Mains conditioner for SMPSs?

[sandyk]

8 hours ago, mansr said:

Unplug the SMPS strip and see if you can hear any difference in noise from the speakers with the volume turned up to 11. If not, a power conditioner will be of no benefit.

 

HF mains related artifacts can, and often do, degrade the performance of DACs etc. without necessarily being noticed in other components such as well designed power amplifiers.

 Many reviewers disconnect all non essential SMPS plugpacks etc before commencing equipment reviews.

[sandyk]

6 hours ago, marce said:

How do you check if high frequency noise doesn't alter the sound how do you check for it?

To check for noise needs measurements, a scope at least really. Then you have to determine whether the noise is having an effect on the final analogue output and at what level, again as some noise is way down, you can't perceive it, so again without measurements you have no reference.

This is obviously much easier to do in the Analogue area.

 With my Class A Preamp for example, I used my C.R.O at maximum sensitivity preceded by a very Low Noise battery operated preamplifier with a gain of 10

[sandyk]

2 hours ago, Speedskater said:

Digital noise won't affect the analog output s/n ratio. What it will affect is the data integrity. So lost data bits can cause the error correction system to work overtime.

 

It has nothing to do with lost Data Bits. It's a masking of low level detail such as low level harmonics, like there is a veil present.

It can even give the appearance of added HF detail in some cases.

 To quote Barry Diament  "as though some random treble energy surrounded the details in the recordings."

[sandyk]

6 hours ago, Speedskater said:

What kind of noise and where in the circuit is this noise?

I am far from the only member that will tell you this about " digital veils"

 You and the other sceptics like Mansr and Marce  have qualifications in this area. Perhaps you should put some of your undoubted expertise in these areas to good use and investigate what numerous people report hearing with less than well optimised digital audio ?

If you don't wish to believe what myself, Blacmorec and many others are saying, then ask the vast majority of the participants in Rajiv's thread in Music Servers.

[sandyk]

3 minutes ago, Speedskater said:

OK, so tell me about it. What is veiling what?

 

You guys refuse to accept anything that this old fart reports, so I suggest that you ask the same question in that other massive thread. BTW, the quote that I mentioned was from Barry after comparing a couple of comparison CD-Rs that I sent him AFTER he ripped them to his HDD for seamless switching between versions using his Studio gear. It was about the version ripped using a cheap external USB powered DVD writer where his wife also reported hearing the same under NON sighted conditions.

[sandyk]

20 minutes ago, fas42 said:

Part of the skill set is to be able to listen to equipment as part of a working system, and have no trouble hearing it misbehaving - call it a form of Quality Assurance if you like, 😉. Unfortunately, there is now a ritualistic downplaying of the human ability to perceive 'wrongness' in what they listen to - because, well, it makes life easier for the geeks ... "Show us the measurements !!!"

 

 +1

[sandyk]

7 hours ago, semente said:

@The Computer Audiophile could you please move this question to the General Forum?

 

It's scope of te discussion has widened immensely and I think that the answer is no longer a simple matter of Yes or No...

 Semente

 No matter where the thread is, you are still going to get the exact same entrenched views from both sides of the great forum divide.

 The obvious answer here is to try what you suggested in #76 and decide for yourself.

 

Regards

Alex

[sandyk]

2 hours ago, semente said:

 

I was thinking about USB.

 

 

Again, I was thinking about a computer feeding a DAC using USB.

 

 

Can you somehow determine how clean and crisp the analogue DC voltage levels are and if they are affected by noise?

 

 

What would you measure and what would you expect to find if noise were to affect the D/A conversion?

I don't think that it would be possible to compare the input with the output, would it? Could you meaningfully compare conversion (analogue output) of a clean vs a dirty signal, not static test tones but live streaming music or at least something more complex and varied?

 

 

 

 

 

 

 

 

 

If you want further information from someone with plenty of hands on experience in this area , perhaps you should direct these questions to John Swenson in the Uptone Audio area of the forum so that your thread doesn't become rather unpleasant and one sided due to the scepticism  of  several members that this is even an issue, and that  reports to the contrary are only hearsay. . 

[sandyk]

38 minutes ago, semente said:

My bad.

Can those voltage changes be affected by noise in a way that affects D/A conversion, that was my question?

 Check USB Signals- Wikipedia for an example of a "perfect" USB waveform. 

https://en.wikipedia.org/wiki/USB_(Communications)

 

Click on the image several times for a larger image.

[sandyk]

5 hours ago, Summit said:

The negative effect of noise is well known and is not made up by subjective audiophiles. Intel for example have measured the interference of wireless devices operating in the 2.4 GHz ISM band and its effect on hard drives, USB muse and cables. Intel have tested and measured with and without shielding different devices in this easy to comprehended white paper.

 

Conclusion to be “made” is that the effect of a power conditioner or the shielding of various devises may be hard to understand the importance of, if the measure is solely conducted in a lab without the normal interference they are made to reduce the effect from, but with them it’s much easier to see their effect.  

 

https://www.usb.org/sites/default/files/327216.pdf

 

 Even less well known is that RF/EMI from internal SSDs can  affect WiFi in close proximity, which has implications for Computer audio, and is why some may prefer HDD over SSD .Use of a PCI-e SSD could be even more degrading for Audio.

 I saw a link to a pdf about this, but unfortunately the link no longer works. IIRC, I passed the link on to Speedskater at the time

 Although the link no longer works it may assist in locating the information.

https://www.ieice.org/proceedings/EMC14/contents/pdf/14A2-B4.pdf

[sandyk]

12 minutes ago, mansr said:

Even if not, driving high-level ultrasonics into the tweeters burdens the amp for no benefit.

 

There were numerous reports in the initial days with SACD, of amplifiers being destroyed by ultrasonic garbage.

 Sony even sold 100KHZ tweeters back then too.

[sandyk]

8 hours ago, sandyk said:

Although the link no longer works it may assist in locating the information.

https://www.ieice.org/proceedings/EMC14/contents/pdf/14A2-B4.pdf

 

RF /EMI interference from SSD

 

Found it !  Also at : https://www.dropbox.com/s/c5unyq3dqvvg2gk/14A2-B4.pdf?dl=0

14A2-B4.pdf

[sandyk]

8 hours ago, Summit said:

 

It is correct that the switching noise generated by SSD can degrade SQ. There are special SSD filter and ferrites you can get to diminution their effect. SSD noise can also affect many other components besides Wi-Fi, which I don’t use more than to remotely control ROON.  

That does not mean that they are unable to outperform HDD with Audio.

In my case, I also have 2 SSDs mounted in the metal drive bays of my PC in aluminium carriers , and they use 2 separate  low noise regulated +5V supplies derived from the internal +12V rail, and are connected from the regulators which are mounted on the bottom metalwork of the PC via short screened PSU leads.

They are connected to the Motherboard using no longer than necessary screened SATA 6.0Gps A leads, not the generic 7 wires side by side type.

[sandyk]

43 minutes ago, Summit said:

I guess from your post that you think that one type of data storage is clearly better than the other, SQ vice.

I can get higher quality SQ from SSD than HDD due to the precautions I take. In this case the SSDs are also powered via very low noise +5V supplies which are not only also isolated from each other , but have far less interaction with the main +12V rail due to the voltage regulators. It's much harder to provide low noise power for an HDD due to the need to provide both +12V and +5V low noise PSUs for it.

 In my PC  one half of the PCB powers my OS SSD, and the other half powers an internal Music SSD with both powered from the +12V rail. To connect it, I use a 4 pin Molex to dual SATA power plug cable cut in half.

In addition, JRiver25  is set up to play from System Memory, which can easily be seen when playing from a USB memory stick where you can unplug it and the music continues.