[griff500]

I have heard of Hans, but respectfully I doubt at his age he can hear up to 16kHz - age will do that to all of us, that’s why when performance matters some careers force early retirement.

Reviewers should post hearing tests and be transparent about their physical capabilities; at least with professional athletes we can quantify this based on their stats. Needless to say, he’s on my ignore list. Might sound harsh but anyone with an opinion can start a YouTube channel or review a product which says nothing about their attributes - people should be more careful about these things into account before taking someone’s opinion - use common sense.

You might like to check the background of someone before putting them down?

I might expect someone with strong critical listening skills to be able to detect things that far younger people with less developed skills cannot detect. Somewhat like Phil Mickelson beating the young guns despite being old enough for the senior tour.

Your comment about hearing RFI and EMI makes it seem like you do not know what the impact of these actually is on the sound. I don't believe I have heard anyone saying they can hear RFI or EMI but you can certainly hear the difference when these are reduced.

 

[Triode User]

In preparation for Spotify Hifi I decided it was time to experiment with a raspberry pi streamer. My pi 4 is a compute board as I prefer ports on the back, no wifi, no bluetooth no eMMC memory running off a DC battery powerbank - I don't want to hear any arguments about electrical interference it's as basic as you can get.

A few questions I wanted to solve for myself:

1. Does the USB output impact the sound depending on the device?
2. Does the software renderer impact the sound?
3. Is there a difference in sound between USB and SPDIF?

My current chain is: MacBook Pro > Audirvana > USB > TT2
New chain is: RPi4 > Moode Audio > USB > TT2

Answers:

1. No. There was no audible difference between MacBook and RPi4 USB output using the same software. Audirvana sounded exactly the same whether I played it off my MacBook connected directly to the TT2 or streamed it from my MacBook to the pi and TT2 via USB.

2. Yes, Audirvana sounds different than moode audio. However, moode sounded exactly the same as Volumio which I later learned they both use MPD as the renderer - this supports my previous thesis about streamers, it's the audio renderer (ie. SOFTWARE) that is changing the sound. I have tested and confirmed this to be true in the past when comparing ROON, Audirvana and HQplayer on my MacBook.

3. Yes, but I was only able to compare TOSLINK and USB on my Mac. I have a digione on the way to compare digital outputs using the PI.

Other observations: I tried hqplayer embedded on the rpi (without upsampling) and it sounded the same as Audirvana.

What I can draw from this, the software renderer matters, the output to the TT2 matters, but the same output (USB) on two different devices using the same renderer made no difference. The investment is small and you can easily replicate these tests on your own.

Hmmn, well you seem to have ruffled a few feathers with your later posts but just on this one of your listening tests indicating to you that the hardware is not important for a renderer and that it is only the software that matters I must respectfully disagree.

I note that to you "Audirvana sounded exactly the same whether I played it off my MacBook connected directly to the TT2 or streamed it from my MacBook to the pi and TT2 via USB." This is not a full proof that the hardware does not matter, merely that the hardware versions you tried had no difference to your ears and in your system.

One example I have personally listened to is the Innuos range where it is easy to use the same software throughout and to listen to the various models in the range and I can tell you that they all sound different. In some cases very different.

I don’t believe you or Hans can hear EMI or RFI that might be emanating from an Ethernet cable.

Just on this one and without it appearing that I have a one track mind about Innuos, I recently listened to their PhoenixNET switch and compared it to another well known 'audiophile' switch against a reference of pulling the ethernet cable from the back of the streamer. If I had only listened to the PhoenixNET switch compared to disconnecting the ethernet cable I might have concluded that the switch makes no difference because I could not hear any difference between them. However by adding the alternative switch into the comparison I very clearly heard a difference in sound between using that switch and pulling the ethernet cable from the back of the streamer.

Mind you, my ears (and brain) are more than 65 years old.

In order to protect the guilty I will not mention that other switch's name.

 

[alekc]

Hans is a good guy, taking the time to explain concepts and technologies to perhaps a less clued in audience.
Hans also worked as a professional in recording studios I think.
Hans is a giver, but your recent posts make you sound a little arrogant.
to choose between listening to a decent guy who contributes to the community or an arrogant guy, I know which I’d choose.

and further, robs an older man, does that mean we rubbish his hearing opinions.
listening is a skill, although I imagine you mostly exercise speaking !

It is hard not to agree with what you have written... with one small exception: he is making money out of it. If you take money out of the picture it all looks great. If you approach to it from business perspective it changes a lot, especially for particular products where true effects are very controversial to put it in a very gentle and diplomatic way. Personally I disagree with some of his opinions, and I am completely fine with that. However in some cases it is hard for me to accept that source of our different opinion is solely (his) better hearing and not marketing. I have nothing against him personally, I also do not follow Darko for the very same reasons for example. I prefer reviewers who vote using their money earn outside of audio industry. Obviously everyone can have own point of view and this is completely fine. The one thing I and probably we all agree on is following phrase: enjoy the music!

 

[Articnoise]

Before spending on a power supply try this. While listening remove the dc jack from the back of TT2. You should have 30 seconds running from the super caps. If it sounds better then look at a different supply/battery. If it sounds the same spend your $ on some new headphones.

Did it sound the same to you?

This type of testes have been used to prove a point that is IMO built on incorrect premises, namely that all the disturbances would disappear immediately if you just unplug the cable or the power cable. Yes, it is true that some disturbances (noise) are of that kind that stops immediately, but much is about creating stable conditions for the circuits to work as good as possible. HIFI is very much about creating the right temperature, voltage, etc. by eliminating things that affect them negatively. Different kind of noise is bad, as is fluctuation in volts which causes huge problems for many digital and electrical circuits, like clocks, because they prevent them to be able to work in their best way and under best conditions.

The most important thing to know is that the actual digital to analog conversion takes place because of tiny differences in volts. It can therefore often takes a few minutes (at least) before many circuits have reached an electrical/temperature stability and the more stable the better many sensitive circuits can function.

Audio resolution is measured in bits. Audio resolution is often expressed and understand as bit depth. A 16-bit recording has 65,536 steps, a 20-bit recording has 1,048,576 steps, and a 24-bit recording has 16,777,216 steps. For each step, it’s a clear reduce in amount of voltage so the higher the resolution the lower the voltage. This mean that the digital to analogue conversion has to be able to detect very, very small signals of ± less than 1µV (1 V = 1000000 µV).

Another completely different but important reason is that the noise pollution can get into the ground plane where it, so to speak, travels around between our devices for long time. A third reason is leakage current and how even very small amounts affect sensitive circuits negatively.

 

[Articnoise]

I was about to post this but didn't because some people in this thread have the money, like to tinker and able to convince themselves it makes a difference when in reality there is none - now I sound negative but someone has to debunk some of this crap. Rob has designed the TT2 to filter the power and run off the super caps, someone could have a grounding issue but that's easily solved for a lot less than the cost of a power supply and Rob has already indicated that earlier in the thread.

Have you tested this yourself? I have and a good power conditioner and/or PSU does make a great improvement in SQ with the TT2 and that's what's important to me.

Maybe it's the opposite and it's you that try to convince yourselves that is no difference, This without listen first. Yes you need to use a really good PSU to get better sound than with the stock PSU.

 

[Arnold Schwartz]

I’ve said it before, Chord, Sennheiser, Focal and companies of the like employ engineers and spend tons to develop products that are extensively researched and tested - imagine how complex the endeavour is to develop the TT2 or Dave? It took Rob a lifetime to gain enough experience to develop these products. And then some hobbiest thinks a simple cable or power supply makes all the difference l. It’s no wonder though, almost anyone can make a cable or LPS power supply with some basic knowledge, so I expect there are people wanting to provide these products with unsubstantiated claims, especially since this hobby is filled with people that want to get “closer to the music” and willing to spend a few hundred easily on garbage. Because I hear it is not a good enough explanation, you might have poor hearing, you have an expectation bias, the change is measurable but not audible.

Rob has already shared with us the power supply that came with the TT2 is the best option. Rob has already said he tested many different power supplies. Rob already designed a product to run off clean power using supercaps, Rob already said not to use LPS power supply - do you trust your ears over what Rob Watts is telling us?

Maybe you would like to believe in an improvement so you hear one and yes it’s real to you but it’s unlikely to be real. It’s such a taboo in the audio world to challenge these opinions but someone needs to say it because it needs to stop.

 

[Gadget67]

I’ve said it before, Chord, Sennheiser, Focal and companies of the like employ engineers and spend tons to develop products that are extensively researched and tested - imagine how complex the endeavour is to develop the TT2 or Dave? It took Rob a lifetime to gain enough experience to develop these products. And then some hobbiest thinks a simple cable or power supply makes all the difference l. It’s no wonder though, almost anyone can make a cable or LPS power supply with some basic knowledge, so I expect there are people wanting to provide these products with unsubstantiated claims, especially since this hobby is filled with people that want to get “closer to the music” and willing to spend a few hundred easily on garbage. Because I hear it is not a good enough explanation, you might have poor hearing, you have an expectation bias, the change is measurable but not audible.

Rob has already shared with us the power supply that came with the TT2 is the best option. Rob has already said he tested many different power supplies. Rob already designed a product to run off clean power using supercaps, Rob already said not to use LPS power supply - do you trust your ears over what Rob Watts is telling us?

Maybe you would like to believe in an improvement so you hear one and yes it’s real to you but it’s unlikely to be real. It’s such a taboo in the audio world to challenge these opinions but someone needs to say it because it needs to stop.

Well, I most certainly agree that companies do spend lots of money to deliver the best possible product, but please realize these companies are also “price point” conscious. For example, the PSU for both the TT2 and M-Scaler is very adequate for 90+% of users, many of whom are not rabid audiophiles. If Chord were to sell the TT2 with a “better” PSU that cost hundreds more for a “minor” improvement I can almost guarantee that sales would go down significantly. Many here would rather buy what I’ll call a good “starter” device and tinker with it to extract the sound they seek. I’m not going to engage in a debate about what is “better” since that is very dependent on user preferences. In my case I spent a not insignificant amount on power cords, power management and (in the case of my M-Scaler) “better” BNC cables, battery power and optical cables to give me the sound I wanted. Chord wouldn’t be able to provide these additional “enhancements” because many are very user specific and, obviously, expensive.

Now, as to whether or not these are distinguishable improvements is an open question to many. In my case my non-audiophile wife is one of my reference points. She has mediocre hearing, hates headphone generally and is not nearly as attuned to changes in my set up as I believe I am. I don’t share what changes I make but instead let her offer an unvarnished opinion. She noticed the power management changes and the switch to battery power with the M-Scaler when listening to our 2.1 system. I can cite other examples but when she notices, I know there is a difference…not scientific, but it works for me.

Lastly (for now) realize we all hear things differently; what happens between the point when sound enters my ear and reaches my brain is subject to many unverifiable variables. This brief article from the NIH may help you understand that:

https://www.nidcd.nih.gov/health/how-do-we-hear

I respect and understand that you have strong opinions about all of this; the rest of us do as well. I value your opinion and ask that you extend others the same courtesy.

 

[MarkusBarkus]

It’s such a taboo in the audio world to challenge these opinions but someone needs to say it because it needs to stop.

...wouldn't that door swing both ways? Is *any* designer or product so perfect that it/he cannot be challenged?

 

[Triode User]

do you trust your ears over what Rob Watts is telling us?

Well, sometimes yes. And on the occasion I am thinking of Rob was gracious enough to concede the point.

 

[bpcans]

Well, sometimes yes. And on the occasion I am thinking of Rob was gracious enough to concede the point.

Triode User, I’ve always thought that Rob Watts was exceedingly patient and gracious with those of us who not only enjoy the fruits of his many years of research, but who also desire to know more about how his designs work, even though most times he’s talking in a technical manner which is way beyond my comprehension. What really brings me lots of joy are moments like now when I’m able to listen to a recording of the Benny Golson Sextet from December in 1957, and the music sounds as if I’m actually sitting in the studio. Which is kinda weird if you think about it. Stereo and hi-fi have come so far just in my lifetime that it’s almost amazing. My grandmother had a Victrola in her parlor where she played 78rpm records from the roaring 20’s, 30’s, and the 40’s. She would freak out if she heard what‘s available now.

 

[Lgn3]

Well, I most certainly agree that companies do spend lots of money to deliver the best possible product, but please realize these companies are also “price point” conscious. For example, the PSU for both the TT2 and M-Scaler is very adequate for 90+% of users, many of whom are not rabid audiophiles. If Chord were to sell the TT2 with a “better” PSU that cost hundreds more for a “minor” improvement I can almost guarantee that sales would go down significantly. Many here would rather buy what I’ll call a good “starter” device and tinker with it to extract the sound they seek. I’m not going to engage in a debate about what is “better” since that is very dependent on user preferences. In my case I spent a not insignificant amount on power cords, power management and (in the case of my M-Scaler) “better” BNC cables, battery power and optical cables to give me the sound I wanted. Chord wouldn’t be able to provide these additional “enhancements” because many are very user specific and, obviously, expensive.

Now, as to whether or not these are distinguishable improvements is an open question to many. In my case my non-audiophile wife is one of my reference points. She has mediocre hearing, hates headphone generally and is not nearly as attuned to changes in my set up as I believe I am. I don’t share what changes I make but instead let her offer an unvarnished opinion. She noticed the power management changes and the switch to battery power with the M-Scaler when listening to our 2.1 system. I can cite other examples but when she notices, I know there is a difference…not scientific, but it works for me.

Lastly (for now) realize we all hear things differently; what happens between the point when sound enters my ear and reaches my brain is subject to many unverifiable variables. This brief article from the NIH may help you understand that:

https://www.nidcd.nih.gov/health/how-do-we-hear

I respect and understand that you have strong opinions about all of this; the rest of us do as well. I value your opinion and ask that you extend others the same courtesy.

Depending on how you define the phrase rabid audiophile I would suggest you would have to be one to have even heard of TT2/HMS let alone be prepared to spend the best part of £8k to purchase that equipment.

 

[muski]

I’ve said it before, Chord, Sennheiser, Focal and companies of the like employ engineers and spend tons to develop products that are extensively researched and tested - imagine how complex the endeavour is to develop the TT2 or Dave? It took Rob a lifetime to gain enough experience to develop these products. And then some hobbiest thinks a simple cable or power supply makes all the difference l. It’s no wonder though, almost anyone can make a cable or LPS power supply with some basic knowledge, so I expect there are people wanting to provide these products with unsubstantiated claims, especially since this hobby is filled with people that want to get “closer to the music” and willing to spend a few hundred easily on garbage. Because I hear it is not a good enough explanation, you might have poor hearing, you have an expectation bias, the change is measurable but not audible.

Rob has already shared with us the power supply that came with the TT2 is the best option. Rob has already said he tested many different power supplies. Rob already designed a product to run off clean power using supercaps, Rob already said not to use LPS power supply - do you trust your ears over what Rob Watts is telling us?

Maybe you would like to believe in an improvement so you hear one and yes it’s real to you but it’s unlikely to be real. It’s such a taboo in the audio world to challenge these opinions but someone needs to say it because it needs to stop.

Just curious, is English your first language?

 

[Rob Watts]

...wouldn't that door swing both ways? Is *any* designer or product so perfect that it/he cannot be challenged?

No one is perfect; we are all human, and knowledge is imperfect. But I accept that my understanding is limited and subject to error; but I also understand that my knowledge is improved by new evidence and more understanding of the underlying issues, and my time is spent in actively testing and sometimes re-testing my assumptions, as this is the only way that true progress is made. Moreover, posters comments when using my designs has in the past been a fantastic resource in discovering new issues, which when researched led to better designs, in turn allowing me to enjoy music more.

But that door does indeed swing both ways - you have the right to challenge my understanding, but I have the right to challenge yours too. In the case of LPS on TT2, the subjective evidence is strong that a LPS will only ever degrade the sound quality (or at best sound identical) to the stock PSU. So when I had removed the PSU (you can do this for 10 seconds) there is no change in sound quality. Using a battery (the ideal PSU from random RF noise) for extended periods also elicited no change in sound quality. Of course, this is with my system, and your mileage may vary. But I can only go on my direct experience.

Theory also backs up my position; random RF noise (note random, not switching noise) creates noise floor modulation which is measurable. That is a fact. My observations are that noise floor modulation (however small) makes the sound brighter and degrades instrument separation and focus; moreover it can etch the sound quality, giving a false sense of transparency. As an engineer, when I look at audiophile LPS designs I recoil in horror; large leaded components with huge RF resonances, huge toroidal transformers with enormous coupling capacitance; large levels of stray electromagnetic noise. These things are guaranteed to pass random RF noise from the mains straight through to the TT2, unlike the SMPS with it's low capacitance transformers, and input and output RF filters, which actively reduce random RF noise.

But I must admit to a failure on my part; I design my gear with certain PSUs in mind, and that I get no improvements from using truly better PSUs - job done. What I should have done was to use a great deal more RF filtering so that when you connect a crappy random RF noise source (sorry I meant to say LPS) you would hear no difference then there would be no argument about "better" PSUs. But then you might not like the SQ of TT2, but then that's your choice.

Triode User, I’ve always thought that Rob Watts was exceedingly patient and gracious with those of us who not only enjoy the fruits of his many years of research, but who also desire to know more about how his designs work, even though most times he’s talking in a technical manner which is way beyond my comprehension. What really brings me lots of joy are moments like now when I’m able to listen to a recording of the Benny Golson Sextet from December in 1957, and the music sounds as if I’m actually sitting in the studio. Which is kinda weird if you think about it. Stereo and hi-fi have come so far just in my lifetime that it’s almost amazing. My grandmother had a Victrola in her parlor where she played 78rpm records from the roaring 20’s, 30’s, and the 40’s. She would freak out if she heard what‘s available now.

Sorry if you have trouble understanding some of my posts; I try to make it as simple as possible, but you can't make it too simple otherwise you are failing to communicate the technicalities - and I am writing to a very diverse audience, from little technical knowledge to experts. And some of the concepts I have trouble fully understanding - as they are complex - one of the benefits of trying to explain something is that you expose your own weakness in logic, so it ends up making more sense to yourself by trying to explain it!

I too get tremendous musical pleasure from old recordings. And its very humbling when I make a major advance in sound quality, only to discover recordings that I had dismissed as bad were not so bad after all! Then I beat myself up for being so dumb that I had not achieved the improvement earlier...

 

[Articnoise]

But that door does indeed swing both ways - you have the right to challenge my understanding, but I have the right to challenge yours too. In the case of LPS on TT2, the subjective evidence is strong that a LPS will only ever degrade the sound quality (or at best sound identical) to the stock PSU. So when I had removed the PSU (you can do this for 10 seconds) there is no change in sound quality. Using a battery (the ideal PSU from random RF noise) for extended periods also elicited no change in sound quality. Of course, this is with my system, and your mileage may vary. But I can only go on my direct experience.

I would like to take part of those subjective evidence that a good LPS will degrade the sound quality. In my experience the stock PSU (from Mean Well) sound brighter and degrades instrument separation and focus compared to a good LPS. This is not limited to TT2 and I hear the same SQ difference with my EtherREGEN and NUC, which all came with a power supply from Mean Well. As I stated before the Mean Well is not bad, and especially not for how inexpensive it is, it's just not as good as a really good PSU IMHO. To me changing PSU makes the TT2 a clearly better sounding DAC and that is terrific that we have that option in my book.

Jay Luong (Audio bacon)
"In essence, a better power supply will sonically “align” the complex analog and digital signal into something that’s properly outlined and shaped. This alignment is responsible for the tighter lines and an overall more insightful listening experience. Without a proper power supply, there are “gaps” and “jumps” in the sound.
Simply put: Music is less artificial, less rough, and more live."

https://audiobacon.net/2018/06/29/linear-power-supplies-for-audiophiles-getting-closer-to-live/

Rajiv a.k.a. Austinpop​

“The Farad Super 3, in addition to being an excellent PSU as I found in my previous report, has the added advantage of a continuous current capacity of 3A. This puts it in a unique position compared to lower powered supplies like the LPS-1.2 and the SR-4. The field of high-quality PSUs with current capacity over 2A is quite limited, and the Farad is a welcome addition. I can see it being a great fit for DACs, and other current-hungry devices like NUCs. For my use case of powering a Chord Hugo TT2, the Farad Super 3 was not only up to the task, its SQ while doing so was excellent." Read all about it here.

https://faradpowersupplies.com/shop/en/content/13-testimonials

 

[Lgn3]

Jay Luong (Audio bacon)
"In essence, a better power supply will sonically “align” the complex analog and digital signal into something that’s properly outlined and shaped. This alignment is responsible for the tighter lines and an overall more insightful listening experience. Without a proper power supply, there are “gaps” and “jumps” in the sound.
Simply put: Music is less artificial, less rough, and more live."

https://audiobacon.net/2018/06/29/linear-power-supplies-for-audiophiles-getting-closer-to-live/

​

What on earth does that mean ?