[Reactcore]

Good, i have been listening since I was in the crib, so the experience is there. I will listen to the M Scaler out via Toslink vs BNC and see what is the deal.

When on toslink be shure the Dac has all other inputs disconnected

 

[GuiltyRocker]

When on toslink be shure the Dac has all other inputs disconnected

You got it.

 

[musicinmymind]

I have Double Helix Prion4 BNC custom between M Scaler and Dave, which was custom made and cost a bomb, do not want to try toslink to discover it was better, will live with what I have.

 

[Jawed]

In listening tests before with the Poweradd powerbank, using that (with optical) means that you no longer need to worry about the BNC cables - quality BNC sounded the same as Wave Stream. This listening test observation makes sense technically as there is no possibility of Hugo M scaler ground currents flowing into the DAC and out via the mains, thus making the ground plane noisy. And it's ground plane noise in the DAC that gives the mechanism for sound quality changes.

One of the things you've never talked about is a "star" configuration for the ground in your DACs.

I've read this amazing article:

https://www.diyaudio.com/community/threads/audio-component-grounding-and-interconnection.163575/

which very clearly explains how "star earthing" should be done, and this picture from section 4 of the article:

is a very useful point of reference. It appears to show that, when using a rigorous star earthing scheme, a separate ground for the analogue circuitry is immune to digital noise circulating around the loop completed by the digital source (e.g. HMS). So, common mode noise that flows from HMS or another digital source (e.g. over USB) through the digital ground and back to the digital source stays away from the analogue ground.

In both cases the "ground busses" in this picture can be seen as "stars" so that the entire DAC has a "star of stars" configuration.

The key concept here seems to be: you can never stop noise flowing in a loop through multiple mains-connected devices (galvanic isolation has limits), but you can configure these loops such that their noise currents avoid the most-delicate analogue circuits' grounds.

The thing I'm really unsure about is capacitive coupling through power supplies, which seems to always be the troll under the bridge! Each of the two power supplies in this picture (DAC power supply and AMP power supply) has capacitive coupling to mains earth (or neutral), offering another path for common mode noise, which completes its loop with the earth (neutral) coupling of the power supply used by the digital source.

So, does star earthing actually help when it comes to RF noise? Does the separation of grounds within a DAC into digital and analogue stars referenced to a chassis star help to minimise the sound quality problems caused by RF noise? With this configuration, can the RF noise loop be kept away from flowing through the DAC's analogue circuit ground?

 

[piguetpolo]

Well

I have Double Helix Prion4 BNC custom between M Scaler and Dave, which was custom made and cost a bomb, do not want to try toslink to discover it was better, will live with what I have.

Currently I'm using dual Audience Studio One (AU24se) BNCs from HMS to TT2 which I thought sounded great.

They do, but reading these last several pages here, I decided to switch to a full run of optical from source to TT2 and power it off a 12v Lithium battery. I had to use a Lifatec glass optical as the stock Chord optical provided wasn't good enough to do the max optical 4x upscaling.

The results were immediately super smooth, grain free, more analog-like and fuller. While a great improvement, the battery power source made the sound "darker and grounded" and lose the bit of top end "air" audiophiles love. Powering the HMS using the 12V linear power supply brought some air back.

Though I can only run 4x, the grain free output sound is better than 16x so I'm gonna run it like this from here on out. Now I'm looking at OptoDX as an option to get that function back.

 

[Reactcore]

Powering the HMS using the 12V linear power supply brought some this air back.

Now try also stock PSU's with the optic chain..
ull see theyre actually good

You can also (let) build a dual optic link yourself.

 

[piguetpolo]

Now try also stock PSU's with the optic chain..
ull see theyre actually good

You can also (let) build a dual optic link yourself.

Thanks for the tip, I will try that.

I see you've built a dual optic link based on Opto DX, but using pass through power which is great for eliminating some of the spaghetti. Do you have a how-to for creating those?

 

[Reactcore]

Thanks for the tip, I will try that.

I see you've built a dual optic link based on Opto DX, but using pass through power which is great for eliminating some of the spaghetti. Do you have a how-to for creating those?

The pass through is there to keep on the same groundplane as the dac itself as one psu feeds both units that are linked via BNC.

Theres a schematic posted in the thread
But one needs some soldering skill to mount the ssopp chips i will post my PCB blueprint too if useful.

 

[Jawed]

While a great improvement, the battery power source made the sound "darker and grounded" and lose the bit of top end "air" audiophiles love. Powering the HMS using the 12V linear power supply brought some air back.

I think it's worthwhile returning to the use of the battery and living with it for a few days. "Understand" that sound, then continue with your experiments The "air" is there, it's just you've got used to an exaggerated version from before, so it takes a while to "re-balance" to the new sound.

 

[piguetpolo]

I think it's worthwhile returning to the use of the battery and living with it for a few days. "Understand" that sound, then continue with your experiments The "air" is there, it's just you've got used to an exaggerated version from before, so it takes a while to "re-balance" to the new sound.

Yes, I totally agree and have been doing 3-4 hour intervals switching between battery and LPS. Per @Reactcore recommendation and further insight, I will throw in the stock Chord SMPS as well.

The pass through is there to keep on the same groundplane as the dac itself as one psu feeds both units that are linked via BNC.

Theres a schematic posted in the thread
But one needs some soldering skill to mount the ssopp chips i will post my PCB blueprint too if useful.

I can't say that I solder very well, but I'll follow that thread and see if I can suss out what's required.

Design wise, I see you have the boxes mounted direct. Is adding a BNC cables from HMS/TT2 to the Optical boxes defeating its purpose? There's not much space between the wall and the back of the components in my setup.

 

[Reactcore]

Design wise, I see you have the boxes mounted direct. Is adding a BNC cables from HMS/TT2 to the Optical boxes defeating its purpose? There's not much space between the wall and the back of the components in my setup.

A coax not being there cant degrade anything..

You choose how to mount the connectors.. you can rotate the boxes 90 degrees if you dont mind them covering other inputs
and have the fibers on the side.

 

[pkny]

Well


Currently I'm using dual Audience Studio One (AU24se) BNCs from HMS to TT2 which I thought sounded great.

They do, but reading these last several pages here, I decided to switch to a full run of optical from source to TT2 and power it off a 12v Lithium battery. I had to use a Lifatec glass optical as the stock Chord optical provided wasn't good enough to do the max optical 4x upscaling.

The results were immediately super smooth, grain free, more analog-like and fuller. While a great improvement, the battery power source made the sound "darker and grounded" and lose the bit of top end "air" audiophiles love. Powering the HMS using the 12V linear power supply brought some air back.

Though I can only run 4x, the grain free output sound is better than 16x so I'm gonna run it like this from here on out. Now I'm looking at OptoDX as an option to get that function back.

That's what I experienced with most of the batteries (maxoak, Krisdonia...) except the unregulated direct battery output from Bixpower. It retains all the warmth, fullness, and smoothness like the others, but it adds the top end "air". For me, it is the winner.

 

[piguetpolo]

That's what I experienced with most of the batteries (maxoak, Krisdonia...) except the unregulated direct battery output from Bixpower. It retains all the warmth, fullness, and smoothness like the others, but it adds the top end "air". For me, it is the winner.

Out of curiosity, which Bixpower unregulated battery do you use?

I tend to eschew the use of batteries. Charging them can be a pain, but with the availability of rapid charging, its not as much of an issue if the option is there.

For my HMS optical + battery test, I used a Hulkman Alpha 85 car jump starters which has 12v DC output. Made sure to discharge it to 70% so the voltage is right at around 15.25v DC. At 100% charge it is putting out 16.5v. Not sure if that would fry a HMS, but I wasn't gonna take the risk.

The Hulkman has a rapid charger that can charge it from 20% to 70% in about 30 minutes. That 50% is enough for approximately 5-6 hours of continuous listening when if more than enough for me.

 

[Rob Watts]

One of the things you've never talked about is a "star" configuration for the ground in your DACs.

I've read this amazing article:

https://www.diyaudio.com/community/threads/audio-component-grounding-and-interconnection.163575/

which very clearly explains how "star earthing" should be done, and this picture from section 4 of the article:

is a very useful point of reference. It appears to show that, when using a rigorous star earthing scheme, a separate ground for the analogue circuitry is immune to digital noise circulating around the loop completed by the digital source (e.g. HMS). So, common mode noise that flows from HMS or another digital source (e.g. over USB) through the digital ground and back to the digital source stays away from the analogue ground.

In both cases the "ground busses" in this picture can be seen as "stars" so that the entire DAC has a "star of stars" configuration.

The key concept here seems to be: you can never stop noise flowing in a loop through multiple mains-connected devices (galvanic isolation has limits), but you can configure these loops such that their noise currents avoid the most-delicate analogue circuits' grounds.

The thing I'm really unsure about is capacitive coupling through power supplies, which seems to always be the troll under the bridge! Each of the two power supplies in this picture (DAC power supply and AMP power supply) has capacitive coupling to mains earth (or neutral), offering another path for common mode noise, which completes its loop with the earth (neutral) coupling of the power supply used by the digital source.

So, does star earthing actually help when it comes to RF noise? Does the separation of grounds within a DAC into digital and analogue stars referenced to a chassis star help to minimise the sound quality problems caused by RF noise? With this configuration, can the RF noise loop be kept away from flowing through the DAC's analogue circuit ground?

Star earthing is completely useless for RF noise, and will create much more RF noise. Moreover, you can not under any circumstances use star earting for SPDIF, as it must be a controlled 75 ohm return ground, which is impossible with star earthing. You will get no locking, or occasional thumps and noise as it jumps in and out of lock.

 

[pkny]

Out of curiosity, which Bixpower unregulated battery do you use?

I tend to eschew the use of batteries. Charging them can be a pain, but with the availability of rapid charging, its not as much of an issue if the option is there.

For my HMS optical + battery test, I used a Hulkman Alpha 85 car jump starters which has 12v DC output. Made sure to discharge it to 70% so the voltage is right at around 15.25v DC. At 100% charge it is putting out 16.5v. Not sure if that would fry a HMS, but I wasn't gonna take the risk.

The Hulkman has a rapid charger that can charge it from 20% to 70% in about 30 minutes. That 50% is enough for approximately 5-6 hours of continuous listening when if more than enough for me.

This is the one:

https://www.bixpower.com/product-p/bat-bp90-12v.htm

"Output II has a nominal voltage of 10.8V (Range from 9V ~ 12.6V). This port's power comes directly from battery cells without voltage regulation. When the battery is fully charged, its voltage is 12.6V. Output voltage will then decrease gradually. Most of the time, the output voltage will be around 10V ~ 11V ( nominal voltage is 10.8V). When the voltage drops to 9V, the port will shut off and stop providing power. This port can be used to power portable DVD players and digital photo frames."

Mscaler can work at 9v. The Bixpower's output range works fine with Mscaler. It can last around 10 hrs with full charge. I plug in the AC adapter when I am not listening. It will still provide power to Mscaler and get charged at the same time. Only when I start my listen session, I unplug the AC.