Listening Comparison Test: DSP Phono vs SUT

[watchnerd]

Yes, just select the track in its entirety. Under analyze click Contrast. It will give you the RMS level. Plus it has another box where you can select a different track if you have more than one open in Audacity. And it gives you RMS level of that and the difference in db between them. I'd suggest this will work better than normalize because pops or ticks on an LP can be high enough to corrupt normalizing. I also suggest going in and manually reducing any large ticks or pops like especially the one you get when you sit the need down in the groove.

View attachment 30679

If Audacity is accurate, these two uploads should be adjusted to be within 0.01 dB RMS of each other (used Amplify, rather than Normalize)

These are two different configurations. I'll stay silent for now about what the differences are. No pop or tick removal.

Mystery Config 1:

https://drive.google.com/open?id=1Usu6psmFBVlZ48JRV5RC7W4YRL9cvPfd

Mystery Config 2:

https://drive.google.com/open?id=1kZ2IUR-nqETsU6ZBXvq0GdhNaTtWiRMg

 

[RayDunzl]

Right channel is clipping in both files.

 

[watchnerd]

Right channel is clipping in both files.

View attachment 30703

Yes, I know.

I was surprised when I was watching the meters, but I didn't want to adjust for it for reasons of consistency to prior rips / set ups.

 

[RayDunzl]

I don't hear a difference on the desktop speakers.

I thought I did, then I think I don't.

Good level match.

 

[watchnerd]

I don't hear a difference on the desktop speakers.

Good level match.

There is a circuit difference between them.

I'm curious if the null testing software can identify anything.

 

[watchnerd]

I thought I did, then I think I don't.

Hint: the circuit difference was enough to drop the output of one of the configs by -2.4 dB (before level matching).

 

[Blumlein 88]

There is a circuit difference between them.

I'm curious if the null testing software can identify anything.

I'll give it a try, but the timing variations get in the way. I'll also of course listen a bit later, and do that before trying the Deltawave software.

 

[Blumlein 88]

Okay, they are identifiable as different. It doesn't amount to much. An easy place to hear it is isolated 1:21.5 to 1:28.5 and listen to each. Listen carefully to the piano notes trilled heavily in the right channel and a slightly delayed echo from those in the left. The right channel sounds a little bit less sharp in the version 2 and the echoed delay is less in evidence. Possibly a minor upper midrange FR difference? Maybe a difference in distortion levels? It isn't much, and I don't know you'd hear it just normally listening to a track. I was trying my intent listening method with less than 10 seconds and immediate switching between them.

There are other places to hear the difference like when the cymbals on the drum set are off to one side, but the piano is easier to hear.

This was listening over headphones (Sony MDR 7510 with headphone out of the Antelope Audio Zen Tour). Haven't tried speakers yet.

 

[watchnerd]

Okay, they are identifiable as different. It doesn't amount to much. An easy place to hear it is isolated 1:21.5 to 1:28.5 and listen to each. Listen carefully to the piano notes trilled heavily in the right channel and a slightly delayed echo from those in the left. The right channel sounds a little bit less sharp in the version 2 and the echoed delay is less in evidence. Possibly a minor upper midrange FR difference? Maybe a difference in distortion levels? It isn't much, and I don't know you'd hear it just normally listening to a track. I was trying my intent listening method with less than 10 seconds and immediate switching between them.

There are other places to hear the difference like when the cymbals on the drum set are off to one side, but the piano is easier to hear.

This was listening over headphones (Sony MDR 7510 with headphone out of the Antelope Audio Zen Tour). Haven't tried speakers yet.

Very good.

Do want to know what the difference is?

 

[Blumlein 88]

Very good.

Do want to know what the difference is?

No I don't. And I didn't do this blind. So it might not even be real.

 

[Blumlein 88]

Listening over speakers in short segments, it sounds like version 2 has just a tiny bit more noise in the noise floor between notes. Of course if you had to use different gain that would explain that and might not mean much otherwise. Again, sighted listening impressions. Be nice if some others would listen and chime in. Also this is a tiny not really important difference (which also might not be real).

 

[watchnerd]

Here are 3 more files.

Unlike Mystery 1 and Mystery 2, which were recorded with speakers off, these were recorded with speakers on.

One of these new files also has the same configuration as either Mystery 1 or Mystery 2, but with speakers on.

The rest are all different configurations of SUT and/or no SUT.

The differences here are bigger than in the first two mystery files, so should be easier to tell apart, although volume is leveled to within 0.15 dB.

Mystery Config 3:

https://drive.google.com/open?id=1hjnGoGaAVKZsREPgy5B3nWabvsmjmEZc

Mystery Config 4:

https://drive.google.com/open?id=1espdAAjdt-bILiwuonPux8Ufi4jwWT_l

https://drive.google.com/open?id=1WSMhG3Ff0Wko0GPGyrfxlUlROba9S8vl

Mystery Config 5:

https://drive.google.com/open?id=1w7D2Jtp0Xweag0tLpNpqV0Hg_NOfzRSj

https://drive.google.com/open?id=1Ix1ilzhRHs21GT0mewLzJLryezliwXDd

 

[Blumlein 88]

@watchnerd Not sure what is going on. Sounds like a microphone is on and adding in sounds from the room into them. I hear a girl's voice in two of them (4 and 5 very clearly in 5). Breaths drawn in and other noises that sound like they were in the room and not part of the recording. Did a laptop mix in its microphone with the recording or something of that sort? Maybe it was a TV playing nearby. Anyway, take a listen to these. Check out around the 2 minute mark of 4. Lick the plates of lots of babies????? Black is a winter color. So on and so forth. Mostly in 4 and 5.

 

[watchnerd]

@watchnerd Not sure what is going on. Sounds like a microphone is on and adding in sounds from the room into them. I hear a girl's voice in two of them (4 and 5 very clearly in 5). Breaths drawn in and other noises that sound like they were in the room and not part of the recording. Did a laptop mix in its microphone with the recording or something of that sort? Maybe it was a TV playing nearby. Anyway, take a listen to these. Check out around the 2 minute mark of 4. Lick the plates of lots of babies????? Black is a winter color. So on and so forth. Mostly in 4 and 5.

I'm not 100% sure what happened, and while I could make an educated guess, it might taint things.

I've updated 4 & 5. Links corrected above.

 

[watchnerd]

@watchnerd Not sure what is going on. Sounds like a microphone is on and adding in sounds from the room into them. I hear a girl's voice in two of them (4 and 5 very clearly in 5). Breaths drawn in and other noises that sound like they were in the room and not part of the recording. Did a laptop mix in its microphone with the recording or something of that sort? Maybe it was a TV playing nearby. Anyway, take a listen to these. Check out around the 2 minute mark of 4. Lick the plates of lots of babies????? Black is a winter color. So on and so forth. Mostly in 4 and 5.

Okay, 3 has issues, too. I'll re-do that one another night.

 

[watchnerd]

Okay, I ran some experiments tonight. Sorry no rips.

But the issue I'm hearing has something to do with the subwoofer.

Direct into the Devialet, no SUT, the subwoofer sounds well-blended.

Add the SUT, bass sounds anywhere between lush and lumpy.

Turn off the subwoofer, run the speakers full range (no more high pass), and the SUT sounds much closer to the direct input, with no bass issues. There are still differences....noise floor is lower (yay), dynamics seem a tad improved (yay), there is less air / it's less dry and it's more midrange forward (subtle, mostly a matter of taste preference).

So here are some hypotheses. None of these have been tested yet:

1. The SUT just sends more bass, period, than the direct connection (but why? is it subsonic? but my subsonic filter is on...). So it might simply be a matter of dialing the subwoofer back.

2. There is some acoustic interference issue with the cart/arm/SUT itself that the SUT is magnifying in some way, regardless of subwoofer level.

3. Phase or timing issues being introduced that I don't have an obvious way to assess easily.

 

[Soniclife]

Okay, I ran some experiments tonight. Sorry no rips.

But the issue I'm hearing has something to do with the subwoofer.

Direct into the Devialet, no SUT, the subwoofer sounds well-blended.

Add the SUT, bass sounds anywhere between lush and lumpy.

Turn off the subwoofer, run the speakers full range (no more high pass), and the SUT sounds much closer to the direct input, with no bass issues. There are still differences....noise floor is lower (yay), dynamics seem a tad improved (yay), there is less air / it's less dry and it's more midrange forward (subtle, mostly a matter of taste preference).

So here are some hypotheses. None of these have been tested yet:

1. The SUT just sends more bass, period, than the direct connection (but why? is it subsonic? but my subsonic filter is on...). So it might simply be a matter of dialing the subwoofer back.

2. There is some acoustic interference issue with the cart/arm/SUT itself that the SUT is magnifying in some way, regardless of subwoofer level.

3. Phase or timing issues being introduced that I don't have an obvious way to assess easily.

2 & 3 seem more likely, I was thinking phase all the way through your post.

 

[Blumlein 88]

Low tech test. Put a cup 2/3rd full of water on the SUT case. Play music. See if ripples are in the cup.

High tech version. Smart phones have accelerometers in them. Download a free app to graph the results and sit the phone on the SUT case and see what it picks up, and at what frequencies. Sub on/sub off. They work 3 axis and are very sensitive.

Maybe if you have some long cables move the SUT to a different place. You may have it where some room modes in the low end are strong. Move it a few feet and see if it sounds different.

Also with the sound turned up to at least normal, tap on the case to the SUT with a finger. See if it comes through the speakers.

 

[watchnerd]

Okay, listening again tonight, I now have a nutso question:

If we assume that there is an electro-acoustic feedback loop, whereby the speakers play music that tweaks resonances in the arm and cart, with a miniscule difference in time.......that the act of the signal going through miles of wire in the transformers makes that time difference longer, thereby changing the resonant behavior of the system?

Speed of light would make me think not, but....phase?

 

[restorer-john]

that my 2i2 now works 24/96 in full duplex

My 2i2 reports full duplex up to 24/192K.

It's the version 2.