Bitperfect vs 99% volume?

[Lanzar]

Hi!

I'm using the Wiim mini connected with toslink to an external DAC. The sound (spotify, tidal) sounds brighter and harsh compared to a CD-player connected to the same DAC. The volume is also higher than the CD-player when using fixed volume. Setting the volume limiter in the wiim app to 99% semms to soften the sound but also makes it less detailed. So i'm a little bit confused here, is the bitperfect sound at 100% clipping due to the higher output level than my CD and therefore making the sound harsh, or is the volume limiter degrading the sound that much when it's not bitperfect anymore? There is a very noticeable difference switching between 99-100% volume limiter so something is definately going on. I can't figure out the better choice is here, 99% sounds more like the CD-player but then again 100% is bitperfect and therefore "how it is supposed to sound", but after all does not sound right to my ears.

 

[Wiimer]

Hi,
I don't have an exact answer to your question, but someone might have a good answer if you write the model name of the CD player and DAC.

 

[steadyshot]

Good question if you can regulate the fixed digital output volume/power without employing digital volume. I don't know if a firmware update can do that. I would prefer it to be at 95% level

 

[ratty]

You can use the volume limit feature, along with fixed volume. However any adjustment at all will mean the samples are by definition not bit-perfect.

It could be that the DAC is not dealing with inter-sample overs cleanly, and with so much content forced up to full scale in the "loudness wars" there's a potential risk of clipping.

 

[Lanzar]

It’s an old Dacmagic2 so maybe it’s just as you say it can’t deal with intersample overs when volume is set to 100%. The difference in sound is so drastic between 99 and 100% so i find it hard to belive that the wiim:s volume control could degrade it that much. So even though finally achieving that bitperfect sound, i guess i have to trust my ears this time. The sound at 100% isn’t actually bad though, very detailed and bright, but at the same time kinda harsh and very fatiguing compared to the softer and warmer sound at 99% and below.

 

[Lanzar]

And yes i am using the fixed volume at 100%, and just toggling the volume limiter between 99% and 100%

 

[onlyoneme]

Hi!

I'm using the Wiim mini connected with toslink to an external DAC. The sound (spotify, tidal) sounds brighter and harsh compared to a CD-player connected to the same DAC. The volume is also higher than the CD-player when using fixed volume. Setting the volume limiter in the wiim app to 99% semms to soften the sound but also makes it less detailed. So i'm a little bit confused here, is the bitperfect sound at 100% clipping due to the higher output level than my CD and therefore making the sound harsh, or is the volume limiter degrading the sound that much when it's not bitperfect anymore? There is a very noticeable difference switching between 99-100% volume limiter so something is definately going on. I can't figure out the better choice is here, 99% sounds more like the CD-player but then again 100% is bitperfect and therefore "how it is supposed to sound", but after all does not sound right to my ears.

Maintaining bit-perfectness by the streamer is not always the best choice, but it all depends on details, for example DAC's headroom management. 1% difference in the volume limiter equals to 0.6 dB difference of the digital level, which can be noticeable.
Perceived differences of volume levels for different digital sources usually means that at least one of these audio paths does not maintain the digital stream unaltered, ie. is not bit-perfect.

 

[Iannis]

I have noticed a similar problem. When I cast from Spotify (Windows computer or Android tablet) to my Wiim mini with optical output connected to an Amazon Echo Studio, and fixed volume chosen, the sound frequently (not always) is crackly - sounds as if it saturates at the peaks. When I play music from my local NAS via Wiim's DLNA/UPnP, this does not happen. Upon lowering the volume of the optical output to something like 95% via Wiim, the Spotify crackling disappears. I cannot hear any discernible difference in quality, but this may be due to the fact that I only use the free version of Spotify (which is probably MP3 compressed to 128Kbps). Still, the phenomenon is interesting: how can there be "overdriving" to saturation points on a digital signal? All I can think of is that at fixed volume probably some significant jitter is introduced at the optical input of the speaker, which is translated to crackles when converted to analogue.
By the way, a 1% difference in digital volume should be equal to 0.04dB, not 0.6dB. A 5% difference is 0.2dB, both of them very small to significantly affect the 16bit resolution of standard CD quality.

​

 

[Brantome]

I have noticed a similar problem. When I cast from Spotify (Windows computer or Android tablet) to my Wiim mini with optical output connected to an Amazon Echo Studio, and fixed volume chosen, the sound frequently (not always) is crackly - sounds as if it saturates at the peaks. When I play music from my local NAS via Wiim's DLNA/UPnP, this does not happen. Upon lowering the volume of the optical output to something like 95% via Wiim, the Spotify crackling disappears. I cannot hear any discernible difference in quality, but this may be due to the fact that I only use the free version of Spotify (which is probably MP3 compressed to 128Kbps). Still, the phenomenon is interesting: how can there be "overdriving" to saturation points on a digital signal? All I can think of is that at fixed volume probably some significant jitter is introduced at the optical input of the speaker, which is translated to crackles when converted to analogue.
By the way, a 1% difference in digital volume should be equal to 0.04dB, not 0.6dB. A 5% difference is 0.2dB, both of them very small to significantly affect the 16bit resolution of standard CD quality.

​

Maybe worth raising a ticket thru the feedback section of the WiiM Home app when that crackling occurs.

What spdif output resolution are you using on the WiiM to the Studio? And do you get the same crackling if you cast direct to the Studio, not the WiiM?

 

[onlyoneme]

By the way, a 1% difference in digital volume should be equal to 0.04dB, not 0.6dB.

Why? It was also related to the volume limiter, not the volume level BTW.

 

[ratty]

Still, the phenomenon is interesting: how can there be "overdriving" to saturation points on a digital signal?

​

Intersample peaks.

Full scale - Wikipedia

en.wikipedia.org

 

[Iannis]

Maybe worth raising a ticket thru the feedback section of the WiiM Home app when that crackling occurs.

What spdif output resolution are you using on the WiiM to the Studio? And do you get the same crackling if you cast direct to the Studio, not the WiiM?

The specs of the Echo Studio SPDIF input are for up to 48KHz/24bits and this is what I have set in the Wiim. It is a serious omission by Amazon that the speaker cannot accept a higher frequency SPDIF input and downsample the signal itself, although it does this what playing directly 96/24 streams from Amazon music. The Wiim does the job faultlessly when streaming files up to 192/24 from my NAS. The crackles only occur when casting from Spotify using the DLNA/UpnP Wiim exposes to the LAN. Direct casting to Amazon devices is not supported by Spotify. Previously, I was using a Chromecast Audio device again connected via SPDIF to the Studio but had problems with controlling the downsampling in higher frequency sources. And yes, the crackles did appear as well when casting Spotify to the Chromecast -->SPDIF --> Echo studio. This is what makes me think that it is not the Wiim's end which causes the issue.

 

[MrSoul4470]

Intersample peaks.

Full scale - Wikipedia

en.wikipedia.org

Intersample peaks are a problem in the analog and not digital domain and even there they usually are not a huge issue. I've seen intersample peaks up to almost +3 dB and they did not cause audible issues.

Crackling clearly sounds like it is a digital issue.

 

[onlyoneme]

I would rather say that it's a problem in the digital domain further manifested in the analog domain.
It's easy to make examples when the effect of intersample peaks is obviously audible, so both scenarios can happen.

 

[Brantome]

Direct casting to Amazon devices is not supported by Spotify.

It is indeed supported and has been for a while - see my Spotify devices screen below, which includes echo dots, echo flex, echo show and on the following page an echo plus and echo studio as well as Alexa MRM groups. You have to link your Spotify account in the Alexa app and occasionally ask the device “Alexa, Spotify Connect” if it doesn’t show in the Spotify device list.

Admittedly, this may not work in all regions plus your Alexa account and Spotify account regions need to match, although I recall there may be a workaround for that.

 

[onlyoneme]

It is indeed supported and has been for a while - see my Spotify devices screen below, which includes echo dots, echo flex, echo show and on the following page an echo plus and echo studio as well as Alexa MRM groups. You have to link your Spotify account in the Alexa app and occasionally ask the device “Alexa, Spotify Connect” if it doesn’t show in the Spotify device list.

Admittedly, this may not work in all regions plus your Alexa account and Spotify account regions need to match, although I recall there may be a workaround for that.

View attachment 4039

And I thought that I have a lot of audio devices in my network...

 

[Iannis]

Intersample peaks.

Full scale - Wikipedia

en.wikipedia.org

This is an interesting idea. Assuming that Spotify applies normalisation based on loudness, their algorithm may rely on RMS power measurements: this could create peaks outside the upper limits, which could result in successive (16 bits at value 1) peaks (saturation/clipping) translated by the DAC into crackles. This explains the effect of lowering the volume at the digital stage. Two remarks here:
- when casting to a Chromecast speaker directly (google mini) no crackles appear
- maybe there is a way to setup Spotify to avoid normalisation

It is indeed supported and has been for a while - see my Spotify devices screen below, which includes echo dots, echo flex, echo show and on the following page an echo plus and echo studio as well as Alexa MRM groups. You have to link your Spotify account in the Alexa app and occasionally ask the device “Alexa, Spotify Connect” if it doesn’t show in the Spotify device list.

Admittedly, this may not work in all regions plus your Alexa account and Spotify account regions need to match, although I recall there may be a workaround for that.

View attachment 4039

OK, but I am not sure the linking of a free Spotify account with Alexa can happen; I will check though.

 

[Brantome]

OK, but I am not sure the linking of a free Spotify account with Alexa can happen; I will check though.

I use a free Spotify account

 

[Brantome]

And I thought that I have a lot of audio devices in my network...

It’s a bit of a mess admittedly with additional test MRM groups with echos & wiims, echos & fire tv devices, WiiM Mini and pro/ plus, WiiM pro and plus (for hi res Amazon Music MRM) etc. Yes, I do need to tidy it up and delete the ones I don’t use Tbh, I seldom use multi room groups as I tend only to listen in the room I’m in…

 

[Achim1811]

It is hard for me to confess....you may know my relation to "smart" devices like Echo is not that from a native Alexa user
I have a Studio at my bedside and listen to audio books via Spotify nearly every evening while falling to sleep.
Please do not give this information to @Brantome and @Wiimer