Topping and SMSL with ASR Punking Us on DACs?

Thor, if I may ask, I read that somewhere that for the ifi Pro IDSD dac, initially it supports 48k base DSD sample rate decoding but after a later firmware update, it does not do 48k base DSD properly anymore. Is that true and is there a way to somehow revert back to previous firmware version so it would work?

Cheers

Deric

 

Did they actually put that they banned you for racism anywhere in writing? Ironically, the reason they gave you in the attached screenshot is very nebulous and could be seen as a prime example of intolerance.

I followed your comments on ASR with great interest and did not realize that you were banned.

 

I could be described as a "Chinese engineer" because I'm an engineer and of Chinese descent. However I was born and lived my entire life in the US, so I don't know whether that makes me an American engineer or a Chinese engineer. It isn't so difficult to understand why your comment might be interpreted as racist.

 

It is important to distinguish between opportunistic companies, such as Topping, requiring their engineers to design for an abhorrent design goal set by self-serving, self-absorbed appliance operators and those truly exploring the boundaries of what is possible, such as Jeff Zhu, Holo Audio, who is also Chinese and an extraordinary designer.

 

Have you read the threads that lead up to that statement? It would provide more context, it isn't anything that is out of line, and has been discussed here before.

 

ASIO DSD never supports 48k base, this is down to the driver and to Steinbergs specification, which is ancient. It is possible that some driver versions enabled 48k base DSD over ASIO.

DoP DSD supports 48kHz base DSD>

In both hardware and firmware the iDSD Pro should always support 48k base DSD.

Thor

 

No, one morning I woke up to this screen. However before that several people at moderator levels had deleted posts ans stated in the thread that what I wrote/had written was "underhanded racism". However, after I got banned (without any particular reason given) whole threads disappeared.

Perhaps I was not banned for racism - but instead for upsetting the apple-cart and the revenue extraction from chinese hifi makers and pay-trons instead?

Thor

 

Well, my use of "chinese engineer" is:

"mainland educated and only mainland work experience Engineer without any or extremely limited english"

In other words it is a citizenship/locality based definition, not an ethnic one.

Many taiwanese or hong kong engineers who are ethnically chinese are excellent, no doubt also those ethnic chinese living and having grown up Europe or north america.

I am not suggesting that ethnically chinese people are in any way deficient in anything, rather the mainland chinese education system and also working conditions are a cause for the limitations chinese engineers (not just electronic) display. Ethnically the "chinese engineer" may very well be not chinese at all, but a Mongolian from inner Mongolia, a Kyrgyz or Tajik, an Uyghur, Tibetan, Miao or other ethnic minority in Mainland china.

However "mainland educated and only mainland work experience Engineer without any or extremely limited english" is a bit of a mouth full, so commonly I shorten it to "chinese engineer", especially if the context should make the meaning clear.

Thor

 

Not all Engineers in China are bad, however, compared to Europe and North America, the "average chinese "electronic engineer" with a degree from a good university is less competent than a non-degreed electronic technician in Europe and North America.

The education system in china focuses on rote repetition, not understanding. And once in the workforce in China, most companies focus on copies or simply design by copying circuits from the datasheet.

This means from my experience, many electronic engineers you may meet in China will not be to carry out most basic electronic calculations, cannot use circuit simulators and do not even understand that parts with the same nominal rating and value or mostly the same part number IS NOT EQUIVALENT.

I also noted that the what I consider basic reading comprehension for technical documents like datasheets (written by chinese engineers in chinese!) is poor. And these is no Initiative or will to change and improve their abilities.

Note, they are not stupid or lazy people, they just received an education and life long conditioning that did not develop their abilities in the way western education does. Our academic education focuses on enabling our Masters and above degree holders to able to do individual, unique and new work, create new systems and ideas.

It's a failure of the chinese educational system. Naturally ethnic chinese that learned in the western education system are very different. However, few ethnic chinese who studied abroad or grew up abroad return to china to work there, so the best and brightest go elsewhere.

Of course, not ALL EE's in china are like that, there are exceptions.

But they usually end up in large state owned enterprises often in the Military Industrial complex. Some of those after retiring or switching track may start audio companies. I met few such individuals in China. But they are very rare. I was never able to get one hired on the chinese side.

Thor

 

Hi Thor, the IFI IDSD PRO Signature, as an upgrade to the original IDSD PRO, includes the iPower Elite power supply as an upgrade to the original iPower Plus. Do you mind commenting on how susceptible is the IDSD PRO DAC be impacted by PSU noise and whether the iPower Elite is a real performance upgrade from the iPower Plus? I have also owned an iPower and an iPower X in the past when I used to own the ifI NEO IDSD and always wonder if it makes much real impact to a DAC or perhaps to the headphone amp of the dac, or streamer/network endpoint...?

I have also come across reading some of the medical grade switching power supply that is measured to be extremely low in noise and current leakage. Is there any real benefit to using the iPower series of PSU versus of one of these medical grade PSU?

Thanks

Deric

 

The "iPower Elite" is ~ 90%+ the same as the inside of the iPower Plus in a fancy box. There is in my opinion no performance benefit, except possibly better shielding from a metal case, over a plastic case.

Ifi have been doing this with their other SMPS also, put pretty much the same electronics in a fancy case and jack up the price. A lot.

The original iPower & iPower Plus already (in my view) pushed the price, at least on "fair price", the newer version cannot be recommended on Value for Money.

The Elite costs 300 Euro, for similar money you get an SBooster linear PSU. Not saying SBooster is necessarily better, but they put a lot of stuff that costs real money inside a cheap plastic box.

Compared to that the iPower Elite puts a lot of extremely cheap stuff into a slightly fancy metal case.

The original "Plus" put pretty much the same internals into a cheap plastic box and sold for under 100 Euro. That made it a bargain next to Sbooster, at 1/3rd of the price.

The "Pro" series all use "dual conversion (including the iESL).

Here a picture of the PSU, you can "read along":



All incoming DC passes through a symmetrical "PI" LC filter, the two black things marked ifi 220 (22uH each) on the far right side of the shown PCB.

Then a dedicated step down converter IC (3A) with 1.2MHz switching frequency produces a "raw" 6V Rail for the Tube heater (U201 + L203).

Another step down converter IC (8A) with 1.2MHz switching frequency produces a "raw" 5.5V / 8A (44W max) Bus for all digital and analogue circuits (U200 + L201).

Digital power supplies are derived from this 5.5V via a large inductor and a pair of Elna "Dynacap" Super Capacitors giving an effective 1,650,000uF power supply capacitor for the digital circuits (parts on the main PCB).

A total of six switching regulators (Left/Right +/- 12V [iDSD] or +/-16V [iCAN] & Left Right +48V) also running at 1.2MHz create the analogue stage voltages from the 5.5V "Bus". These are the IC's and inductors on the left hand bottom.

All power supplies use 1210 format ceramic capacitors that are effective at 1.2MHz for filtering and have additional bypass capacitors and are followed by LC filters on the Power supply PCB (the inductors on the left hand upper section, capacitors are below the PCB.

The main PCB contains additional LC filters and electrolytic capacitors that are selected for their specific value and ESR to result in a critically damped 4th order LC filter to remove power supply noise. As all power supply noise is at 1.2MHz and higher, they have zero effect at the actual noise frequencies. Due to the power supplies using regulation and having very low output impedance, these capacitors also have no effect at audio frequencies, as the regulator output impedance is much lower than the impedance of these capacitors.

It appears a major "improvement" on the "signature" edition was to replace the original "low grade" capacitors (selected because they give the correct dampling of the power supply filter) with "high grade" types that would change the damping of the power supply LC filters unpredictably. They still have no effect either at the actual power supply noise frequencies or for audio.

As you can see, any power supply noise to make it through from the DC input has to overcome multiple stages of LC filtering and two separate switching regulators. In testing it was not possible to get any noise from input to output.

Of course, any common mode noise from the power supply will be conducted more or less well (the LC filter does help some) into the audio ground.

The Neo was designed as "budget" product for a 300 USD price tag.

As a result it's power supply system is more simple. However, it still uses single sages of switching converters (to create +/-5.7V for the analogue circuit) and other switching and linear regulators to derive all power supply voltages, again multiple levels of LC filtering are used.

Again, the chance of conducting noise on the power supply lines all the way through the power supplies to something they supply is quite low. Of course, again any common mode noise from the power supply will be conducted into the audio ground.

If you go one more step down to the "Zen DAC", there the Headphone Amp run's directly from the USB/External power and there is just an LC filter to filter power to the analogue stage. So this design will show some notable sensitivity to power quality.

In principle, any SMPS that is contentiously and consciously designed to offer both low noise and and low leakage current / low coupling capacitance to mains should be a good choice.

While the "output noise" measure makes for good marketing copy (the iPowers super low noise exists only for marketing copy and is NOT necessary, technically speaking), in reality competent design should deliver noise low enough in practice.

There is no real way (well, there is, ANC as I use for iFi) to deal with switching noise actively in a standard SMPS, so there needs to be enough LC filtering on the input and output side to lower noise to whatever is considered acceptable.

As audio circuits commonly have less supply noise rejection at higher frequencies, we want this noise really low. I think -100dBV ( 10uV switching noise) should be ok under all conditions.

Another factor is the size of the input reservoir capacitor, it needs to be large enough to keep the actual switching regulator "in regulation" at the currents you use, or you will get 100Hz noise (hum) breakthrough.

Finally, an optimum design around the TL431 error amplifier (common in almost all off mains SMPS) will give around 3uV/V output noise, so a 5V DC output should have ~ 15uV noise across the audio band, which is -97dBV.

I think this performance (which you would get from an iFi power supply without the ANC module) is sufficient to be fine for almost any audio use.

As said, more critical is really the coupling capacitance between mains and output. This is not specified anywhere, leakage current is a proxy for this, but not necessarily directly proportional.

Thor

 

Do that thing rich businesspeople here do and have a conspicuously placed smartphone in a breast pocket with the camera peeking over the brim to make anyone you pass by think they're being recorded and broadcasted in real time to deter shenanigans.

 

Could not agree more with the above re: ASR favorable treatment for Topping and SMSL... pains me to see occasionally ppl posted their love for ifi dacs over those brands received brutal attacks on the forum...

Or they accuse you as some kind of strange animals for having a preference in DSD playback over PCM......

 

I think this is what pisses me off the most - the fact that people who are questioning the official mantra AND are perceived as carrying a potential threat to that ideology are inevitably banned there. I could accept that forum protecting the reps of the companies that they are unofficially affiliated with, I could accept the skewed reviews that seem to contradict the basic premise of their own argument (that $99 DAC is all you need, basically), but I cannot stand it when legitimate people with experience and credentials are being cancelled and banned from participating in discussions.

This leads me to a question for anyone here that may have a legal background - can a moderator on a public online forum ban any user for any reason? Do they have to disclose the reason to the user? What kind of proof do they need to have?

As an extreme example, say that a moderator bans people that he/she suspects belong to a specific minority group (based on their name/last name). If someone could prove that there is a case of ethnic/racial discrimination, would they have any legal recourse against the forum/moderator?

 

I believe Miska - Hqplayer was also banned from ASR for his opinion on DSD as well.

Judging on the pedigree/credentials of some of the ppl being banned on ASR, it almost feels like an honour to be banned!!

 

The owner/administrator of a forum can ban anyone for any reason or no reason at all. A forum while allowing public discourse is a private entity (unless it's government funded) and therefore "get off my lawn" is as legal as saying so to someone on your own physical property.

Transparency: I'm not a lawyer.

 

Fun & learning what not to say.

 

Amir has to play 3d chess with one eye because the other is a sending stone connected to the CCP.

 

I'm willing to give Amir the benefit of the doubt. He probably means really well and thinks his prejudices and beliefs are fact.

And I think he is really doing a great service to the poor pee-pull and everyone who disagrees with him only does so because they sell things according to a false system of belief that has been foisted onto the poor pee-pull who are all idiots and don't know better and need to be re-educated (forcibly if need be) to his belief system for their own good.

Never mind he doesn't even know how to properly operate the gear he uses for measurements and cannot tell real problems from interactions with the limitations and foibles of his equipment

Of course, that is ultimate hubris and it is a reason that no argument will ever connect with Amir, no matter how well reasoned. If there is any danger of such a case, goalposts are quickly moved.

He kind of reminds me of a more commercially successful version of the ABX Mafia (Clark, Krueger et al) who has not yet been exposed as Cargo Cult Scientist and hence if not really a bitter spoilsport, though no doubt this will come. Karma's a B!tch.

It is worth looking a bit into Amir's background and what he made his big money with and where his expertise lies (it's all in the public domain).

Thor