Sound quality when using EQ or Volume Control

[steadyshot]

I assume you are using the volume control of your preamp and integrated amp. In this case it makes sense to have the maximum voltage level from the Wiim DAC output.

The down side is you are giving up bit perfect. Maybe want set you amp to 1.5V sensitivity. Set Wiim at 1V 100% to see which way sounds better.

I like how the 1v mid - 1.5v combination sounds. Of course i use the volume control of my roksan attessa amp. However the sound is more dynamic and details are more effortlessly emerging from 0.8v and high - 0.75vrms sensitivity combination. That is why I like to fine tune the voltage match. A little less voltage will be ideal. I mean it is a 24 bit volume control, reducing it by a little to achieve a perfect match (reduce 0.784vrms to 0.75vrms) is worth it I believe compared to the gains I will get with perfect voltage match. I am disregarding the 2v option since 1v and 0.8v offers close to full voltage sinad while they have the necessary headroom to handle intersample peaks compared to 2v which has 2db headroom for intersample peaks.

 

[KCS]

Interesting. Could you try one more experiment? Set you amp to 0.75V sensitivity and Wiim at 500mV and 100%?

 

[steadyshot]

Interesting. Could you try one more experiment? Set you amp to 0.75V sensitivity and Wiim at 500mV and 100%?

Very nice! Maybe it sounds cleaner but a little less dynamic

 

[KCS]

Yes, that is my impression too. I was trying different settings. Somehow I got it set to 500mV and was surprised. Don't have a good explanation. Maybe setting it to a lower voltage create less stress/noise for Wiim. That's why I asked you to do the experiment even though I am using the coax output, not the internal DAC.

 

[mtg]

Thank you for this most helpful thread. A question: I have a WiiM Mini feeding an SMSL SU-1 via the optical input and from there through a passive amp / switcher to my active speakers. The reason for the passive amp is that that the active speakers' input is rated at 1Vrms, whereas the SU-1 outputs at 2Vrms, and there is real bad clipping without any attenuation.

Now, I am told that DSP volume reduction in the Mini also reduces the SU-1's voltage output (still trying to wrap my head around the idea). However, I find the sound way better if I attenuate it passively. Bass/sub-bass sound way more full, vocals cleaner, harmonics crisper. Does this make any sense or should attenuation via the Mini sound better than with a passive amp?

 

[harkpabst]

Thank you for this most helpful thread. A question: I have a WiiM Mini feeding an SMSL SU-1 via the optical input and from there through a passive amp / switcher to my active speakers. The reason for the passive amp is that that the active speakers' input is rated at 1Vrms, whereas the SU-1 outputs at 2Vrms, and there is real bad clipping without any attenuation.

Now, I am told that DSP volume reduction in the Mini also reduces the SU-1's voltage output (still trying to wrap my head around the idea). However, I find the sound way better if I attenuate it passively. Bass/sub-bass sound way more full, vocals cleaner, harmonics crisper. Does this make any sense or should attenuation via the Mini sound better than with a passive amp?

The SU-1 does not put out 2 Vrms continuously, of course. It all depends on what is in the digital signal fed to it. If that signal reaches 0 dBfs (digital full scale), then the output is 2 Vrms. So, if the digital input signal has already been modified by digital volume control, then the output will be noticeably less.

Digital volume control always means loss of digital precision, increased digital noise. There is some headroom for this approach in 24 bit digital audio and there is some clever trickery in most digital volume control chips to retain as much precision as possible at medium levels.

However, if attenuation on the analog side sound better to you, then just keep it like that. It's not technically worse than digital volume control, at all.

 

[mtg]

Thanks a lot. Most helpful. I will try some combination of both (perhaps limiting max volume up to 90%, as I understand from the thread that should be enough to reduce output from 2Vrms to 1Vrms), and see how it goes.

But as of now, I feel the difference is huge if I adjust the sound via either the Mini or the Ol Switcher alone. To the point that, given how popular the SU-1 is, I feel SMSL should make a passive or preamp version of the DA-1 (or JDS Labs could match the size of the Ol Switcher to the SU-1's -- it's a rather elegant pairing).

 

[Griff]

Thanks a lot. Most helpful. I will try some combination of both (perhaps limiting max volume up to 90%, as I understand from the thread that should be enough to reduce output from 2Vrms to 1Vrms), and see how it goes.

But as of now, I feel the difference is huge if I adjust the sound via either the Mini or the Ol Switcher alone. To the point that, given how popular the SU-1 is, I feel SMSL should make a passive or preamp version of the DA-1 (or JDS Labs could increase the dimensions of the Ol Switcher to match the SU-1 -- it's a rather elegant pairing).

A good passive volume control after the dac stage is fine. I use a ALPS27 one but have used a Fostex studio one as well. I would say as long as you are not getting any channel bleed or noise then you are good.

 

[mtg]

Thank you so much, guys. -10% + fine tunning through the Ol Switcher is awesome here. Some volume normalization by Tidal Connect would go a long way toward making the experience just perfect.

 

[venkyrenga]

I am only reducing the higher frequencies on my wiim pro's GEQ as my system is slightly bright. And I am using coax out and keeping the volume at fixed out as there are no gains to compensate for. Hoping this doesn't affect the sound quality?

 

[harkpabst]

I am only reducing the higher frequencies on my wiim pro's GEQ as my system is slightly bright. And I am using coax out and keeping the volume at fixed out as there are no gains to compensate for. Hoping this doesn't affect the sound quality?

I hope applying the EQ does affect the sound quality in a positive way, otherwise you wouldn't do it.

There's nothing wrong with your setup, as long as you only use negative EQ digital clipping will not occur.

 

[venkyrenga]

I hope applying the EQ does affect the sound quality in a positive way, otherwise you wouldn't do it.

There's nothing wrong with your setup, as long as you only use negative EQ digital clipping will not occur.

I meant if the sound quality will be affected in any negative way for using the GEQ.

 

[Mr Ee]

I meant if the sound quality will be affected in any negative way for using the GEQ.

Seems to me that the only true measure of 'negative' in this context is if you (and only you) think it sounds worse as a result of applying the geq.
The mere fact the signal has been altered (albeit on purpose) would be negative to some, and yet such alterations can make listening to music much more enjoyable overall.
Put another way, you might go out and buy new speakers to tame the brightness, and because it sounds better (to you) that would be a SQ improvement. Playing with the source signal to get a similar improvement really isn't any different, imo.
Whatever lets you enjoy the music more for longer can't be a negative, no matter what any naysayers might say!

 

[mtg]

Seems to me that the only true measure of 'negative' in this context is if you (and only you) think it sounds worse as a result of applying the geq.
The mere fact the signal has been altered (albeit on purpose) would be negative to some, and yet such alterations can make listening to music much more enjoyable overall.
Put another way, you might go out and buy new speakers to tame the brightness, and because it sounds better (to you) that would be a SQ improvement. Playing with the source signal to get a similar improvement really isn't any different, imo.
Whatever lets you enjoy the music more for longer can't be a negative, no matter what any naysayers might say!

Agreed. But also think lots of us, especially newbies like me, do not trust our ears enough or have a large enough baseline for comparison. So we look to know from the more experienced folks here things like whether volume DSP implemented by the WiiM Mini's SoC would be objectively as good as attenuation implemented by a pot like those that Class-D amps generally seem to have (while generally fairing good in measurements by sits like ASR).

It may be that we can't ourselves hear the difference in a short comparison or in a comparison without proper A/B-ing tools. Yet, we may still want to set things in accordance with what would be objectively better, so that, in situations where those differences could be heard, we hear them in the better way.

For what is worth, I can hear it when I abuse the Mini's volume DSP. Passive attenuation sounds way better to me. Setting the Mini's max volume at 90%, however (and though I understand this reduces voltage from 2Vrms to 1), does not seem, to my years, too detrimental to sound quality. For all the rest I rely on the potentiometer. Is that the better approach? No clue.

 

[Mr Ee]

Agreed. But also think lots of us, especially newbies like me, do not trust our ears enough or have a large enough baseline for comparison. So we look to know from the more experienced folks here things like whether volume DSP implemented by the WiiM Mini's SoC would be objectively as good as attenuation implemented by a pot like those that Class-D amps generally seem to have (while generally fairing good in measurements by sits like ASR).

It may be that we can't ourselves hear the difference in a short comparison or in a comparison without proper A/B-ing tools. Yet, we may still want to set things in accordance with what would be objectively better, so that, in situations where those differences could be heard, we hear them in the better way.

For what is worth, I can hear it when I abuse the Mini's volume DSP. Passive attenuation sounds way better to me. Setting the Mini's max volume at 90%, however (and though I understand this reduces voltage from 2Vrms to 1), does not seem, to my years, too detrimental to sound quality. For all the rest I rely on the potentiometer. Is that the better approach? No clue.

True, but you also oftimes come across those espousing their own doctrines to the exclusion of any other.
Such as it's not perfect unless it's bit perfect
I might hold a few of my own hifi beliefs that others would disagree with, but my main two centre around (individuals') enjoyment and convenience.

 

[mtg]

Question: there are reviews on Youtube claiming a difference in sound quality between the WiiM Mini and WiiM Pro even when used purely as streamers, in bit-perfect mode -- that is, in optical output, without any form of DSP. I have some difficulty wrapping my head around that. If there was any tampering with the sound by the Mini, there would be tampering with the encryption as well -- and then the MQA files would not work as MQA files. Their integrity would have been violated and my DAC would not be turning on the blue, studio-quality MQA light (nor the green, or the fucsia, for that matter). That is what happens, for example, when there is DSP by the Mini. The DAC still plays the audio, but as something else. The MQA light does not turn on.

Can there really be any difference in sound quality between the optical outputs of the WiiM Mini and the WiiM Pro when used in bit-perfect mode?

 

[canard]

My Pro tests

I've got my unit, so time for testing. First batch are tests when connected to RME ADI-2. In REW FFT tests there is nothing to say - performance over coax and toslink is the same and equal to Mini. My measurements include sine 0 dBFS, j-test, SMPTE and sweeps, all in 48kHz and 96 kHz.

forum.wiimhome.com

 

[Brantome]

Question: there are reviews on Youtube claiming a difference in sound quality between the WiiM Mini and WiiM Pro even when used purely as streamers, in bit-perfect mode -- that is, in optical output, without any form of DSP. I have some difficulty wrapping my head around that. If there was any tampering with the sound by the Mini, there would be tampering with the encryption as well -- and then the MQA files would not work as MQA files. Their integrity would have been violated and my DAC would not be turning on the blue, studio-quality MQA light (nor the green, or the fucsia, for that matter). That is what happens, for example, when there is DSP by the Mini. The DAC still plays the audio, but as something else. The MQA light does not turn on.

Can there really be any difference in sound quality between the optical outputs of the WiiM Mini and the WiiM Pro when used in bit-perfect mode?

Personally speaking I don’t hear a difference. YouTube reviewers are only expressing their opinion - it doesn’t make it right.

 

[onlyoneme]

Question: there are reviews on Youtube claiming a difference in sound quality between the WiiM Mini and WiiM Pro even when used purely as streamers, in bit-perfect mode -- that is, in optical output, without any form of DSP. I have some difficulty wrapping my head around that. If there was any tampering with the sound by the Mini, there would be tampering with the encryption as well -- and then the MQA files would not work as MQA files. Their integrity would have been violated and my DAC would not be turning on the blue, studio-quality MQA light (nor the green, or the fucsia, for that matter). That is what happens, for example, when there is DSP by the Mini. The DAC still plays the audio, but as something else. The MQA light does not turn on.

Can there really be any difference in sound quality between the optical outputs of the WiiM Mini and the WiiM Pro when used in bit-perfect mode?

Giving a quick answer - another factor which may affect the sound quality is the jitter on the toslink output. And its influence highly depends on the DAC.

 

[Steve Woodhouse]

Giving a quick answer - another factor which may affect the sound quality is the jitter on the toslink output. And its influence highly depends on the DAC.

It is indeed. Fortunately, this is a fixed problem in most decent DACs.