Teach me Something about specs/numbers

I’m able to AB two DACs with the push of a button. I have a suspicion that the difference I hear is due to a slight Gain or for lack of a better term, “difference in loudness” between the two. I’m not very well versed with differences in loudness beyond Gain, and I can’t find any specs on Gain. Not even sure if that is typically noted besides on preamps, again these are two DACs. Can someone tell me if these specs, below, impact the perceived loud/quiet of a device and if so which one should present a louder signal? If none of these below and Gain is not available, what other specs could impact the slight difference in loudness?

I don’t want to tell you which one I think is louder until I know about which one based on specs should…or if there shouldn’t be a difference based on this info.

Thanks

EDIT: I should note that I’m using balanced, XLR connections…because I kinda think the answer lies in the Vrms stuff…but that is just because I noticed it is on the Analog end of things.

#1

Analog Output 	
	    RCA at 2.2Vrms, 625 Ω 
 	    XLR at 4.4Vrms, 1250 Ω 
Power Consumption 	≤20W 
Frequency Response 	20-40KHz -0.2dB 
THD+N 	0.0010% 
S/N Ratio 	127dB 
Dynamic Range 	>132dB 
Stereo Crosstalk 	-110dB

#2

Analog Output
	RCA at 2.0Vrms, 625 Ω 
 	XLR at 4.0Vrms, 1250 Ω
Power Consumption 	≤20W 
Frequency Response 	20-70KHz -3dB 
THD+N 	0.0020% 
S/N Ratio 	120dB 
Dynamic Range 	>121dB 
Stereo Crosstalk 	-110dB
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DAC #1has an analog output that is 10% greater than DAC #2.
That should result in an increase in “loudness” or listening volume with everything else being equal.

Now whether it would be a linear 10% increase in volume is another thing entirely but it should be an audible difference that could account for the perception that the louder one sounds better.

You will need to use a good level db meter and match listening levels before you can truly compare the pair.

IMHO of course.

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What particular specification tells you that? Is this not the case where bigger is more? ie 4.4 > 4.0 and/or Freq Response -0.2 vs -3 seems more-ish and/or 127 > 120 and/or 132 > 121. All of those to my unknowing mind seem like #1 is bigger, stronger, faster like the six-million dollar man.

There is by no means a 10% difference. The difference is slight but noticeable. Or should I say, I “think” one sounds better and I also am starting to think what I am hearing is a difference in loudness, not necessarily better.

That said It is DAC #1 that I like better. So perhaps (maybe) it is “better” because I like it more and it, on paper, should actually be quieter???

Please shed a bit more light if possible.

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Sorry… dyslexia strikes again…lol.
I edited the reply, I had 1&2 transposed!

So yes #1 is, on paper, the bigger, badder, stronger type😇.
And I base the listening volume difference in this case solely on that analog output difference.
S/n ratio is better too but we are already in superb measurements areas on both units.
And yes I would not have thought 10% louder but audible as you agree.

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Is it only the Analog 4.4 > 4.0? Do the other differences mean much in the realm of human hearing?

Pretty big jump in price between the two and TONS of good press on #1. Should be noted that #2 is by no means inexpensive. Yes I know price does not equal better. That is the reason I’m starting to think #2 actually might send #1 packing.

After lots of reading and persuading by the “DACs don’t matter as much as other things like speakers” crowd I’m starting to think I have more than hit the wall of diminishing returns. I’ve always worried my obsession with gear overpowers the enjoyment of music or at least puts its thumb on the scale…but I’m trying to change that.

I’d like to hear what others think about how the differences on paper between 1 and 2 might/should/shouldn’t translate to next level, game changer, jaw dropping, wife noticed, etc. Then maybe I’ll weigh in on the two configurations.

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Not very likely but let’s see/hear other members thoughts on it.
I see both sets of measurements as being excellent.

I’m now intrigued as to the actual models involved… perhaps you could share that information when it seems discussion is over so nobody can be biased😁

Exactly my plans. Or it devolves into my system is not resolving enough to hear it, or I’m too old, or I don’t have the right power cord. I’m trying the best I can to be honest and analytical. I know we all come with a plethora of bias. I’m also at the point in my life where I can spend what I want…but who wants to spend needlessly no matter if it is X dollars or XXXXXXX dollars (pounds, euro, clams, chickens, etc.)

I was so excited when your had you dyslexic moment. Because that would have meant the one that cost a much as a decent used car was actually “better” being that it should have been quieter not louder :rofl: I got all excited that I had spent wisely and have good enough ears to discern the difference.

Will be curious to see of @Graeme_Finlayson weighs in. I appreciate his thoroughness in explanations.

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The only audible spec [/EDIT] difference [EDIT/] in your listing is output voltage.
#1 has an output voltage, being a factor of 1.1 higher than #2, which equals a level difference of ~0.83dB.
1 dB difference is said to be barely audible, so there you have it, your ears are quite resolving.

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I guess you mean the only spec difference that is audible?

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That’s right…
:upside_down_face:
let me edit…

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Thanks. I thought so. I agree with that. Both SNR and dynamic range are more than enough. The THDs expressed in dB are -100 dB and -94dB, which are most probably indistinguishable, and while the frequency responses can’t be compared as specified, it’s safe to assume attenuation within the audible range is negligible in both cases.

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A much more exact method would be to use just a cheapish multimeter and measure the amplifier AC voltage with a 1kHz sinewave while matching to 1 millivolt at around 75dB or just bearable listening volume.

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Can you explain a bit more on how to do that? I have a multimeter from my tube biasing days. I know enough to be dangerous but can follow directions…or maybe a link to a site? I’ve always used my SPL meter to get them as close as possible.

If you’ve got a ripped test disc’s 1kHz sinewave, use that.
If not, but are subscribing to Qobuz, there’s the following test disc available:


If only on Tidal, you’re on your own…

Now play that 1 kHz tone on repeat and adjust the volume to just be bearable, or use your SPL meter and adjust for around 75dB, but be careful and don’t damage your ears or speakers - I use earplugs whenever doing measurements, since all constant test tones, sinuses or noise, are bothersome to me.

Whip out your multimeter, set it to AC voltage and measure across one amp channels’ binding posts, take note of the reading which ideally should resolve to the millivolt.
Then, with the other DAC set the volume to get the same reading again, et voilà, levels matched…

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You can also use Audacity to generate any tone you wish and save it in a wav file that you can then import in you local Roon library.

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There you go, tons of options…

Is this a valid summary to this point?

  • Both have pretty good specs on paper
  • #1 has a tiny bit more output and if either should sound louder, it should
  • None of the differences besides Vrms is likely to have an impact on human hearing
  • It would be expected that if I can get them level matched very closely the slight “improvement” I’m hearing on the louder one will most likely go away

Thanks for all the help so far. I don’t think if I were to leave the room with one of them playing and somebody switched it I cold tell upon reentry.

I’ll be curious to see what others think when I describe my tests to date.

Would that be red lead on multimeter to positive binding post and black on MM to negative binding post? That kind of stuff always give me a slight pause.

It doesn’t matter, as it’s just AC for the multimeter. The colors are there to make sure both (or all I should say) speakers are connected in phase.

Apologies for my tardiness in replying. Heavy work day today and due to interviewing tomorrow, I’m having to hand over responsibility for my usual Wednesday morning meeting to someone else…

Looking at the numbers for the two devices above, the first posts about 100dB SINAD; the second, 94dB SINAD. Unless you’re listening at concert level volumes, it’s highly unlikely you’ll detect any difference. Linearity for both is pretty good, and I suspect the -3dB for the second device vs the -0.2dB for the first device is largely due to the fact that the measurement range for the second is out to 70kHz. +/- 3dB variation in frequency response is inaudible anyway.

The biggest difference is in output voltage - 4.4 Vrms output vs 4.0 Vrms is a gain of 0.83 dB which is very much audible.

For inaudible differences when level matching, we want +/- 0.1dB, so the main reason you think you prefer #1 is simply by virtue of the fact that it’s that little bit louder than #2.

This is why it’s so important that comparitove listening tests are level matched. A DAC that plays a little bit louder will sound subjectively better.

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