HOLO Audio MAY DAC

[mushi]

On 10/16/2020 at 4:37 AM, Diavolo said:

I had locking and intermittent audio drop out with my nvidia shield sending audio through my Samsung HDTV via Toslink.  I simply enable PCM Oversampling on the May when I watch things on the Shield.

Damn it, just now I checked that the SPDIF locking only occurs in NOS mode!!!

PLL on OS/OS PCM/OS DSD mode works fine.

 

Can anyone explain it to me technically? My support from MagnaHiFi can only copy/paste information from the KitsuneHiFi home page..

[mushi]

UPDATE

 

I think we have found first scratch on HoloAudio marvelous reputation.

 

On 10/8/2020 at 11:28 PM, GoldenOne said:

@mushido you have a pc with optical output you can try? If that does not work with pll then you know its the dac.

 

If it does, you know it's the minidsp

 

I just bought a digital tuner and connected it to May through SPDIF Coax, and guess what? It's LOCKING!!!

It looks like there is malfunction PLL and NOS mode with SPDIF signal (OS/OS PCM/OS DSD mode works fine).

 

On 10/8/2020 at 4:36 PM, barrows said:

This confirms that the mini DSP has too much jitter.  When you turn off the PLL of the May, then all the jitter from the mini DSP goes right on through to the output of the DAC, and you are not getting the sound quality that you paid for.  Time to ditch the mini DSP if you want to achieve the sound quality which the May DAC is capable of. 

 

Through this time I contacted with miniDSP support team, and guys took this problem seriously:

- miniDSP engineers put the SHD Studio on the APX555x to check the locking and metadata and everything seems fine. The metadata for SPDIF/AES-EBU is indeed correct.

- FYI, their device always outputs the clock actually. No matter if muted/paused, it's always outputting the clocking+metadata.

 

And now best thing:

- when miniDSP engineers are asking for more details on the metadata which HoloAudio expect, and are asking about more details of HoloAudio clocking circuit (the one that shows an unlock), MagnaHiFi doesn't know the answer or copy/paste marketing blurp about PLL circuit from KitsuneHiFi homepage, but Tom from KitsuneHiFi gave me better answer: turn off PLL. Thats all.

 

HoloAudio claim (from KitsuneHiFi homepage) that:

"A common technique to improve the clock signal from SPDIF is PLL."

and

"Now the May is implemented with femto clocks, and also new discrete ultra high performance voltage regulators. It has an advanced PLL (phase lock loop) circuit that is completely custom built for ultra high performance anti jitter performance. Even the highest levels of jitter are near eliminated which delivers world class performance."

 

Why should I turn off the PLL? In order to degrade the sound quality?

What is the PLL installed there for? Just for looks?  Such a marketing trick to make more audiophiles buy this device?

 

And my problem is that I am not able to convince myself of it's spectacular performance because it does not work..

 

 

What do you think guys?

 

 

 

[John Hughes]

So, I've made the leap and ordered a Holo May KTE edition :)

[barrows]

30 minutes ago, mushi said:

UPDATE

 

I think we have found first scratch on HoloAudio marvelous reputation.

 

 

I just bought a digital tuner and connected it to May through SPDIF Coax, and guess what? It's LOCKING!!!

It looks like there is malfunction PLL and NOS mode with SPDIF signal (OS/OS PCM/OS DSD mode works fine).

 

 

Through this time I contacted with miniDSP support team, and guys took this problem seriously:

- miniDSP engineers put the SHD Studio on the APX555x to check the locking and metadata and everything seems fine. The metadata for SPDIF/AES-EBU is indeed correct.

- FYI, their device always outputs the clock actually. No matter if muted/paused, it's always outputting the clocking+metadata.

 

And now best thing:

- when miniDSP engineers are asking for more details on the metadata which HoloAudio expect, and are asking about more details of HoloAudio clocking circuit (the one that shows an unlock), MagnaHiFi doesn't know the answer or copy/paste marketing blurp about PLL circuit from KitsuneHiFi homepage, but Tom from KitsuneHiFi gave me better answer: turn off PLL. Thats all.

 

HoloAudio claim (from KitsuneHiFi homepage) that:

"A common technique to improve the clock signal from SPDIF is PLL."

and

"Now the May is implemented with femto clocks, and also new discrete ultra high performance voltage regulators. It has an advanced PLL (phase lock loop) circuit that is completely custom built for ultra high performance anti jitter performance. Even the highest levels of jitter are near eliminated which delivers world class performance."

 

Why should I turn off the PLL? In order to degrade the sound quality?

What is the PLL installed there for? Just for looks?  Such a marketing trick to make more audiophiles buy this device?

 

And my problem is that I am not able to convince myself of it's spectacular performance because it does not work..

 

 

What do you think guys?

 

 

 

A PLL has a kind if window function, and the opening of that window can be wide, or it can be narrow.  A very wide window will be able to lock to high jitter streams coming in, and a very narrow window will require a lower jitter signal to begin with.  For example, the ESS 9038 DAC chip has an onboard PLL, with an adjustable input "window", when you adjust the window to its lowest opening, the DAC will not lock to some (higher jitter) sources, and the solution is to either open the window a bit, or reduce the jitter of the source.  Opening the window a little wider is a compromise, because it will let more of the source jitter through.  The best solution is to reduce the source jitter.

Sounds like the Holo Audio May has a fairly narrow window in its PLL circuit, so one may need to deactivate the PLL for some high jitter sources-If this is what is happening, then one cannot blame Holo Audio because their source has too much jitter, the source is the problem, and Holo audio can accommodate that source by turning off the PLL.

 

Alternatively, it is possible your specific May has a problem with its PLL circuit, but I have not heard any evidence which suggests strongly that is the case here, still could be though...

[mushi]

4 minutes ago, barrows said:

A PLL has a kind if window function, and the opening of that window can be wide, or it can be narrow.  A very wide window will be able to lock to high jitter streams coming in, and a very narrow window will require a lower jitter signal to begin with.  For example, the ESS 9038 DAC chip has an onboard PLL, with an adjustable input "window", when you adjust the window to its lowest opening, the DAC will not lock to some (higher jitter) sources, and the solution is to either open the window a bit, or reduce the jitter of the source.  Opening the window a little wider is a compromise, because it will let more of the source jitter through.  The best solution is to reduce the source jitter.

Sounds like the Holo Audio May has a fairly narrow window in its PLL circuit, so one may need to deactivate the PLL for some high jitter sources-If this is what is happening, then one cannot blame Holo Audio because their source has too much jitter, the source is the problem, and Holo audio can accommodate that source by turning off the PLL.

 

Alternatively, it is possible your specific May has a problem with its PLL circuit, but I have not heard any evidence which suggests strongly thta is the case here, still could be though...

I hear you.

But how do you explain that miniDSP and PLL works together on OS mode but on NOS mode doesn't?

And I'm not the first one, @Diavolo has the same problem with SPDIF.

 

[GoldenOne]

5 minutes ago, mushi said:

I hear you.

But how do you explain that miniDSP and PLL works together on OS mode but on NOS mode doesn't?

And I'm not the first one, @Diavolo has the same problem with SPDIF.

 

The akm oversampling chip functions as something of a clock isolator. A good resource for reading about this is the adi-2 Pro manual, as you can actually use the SRC function in that device to achieve a similar effect beyond the adi-2's steadyclock pll. 

 

Suggesting that the akm oversampling chip output is within the window function of the pll but the raw spdif output of your minidsp is not. Which would further suggest the problem is not the may. The akm chip would be prior to the pll in the signal path. 

 

When you say minidsp put it on the apx555 did they out YOUR one on it? Or just one they had? It's entirely possible that it's just your unit and not the product design itself. A faulty oscillator maybe. 

[barrows]

3 minutes ago, mushi said:

I hear you.

But how do you explain that miniDSP and PLL works together on OS mode but on NOS mode doesn't?

And I'm not the first one, @Diavolo has the same problem with SPDIF.

 

Without knowing more about the exact circuitry of the DAC i could not say, this is a question I would suggest you address to Holo Audio.

[mushi]

17 minutes ago, GoldenOne said:

When you say minidsp put it on the apx555 did they out YOUR one on it? Or just one they had? It's entirely possible that it's just your unit and not the product design itself. A faulty oscillator maybe. 

No, it was one of their devices.

 

miniDSP SPDIF/AES-EBU clock is generated by the SHARC ADSP-21489 + SPDIF/AES-EBU Digital transmitter by AKM. Thats all I know.

 

 

17 minutes ago, barrows said:

Without knowing more about the exact circuitry of the DAC i could not say, this is a question I would suggest you address to Holo Audio.

I did it, and Tim from KitsuneHiFi put me off: turn off PLL, that was all his answer.

 

EDIT:

Thanks for your effort to help guys.

[mushi]

 

1 hour ago, barrows said:

Sounds like the Holo Audio May has a fairly narrow window in its PLL circuit, so one may need to deactivate the PLL for some high jitter sources-If this is what is happening, then one cannot blame Holo Audio because their source has too much jitter, the source is the problem, and Holo audio can accommodate that source by turning off the PLL.

 

What you are saying is in opposite to what is HoloAudio claiming:

 

 

 

 

[GoldenOne]

2 minutes ago, mushi said:

 

 

What you are saying is in opposite to what is HoloAudio claiming:

 

 

 

 

Unfortunately the issue can't really be answered without further testing. 

 

You'd need to try another spdif source, such as a pc. To see if that works with pll. 

 

Or you'd need to do a j-test yourself using the minidsp + pll off but you'd need a decent adc for that. 

 

No one else has encountered this issue so whilst it may be frustrating it really can't be solved without further help. (though I have to say kitsunes customer 'support' is certainly lacking) 

 

Given that it works with the akm chip I imagine the cause is the minidsp. But as said, until you try another source it's all speculation. Easiest thing to do would be grab a USB to spdif DDC, or a hifiberry or something and see if that works. 

[John Hughes]

I received my Holo May KTE dac today.  Set it up and running it in.  Immediately- huge dynamics, more detail, bigger soundstage, bass has more authority, greater separation of instruments than my other dac.   I'll comment more after 200 hours of playing.   Took 1 month to deliver from when I ordered, I was worried it would take a lot longer because of how much good press the May is getting now. 

[Dev]

17 minutes ago, John Hughes said:

I received my Holo May KTE dac today.  Set it up and running it in.  Immediately- huge dynamics, more detail, bigger soundstage, bass has more authority, greater separation of instruments than my other dac.   I'll comment more after 200 hours of playing.   Took 1 month to deliver from when I ordered, I was worried it would take a lot longer because of how much good press the May is getting now. 

can you elaborate what DAC you were using before ? 

[Dev]

I am interested in the May as well. Are folks feeding it with upsampled data to sounds it best ? Can anybody compare between native vs upsampled data ?

[fds]

On both DACs I am using (Chord Mojo, Metric Halo LIO-8) the benefit from upsampling via HQPlayer to the highest possible rates (768kHz/DSD256, 192kHz) is substantial. Here in my system this difference is not subtle but decisive. My favorites are sinc-L and sinc-M since timing seems to be more accurate then with others I have tried. I will be very surprised if the May does not benefit similarly.

 

The OP seems to prefer the May when fed via high rate DSD to using the PCM R2R mode. Requires lots of CPU power but those coming from T+A DAC8DSD should be well prepared since DSD256 and DSD512 seems to be the best feed for this unit as well.

[fds]

Stereophiles Digital Component of the Year 2020 = Holo Audio May L3

https://www.stereophile.com/content/stereophiles-products-2020-digital-component-year

(Wondering whether they had listened to its DSD DAC part with redbook upsampled by HQPlayer as well without telling us?)

[luisma]

3 hours ago, fds said:

(Wondering whether they had listened to its DSD DAC part with redbook upsampled by HQPlayer as well without telling us?)

Have you?

 

I think they are not so much into digital processing with HQP and more into feeding standard redbook and outputting using only the DAC internals, not everyone is a fan of HQP

[luisma]

On 11/17/2020 at 3:41 AM, fds said:

On both DACs I am using (Chord Mojo, Metric Halo LIO-8) the benefit from upsampling via HQPlayer to the highest possible rates (768kHz/DSD256, 192kHz)

I just noticed your previous post, so you do prefer "decisively" DSD over PCM? I'm not trying to be rhetorical just truly curious about your experience.

You using EC modulators?

[luisma]

and for what is worth have you tried the May without using (bypassing) HQP? again I will be delighted to hear your opinion ...

 

[fds]

Hi luisma, unfortunately I did not have access to the May (yet?). 

 

6 minutes ago, luisma said:

so you do prefer "decisively" DSD over PCM?

 

Well I prefer decisively using HQP to upsample to the highest rates my DACs can take as opposed to no software upsampling (or to upsampling via JRMC). In fact, the LIO-8 unfortunately cannot play DSD only PCM. The Mojo can do both but appearantly converts DSD into PCM inside. Here I had once very good results with DSD256 but my current server is not really capable of doing this without problems in real-time. Still PCM 768kHz from HQP with sinc-L sounds wonderful on the Mojo, as does PCM 192kHz from HQP with sinc-L on the LIO-8. Comparing Mojo and LIO-8, the Mojo is a tad cleaner with slightly better timing while the LIO-8 offers more physicality and stucture down low.

 

 

 

 

 

 

 

[fds]

On 9/30/2020 at 3:22 PM, luisma said:

Be aware that after trying HQP this there is no turning back :)

You were absolutely right with this statement in my opinion! :-) Thanks!

[Diavolo]

1 minute ago, luisma said:

Have you?

 

I think they are not so much into digital processing with HQP and more into feeding standard redbook and outputting using only the DAC internals, not everyone is a fan of HQP

I use Roon which is limited to 768khz 32bit pcm. I never thought I'd use hqplayer, but it supports 1.536mhz pcm and allows you to set the word length to 20bit to match the May Dac as well as up to DSD1024, but DSD512 is more realistic as DSD1024 is very processor heavy task. Sounds pretty phenomenal to me in NOS mode on the May Dac to me at 1.536mhz pcm at 20bit. I prefer pcm to dsd, but I'm in the minority. I know of several who prefer DSD upsampling mode.  Hqplayer works well with Roon if they are both on the same media pc.  Remote use of hqplayer on a separate pc with Nvidia Cuda offloading is a bit laggy and not as good imho from a usability standpoint at least with Roon.

It maybe counterintuitive, but using a fairly powerful pc to do the upsampling using hqplayer is far superior to doing it in the DAC, as most don't have the horsepower or available processor heavy filters to chose from.  Ymmv, and I'm sure just sending redbook in NOS mode is also very good sounding as well. Whatever you chose, you won't be disappointed. 

[luisma]

3 minutes ago, fds said:

Hi luisma, unfortunately I did not have access to the May (yet?

Oh I thought you did, ok, don't want to derail the thread just that on my DAC which is the May's competition PCM sounds better (subjectively) that DSD and was wondering if you had the May if that wasn't the case. Thanks

[luisma]

8 minutes ago, Diavolo said:

and allows you to set the word length to 20bit to match the May Dac as well

Sorry for the OT but it related to the May indirectly, and this might bring more traffic to this topic, recent posts from Jussi he has recommended 18 bits LNS for most ladder DAC's, don't know if going from 20 bits to 18 bits will make a huge difference.

10 minutes ago, Diavolo said:

I use Roon which is limited to 768khz 32bit pcm

Me too but I was never a fan of their upsampling

 

11 minutes ago, Diavolo said:

It maybe counterintuitive, but using a fairly powerful pc to do the upsampling using hqplayer is far superior to doing it in the DAC

I kind of agree, let's say 85% with this statement but once I played some files directly (not Roon) to my DAC (not the May but similar) and the sound was incredible without HQP (and without Roon), this was very subjective that's why I asked for all of your opinions regarding this subject.

 

Thank you @Diavolo for posting your opinions +1

 

[fds]

12 minutes ago, Diavolo said:

I use Roon which is limited to 768khz 32bit pcm. I never thought I'd use hqplayer

While Roon seems to be more server-friendly and gives betters results than JRMC here, HQP with sinc-L (or sinc-M) is much better than anything I got with Roon. 

[Diavolo]

2 minutes ago, luisma said:

Sorry for the OT but it related to the May indirectly, and this might bring more traffic to this topic, recent posts from Jussi he has recommended 18 bits LNS for most ladder DAC's, don't know if going from 20 bits to 18 bits will make a huge difference.

Me too but I was never a fan of their upsampling

 

I kind of agree, let's say 85% with this statement but once I played some files directly (not Roon) to my DAC (not the May but similar) and the sound was incredible without HQP (and without Roon), this was very subjective that's why I asked for all of your opinions regarding this subject.

 

Thank you @Diavolo for posting your opinions +1

 

Just a quick note, Jussi advised me to use 20bit for the May KTE DAC. He even recommends Holo NOS DACS (among others). This also applies to the Holo Spring model as well. Best of luck.