[Currawong]

I used a long wire!

Seriously is that a sine wave? Look corrupt and definitely a lot of aliasing. Which DAC is it?

A much older Master 7. This is the normal aliasing you get with no oversampling from a NOS DAC. I think the reason that a lot of people like NOS DACs is the result of the stock filters on modern DS DACs being so horrid.

 

[Articnoise]

I used a long wire!



A much older Master 7. This is the normal aliasing you get with no oversampling from a NOS DAC. I think the reason that a lot of people like NOS DACs is the result of the stock filters on modern DS DACs being so horrid.

Lol, if you consider the old Master 7 a NOS DAC it explain a lot.

The digital filter in the Master 7 was nothing to write home about IMO. I got the best sound then used as little filtering as possible, which was with 2x oversample and 90dB stopband. With the stopband at 50dB the image got smeared, the overall sound got less coherent and some artifact in the treble made it fatigue to listen to. The 50dB filter was more resolving thou.

Not to argue, but can you name some modern DS DACs in the M-7 to R2R-7 price range that have stock filters on modern DS DAC that you have thought sound horrid.

 

[Currawong]

About the modern DS DACs, indeed!

The measurements were using the M7 is NOS mode. If my scope wasn't dead, I'd measure it again, but the aliasing is typical of NOS DACs for playback of 44.1 material. Only oversampling, up-sampling or high-res music will remove it.

 

[FredA]

I agree with Currawong. In its basic form, nos will produce low level signals with visible aliasing. At -80db, it should be very obvious. Unless the analog filter does miracles, which i doubt. NOS with low res formats will also produce a rolled off treble unless you compensate it somehow. For me, the OS (or upsampling) algorithms are key today to get quality sound reproduction. A bad implementation of OS can sound artificial or harsh however. Nos will not sound harsh in general or artificial. The overall filtering aspect and jitter management are the biggest challenges these days.

 

[FredA]

Tonight, i turned software upsamping off, still in NOS 3 mode. With records that have not much dynamics perhaps even in the original master, like some old jazz records, the sound lacks punch, although it is still very natural and with a very good soundstage, meaning the highs are still excellent, which is a nice surprise. I don't know what magic trick is used to avoid the rolled off treble, but it works. Anyone has a clue on this?

With more recent and punchy recordings, i can say there is adequate punch in the sound. Also, in favor of nos 3, i can say it produces a bass i like very much, plus a laid back sound. Nos is definitely more analogue in average. The r2r 7 in nos 3 seems to produce a more consistent sound from one day to the other. At this point, i can't say which i prefer begween OS or NOS (mode 3). Depends on which record i listen to, i suppose. I think it's well worth trying if your digital source is excellent. You might be surprised and prefer it. I like it more and more with time.

Now listening To Herbie Hancock, Head Hunters. Nice overall presentation and dynamics, very enjoyable. Very tight bass. Very natural and easy on the ears. Very detailed as well. Excellent rythm.

 

[Currawong]

What has been interesting to hear is how little dramatic difference there is between the regular 8x oversampling mode and NOS mode with the accurate firmware. There isn't the dramatic change in imaging that I remember getting with the older Audio-gd DACs. Sure, instruments become smoother and slightly more vague, but not by a large degree. This with high-quality 44.1 instrumental tracks from Michael Hedges.

 

[FredA]

What has been interesting to hear is how little dramatic difference there is between the regular 8x oversampling mode and NOS mode with the accurate firmware. There isn't the dramatic change in imaging that I remember getting with the older Audio-gd DACs. Sure, instruments become smoother and slightly more vague, but not by a large degree. This with high-quality 44.1 instrumental tracks from Michael Hedges.

Great. I am gonna give the accurate firmware a try.

 

[christianvogel]

6Moons review: http://www.6moons.com/audioreviews2/audio-gd/1.html

 

[christianvogel]

Point of interest: The 6Moons reviewers preferred DIP setting to OS mode x1 (S2 off, IPS0, IPS1 on), and also ATT0 and ATT1 on!

I checked with Magna Hifi, ATT0 and ATT1 set the filter steepness. Both off gives a 130db filter, either on gives a 90Db if I remember correctly. Both on... was is 150db? I am not sure. I will check. Pure NOS mode has no filter applied. NOS mode does have a -6Db high filter, boosting the high frequencies to compensate for the normal NOS 6db drop in high frequencies.

In any case, this opens up some experimenting.

 

[gk2013]

Blue Moon Award !

 

[christianvogel]

Blue Moon Award !

Oh yes, forgot to mention that :-D

 

[barbas]

Point of interest: The 6Moons reviewers preferred DIP setting to OS mode x1 (S2 off, IPS0, IPS1 on), and also ATT0 and ATT1 on!

I checked with Magna Hifi, ATT0 and ATT1 set the filter steepness. Both off gives a 130db filter, either on gives a 90Db if I remember correctly. Both on... was is 150db? I am not sure. I will check. Pure NOS mode has no filter applied. NOS mode does have a -6Db high filter, boosting the high frequencies to compensate for the normal NOS 6db drop in high frequencies.

In any case, this opens up some experimenting.

The settings used are really weird, at least. No mention if S2 is ON or OFF. In case S2 is OFF (OS mode, with IPS0 and IPS1 ON, meaning NOS with digital filter) ATT0 and ATT1 should make no difference as they are marked RESERVED. With S2 ON (NOS mode 1, analog filter) IPS0 and IPS1 in this case should not alter anything wether ON or OFF.

 

[christianvogel]

The settings used are really weird, at least. No mention if S2 is ON or OFF. In case S2 is OFF (OS mode, with IPS0 and IPS1 ON, meaning NOS with digital filter) ATT0 and ATT1 should make no difference as they are marked RESERVED. With S2 ON (NOS mode 1, analog filter) IPS0 and IPS1 in this case should not alter anything wether ON or OFF.

I suspect this has changed with the firmware upgrade, and these are probably things Kingwa plays with for his own testing (thus reserved).

It is mentioned in the review that all other jumpers (including S2) were off. Independently this setting was also suggested to me to test by Magna hifi (who were in contact with 6Moons for this review).

 

[barbas]

I suspect this has changed with the firmware upgrade, and these are probably things Kingwa plays with for his own testing (thus reserved).

It is mentioned in the review that all other jumpers (including S2) were off. Independently this setting was also suggested to me to test by Magna hifi (who were in contact with 6Moons for this review).

Got it...so, with standard 'smooth' firmware ATT0 and ATT1 will modify filter steepness? Both ON would set it to -90db? An this is the settings Jos recommended you to try?

 

[FredA]

This review is very confusing, as often, I find, with 6-moon. It seems like it's been done in a hurry.