Features wanted in a Wiim Ultra 2

Just wanted to let you guys know that the RCA to XLR cables from Benchmark work perfectly for connecting WiiM Ultra to Topping B200 monoblocs (which have no single-ended inputs).

Specifically these cables:
 
Just wanted to let you guys know that the RCA to XLR cables from Benchmark work perfectly for connecting WiiM Ultra to Topping B200 monoblocs (which have no single-ended inputs).

Specifically these cables:

Pretty much any RCA to XLR adapter will do. I got some simple adapters and some of these cables ( I like Canare and Belden ). Now, I don't make any money from these people, but I've been buying their cables for quite a while.


HOWVER, be aware that you're still not quite driving the amp with the full dynamic voltage swing of a true balanced connection. Depending on the gain of the amp you might need that.

Ideally an active converter is desired... at least a transformer.

 
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Pretty much any RCA to XLR adapter will do. I got some simple adapters and some of these cables ( I like Canare and Belden ). Now, I don't make any money from these people, but I've been buying their cables for quite a while.


HOWVER, be aware that you're still not quite driving the amp with the full dynamic voltage swing of a true balanced connection. Depending on the gain of the amp you might need that.

Ideally an active converter is desired... at least a transformer.

Yes, the amps (a pair of Topping B200 monoblocs) have two gain settings. I am first trying it out on Low Gain (~+11dB); I know the vast majority of my music will be more than loud enough, but I have to test reference level tomorrow morning on my quietest/most dynamic tracks to know for sure if Low Gain is enough. I can’t test it right now as my kids have already gone to sleep and their room is directly above my speakers, so every night I lose access to reference levels around 8pm.

Otherwise, I already tested High Gain (~+21dB gain) earlier this evening when the kids were still awake and it is absolutely loud enough, even with ReplayGain enabled. I probably should have done it the other way around knowing that I can’t test reference level later this evening.

-Ed
 
....

Pass makes no statement implying that listening alone could be useful in developing an amplifier (or any other piece of kit). Instead, the article mostly explains in terms of simulations and measurements the effects of non-linearities concerning the input signal (explicitly leaving othe non-linearities aside).

All the graphs show data for zero feedback scenarios, only. To learn more about why negative feedback is so helpful (and so misunderstood), here is a slightly more recent article by the best known developer of the most accurate class-D amplifiers in the world, Bruno Putzeys (Phillips, Hypex, Purifi, Kii Audio, ...):


True.

I've read Bruno extensively too... good reads. He also listens.

It is true that our current measurement techniques do not quite explain what we hear. At least we don't know all of it.

IMHO, the FCC standard of quoting power at a given THD is incomplete nowadays, since we now know that not all orders of harmonic distortion have the SAME effect on our perception. We can tolerate a lot of 2nd order but very little 3rd, and 4th yikes. Two amps with the same power rating, one with 1% of 2nd THD and the other with 3rd THD will sound extremely different. Why? Well, we don't know why, we JUST know. So, the ratings should reflect the harmonic distortion spectrum...

Eg:

25 watts into 8 ohms from 20-20Khz with HD at (0.5 / 0.1 / 0.0005 / 0.000001 )% where we define the harmonic distortion at the 2nd, 3rd, 4th and 5th. Nevermind whether it's positive or negative....

Indeed, a little bit of negative 2nd order harmonic distortion, aka "the sugar" makes things sound better. Go listen to a bridged amp, with very low 2nd harmonic distortion and you note how "lean" it sounds. First Watt's SIT1 actually had knob to adjust this. In some of my amps I've thought about specifying such a knob in the front panel.

I think what separates Pass from many is that he knows from experience how to achieve a given sound by design. He purposely "voices" his amplifiers to sound good not to measure good. He's also a funny guy... but then, he is at heart a physicist that likes red wine.

Bruno is there too. He knows how to create a sound he wants. In his case he goes for very low distortion, extremely low output impedance and the resulting very high damping factor. Getting away from an integrating output filter.

What's fascinating is how Pass is old school linear mathematics while Putzeys uses numerical analysis.

Both are fun to read...



While we're at it...

What I really want is a homogenous WiiM Home that operates equally across all hosting platforms.
 
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Just wanted to let you guys know that the RCA to XLR cables from Benchmark work perfectly for connecting WiiM Ultra to Topping B200 monoblocs (which have no single-ended inputs).

Specifically these cables:

I wouldn't use XLR to RCA though
 
Many (?) see this machine not just as a streamer but as an "all-in-one" preamp...


""""I'd have liked slightly bigger screen, IR receiver"""
That doesn't seem very useful to me either.
;-)

IR receiver is useful if you have a universal remote, I can also re-use my Logitech Squeezebox remote, if that allowed direct command instead of unlocking phone loading wiim app, navigating menus etc
 
Unfortunately, the perception of individual listeners (even if they feel like they represent a majority, which is never the case) is nothing any developer in their right mind could make any sense of.
Nobody is asking designers to be mind readers. They are expected, however, to be talented enough to design a better sounding product within a specific budget. Designing solely to satisfy a few measurement graphs is insufficient as they need to be mindful of all factors that affect what we actually hear. Real world development should involve tuning and broader workgroups to assess sound quality.

It’s also more accurate to speak of hardware designers or engineers rather than 'developers,' a term usually reserved for software. There is a clear difference in expertise when it comes to component selection and architecture. This is evident in the general consensus found online where multiple sources and users agree that the MXN10 outperforms the WiiM Ultra in perceived sound quality. The pattern is too consistent to ignore.
 
They are expected, however, to be talented enough to design a better sounding product within a specific budget. Designing solely to satisfy a few measurement graphs is insufficient as they need to be mindful of all factors that affect what we actually hear.
I cannot remember having stated the opposite.

It’s also more accurate to speak of hardware designers or engineers rather than 'developers,' a term usually reserved for software.
You're ignoring the fact that in digital network devices with DSP software determines the sound quality at least as much as hardware. It might be very convenient to ask for "better output stages", hand picked (or rather ear picked) opamps, "linear power supplies" (because linear is always better than non-linear) and "less noise" without specifying what that means apart from "better sounding". But that's simply not how development works. Consequentially, the term developer is totally appropriate in my book.

The correlation between measurements and listening impression can certainly be more complex than some may think. Dealing with it can in part be individual experience or grey knowledge. But as soon as we want make use of listening impressions in more than an anecdotal way we're back in measuring territory. There are well known psychometric methods that can take the uncertainty out of human perception. But this only works in controlled environments.

This is evident in the general consensus found online where multiple sources and users agree that the MXN10 outperforms the WiiM Ultra in perceived sound quality. The pattern is too consistent to ignore.
This online "consensus" not only can but must be ignored by PD, it's input for marketing, at best. Can you name at least one controlled blind ABX test supporting your theory of the WiiM Ultra sounding inferior?
 
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IMHO, the FCC standard of quoting power at a given THD is incomplete nowadays, since we now know that not all orders of harmonic distortion have the SAME effect on our perception. We can tolerate a lot of 2nd order but very little 3rd, and 4th yikes. Two amps with the same power rating, one with 1% of 2nd THD and the other with 3rd THD will sound extremely different. Why? Well, we don't know why, we JUST know. So, the ratings should reflect the harmonic distortion spectrum...

Interestingly, i don't see this in conformance with what Nelson pass said.
Nelson Pass said:
Many audiophiles believe that 2nd harmonic is to be preferred over 3rd harmonic. Certainly it is simpler in character, and it is well agreed that orders higher than third are more audible and less musical. However when given a choice between the sound of an amplifier whose characteristic is dominantly 2nd harmonic versus 3rd harmonic, a good percentage of listeners choose the 3rd.
...
Anecdotally, it appears that preferences break out roughly into a third of customers liking 2nd harmonic types, a third liking 3rd harmonic, and the remainder liking neither or both. Customers have also been known to change their mind over a period of time.

Indeed, a little bit of negative 2nd order harmonic distortion, aka "the sugar" makes things sound better. Go listen to a bridged amp, with very low 2nd harmonic distortion and you note how "lean" it sounds. First Watt's SIT1 actually had knob to adjust this. In some of my amps I've thought about specifying such a knob in the front panel.

I think what separates Pass from many is that he knows from experience how to achieve a given sound by design. He purposely "voices" his amplifiers to sound good not to measure good.

I don't think Nelson is a fan of the SIT1 approach:
Nelson Pass said:
I have built many examples of simple 2nd and 3rd harmonic “types” of amplifiers over the last 35 years. When I say “types” I mean that they used simple Class A circuits described as “single-ended” versus “push-pull” and so tended to have a 2nd harmonic versus 3rd harmonic in the character of their distortion, but were not made to deliberately distort.
Nelson Pass said:
Audiophiles have been accused of using 2nd or 3rd harmonic distortion as tone controls to deliberately alter the sound. I suppose that there are people who like it that way, but I don’t think this is generally the case.

The one thing we probably can all agree on is that higher order harmonics, even or odd, are to be avoided. And most importantly, distortion should be minimised (be it in the UK, in the US or elsewhere ;)).
Nelson Pass said:
Nevertheless, whether you prefer 2nd or 3rd order type amplifiers, let’s agree that we wish to minimize the total amount of distortion. And assuming that we have to put up with some distortion let’s also agree that we prefer 2nd and 3rd harmonic components over 4th, 5th, 6th, 7th and so on.
 
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Nelson doesn't want distortion, but he doesn't want to achieve it at the cost of feedback.

The FW F4 is a strange beast. No feedback, quite a bit of components. You have to do all the voltage amplification in the preamp... preferably with transformers. It's an interesting amp.... Right now I'm running it directly from the output of a DAC/headphone amp with a strong analog output state... Nitsch.. At 2VDC it won't swing more than 2V.. so into my 6 ohms speakers it puts out a measly 2/3rds of a watt... as rated. Yet,. in my small office (12x13x19/12 cathedral ceiling with attached 4x8x8 hallway) it fills the room fine. When I use a tube preamp with a healthy 20V output, it runs a healthy the max, ~50 watts and then it plays as loud as you'd want.

With the Fostex, 2/3rds of a watt is all you need... and, naturally, I'm cheating as I run a Parasound Z amp for the little (sub)woofers.

Anyhow, read through Nelson's write up on the F4, specially the owner's manual where he describes topologies.


There's also a lot of information about stuff regeneration, degeneration, etc. for amplifier circuits. at DIYAudio.

My own thoughts tend to go for transformer based voltage amplification followed by a no feedback current amp.

However, then you get the sound of a triode... hmmm....

The SIT1 was indeed an experiment for FW. They used to gauge interest to find out how customers liked it. I have a SIT3 clone and I also had a SIT5 clone. Both got tuned by ear, similar to the FW SIT1. There's a way the ratio between the SIT and the FET in a way that transforms the sound by adding more sugar from one or the other. Distortion changes too.

The SIT5 clone, BTW, was the best amp I've ever had the pleasure of listening... unfortunately mine immolated it's right channel... twice. There's always a price to pay for being on the bleeding edge... So now it got turned into a clone of the FW XA25. Great sounding, but I miss the SIT sound.

I ought to note I also have two DIY Pass Sony VFET amps and one more in the way. Two N channels, one P channel.

If the N channel were available.. a $1000 WiiM Ultra VFET amp, with 10 wpc, would be spectacular. You can imagine though the size of the heatsinks! Just don't tell the ASR review crowd about the rated power specs... ;-)
 
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Why would I be interested in Bluetooth like audio transmission when i have ethernet or WiFi? No loss there.
Airplay is not at all like BT. Airplay (1) is CD lossless quality. Airplay 2 is AAC 256 but can also accept ALAC from Macs as lossless as well. So, not BT at all. A minimum, a step up, at best, excellent. I do not know why people think Airplay was or is like BT. It never was. All I can figure is they have never used Airplay, just read about it. I send streaming Airplay to an Airplay (1) device from a Mac in my office and it is lossless 16/44. I send my own CD ALAC rips from same Mac to WiiM Pro Plus in LR and those are played 16/44 lossless.
But relax, I am very mad Apple does not have (a true) Connect! If WiiM had Apple Music Connect, WiiM and Apple would make a lot more money.
 
Airplay is not at all like BT. Airplay (1) is CD lossless quality. Airplay 2 is AAC 256 but can also accept ALAC from Macs as lossless as well. So, not BT at all. A minimum, a step up, at best, excellent. I do not know why people think Airplay was or is like BT. It never was. All I can figure is they have never used Airplay, just read about it. I send streaming Airplay to an Airplay (1) device from a Mac in my office and it is lossless 16/44. I send my own CD ALAC rips from same Mac to WiiM Pro Plus in LR and those are played 16/44 lossless.
But relax, I am very mad Apple does not have (a true) Connect! If WiiM had Apple Music Connect, WiiM and Apple would make a lot more money.
I fear a 'lot' for WiiM isn't a 'lot' for Apple. But yes, you are right, thinking of Airplay as simple BT is BS.
 
I cannot remember having stated the opposite.


You're ignoring the fact that in digital network devices with DSP software determines the sound quality at least as much as hardware. It might be very convenient to ask for "better output stages", hand picked (or rather ear picked) opamps, "linear power supplies" (because linear is always better than non-linear) and "less noise" without specifying what that means apart from "better sounding". But that's simply not how development works. Consequentially, the term developer is totally appropriate in my book.

I do firmware for a living... have programmed a couple of DSPs in my time. Yes, the filters selected and such makes a big difference.

The correlation between measurements and listening impression can certainly be more complex than some may think. Dealing with it can in part be individual experience or grey knowledge. But as soon as we want make use of listening impressions in more than an anecdotal way we're back in measuring territory. There are well known psychometric methods that can take the uncertainty out of human perception. But this only works in controlled environments.

Agreed. Measurements and observation must be correlated and listening experiences need to be controlled. Otherwise we can't achieve repeatability.

Even if we don't know "WHY" our psychoacoustic behavior works in some ways, we should at least be able to measure the electronic status related to a given listening interpretation.

In this way we learn and push the science of psychoacoustics forward.

This online "consensus" not only can but must be ignored by PD, it's input for marketing, at best. Can you name at least one controlled blind ABX test supporting your theory of the WiiM Ultra sounding inferior?

I don't think we need blind testing, just a controlled listening environment.

I can give you my own experience. The soundstage of a given recording changes, and not for the better, when I use the WiiM own DAC and linear output section vs using an USB DAC. The soundstage is not as deep. For this I used a carefully set up system in my office, listening in the near field with some recordings. The soundtrack of Amadeus is perfect for this... listen to the concertos.

The distance from the front instrument to the back, the pinpoint lateral location of the instruments, all sound more accurate and obvious with the external DACs. Or rather, with the same recording source, changing only the DAC and analog output, the soundstage changes and the voices in a choir sound more separate, never harsh. The WiiM has the shallowest soundstage.

It is repeatable.
  • Used Tidal HiFi Connect over WiFi -AP is in the same room
  • Amadeus soundtrack ( voices, choral, massed strings, orchestra with soloists up front, piano with orchestra, a soundstage stress test).
  • The DACs I used for these listening sessions are Burson Swing with Burson Vivid v7, Topping D90LE and Nitsch Pietus Maximus with Schit Multibit DAC and Unison USB. (*)
  • DIY F4 and FW F6 amps.
  • Acoustic Energy AE1 speakers.
Mind you for this I used the Blue Book version... there are better higher def versions but if I'm gonna listen to one thing over and over and over... well... I better really like the piece. I just wanted to hear the differences.

Now, I posit the issue here is not the DAC per se but the output section... I can, and do, roll amps in the Burson Swing... it makes a difference too!

I guess next, what I ought to do is use the Lycan op amp tester between the amp and the WiiM's own DAC analog output and see what happens. It has a high impedance and will not draw much current from the WiiM but put in a much more "powerful" buffer to the amp. In essence buffering the WiiM from the amp.


I suspect that the sound will change too. And for kicks, I got something like 15, or more, different kinds of opamps.

I went through this with the phono preamp... eventually I settled with the Burson Vivid V7 in there too... but I need to go back. If you want audiophilia nervosa sit down for a weekend to compare the sound of your phono preamp with a bunch of different op amps... take notes... the difference is obvious between some types.. for others, like the ENTIRE Burson opamp history, the changes between generations is more subtle...

My point being that I can hear the differences. So a manufacturer can, and should, run measurements to figure out why. That's the "science" part, the rest is engineering and marketing.

(*) I used their own power supplies... some linear, some switching... I didn't want to open yet another can of worms here. I did use upgraded op amps in the Burson, but they're Burson too, so I figured that was fair and I only have one life to live...
 
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Agreed. Measurements and observation must be correlated. Otherwise we can't achieve repeatability.

Even if we don't know "WHY" our psychoacoustic behavior works in some ways, we should at least be able to measure the electronic status related to a given listening interpretation.

In this way we learn and push the science of psychoacoustics forward.



I can give you my own experience. The soundstate of a given recording changes, and not for the better, when I use the WiiM own DAC and linear output section vs using an USB DAC. The soundstage is not as deep. For this I used a carefully set up system in my office, listening in the near field with some recordings. The soundtrack of Amadeus is perfect for this... listen to the concertos.

The distance from the front instrument to the back, the pinpoint lateral location of the instruments, all sound more accurate and obvious with the external DACs.

It is repeatable.
  • Used Tidal HiFi Connect over WiFi -AP is in the same room
  • Amadeus soundtrack
  • The DACs I used for these listening sessions are Burson Swing with Burson Vivid v7, Topping D90LE and Nitsch Pietus Maximus with Schit Multibit DAC and Unison USB.
  • DIY F4 and FW F6 amps.
  • Acoustic Energy AE1 speakers.
Mind you for this I used the Blue Book version... there are better higher def versions but if I'm gonna listen to one thing over and over and over... well... I better really like the piece. I just wanted to hear the differences.

Now, I posit the issue here is not the DAC per se but the output section... I can, and do, roll amps in the Burson Swing... it makes a difference too!

I guess next, what I ought to do is use the Lycan op amp tester between the amp and the WiiM's own DAC analog output and see what happens. It has a high impedance and will not draw much current from the WiiM but put in a much more "powerful" buffer to the amp. In essence buffering the WiiM from the amp.


I suspect that the sound will change too. And for kicks, I got something like 15, or more, different kinds of opamps.

I went through this with the phono preamp... eventually I settled with the Burson Vivid V7 in there too... but I need to go back. If you want audiophilia neurosis, sit down for a weekend to compare the sound of your phono preamp with a bunch of different op amps... take notes... the different is obvious between some types.. for others, like the ENTIRE Burson opamp history, the changes between generations is more subtle...

My point being that I can hear the differences. So a manufacturer can, and should, run measurements to figure out why. That's the "science" part, the rest is engineering and marketing.
It might be interesting if you have two Wiim consoles, one modded and one unmodded... otherwise, it will become really difficult to be even remotely credible with limited resources.
that s a mimium no?
;-)
I have mods 5534 to 1611 for fun...and would be hard-pressed to talk about them without any means of comparison...except to say that I haven't had any technical problems.(It's just that, as it stands, it's inferior to a good integrated CD player... compared to the Toslink connection on the Wiim "Plus".)
(But when a friend has a "normal" one... I'll give them mine for comparison, finding some flimsy excuse, but not just a "modified" one... it'll be funny.)
;-)
 
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It might be interesting if you have two Wiim consoles, one modded and one unmodded... otherwise, it will become really difficult to be even remotely credible with limited resources.
that s a mimium no?
;-)
I have mods 5532 to 1611 for fun...and would be hard-pressed to talk about them without any means of comparison...except to say that I haven't had any technical problems.
(But when a friend has a "normal" one... I'll give them mine for comparison, finding some flimsy excuse, but not just a "modified" one... it'll be funny.)
;-)

WOW.... I hadn't thought about that.

HOW ABOUT.... socketed op amps in the WiiM Ultra 2? I know it's possible to do.... modify the circuit to use op amps and then put sockets in lieu of the SMD equivalents.

That could also go into the WiiM Ultra Amp 2.
 
1611 is cms

"bi for bi"

Perhaps, like many recent Chinese productions " in the style of ASR".. this 1611-12 will be found in future Wiim productions.
(But the 553* remains the legend...still there...since...1979...)
 
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I do firmware for a living... have programmed a couple of DSPs in my time. Yes, the filters selected and such makes a big difference.



Agreed. Measurements and observation must be correlated and listening experiences need to be controlled. Otherwise we can't achieve repeatability.

Even if we don't know "WHY" our psychoacoustic behavior works in some ways, we should at least be able to measure the electronic status related to a given listening interpretation.

In this way we learn and push the science of psychoacoustics forward.



I don't think we need blind testing, just a controlled listening environment.

I can give you my own experience. The soundstage of a given recording changes, and not for the better, when I use the WiiM own DAC and linear output section vs using an USB DAC. The soundstage is not as deep. For this I used a carefully set up system in my office, listening in the near field with some recordings. The soundtrack of Amadeus is perfect for this... listen to the concertos.

The distance from the front instrument to the back, the pinpoint lateral location of the instruments, all sound more accurate and obvious with the external DACs. Or rather, with the same recording source, changing only the DAC and analog output, the soundstage changes and the voices in a choir sound more separate, never harsh. The WiiM has the shallowest soundstage.

It is repeatable.
  • Used Tidal HiFi Connect over WiFi -AP is in the same room
  • Amadeus soundtrack ( voices, choral, massed strings, orchestra with soloists up front, piano with orchestra, a soundstage stress test).
  • The DACs I used for these listening sessions are Burson Swing with Burson Vivid v7, Topping D90LE and Nitsch Pietus Maximus with Schit Multibit DAC and Unison USB. (*)
  • DIY F4 and FW F6 amps.
  • Acoustic Energy AE1 speakers.
Mind you for this I used the Blue Book version... there are better higher def versions but if I'm gonna listen to one thing over and over and over... well... I better really like the piece. I just wanted to hear the differences.

Now, I posit the issue here is not the DAC per se but the output section... I can, and do, roll amps in the Burson Swing... it makes a difference too!

I guess next, what I ought to do is use the Lycan op amp tester between the amp and the WiiM's own DAC analog output and see what happens. It has a high impedance and will not draw much current from the WiiM but put in a much more "powerful" buffer to the amp. In essence buffering the WiiM from the amp.


I suspect that the sound will change too. And for kicks, I got something like 15, or more, different kinds of opamps.

I went through this with the phono preamp... eventually I settled with the Burson Vivid V7 in there too... but I need to go back. If you want audiophilia nervosa sit down for a weekend to compare the sound of your phono preamp with a bunch of different op amps... take notes... the difference is obvious between some types.. for others, like the ENTIRE Burson opamp history, the changes between generations is more subtle...

My point being that I can hear the differences. So a manufacturer can, and should, run measurements to figure out why. That's the "science" part, the rest is engineering and marketing.

(*) I used their own power supplies... some linear, some switching... I didn't want to open yet another can of worms here. I did use upgraded op amps in the Burson, but they're Burson too, so I figured that was fair and I only have one life to live...
If you can capture the analog outputs of the Ultra and the external DAC you can compare them with DeltaWave software.
 
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