Sound differences between USB-SPDIF Converters?

[Felix]

Hey there,
I want to be able to listen to lossless audio on apple ausic via the wiim amp and for that purpose I think it is best, not to get a DAC since thats already inside the wiim amp, but rather trying to keep the signal digital until its converted inside the wiim amp. So now I am wondering wether there would be any noticable difference in sound when it comes to USB-C to SPDIF converters since they actually keep all the digital information, right? I found a threat regarding this topic where some people recommended this adapter: https://www.amazon.de/Cubilux-TOSLINK-Optisches-Converter-Kompatibel/dp/B09QFYNB7Y It seems to be quite popular but actually I am a little bit confused by how cheap this thing is (25€) and it looks a little bit like plastic-trash. On the other hand there is stuff like the TOPPING D10 for around 100 € with a lot of recommendations online, but - this thing is also it's own DAC. So I am wondering if the price is jsut that high because of the DAC features or is it actually because also the sound of the SPDIF Converter will make a difference? Happy about all opinions, am new to the game.

Best Regards,
Felix

 

[Kampernaut]

So now I am wondering wether there would be any noticable difference in sound when it comes to USB-C to SPDIF converters since they actually keep all the digital information, right?

You will discover that people are divided on this issue. Some will say that it is scientifically impossible for there to be any differences between digital sources because of the error correction performed in the digital domain.

Others will swear they can discern differences in digital audio sources, but seem unable to explain why to the satisfaction of those that accuse them of talking bullshit.

I suggest you listen to a few different converters and form your own opinion. In the end, it is only your personal opinion of sound quality that matters.

On the other hand there is stuff like the TOPPING D10 for around 100 € with a lot of recommendations online, but - this thing is also it's own DAC. So I am wondering if the price is jsut that high because of the DAC features or is it actually because also the sound of the SPDIF Converter will make a difference?

As you suggest, you are not comparing like with like. The purpose of the D10 is indeed to act as a DAC and why it costs more.

Again, you will discover endless debate on the sound quality differences between DACs and the value of using a separate one instead of the one built into the WiiM Amp. IMO, this is down to your personal opinion, and I recommend you start with the WiiM amp alone so that you have a basis for comparison.

If appropriate, you might consider using an Apple TV to stream lossless Apple Music and connect to the WiiM amp via your TV’s HDMI or Optical port. Your TV then becomes a brilliant Apple Music playback control device because of the huge screen. This is what I do. Just to warn you, the Apple TV/TV combo may not give you a bit-perfect input for your lossless audio stream to the WiiM Amp. It may all be resampled to 24-bit/48 kHz. However, I doubt you will be able to tell.

An Apple support article asserts that the AAC codec: ‘delivers audio that’s virtually indistinguishable from the original studio recording’. That means Apple think AirPlay is good enough and lossless is hardly worth pursuing. Why not try for yourself and compare it with lossless over USB → Optical → WiiM Amp? You might find that you can’t spot the difference with stereo equipment at this level.

In my experience, the parametric EQ/room correction features of the WiiM have a dramatically more noticeable effect on stereo audio quality than the minor effects of AAC v Lossless or different DACs. The Apple TV interface gives the most marked improvement to my overall music enjoyment than anything else.

Dolby Atmos tracks (or Spatial Audio as Apple call it) can represent a marked improvement to any stereo reproduction. This seems to be where the music industry is headed, but of course, a whole different class of audio hardware to the WiiM Amp. I wonder what you would think of Spatial Audio through a pair of HomePods?

 

[cc_rider]

I have two of the Cubilux optical to USB converters. They’re solidly made of metal, and work quite well. They are also bit-perfect, so won’t affect the signal at all.

 

[Griff]

Smsl do one, model is PO100 pro https://www.smsl-audio.com/portal/product/detail/id/808.html . It sits between the two you mention,

 

[AlPo]

Smsl do one, model is PO100 pro https://www.smsl-audio.com/portal/product/detail/id/808.html . It sits between the two you mention,

I second this recommendation. PO100 was measured by Vintageflanker @ ASR and showed solid results. I own one for exactly the same purposes: streaming Hi-Res Apple music via my ProPlus into my system

 

[Felix]

Thanks for all your nice replies! I will try to address the points that matter most to me.

You will discover that people are divided on this issue.

Jup, that's what I already found on the internet - but what I am wondering is, if thats only regarding the quality of the DAC itself wich, as far as I got it, will not use at all since Im using the Wiim Amps DAC and just need the digital signal to get there - is that right?

you might consider using an Apple TV to stream lossless Apple Music

I would love to, but by TV setup does not allow be to do so since I am using a portable beamer wich does not have the needed HDMI-ARC connections. I just ordered some kind of splitter though, let's see.

It may all be resampled to 24-bit/48 kHz

That's totally fine to me.

That means Apple think AirPlay is good enough and lossless is hardly worth pursuing.

I also read that and put it to the test because I wanted to find out if all that bla is even worth it. I got a test subscription for Tidal and played some songs that were even just 16bit 44.1khz straight from the Wiim and compared it to my AirPlay Stream back and forth and I am a 100 percent sure that I can tell a huge difference in the spaciousness of the sound and especially the highs and mids. So I was actually hoping not to hear a difference so I could just put this topic to the side but now I want to achieve this audio quality forever I don't want to change from Apple Music though because of a big library and I'm an Apple guy unfortunately haha.

the parametric EQ/room correction features of the WiiM have a dramatically more noticeable effect

Do you use an external mic for that measurement? I found with just the iPhones mic it did not give me a satisfying result.

I wonder what you would think of Spatial Audio through a pair of HomePods?

I sometimes have coming out of my AirPods Pro 2 and to be honest I don't like it at all, it irritates me a little and I think everything sounds far away in a big room but thats of course just my taste. For nor I prefer regular mixes.

They’re solidly made of metal, and work quite well

Good to know, thank you!

I second this recommendation.

And do you think it's worth an upgrade from a 25€ dongle? This thing costs more but it also has HDMI and Coaxial out wich I do not need. So maybe in that case I am just paying for these "translation" features?

There is one overall question I still don't really get: When using a USB - SPDIF Converter, will the DAC-Chip actually be used for that or is that a totally different story?

Best regards and thanks for all your answers,
Felix

 

[Kampernaut]

up, that's what I already found on the internet - but what I am wondering is, if thats only regarding the quality of the DAC itself wich, as far as I got it, will not use at all since Im using the Wiim Amps DAC and just need the digital signal to get there - is that right?

Yes

Do you use an external mic for that measurement? I found with just the iPhones mic it did not give me a satisfying result.

Yes, built-in RC wasn’t very good. I used the HouseCurve app on iPhone and followed the extensive advice in their help pages.

Regarding the converters, order them all from Amazon and only keep the one that is cheapest/best when you listen.

Good luck.

 

[VintageFlanker]

I second this recommendation. PO100 was measured by Vintageflanker @ ASR and showed solid results.

And I still have too units that are often used for measurements purposes. They work great so far, and are 100% transparent (in digital domain) with just about every test I run.

 

[AlPo]

And do you think it's worth an upgrade from a 25€ dongle? This thing costs more but it also has HDMI and Coaxial out wich I do not need. So maybe in that case I am just paying for these "translation" features?

There is one overall question I still don't really get: When using a USB - SPDIF Converter, will the DAC-Chip actually be used for that or is that a totally different story?

Using the SMSL PO100 can give you at least a peace of mind that there is nothing in its measured performance that may reasonably affect the sound reproduces by the DAC in your device downstream (the DAC chip of which of course is used in this scenario). But the suggestion to order a few of these converters from Amazon and test for yourself is also very reasonable.