[thecrow]

Hi Everyone,

What streamers are you using with your Holo May, especially if you are using the streamer with the May with its PLL turned off?

And how is it working out for you?

Thanks

Aries g2.1

happy with it - but nothing to compare it with.

one of its strengths is its wifi capability/quality. That was a very crucial factor for me.

prices went up in the last six months or so so keep that in mind if looking at prices of second hand or older (new) stock in store - there may be margin to play with for the seller vs new rrp

 

[Zachik]

How does that streamer compare to other options you've tried?

Only other source I use is a fanless NUC based PC. Not the Roon server that they sell, but the hardware is quite similar inside.
The Mercury streamer is as good (or slightly better) to my ears, and much cheaper...

What power supply are you using with it?

The stock power brick. I have not experimented with LPS, yet.

I see that are sold out...making more?

Yes, they hit supply chain snag, and working towards making more in a couple months...

 

[ExtremeBoky]

The PC-based streamers require a very low noise power supply. This is absolutely crucial, especially if you use USB to connect the streamer and May.

 

[gk2013]

The PC-based streamers require a very low noise power supply. This is absolutely crucial, especially if you use USB to connect the streamer and May.

Or you can use i2s and use a SU6 in between the Holo May and the PC based streamer. This is really good!

 

[zoidbb]

The PC-based streamers require a very low noise power supply. This is absolutely crucial, especially if you use USB to connect the streamer and May.

Absolutely untrue. The May uses opto-isolators to keep any USB-sourced noise /out/ of the DAC. Your streamer could have ridiculously noisy power and it wouldn't impact May at all.

 

[ExtremeBoky]

The USB module (card) inside May is powered by the streamer.

 

[zoidbb]

The USB module (card) inside May is powered by the streamer.

I invite you to look at this image: https://www.kitsunehifi.com/wp-content/uploads/2020/02/May-Dac14.jpg
Note how next to the connector which connectors to the DAC "motherboard", there are two opto-isolaters. There's also a significant air gap between the USB-powered board and the connector. This means that the DAC is completely isolated from any noise, power or otherwise, coming from the USB source. It doesn't matter that the components ACROSS that air-gap are powered by the streamer, because that circuit only exists to accept the incoming USB, decode it, and yeet it safely into the rest of the DAC.

 

[ExtremeBoky]

The USB module is also sensitive to noise. Its ground fill is incapable of dealing with noise due to vey small ground fill area. A very low impedance power supply ( at broad frequency spectrum, in particular in case of a DAC that can support 1,536/1024) is required to be able to deal with large number of switching gates, that switch at very fast rates. The common return point for that noise is back at the USB host source of Vbb inside the streamer.

The ground isolation works only if the Vcc coming from the streamer via USB cable is properly taken care of: the Vcc needs to be of a very low noose and impedance, the USB cable must take into consideration the above as well. This is why the split USB cables, that use separate low impedance path for USB card Vbus, sound the best.

Also, the streamers that sound really good routinely utilise a very low noise linear regulators like 3045, just to generate low noise Vbus for Mays USB card.

The USB card in itself contains a very large number of switching ICs. May’s designer did a good job in trying to combat the noise; there are aproximatly 10 local regulators (prety much every IC voltage pin has its own regulator); but the most important thing is actually how clean that Vbus is and how good the USB cable is with regard to feeding the Vbus to USB module via low impedance path. A lot of braid and large soldering area at both ends of the cable are crutial as well.

The PLL is always on for USB; however, the USB card must have a very low noise Vbus because it is most compromised section in a DAC… why? Because by design, the galvanic isolation is introduced to combat exactly what you are proposing: that the Vbus is not important. So, that misconception is combat to a certain degree by isolation; however., a new issue arises as the result - a compromised ground fill area… that requires a very low noise Vbus. AND a very low impedance USB cable, so that the noise can find the common return for that noise, which is all the way back…inside the streamer.

 

[zoidbb]

The USB module is also sensitive to noise. Its ground fill is incapable of dealing with noise due to vey small ground fill area. A very low impedance power supply ( at broad frequency spectrum, in particular in case of a DAC that can support 1,536/1024) is required to be able to deal with large number of switching gates, that switch at very fast rates. The common return point for that noise is back at the USB host source of Vbb inside the streamer.

The ground isolation works only if the Vcc coming from the streamer via USB cable is properly taken care of: the Vcc needs to be of a very low noose and impedance, the USB cable must take into consideration the above as well. This is why the split USB cables, that use separate low impedance path for USB card Vbus, sound the best.

Also, the streamers that sound really good routinely utilise a very low noise linear regulators like 3045, just to generate low noise Vbus for Mays USB card.

The USB card in itself contains a very large number of switching ICs. May’s designer did a good job in trying to combat the noise; there are aproximatly 10 local regulators (prety much every IC voltage pin has its own regulator); but the most important thing is actually how clean that Vbus is and how good the USB cable is with regard to feeding the Vbus to USB module via low impedance path. A lot of braid and large soldering area at both ends of the cable are crutial as well.

The PLL is always on for USB; however, the USB card must have a very low noise Vbus because it is most compromised section in a DAC… why? Because by design, the galvanic isolation is introduced to combat exactly what you are proposing: that the Vbus is not important. So, that misconception is combat to a certain degree by isolation; however., a new issue arises as the result - a compromised ground fill area… that requires a very low noise Vbus. AND a very low impedance USB cable, so that the noise can find the common return for that noise, which is all the way back…inside the streamer.

The USB module doesn't give a crap about the noise so long as the signal is far enough above that it can still decode the signal. And that works just fine, or you'd be losing connectivity /constantly/. USB transmission rates don't change at all based on the sample rate of the inbound signal -- its all just bits being sent at the same speed over the same link. Really doesn't matter unless the noise gets INTO THE DAC, which it doesn't.

I don't know why you're talking about ground isolation. There's no "ground isolation" here. There's galvanic isolation. That is to say, the USB circuit is electrically separate from the rest of the DAC. There is NO shared ground between the USB input module and the remainder of the DAC, nor is there any other shared electrical circuit.

Your last paragraph is... incoherent and incomprehensible.

 

[ExtremeBoky]

Yeah, I thought so... trying too hard

Maybe the below will make more sense... choose to read it, or ignore it....

The ground isolation was introduced due to the neglect that, in true honesty -> you are encouraging here, by saying that "The USB module doesn't give a crap about the noise so long as the signal is far enough above that it can still decode the signal".

This necessity of ground isolation creates a monster - a very small & isolated USB module ground fill that is highly susceptible to noise - it virtually can not handle the noise - it can not get rid of it... A very large number of LDOs (voltage regulators, for each IC Vcc pin - best in the industry!!!) is introduced on May's USB module. These LDOs work to a degree... they try to isolate intermodulation/noise between various ICs placed on that USB module (segregating the noise between ICs), but they are (LDOs) NOT EFFICIENT in coupling the circulating noise from that small ground fill to the Vbus common. This noise can not be coupled to May's main board common due to isolation (galvanic isolation, which is ground fill isolation between USB ground and May DAC ground)

The only way the USB ground fill can handle the noise is if it is drained from that ground fill. The only path is via a very low noise and low impedance Vbus circuit. USB cable is an integral part of that circuit; it is an extension of that USB module ground fill. Hence, it has to have a very low impedance path between the Vbus source (steamer) and the May DAC module source of the noise. The noise is drained via a USB cable shield, but also via a Vbus cable - due to a very low noise/impedance Vbus at the source/streamer - it's like the Vbus and the ground at the streamer-end are sitting at the same virtual potential for AC (HF noise). Now, remember your statement: "The USB module doesn't give a crap about the noise so long as the signal is far enough above that it can still decode the signal".

The noise circulating that USB card can be ISOLATED from entering the May DAC main board; HOWEVER, it will still cause havoc to the sound being processed on that USB module itself if care is not taken. This is where we disagree - you think that the noise is not important here.

The designers did their bit - a large number of LDOs (which still can not couple the noise to Vbus common point of return). The user has to have a good understanding of the above and take it from LDOs a few steps further: use very low noise (usually linear) power supplies to power the streamer, use good streamers that have a separate voltage regulator to generate low noise/impedance Vbus for USB card, and use high-quality USB cables. The focus here with USB cables is not on differential pair USB + and - digital signal.... the focus is on the amount of shield and Vbus cable thickness/quality (+ the soldering of those large shield & Vbus cables to those little USB connector pins).

 

[zoidbb]

Yeah, I thought so... trying too hard

Maybe the below will make more sense... choose to read it, or ignore it....

The ground isolation was introduced due to the neglect that, in true honesty -> you are encouraging here, by saying that "The USB module doesn't give a crap about the noise so long as the signal is far enough above that it can still decode the signal".

This necessity of ground isolation creates a monster - a very small & isolated USB module ground fill that is highly susceptible to noise - it virtually can not handle the noise - it can not get rid of it... A very large number of LDOs (voltage regulators, for each IC Vcc pin - best in the industry!!!) is introduced on May's USB module. These LDOs work to a degree... they try to isolate intermodulation/noise between various ICs placed on that USB module (segregating the noise between ICs), but they are (LDOs) NOT EFFICIENT in coupling the circulating noise from that small ground fill to the Vbus common. This noise can not be coupled to May's main board common due to isolation (galvanic isolation, which is ground fill isolation between USB ground and May DAC ground)

The only way the USB ground fill can handle the noise is if it is drained from that ground fill. The only path is via a very low noise and low impedance Vbus circuit. USB cable is an integral part of that circuit; it is an extension of that USB module ground fill. Hence, it has to have a very low impedance path between the Vbus source (steamer) and the May DAC module source of the noise. The noise is drained via a USB cable shield, but also via a Vbus cable - due to a very low noise/impedance Vbus at the source/streamer - it's like the Vbus and the ground at the streamer-end are sitting at the same virtual potential for AC (HF noise). Now, remember your statement: "The USB module doesn't give a crap about the noise so long as the signal is far enough above that it can still decode the signal".

The noise circulating that USB card can be ISOLATED from entering the May DAC main board; HOWEVER, it will still cause havoc to the sound being processed on that USB module itself if care is not taken. This is where we disagree - you think that the noise is not important here.

The designers did their bit - a large number of LDOs (which still can not couple the noise to Vbus common point of return). The user has to have a good understanding of the above and take it from LDOs a few steps further: use very low noise (usually linear) power supplies to power the streamer, use good streamers that have a separate voltage regulator to generate low noise/impedance Vbus for USB card, and use high-quality USB cables. The focus here with USB cables is not on differential pair USB + and - digital signal.... the focus is on the amount of shield and Vbus cable thickness/quality (+ the soldering of those large shield & Vbus cables to those little USB connector pins).

I would agree with you if you were even remotely correct, however if you look at the USB module... it's grounded... to the chassis

Also there's no "sound being processed on the USB module" -- Those are optoisolators are sending a DIGITAL audio signal across the gap. No amount of noise on the USB module side is going to make a damn bit of difference, even if it didn't get "drained" (poor term btw, since you shouldn't have significant capacitance in your grounding system).

 

[ExtremeBoky]

I would agree with you if you were even remotely correct, however if you look at the USB module... it's grounded... to the chassis

Haha, you are good!!

Ignorance is bliss. Did you try to confirm that rubbish of yours you have posted... and have been posting for a while?

 

[zoidbb]

...Friend, I posted a picture of the board where you can /quite/ clearly see where the PCB is grounded to the chassis... as it should be...

 

[ExtremeBoky]

It is NOT grounded to the chassis. I KNOW!!! I've been modifying the old Mays USB modules. Do you even have May DAC???

 

[zoidbb]

Yes. Do me a favor, since you mod Mays go crack one along your multimeter and test it. Send a video.