DAC burn-in/break-in? My Gustard X16 measurements

[Pdxwayne]

Bit of a difference between your c 0.02 dB and OP 0.2dB channel difference (if we assume both ADC comparable). I do wonder if he has a lemon.

But for me, the only test that matters is if he can tell the difference between the E30 and X16 blind and level matched with filters engaged that behave the same (and I would use the ones closest to brickwall). If he can, then I would return the X16 and find something else- possibly another e30!

I checked the 0.2db tone examples yesterday night and it seems I could sense 0.2db down more than 0.2db up. Unfortunately that there is no test just to check for either up or down. Else I should still be able to pass 0.2db down only blind tests.

Before I could start the 0.2db blind tests, it was halted due to complaint from my wife all the way from upstairs! This was after I already ran the 0.5db tests prior with my stereo. So understandable that it was getting VERY annoying for my wife.....

 

[Pdxwayne]

Powered on and tested within one hour.

Thanks! Good for you! I am now really curious if mine would change at all after 3 weeks of warm up.

 

[Jimbob54]

Thanks! Good for you! I am now really curious if mine would change at all after 3 weeks of warm up.

You have cooled it down and shown it changes back to levels when you first got it and measured . You have had it over 3 weeks. What you measure now at room temp with it powered on for an hour or so of use is what it will be forever now, surely?

 

[Pdxwayne]

You have cooled it down and shown it changes back to levels when you first got it and measured . You have had it over 3 weeks. What you measure now at room temp with it powered on for an hour or so of use is what it will be forever now, surely?

Yeah, likely forever....But still curious about longer term warming effects of my x16.

I mentioned that after 3 weeks straight of powered on, it seems I enjoyed the same song a bit more than brand new. So, curious if this is purely "mind", or something more DAC specific that changed.

 

[Pdxwayne]

Yes, typical warm up thing, not audible but measurable.
Far below any audible thresholds.
B.t.w. to get a feel of the actual present output voltages can you run the REW test but connect your multimeter on the balanced out ?

The measurements in my prior tables were all using RCA out. OK to provide RCA meter readings for consistency sake? Thanks!

 

[Jimbob54]

Yeah, likely forever....But still curious about longer term warming effects of my x16.

I mentioned that after 3 weeks straight of powered on, it seems I enjoyed the same song a bit more than brand new. So, curious if this is purely "mind", or something more DAC specific that changed.

The only way to get close to answering that is either level matched, filter matched blind testing your warmed up X16 against a brand new cold one. Or, possibly, blind testing your X16 cold vs the e30 then warmed up vs the e30. If you can reliably tell/ prefer to the E30 to a cold x16, but not to a warm x16, you might have gone a way to proving your point.

Personally, if I was happy with the sound of the x16 now, I would leave things be. Further measurements aren't going to yield anything of use, IMHO.

 

[Pdxwayne]

The only way to get close to answering that is either level matched, filter matched blind testing your warmed up X16 against a brand new cold one. Or, possibly, blind testing your X16 cold vs the e30 then warmed up vs the e30. If you can reliably tell/ prefer to the E30 to a cold x16, but not to a warm x16, you might have gone a way to proving your point.

Personally, if I was happy with the sound of the x16 now, I would leave things be. Further measurements aren't going to yield anything of use, IMHO.

Yes, I am happy with my x16. I especially like how it controls my twin subs via xlr. I don't just listen to music with my Paradigm Persona.

At least when using my low cost headphones, sighted quick RCA switch tests was too close to pass a blind test between E30 and x16. I already tried with cooled down x16 vs e30.

Next is the stereo setup. I can cool down the x16 again and just listen. If I hear no obvious issue that bugs me, I would just call it a day and let it be, without even doing extensive blind tests using E30.

I will do this cooled down, stereo listening, check about 3 weeks from now. I am still very curious about my x16 long term warm up effects.

 

[solderdude]

The measurements in my prior tables were all using RCA out. OK to provide RCA meter readings for consistency sake? Thanks!

You can also measure the AC voltage on one RCA. Set the sweep slow. It is about getting a ballpark figure to see at which levels you are measuring.
As REW is not calibrated (which you would have to do yourself) it is hard to say how high the test voltage is.
Was just curious, won't change the FR plot though.

 

[Pdxwayne]

Yep looks good too. We have a nice thread about audibility thresholds here.

https://www.audiosciencereview.com/...-thresholds-of-amp-and-dac-measurements.5734/

Hmm, here is this mention in the first post of the thread:
".....
Psychoacoustics: Facts and Models by Hugo Fastl and Eberhard Zwicker is not a very quotable book, but on pages 180-181 it makes it clear that a change in SPL of less than 0.2 dB can be heard by humans.
......
"

 

[Jimbob54]

Hmm, here is this mention in the first post of the thread:
".....
Psychoacoustics: Facts and Models by Hugo Fastl and Eberhard Zwicker is not a very quotable book, but on pages 180-181 it makes it clear that a change in SPL of less than 0.2 dB can be heard by humans.
......
"

Not necessarily the same as saying humans can detect an 0.2 dB challenge imbalance with music. Again, the E30 doesnt have the imbalance , so blind testing the 2 DACs , if you can tell them apart, that might be one of the factors enabling you to.

 

[Pdxwayne]

You can also measure the AC voltage on one RCA. Set the sweep slow. It is about getting a ballpark figure to see at which levels you are measuring.
As REW is not calibrated (which you would have to do yourself) it is hard to say how high the test voltage is.
Was just curious, won't change the FR plot though.

As you know, my meter is not accurate. Maybe ok up to 120 Hz. Still want me to check from 20hz to 20khz using my meter when running REW? Or just a limited range of frequencies, like 20 Hz to 120 hz? Continue with same REW dB of -20 (I used this to compare 2hr vs 22hr powered on, and not to over volt the Solo) OK? Thanks!

 

[Pdxwayne]

Not necessarily the same as saying humans can detect an 0.2 dB challenge imbalance with music. Again, the E30 doesnt have the imbalance , so blind testing the 2 DACs , if you can tell them apart, that might be one of the factors enabling you to.

Yes, will see if I can convince my family during spring break to help me do blind tests. One DAC will need to be finely adjust using Topping L30 to match voltage. As is, E30 is louder by ~0.7db based on my various checks. Those 0.5db increment volume change of DAC can't voltage match them.

 

[Jimbob54]

Yes, will see if I can convince my family during spring break to help me do blind tests. One DAC will need to be finely adjust using Topping L30 to match voltage. As is, E30 is louder by ~0.7db based on my various checks. Those 0.5db increment volume change of DAC can't voltage match them.

Let the experts rule but I'm not sure how running only one through the L30 doesn't run the risk of saying any changes are due to the L30, transparent though it may be.

 

[Frio]

Hmm, here is this mention in the first post of the thread:
".....
Psychoacoustics: Facts and Models by Hugo Fastl and Eberhard Zwicker is not a very quotable book, but on pages 180-181 it makes it clear that a change in SPL of less than 0.2 dB can be heard by humans.
......
"

So what is the point, you measure something just to proof what you heard but don't measure the chain you just postulate that it is the x16. Who knows what channel imbalance the concerning amp has or the speakers, those add up too, to the initial hearing expirience, which is also not possible to reproduce. Basically when we look through the last week's it is just about changing goalposts.

 

[Pdxwayne]

Let the experts rule but I'm not sure how running only one through the L30 doesn't run the risk of saying any changes are due to the L30, transparent though it may be.

That was the only way I could do E30 vs KTB blind tests last year using quick RCA switch. KTB is the louder one and can't adjust volume. Thus, I used L30 to up the E30 voltage to match KTB. If I can't do that, then I have no way of doing "quick" switch.

 

[Pdxwayne]

So what is the point, you measure something just to proof what you heard but don't measure the chain you just postulate that it is the x16. Who knows what channel imbalance the concerning amp has or the speakers, those add up too, to the initial hearing expirience, which is also not possible to reproduce. Basically when we look through the last week's it is just about changing goalposts.

The chain for which I believe I heard a difference is Parasound A21 and Paradigm Persona B. DAC direct to amp.

E30 with same setup for 2 weeks. Then, switch DAC once I got the x16. Everything else exactly same. That was when I sensed a difference.

I guess only thing left is blind tests with same chain.

 

[solderdude]

As you know, my meter is not accurate. Maybe ok up to 120 Hz. Still want me to check from 20hz to 20khz using my meter when running REW? Or just a limited range of frequencies, like 20 Hz to 120 hz? Continue with same REW dB of -20 (I used this to compare 2hr vs 22hr powered on, and not to over volt the Solo) OK? Thanks!

set sweep start to 50Hz and stop to 1kHz

 

[Pdxwayne]

set sweep start to 50Hz and stop to 1kHz

Here is the chart. My meter initially not stable, then then after initial second or so, pretty stable at ~0.277V. Whole thing took ~20+ seconds.

 

[Pdxwayne]

What is strange is that the db increased today for Left. Today I used REW stereo out so I can use the DAC's right RCA out for meter measurement. Previously always selected single REW channel output.

I now wonder if there are interactions between channels when DAC receive stereo signals.....

 

[Pdxwayne]

When using REW to measure Left channel and meter to measure Right channel, meter reading eventually stabilized at 0.277V.
When using REW to measure Right channel and meter to measure Left channel, meter reading very uneven, then eventually stabilized a bit longer at 0.283V.

~1.5 days later, the x16 seems to move up by +0.2db as compared to 22 hours powered up db. The difference between channel seems to narrow a little.

These two latest measurements are captured when using REW stereo output. Also, I prolong the sweep time by increasing log length to 1million. All my previous measurements were using REW single channel output and 256 log length.

Later today will go back to measure single channel again using REW single channel output and 256 log length, just to compare.

I also wonder if the Solo has warm up effect. I just plugged it in from ~12 hours of unplugged. So will contine plugged in Solo and check again later, the way I checked just now.