A novel way to massively improve the SQ of computer audio streaming

[look&listen]

40 minutes ago, afrancois said:

hope some other CA members will try to experiment with this. I feel it really helped.

Now interested in trying this, but must wait for some DIY time & extra $$. maybe after leaves raked up 

 

Thx! for sharing work & answers to many questions.

Last question  

How you cutoff 8mm strips from mu-metal sheets?

[the_doc735]

On 2/21/2017 at 9:34 PM, romaz said:

Here are some excerpts I've collected from Paul's e-mails to me over the past months. Hopefully, you'll find them useful as you make your own decisions. I've never personally met Paul (he is based in Scotland and I am in California) but based on numerous e-mail correspondences over the past year, I feel like I've gotten to know Paul pretty well and he has been a wonderful source of education for me. As you'll see from his correspondences, he is very articulate. He is also one of the nicest human beings I have met on my audio journey. I have spoken much of his SR7 on this thread and his power supplies really deserve a dedicated thread of their own but since this thread is about the things that "massively" improve either the microRendu or sMS-200 and since I consider his SR7 as the single most important component that I own that literally massively improves either of these NAAs, I feel it appropriate to to respond to your question comprehensively. Full disclosure -- I have no business relationship with Paul and I am a paying customer like anyone else.

 

Here is his response to me more than a year ago as I was comparing my HD Plex and its LT1083 regulators to Paul's own PR3 regulator design:

 

"The PR3 regulator topology used in the SR7 power supplies is my

proprietary discrete component design optimised for high quality audio

use. All the important audio related performance parameters of the PR3

regulator modules are considerably better than the LT1083

specifications.

 

The PR3 series voltage regulator noise measurements using an HP3561a

spectrum analyser specialized for low frequency measurement down to the

sub 1Hz region

 

The noise floor of 3561A is typically 15nV/sqrt Hz and the PR3 series

regulator was around 44nV/sqrt. When the 3561A noise floor is factored

into the measurement the PR3 series regulator would display lower noise

than 44nV/sqrt.

 

The ALW version of the Walt Jung ultra low noise regulator, which is the

lowest noise of the generally available DIY regulator circuits, was also

tested.

 

Here are the NF at 10Hz to 100 KHz:

PR3 series reg – 44nV/sqrt. Hz

ALW series reg – 70nV/sqrt. Hz

(40 nV/rtHz = 5 uVrms).

Measured from DC to 100 KHz the output impedance remains below 3

milliohms

 

Regulation operating bandwidth is from DC to >300 MHz allowing for device

tolerances.

 

Transient response for a 5A load current change is typically

<100nanoseconds and the settling time is also <100nanoseconds.

 

Transient current delivery for PR3HD modules >30A.

Supply line rejection >80dB DC to 100Khz (>150dB DC with double regulated PSU)

I use Panasonic FC, FM and FR low ESR high ripple current, high

temperature energy storage capacitors for excellent transient current

delivery and long working life. Alternatives can be fitted but it is

very important to ensure adequate power rating of power supply

capacitors in high current linear power supplies like the SR7. The

Panasonic capacitors are very well built and give consistently high

sound quality in capacitor tests on various audio forums."

Many have privately approached me with questions about how best to improve SQ and then stop me once I start talking about power supplies. Their response typically goes like this: "You don't have to convince me of the importance of good power, I already know this because I own an HDPlex." These folks have no idea. No offense to HDPlex but the model I own is nowhere in the same vicinity as the performance of my SR7. I also have a Teradak, Kenneth Lau, Paul Pang, iFi, and various DIY battery supplies that are now collecting dust. The only thing that comes close (that I own) is the LPS-1.

 

As I started to talk to Paul about the importance of the output impedance of a PSU, here was his informative response:

 

"Power supply output impedance is an important parameter, as are transient response, settling time, operating bandwidth and noise. For exceptional power supply design it is important to consider all of these parameters and optimise them to the best of your ability. This is what I do. The ideal power supply would have zero impedance at all frequencies of operation as you cannot develop any voltage into zero impedance no matter how much current passes through it. In the real world all circuits have some level of impedance and any current passing through this impedance will generate a voltage fluctuation, which in reality becomes an additional noise source in the system, which degrades signal integrity. It is therefore important to minimise the impedance to reduce this disturbance to the lowest level. This impedance reduction is usually achieved by an error amplifier using high levels of negative feedback, which introduces all manner of problems with operating bandwidth, transient response and settling time. This is a big subject to consider so I will not go into detail here. Suffice to say I do not use typical circuit topologies in my voltage regulator designs to achieve low impedance over a very wide operating bandwidth."

 

As you've seen above, Paul lists his measurements for these parameters. No one else seems to do this either because they don't have the measuring equipment to do so or they don't believe these parameters are even important. Without measurements, it's hard to even know how to shop for a good PSU and so the end user is forced to do his/her own listening comparisons or else make a purchase based on speculative comments.

Here is his response regarding the importance of using high quality, expensive discrete components. Paul's supplies are not inexpensive but it's not because it's all going into his pocket. Most importantly, IMO, the performance for the dollar is there:

 

"Some industry participants have been minimising the importance of “expensive” discrete component high performance voltage regulators in their marketing and concentrating their marketing stance on other parameters. I have to disagree here as I have conducted extensive testing in these areas over many years. Everything you use to build a power supply will have a sonic signature that will imprint on the achievable sound quality. Using low cost industrial voltage regulators with limited performance will just bottleneck the overall performance that is achievable and no amount of attention to detail in the other areas will override this."

Paul makes 3 lines of PSUs, from the SR3 to the SR7 and here is how he describes them:

 

"The SR3 was originally custom designed for a customer to improve on the performance offered by the Optima Red Top car battery used for the Altman Attraction DAC. As I foresaw additional sales for the SR3 for a wider variety of equipment I wanted it to be small enough and light enough to ship world wide via the Royal Mail small packet rate (under 2Kg) and of reasonable price. The mains transformer was the best of the “off the shelf” transformers available in the UK and the “off the shelf” chassis limited the transformer size to 60VA. The current PHD SR3 is rated at 30W continuous delivery and 240W transient delivery.

 

The SR5 was designed in response to requests for Mac Mini rated power supplies. The power rating had to be 80W continuous and it can also provide 350W transient delivery. This is achieved by increasing the mains transformer rating to 160VA, additional energy storage capacitance for robust power delivery with large dynamic load transients and the design of a custom chassis to house this and the electronics and heat sink required for this power upgrade. I also increased the power ratings of the Schottky Barrier rectification and the output stage device to provide the power rating with comfortable margins for safety and long life. More space within the chassis allowed me to design a mains transformer that would address the shortcomings of “off the shelf” mains transformers. In particular, core saturation is a big issue as the transformer operation stalls when this happens. Other big issues are electrical and mechanical noise. The SR5 and SR7 mains transformers are carefully wound on manually operated winding machines using over sized grain orientated silicon steel cores and high quality wire to minimise these issues. They are designed for low impedance operation and can deliver very large transient currents to the load.

 

The SR7 is essentially a higher power version of the SR5 with increased ratings for all power devices and a larger 250VA mains transformer giving a 125W continuous power rating and a 480W transient power rating for the more power hungry applications.

 

Many customers asked for a “Multirail” power supply to reduce space requirement for multiple power supplies in systems and also to reduce overall cost so I then designed the SR7 Multirail with up to four galvanically isolated supply rails to avoid interaction between the various items of equipment to be powered. The SR5 can also be configured as a Multirail but space limits the number of rails to two.

 

The best way to describe the performance between the three power supply levels is to use the car engine analogy. A small runabout with a 1.2 litre engine, a hot hatchback with a 1.6 litre fuel injected engine, a larger family saloon with a 3 litre fuel injected engine and a sports car with full engine management. Braking systems for these cars will be suitably rated to cope with the engine power. All four cars will get you from A to B but the ride will be progressively more responsive, dynamic and stable as you go up the range of cars. The runabout is the equivalent of a low cost power supply upgrade, the SR3 is the hot hatchback with acceptable all round performance and a lively drive, the SR5 is the 3 litre family saloon with a more stable but responsive drive and the SR7 is the sports car with even better performance.

 

As you go up the range in power supplies this translates into the traits you were hearing at the listening trials. The musical performance in all areas just improves with a more stable three dimensional presentation that is more robust when the going gets busy with the better power supplies."

More recently, he stated it to me this way:

 

"The SR range of high performance power supplies were designed for powering both analogue and digital audio and video equipment. The same proprietary ultra low noise high performance discrete component voltage regulator circuit topology is used in the SR3, SR5 and SR7 power supplies. The SR3 uses a standard 50VA mains transformer, the SR5 uses a custom manufactured 160VA mains transformer and the SR7 uses a custom manufactured 250VA mains transformer. The SR7MR uses a custom manufactured mains transformer with up to 500VA rating depending on the overall rail requirements. The custom manufactured mains transformers use oversized grain orientated silicon steel cores and are wound to avoid core saturation in use and to operate quietly both electrically and mechanically. Schottky Barrier rectifiers are used throughout the range, as they do not generate reverse recovery transients and their associated harmonic distortions.

 

The error amplifier used in the voltage regulator modules has the following specification :-

 

Noise voltage < 0.5 nanovolts root Hz

Operating Bandwidth > 300 Mhz

Supply line rejection > 80 dB DC to 100 KHz

Output impedance < 3 milliohms DC to 100 KHz

Transient response and settling time < 100 nanoseconds

 

As the SR3, SR5 and SR7 all use the same high performance regulator circuit topology they all have a similar sonic signature musically. Moving up the range allows better quality lower impedance mains transformers and up-rated rectification and regulator output stage providing a reduction in power supply output impedance, which in turn reduces interaction with the load. The increased energy storage capacitor bank also reduces rectifier ripple noise and RFI break through from the mains supply. Another benefit of the increased energy storage capacitance is with transient response and settling time. The net effect musically is to provide progressively larger, more stable and more robust soundstage particularly where large dynamic load current swings occur, as well as, a lower noise floor and improved timbre and temporal accuracy.

 

These power supplies are available with fixed voltage output from 1.6v to 30v or variable voltage output with a 10 volt span on voltage setting, within this range, using the precision adjustment potentiometer internally situated on the regulator module.

 

Continuous power output ratings – For fixed output voltage versions the SR3 provides 25W, the SR5 provides 80W and the SR7 provides 125W and the SR7MR chassis can support up to 250W spread across the rails. The SR5 can support one 6A module and the SR7 can support one 10A module. The output voltage and output current can be specified within this power rating using the formulae :-

 

V = W/I

I = W/V

 

Where V is output voltage, W is the available power in Watts and I is the output current in Amps.

 

If you require help with power supply specification I will be pleased to help you.

 

For variable output voltage versions of the power supplies, set at the maximum output voltage of the range, the SR3 provides 25W, the SR5 provides 80W and the SR7 provides 125W. Lower voltage settings than maximum will increase the voltage across the regulator output device, which will increase the heat generated in this device. To maintain safe operating temperatures and long term reliability the current rating should be de-rated by 8% per volt when reducing the output voltage level on variable output voltage versions.

 

The SR5 and SR7 power supplies are available in Multirail versions SR5MR and SR7MR with galvanic isolation between the supply rails to avoid ground return current intermodulation (ground loops) where more than one item of equipment is powered from the same power supply. The SR5MR can support one 6A regulator module and one 3A regulator module or two 3A modules. The SR7MR can support one 10A module and up to three additional 3A modules or two 6A modules and up to two additional 3A modules.

 

XL ultra low impedance (< 1 milliohm) connectors and fine silver internal wiring between capacitor banks, regulator modules and the output connectors, can be fitted to the SR5 and SR7 power supplies.

 

The SR3, SR5 and SR7 single rail supplies are also available in DR versions where two of the high performance voltage regulators are cascaded to a give supply line and rectification interference rejection exceeding 150 dB from DC to 100 KHz. This provides lower overall noise levels than the standard power supplies.

 

Current Prices 200117

 

SR3 £300

SR3DR £500

 

SR5 £600

SR5XL £678

SR5DR £800

SR5DRXL £885

SR5MR2 £800

SR5MR2XL £970

 

SR7 £750

SR7XL £870

SR7DR £950

SR7DRXL £1080

SR7MR2 £950

SR7MR2XL £1190

SR7MR3 £1150

Here is his pricing for his DC leads:

 

Current Prices 200107

 

All prices are for1 metre lengths with a Switchcraft DC plug. Alternative lengths and connectors can be quoted for if required. Cable impedance reduces with higher current rating. XL ultra low impedance (< 1 milliohm) connectors can be fitted to the SR5 and SR7 DC Leads.

 

3A current rating :-

DC3C annealed copper with Teflon insulation £050

DC3FS annealed fine silver with Teflon insulation £085

 

6A current rating :-

DC6C annealed copper with Teflon insulation £075

DC6FS annealed fine silver with Teflon insulation £145

DC6FSXL annealed fine silver with Teflon insulation £186

 

10A current rating :-

DC10C annealed copper with Teflon insulation £100

DC10FS annealed fine silver with Teflon insulation £229

DC10FSXL annealed fine silver with Teflon insulation £270

There is also the option for Paul to make you a double regulated PSU (with cascading regulators) and this can be discussed with Paul for those who want his very best. I cannot yet tell you what this sounds like because I haven't received mine yet. Considering the performance I am getting from his SR7, it is my opinion that this is some of the best money I have ever spent on audio. Without question, quality is the foundation of anything that is good in audio. Paul does not have a presence here on CA and for those who wish to correspond with him, you can do so via e-mail at [email protected].

does paul hynes only do "SR1" now? and no custom builds at all?

[afrancois]

35 minutes ago, look&listen said:

Now interested in trying this, but must wait for some DIY time & extra $$. maybe after leaves raked up 

 

Thx! for sharing work & answers to many questions.

Last question  

How you cutoff 8mm strips from mu-metal sheets?

By hand with a pair of metal sissors. See picture.

[RickyV]

7 minutes ago, afrancois said:

By hand with a pair of metal sissors. See picture.

What about the mu metal braiding @lmitche  found? Much simpler and flexible.

 

http://custommagneticshielding.magneticshield.com/viewitems/magnetic-shielding-for-wiring-applications/co-netic-aacableshield

 

rick

[lmitche]

4 hours ago, shadowlight said:

@lmitche, is the Intel NUC that you are are talking about NUC7CJYH1, based on Celeron based?  If yes, Fry's has that on sale for 109 in case anyone is looking for it.

 

https://www.frys.com/product/9540382?site=sr:SEARCH:MAIN_RSLT_PG

 

the pentium based one is listed at 149 -  https://www.frys.com/product/9540392?site=sr:SEARCH:MAIN_RSLT_PG

Yes, that's the one! Nice price. Booting from the HDD means no need for the emmc and throw away Windows license.

[lmitche]

With a quiet day, I was able to test some configuration changes.

 

- Audiolinux extreme command line mode

 

I believe this is a low latency kernel and it comes with warnings about extreme heat. It does indeed yield another level of clarity, and temps raised about 2C to a peak of 46C. This is keeper.

 

- Boot from HDD vs EMMC, should be no difference

 

After turning off the emcc device off in the bios, (which is a good place to hide a backup copy of the boot and root partitions), booting from the HDD does seem to bring a small increase in SQ. I am on the fence about this one, but like the backup strategy.

 

- Use of usb nic vs. Internal nic

 

I went back in forth on this one a couple times. In the end the USB 3 nic is a keeper. Bass is tighter and mids take on another very welcome increase in presence. It's like the vocalists just got 10 years younger and stepped 5 feet closer to the mike. Another keeper.

[Lobbster]

On 9/12/2018 at 11:55 AM, Lobbster said:

What's the best insulation material between shields for JSSG360 mods?

I think I found my answer 3M Temflex

Looks like the stuff I remember under the hood of our 50/60's cars before the days of vinyl electricians tape - cotton and rubber friction tape.

Grainger stocks it.

 

 

[lmitche]

16 hours ago, Lobbster said:

I think I found my answer 3M Temflex

Looks like the stuff I remember under the hood of our 50/60's cars before the days of vinyl electricians tape - cotton and rubber friction tape.

Grainger stocks it.

 

 

Hmmm, I remember the smell of that stuff. If it's what I think it is, the adhesive is tough to wash off your hands.

[look&listen]

9 minutes ago, lmitche said:

If it's what I think it is, the adhesive is tough to wash off your hands.

IIRC, dries out with age, heat, become horrible to clean off.

[str-1]

Just posted this on the ‘USB Cables Comparison’ thread but thought I should also post here.

 

I’m find it a little frustrating comparing three upmarket USB cables in my setup (see signature).  

 

Recent changes I have made to the system have cleaned things up considerably and I am now finding it harder to reliably tell the difference between these cables and with a heavily ferrite’d stock cable.  It feels like I have now removed further upstream some of the crud that these cables normally have variable success in dealing with.

 

The cable I expected to perform the best based on reputation (Sablon) also happens to be the longest at 1.2m, although the signal and power lines run in separate shielded cables between the connectors.  The stock cable is 1m and the upmarket cable I expected to sound second best is 0.7m (Lush).  I have a third upmarket cable (Curious) which is a little harder to include in the comparison because it is only 0.20m long.  Does the different lengths of these cables mean this isn’t a level playing field for comparison?  I have heard it said many times that USB cables should be as short as possible but I have no feel for how big an impact USB cable length would/could have on sound quality.  

 

Generally, what differences should I expect to hear with different lengths of the same cable?  In a really good clean transparent system should I expect to hear any difference between a 0.5m and a 1.2m cable?  Thanks for any thoughts.

[Johnseye]

39 minutes ago, str-1 said:

Just posted this on the ‘USB Cables Comparison’ thread but thought I should also post here.

 

 

Link please?

[str-1]

34 minutes ago, Johnseye said:

 

Link please?

https://www.computeraudiophile.com/forums/topic/14124-usb-cable-comparisons/?do=findComment&comment=876207

 

[Lobbster]

4 hours ago, lmitche said:

Hmmm, I remember the smell of that stuff. If it's what I think it is, the adhesive is tough to wash off your hands.

 

L'Odeur eh? Fabrique en Canada - Ruban de Hockey?  Sacre Bleu - pas possible!

 

Every self respecting Canadian can tape their stick with out messing their hands - MERCI!

 

I don't smell anything, but as long as it doesnt smell like the INSIDE of a hockey bag, I probably won't notice?

[Lobbster]

4 hours ago, look&listen said:

IIRC, dries out with age, heat, become horrible to clean off.

Rubber is a natural compound that won't dry out AFAIK.

It's a very good insulator, resistant to moisture, chemicals and is flexible/elastic. I bought a roll of 3M Super 33+ as well. It's PVC and has super strong adhesive, but I still think the rubber/cotton tape will give me a more flexible cable. It's not really exposed to any extreme environmental conditions.

 

Seemed  the choice of natural products between the shields made some sense. Can't hurt to try I guess.

[austinpop]

Network tuning update

 

A few weeks ago, I wrote my impressions of the SOtM switch. In that review, I again referred to a recurring theme in my setup, where I said:

 

Quote

The network scenarios just had a slightly harsher edge to them.

 

and

 

Quote

This direct path always sounded just that extra bit more relaxed, natural, and fatigue-free.

 

Well, I've been scratching my head at this to understand the source of this harshness. Was this an inherent characteristic of the Zenith SE's ethernet interface, or could there be more going on? After auditing my entire network chain, I realized the answer was under my very nose. And it's a bit embarrassing. To understand, here's a picture of my network topology:

 

 

And for completeness, here's the audio topology:

 

You'll notice that everything up the chain to the cable modem is on an LPS, but what the picture does not show is the AC power source. This is the embarrassing bit. For historical reasons I won't go into, my network closet (top picture) is powered by an APC 350VA UPS. In this latest audit of my system, it finally registered on me (duh!) that this UPS must be generating very noisy AC to the HDPlex LPS. Following @JohnSwenson's advice in the isolation transformer thread, I got myself an unfiltered Tripplite power strip (this one can be folded into convenient shapes).

 

Wow - much improved! I can't believe the crud the UPS was putting into the network gear made it across the entire topology. I've only done an evening's worth of listening, but at this point, the gap between network playback and local playback on the SE has shrunk. Not completely disappeared, but definitely smaller.

 

Encouraged by this, I have a plan to continue cleanup of my network. Referring back to my network topology, here's the plan:

1. I still have SMPSes in my network closet for things like the NAS, assorted adapters (like my Directv broadband adapter, a broadband alarm adapter, etc). I plan to replace all these SMPSes with an HDPlex 200W LPS. This still does not eliminate SMPSes for the ASUS WAP and a couple more switches. These are in other parts of the house but wire back to the network closet. I will address these with isolation. See next 2 points.
2. I plan to replace my DGS2205 switch with a JS approved Netgear GS108, powered by an existing HDPlex rail, and shunted with a JSGT.
3. The Archer router will only have a direct connection from my listening room on one port, and the Netgear GS108 switch on another.
4. All other equipment: NAS, adapters, other switches, the ASUS, will all connect to the GS108. Hopefully, this will block the bulk of both low-impedance SMPS noise (via the port magnetics) and the high-impedance noise, via the JSGT, from my audio topology. Don't forget, my TLS switch is also ground shunted, but I don't know if the underlying Dlink switch, on which it is modded, has isolating port magnetics.

Once I've done all that, I'll do another round of listening tests, and report back.

[ElviaCaprice]

43 minutes ago, austinpop said:

 

You'll notice that everything up the chain to the cable modem is on an LPS, but what the picture does not show is the AC power source. This is the embarrassing bit. For historical reasons I won't go into, my network closet (top picture) is powered by an APC 350VA UPS. In this latest audit of my system, it finally registered on me (duh!) that this UPS must be generating very noisy AC to the HDPlex LPS. Following @JohnSwenson's advice in the isolation transformer thread, I got myself an unfiltered Tripplite power strip (this one can be folded into convenient shapes).

 

Wow - much improved! I can't believe the crud the UPS was putting into the network gear made it across the entire topology. I've only done an evening's worth of listening, but at this point, the gap between network playback and local playback on the SE has shrunk. Not completely disappeared, but definitely smaller.

 

 

 

That Tripplite still has a breaker installed.  Better is this 20A Tripplite that requires hard wiring.  It's what I use.   In fact I wired it directly from my 1KVA Topez direct using 10AWG 3 conductor wire. 

[lmitche]

5 hours ago, austinpop said:

Network tuning update

 

A few weeks ago, I wrote my impressions of the SOtM switch. In that review, I again referred to a recurring theme in my setup, where I said:

 

 

and

 

 

Well, I've been scratching my head at this to understand the source of this harshness. Was this an inherent characteristic of the Zenith SE's ethernet interface, or could there be more going on? After auditing my entire network chain, I realized the answer was under my very nose. And it's a bit embarrassing. To understand, here's a picture of my network topology:

 

 

And for completeness, here's the audio topology:

 

You'll notice that everything up the chain to the cable modem is on an LPS, but what the picture does not show is the AC power source. This is the embarrassing bit. For historical reasons I won't go into, my network closet (top picture) is powered by an APC 350VA UPS. In this latest audit of my system, it finally registered on me (duh!) that this UPS must be generating very noisy AC to the HDPlex LPS. Following @JohnSwenson's advice in the isolation transformer thread, I got myself an unfiltered Tripplite power strip (this one can be folded into convenient shapes).

 

Wow - much improved! I can't believe the crud the UPS was putting into the network gear made it across the entire topology. I've only done an evening's worth of listening, but at this point, the gap between network playback and local playback on the SE has shrunk. Not completely disappeared, but definitely smaller.

 

Encouraged by this, I have a plan to continue cleanup of my network. Referring back to my network topology, here's the plan:

1. I still have SMPSes in my network closet for things like the NAS, assorted adapters (like my Directv broadband adapter, a broadband alarm adapter, etc). I plan to replace all these SMPSes with an HDPlex 200W LPS. This still does not eliminate SMPSes for the ASUS WAP and a couple more switches. These are in other parts of the house but wire back to the network closet. I will address these with isolation. See next 2 points.
2. I plan to replace my DGS2205 switch with a JS approved Netgear GS108, powered by an existing HDPlex rail, and shunted with a JSGT.
3. The Archer router will only have a direct connection from my listening room on one port, and the Netgear GS108 switch on another.
4. All other equipment: NAS, adapters, other switches, the ASUS, will all connect to the GS108. Hopefully, this will block the bulk of both low-impedance SMPS noise (via the port magnetics) and the high-impedance noise, via the JSGT, from my audio topology. Don't forget, my TLS switch is also ground shunted, but I don't know if the underlying Dlink switch, on which it is modded, has isolating port magnetics.

Once I've done all that, I'll do another round of listening tests, and report back.

If you have a spare USB 3 port on your server try one of these:

 

https://www.bestbuy.com/site/insignia-usb-3-0-to-gigabit-ethernet-adapter-white/3510527.p?skuId=3510527&amp;cmp=RMX&amp;extStoreId=1067&amp;ref=212&amp;loc=1&amp;gclid=EAIaIQobChMIqcWhyqS_3QIVxEsNCh1L8QGbEAQYASABEgKZRfD_BwE&amp;gclsrc=aw.ds

 

I used this on my upsampling server for over a year and just for grins tried it on the NUC the other day. It's a keeper.

 

From there I have a 7 foot cable run to one of these:

 

https://www.netgear.com/home/products/networking/wifi-range-extenders/ex7000.aspx

 

powered by a 13.5 volt sigma 11 dropped to 12 volts with a lt3045 and a shunt to ground. The AC comes from the same isolation transformer as the other components. I've tried adding Netgear, Dlink and Cisco switches, all powered by lt3045s and this sounds best. A second router creates a music subnet ahead of the ex7000.

[afrancois]

6 hours ago, austinpop said:

Network tuning update

 

A few weeks ago, I wrote my impressions of the SOtM switch. In that review, I again referred to a recurring theme in my setup, where I said:

 

 

and

 

 

Well, I've been scratching my head at this to understand the source of this harshness. Was this an inherent characteristic of the Zenith SE's ethernet interface, or could there be more going on? After auditing my entire network chain, I realized the answer was under my very nose. And it's a bit embarrassing. To understand, here's a picture of my network topology:

 

 

And for completeness, here's the audio topology:

 

You'll notice that everything up the chain to the cable modem is on an LPS, but what the picture does not show is the AC power source. This is the embarrassing bit. For historical reasons I won't go into, my network closet (top picture) is powered by an APC 350VA UPS. In this latest audit of my system, it finally registered on me (duh!) that this UPS must be generating very noisy AC to the HDPlex LPS. Following @JohnSwenson's advice in the isolation transformer thread, I got myself an unfiltered Tripplite power strip (this one can be folded into convenient shapes).

 

Wow - much improved! I can't believe the crud the UPS was putting into the network gear made it across the entire topology. I've only done an evening's worth of listening, but at this point, the gap between network playback and local playback on the SE has shrunk. Not completely disappeared, but definitely smaller.

 

Encouraged by this, I have a plan to continue cleanup of my network. Referring back to my network topology, here's the plan:

1. I still have SMPSes in my network closet for things like the NAS, assorted adapters (like my Directv broadband adapter, a broadband alarm adapter, etc). I plan to replace all these SMPSes with an HDPlex 200W LPS. This still does not eliminate SMPSes for the ASUS WAP and a couple more switches. These are in other parts of the house but wire back to the network closet. I will address these with isolation. See next 2 points.
2. I plan to replace my DGS2205 switch with a JS approved Netgear GS108, powered by an existing HDPlex rail, and shunted with a JSGT.
3. The Archer router will only have a direct connection from my listening room on one port, and the Netgear GS108 switch on another.
4. All other equipment: NAS, adapters, other switches, the ASUS, will all connect to the GS108. Hopefully, this will block the bulk of both low-impedance SMPS noise (via the port magnetics) and the high-impedance noise, via the JSGT, from my audio topology. Don't forget, my TLS switch is also ground shunted, but I don't know if the underlying Dlink switch, on which it is modded, has isolating port magnetics.

Once I've done all that, I'll do another round of listening tests, and report back.

Good you came to the same conclusion regarding SMPS'es I wrote about many posts ago.

 

[the_doc735]

6 hours ago, austinpop said:

Network tuning update

 

A few weeks ago, I wrote my impressions of the SOtM switch. In that review, I again referred to a recurring theme in my setup, where I said:

 

 

and

 

 

Well, I've been scratching my head at this to understand the source of this harshness. Was this an inherent characteristic of the Zenith SE's ethernet interface, or could there be more going on? After auditing my entire network chain, I realized the answer was under my very nose. And it's a bit embarrassing. To understand, here's a picture of my network topology:

 

 

And for completeness, here's the audio topology:

 

You'll notice that everything up the chain to the cable modem is on an LPS, but what the picture does not show is the AC power source. This is the embarrassing bit. For historical reasons I won't go into, my network closet (top picture) is powered by an APC 350VA UPS. In this latest audit of my system, it finally registered on me (duh!) that this UPS must be generating very noisy AC to the HDPlex LPS. Following @JohnSwenson's advice in the isolation transformer thread, I got myself an unfiltered Tripplite power strip (this one can be folded into convenient shapes).

 

Wow - much improved! I can't believe the crud the UPS was putting into the network gear made it across the entire topology. I've only done an evening's worth of listening, but at this point, the gap between network playback and local playback on the SE has shrunk. Not completely disappeared, but definitely smaller.

 

Encouraged by this, I have a plan to continue cleanup of my network. Referring back to my network topology, here's the plan:

1. I still have SMPSes in my network closet for things like the NAS, assorted adapters (like my Directv broadband adapter, a broadband alarm adapter, etc). I plan to replace all these SMPSes with an HDPlex 200W LPS. This still does not eliminate SMPSes for the ASUS WAP and a couple more switches. These are in other parts of the house but wire back to the network closet. I will address these with isolation. See next 2 points.
2. I plan to replace my DGS2205 switch with a JS approved Netgear GS108, powered by an existing HDPlex rail, and shunted with a JSGT.
3. The Archer router will only have a direct connection from my listening room on one port, and the Netgear GS108 switch on another.
4. All other equipment: NAS, adapters, other switches, the ASUS, will all connect to the GS108. Hopefully, this will block the bulk of both low-impedance SMPS noise (via the port magnetics) and the high-impedance noise, via the JSGT, from my audio topology. Don't forget, my TLS switch is also ground shunted, but I don't know if the underlying Dlink switch, on which it is modded, has isolating port magnetics.

Once I've done all that, I'll do another round of listening tests, and report back.

quote:

"Many have privately approached me (paul hynes) with questions about how best to improve SQ and then stop me once I start talking about power supplies. Their response typically goes like this: "You don't have to convince me of the importance of good power, I already know this because I own an HDPlex." These folks have no idea. No offense to HDPlex but the model I own is nowhere in the same vicinity as the performance of my SR7. I also have a Teradak, Kenneth Lau, Paul Pang, iFi, and various DIY battery supplies that are now collecting dust."

https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-computer-audio-streaming/?page=30

[asdf1000]

An interesting post by Rob Watts here about linear PSU's vs SMPS. I don't know if we have any PSU experts here, other than @JohnSwenson

 

Obviously Rob couldn't have possibly inspected/measured every linear PSU on the planet but I assume he has good experience with a variety.

 

"And before anybody starts saying LPS, these devices provide no rejection from 10 MHz and above, as they do not employ RF filters- but a SMPS must employ filters, both on the OP and back to the mains.

As you know, RF noise creates noise floor modulation, as the intermodulation distortion from random RF noise is a white noise modulated by the wanted signal. This then results in noise floor modulation, and is very very audible. It accounts for the things sounding brighter and less smooth; additionally, when you reduce RF noise, things sound considerably warmer and darker, and one consequence of this is perception of tempo - more midrange gives the impression of a slower tempo, as individual instruments have much more body.

Now if somebody prefers the brighter sound from more noise floor modulation, then fine - that's their taste and preference. But it's not accurate."

 

https://www.head-fi.org/threads/chord-electronics-hugo-2-the-official-thread.831345/page-934#post-14445774

 

 

 

 

[paulhynes]

48 minutes ago, Em2016 said:

An interesting post by Rob Watts here about linear PSU's vs SMPS. I don't know if we have any PSU experts here, other than @JohnSwenson

 

Obviously Rob couldn't have possibly inspected/measured every linear PSU on the planet but I assume he has good experience with a variety.

 

"And before anybody starts saying LPS, these devices provide no rejection from 10 MHz and above, as they do not employ RF filters- but a SMPS must employ filters, both on the OP and back to the mains.

As you know, RF noise creates noise floor modulation, as the intermodulation distortion from random RF noise is a white noise modulated by the wanted signal. This then results in noise floor modulation, and is very very audible. It accounts for the things sounding brighter and less smooth; additionally, when you reduce RF noise, things sound considerably warmer and darker, and one consequence of this is perception of tempo - more midrange gives the impression of a slower tempo, as individual instruments have much more body.

Now if somebody prefers the brighter sound from more noise floor modulation, then fine - that's their taste and preference. But it's not accurate."

 

https://www.head-fi.org/threads/chord-electronics-hugo-2-the-official-thread.831345/page-934#post-14445774

 

 

 

 

 

Actually that statement regarding LPS by Rob Watts is not entirely true but it could be applied to most of the integrated circuit voltage regulator solutions currently available.

 

Nowadays there are a few integrated circuit voltage regulators with exceptional supply line rejection, however their load current transient response is usually quite slow and the settling time after a load current transient is also usually slow and less than ideal for audio power supply use. Such voltage regulators react to fast load current changes by adding signal related noise spikes and low level ringing to the noise floor. This noise floor modulation is one of the causes of brighter sound (noise spikes) and false ambient reverberation (low level ringing) and can be high enough in level to mask the natural transient response and ambience of the musical event.

 

As Rob says, some people like the resulting bright airy sound of noise floor modulation. It is not something I can live with and I much prefer to hear the music unadulterated.

 

 

[seeteeyou]

43 minutes ago, Em2016 said:

Now if somebody prefers the brighter sound from more noise floor modulation, then fine - that's their taste and preference. But it's not accurate.

 

https://www.head-fi.org/threads/chord-electronics-hugo-2-the-official-thread.831345/page-934#post-14445774

 

Sometimes he's saying stuff that totally cracked me up and here's an analogy

 

https://kellybroganmd.com/depression-serotonin/

Quote

To understand what imbalance is, we must know what balance looks like, and neuroscience, to date, has not characterized the optimal brain state, nor how to even assess for it.

 

https://www.nytimes.com/2012/04/22/magazine/the-science-and-history-of-treating-depression.html

Quote

In The New York Review of Books, Marcia Angell, a former editor of The New England Journal of Medicine, wrote: “After decades of trying to prove [the chemical-imbalance theory], researchers have still come up empty-handed.” Jonathan Rottenberg, writing in Psychology Today, skewered the idea thus: “As a scientific venture, the theory that low serotonin causes depression appears to be on the verge of collapse. This is as it should be; the nature of science is ultimately to be self-correcting. Ideas must yield before evidence.”

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172306/

Quote

Tianeptine is an SSRE, a selective serotonin reuptake enhancer. Instead of increasing the amount of serotonin in the brain, it is supposed to decrease it. If the theory that depression is caused by a deficiency of serotonin were correct, we would expect to make depression worse.

 

https://youtu.be/ISptt3CRAqc

 

 

What really *IS* "accurate" and how does one actually define that? Is it "accurate" to his ears and brain? Maybe his taste and preference are the only yardsticks when it comes to accuracy? LOL

[asdf1000]

11 minutes ago, seeteeyou said:

What really *IS* "accurate" and how does one actually define that? Is it "accurate" to his ears and brain? Maybe his taste and preference are the only yardsticks when it comes to accuracy? LOL

 

Lol good questions. I guess it may possible that he relies on the (state of the art?) measured performance of his gear, as a starting point? I don't know though.

 

https://www.stereophile.com/content/chord-electronics-dave-da-processor-measurements

 

[hieukm]

Love Chord Dac + Blu2 as i have them but Rob Watts say his el cheapo Chinese SMPS is better than all the LPS out there is laughable. 

[asdf1000]

14 minutes ago, hieukm said:

Love Chord Dac + Blu2 as i have them but Rob Watts say his el cheapo Chinese SMPS is better than all the LPS out there is laughable. 

 

Well this is the point I made earlier - it's not possible he's inspected/measured every linear PSU on the planet. But I assume he's commenting based on a variety of linear PSU's that he has inspected or measured.

 

As he also says, some people actually prefer a slightly brighter sound with different PSU's, thinking they are hearing more 'detail' - when in reality it's more RF getting through causing higher IM distortion, resulting in the brighter sound, mistaken for more 'detail'.

 

This is the tricky thing when our own preferences vary so much. But he does have access to measurement gear that we don't...