board, which is the way to know if more resistors need to be added??

 

Would you please share your opinion??

 

Thanks a lot,

JM


Edited by jmmbarco - 11/19/13 at 2:02am
post #964 of 1957
Quote:

Hi Dacladder! I am a little bit confused about termination resistors. How do you calculate its proper values??

That is a really good question and without a published I2S cable delivery standard each device could be something different.  But the Off Ramp 5 is setup for 120 ohm output impedance and is expecting each of the four cable signals to be terminated with 120 ohms to ground.  I have read references for other products and they use 120 ohms as well.  So 120 ohms seems to be the de facto termination value for single ended, external I2S cabling by design.

 

I would ask Kingwa about the USB I2S output to the DSP board.  He could use something different (or nothing at all) on this short USB board interface between the backplate and DSP board.  With a substitute USB board if you have a schematic of the I2S output we can have a look and make suggestions.  If I were doing this I would use an oscilloscope to tune the I2S signals for best shape at the destination on the DSP board.  That is the only way you know for sure until proven what works best and what does not.  I will have more answers when I pull apart the Master 7 and have a closer look.


Edited by DACLadder - 11/19/13 at 7:05am
post #965 of 1957

Many months ago I read about the steps taken to upgrade the Ref. 7.1 to Master 7.  I am interested in the part about removing the top of the Master 7.   In the upgrade process there were top fasteners to avoid as they are for looks only.  I was thinking it was Currawong's detailed description of the upgrade process but could be wrong.   Anyway, I can't find the article.  Anyone know which Master 7 top fasteners to avoid and which to remove to take the top off?

post #966 of 1957
Thread Starter 
Quote:
Originally Posted by DACLadder View Post
 

Many months ago I read about the steps taken to upgrade the Ref. 7.1 to Master 7.  I am interested in the part about removing the top of the Master 7.   In the upgrade process there were top fasteners to avoid as they are for looks only.  I was thinking it was Currawong's detailed description of the upgrade process but could be wrong.   Anyway, I can't find the article.  Anyone know which Master 7 top fasteners to avoid and which to remove to take the top off?

 

You will need to remove all screws on the top to remove the top lid of the Ref 7.1.

post #967 of 1957
Quote:

You will need to remove all screws on the top to remove the top lid of the Ref 7.1.

Thank you.  The four corner screws plus the four philips screws near the center.

post #968 of 1957

My AP+PP finally arrived (all the way from a fellow headfier in Vietnam).

 

I listened to alot of music last night.  IMO the AP+PP into input 1 is better than the USB32 or the other spdif inputs.  The AP on any other input other than #1 equals the USB32 but of course in this scenario the AP is at a disadvantage.   The AP on input 1 seems to sharpen the focus of everything.  There are no real tonal differences between the AP and USB32, everything is just less fuzzy and warm with the AP. 

 

I listened to a wide variety of music, many different genres with widely varying audio quality.  With high quality/highly dynamic source recordings I heard very little difference between the AP and the USB32.  So for those of us who only listen to highly dynamic recordings  like Eva Cassidy and Chuck Brown's "The Other Side" http://www.dr.loudness-war.info/details.php?id=3559 or Muddy Waters' "Folk Singer" http://www.dr.loudness-war.info/details.php?id=20945 don't bother trying to do better than the USB32 unless you can hear the proposed replacement for free before deciding.  I'm not quite sure why this is the case but great recordings can often make lesser equipment sound great and anyone who has been to a commercial audio show where exhibitors refuse to play anything other than awesomely recorded classical music probably already knew that.  This may be what is going on with the USB32.    

 

 If you have had a chance to compare two different versions of the same album say the mediocre cd version of Wayne Shorter's "Speak No Evil (rvg edition)" and the highly dynamic HD Tracks version, the main thing you will hear is a difference in soundstage depth.  I'm convinced that soundstage depth in recordings is dependent on that recording's dynamic range.  The low volume details and cues are drowned out on low dynamic range recordings which make the music sound as if it is more forward or flatter while highly dynamic recordings provide depth and space.  I am a Dr Database nut and so far my little observation has held up each time I compare different versions of recordings.    

 

So difference wise, the rubber met the road when I listened to less dynamic and average to terribly recorded source material.  Input 1 with the AP does wonders here and the differences are immediately apparent.  The AP on input 1 has this awesome ability to somewhat draw out those low volume details and music cues that give stereo music the illusion of soundstage depth on very bad recordings.  A comparison of the terribly mastered Adele's "21"   http://www.dr.loudness-war.info/details.php?id=7674 which may be the worst recording I own.  It was no contest, the AP offered a deeper listen and details are sharpened without becoming overbearing.  "21" does not become great or even good but it is substantially better via input 1.  Its not that the USB32 is less detailed its just that its warmer sound hurts its ability when it comes to soundstage depth on these types of recordings.  The improvement is significant, the AP on input 1 is not adding any color it just seems to handle compressed music better.

 

The bummer here is that I am not sure if I am comparing the AP to the USB32 or if I am comparing the BNC input to the USB32.  My cd player when used as a transport on input #1 is better than the USB32 but not as good as the AP.  I have a old audio gd DI-V3 that I may try on the BNC input in order to compare it to the internal USB32.  I suspect that I fried my DI-V3's firmware though so don't hold your breath waiting for that comparison.  

 

Too bad there isn't a I2S version of the AP.  :(    


Edited by ciphercomplete - 11/24/13 at 8:52am
post #969 of 1957
Cipher- thanks for the detailed observations. I can certainly agree, what you are hearing is exactly what I've found comparing USB32 and AP2+PP over the last couple weeks. Even the point about the difference being larger on "average" recordings. Although my DAC it's the SA-2, the inputs and DSP version, etc is identical to the M7.

I hadn't thought of or noticed any correlation between DR and soundstage depth, very interesting. I'll have to, in future listening, note the DR on tracks that are especially good or bad in that regard and see...

I certainly hope that Philip at Audiophilleo would consider i2s output in a future version of the converter, that would be a great upgrade.
post #970 of 1957
Quote:

Too bad there isn't a I2S version of the AP

I recently asked Philip G. at Audiophilleo if he plans to offer I2S which seems like a natural progression of the product line.  He said "no" as it would be a total redesign, little marketing demand, and no formal standard for external I2S.

 

Quote:

 IMO the AP+PP into input 1 is better than the USB32 or the other spdif inputs.

Same here... The AP + PP is very engaging on Input 1.  Sounds really good with Redbook 44.1/16 CD format for some reason.

 

My I2S cable/ OR5 experiments are progressing.  Yesterday built a 4 in. cable from CAT 7 (individually shielded pairs).  It is the best sounding of all cables built so far (12", 6", and 3" CAT5,  SATA cable).   Thanksgiving holiday weekend I plan on opening up the Master 7 and putting an oscilloscope to the various cables to perhaps see why one cable may sound better than another.  I also plan to bypass the Master 7 RJ45 jack/ internal ribbon cable and directly connect from OR5 to the M7 DSP board.  I'll post some clock waveforms when complete.

post #971 of 1957
Steve said the one I bought is the sweet spot. And that longer is not advised but there is a method like 2 ft and five feet. Something like that. I can measure what I have if you wish.

Mine is cat7 shielded. Even the connectors are shielded. But the sockets are not. I can post a pic as well if you need ..

Al D
post #972 of 1957

Presumably a scope should be able to pick up any differences in signal reflections, being the designer my guess is that Steve should know the signal rise time and therefore what lengths of a standard RJ45 cable are optimal.  From experience though, the propagation delay of the cable makes a significant difference - if you really want to avoid signal reflections you must know the propagation delay of the cable you are using as this can make all the difference.  The "sweet spot" with one cable might be the worst possible scenario with another cable.

post #973 of 1957
Wow this is complex to plan out then. . I'm glad I bought the cable then lol. I do follow why though I just do not have the time to play in this like that , and as I'm understanding I still am missing the method to accomplish the task.

Al D
post #974 of 1957
Audio gd NFB 7.32. Compared to master 7.

Can someone here explain the difference between the two dacs. I own the master 7. But I read and a lot have the other dac just wondering the difference in sound .

Thanks
Al D
post #975 of 1957

Not sure many people heard both in good condition (e.g. at home, for an extended time even though the difference should be noticeable quite easily).

The units were stacked up in the recent San Diego Meet with ohhgourami's Krell + HE-6 setup (I think he owns the NFB-7 and Purrin brought the M7). You might find some information on that in the SD meet thread.

 

My take on the subject - having not heard the M7 - but owned the Reference 5.32, NFB-27 and SA-1.32 (in that order) is that they both share a similar tonality which is a shift towards brighter sound signature when compared to the typical A-GD's PCM1704 sound in the Reference line (which, IMO, is dark sounding).

 

The biggest difference should be the mids. While all the TOTL designs from Kingwa have a nice organic tone (slightly warm and lots of meat on the bones), the R2R design sound more like "the real thing". It's more fluid and the bass-mid-treble integration seem more coherent. The mids of the R2R is lusher and fuller (even more meat on the bone).

 

The Sabre should have slightly more pronounced treble (probably not more refined, just more presence there) and more articulation. The imaging might be slightly sharper as a result (better? I don't think so).

 

I'm currently shopping for a M7 (still debating between it and getting another Eximus DP1). If I end up buying one, these assumptions would become real impressions.


Edited by Clemmaster - 11/25/13 at 6:08pm
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