I think this subject can be theorized to death. Won't change the user-that-listens experience though and in the end we are left with just theory.
@Markw4, validate? Nothing more than an elma stepped switch, 6 way, 2 live, 4 dead inputs. Switcher would flick multiple times to hide what they actually doing.
Just a simple AB, single blind, no talking or cues.
6 runs of 10 switches, or not switched each times.
Good enough for me to know I statistically had no fkin idea which was playing.
Did the same with a topping pre 90 and bpbp, we could spot that easily, 9/10 most times.
Just a simple AB, single blind, no talking or cues.
6 runs of 10 switches, or not switched each times.
Good enough for me to know I statistically had no fkin idea which was playing.
Did the same with a topping pre 90 and bpbp, we could spot that easily, 9/10 most times.
Were they just ordinary DACs, or especially good ones?
I assume for the purposes of your test that the rest of the system was very good?
We seem to have stories going both ways so I’m just interested to find out more.
I assume for the purposes of your test that the rest of the system was very good?
We seem to have stories going both ways so I’m just interested to find out more.
My son and I used to play a game. We were always switching between Benchmark DAC-3 and my 2nd dac (which was ES9038Q2M playing DSD from AK4137). When I came out in the morning to the listening room, I would have no idea which dac was left hooked up by me or my son the day before. Blinded that way, they sounded pretty close to the same. However there was a little difference that I was able to memorize. My son couldn't memorize it, but he could hear it in short term A/B although he was still struggling. At first I found it hard to know which dac was left hooked up. Eventually, I could hear it every time although the difference was subtle.
This all was back when I would using NS-10 speakers and an old Bryston 4-B amplifier.
Today, with electrostatic speakers and a treated room, it would be trivial to tell the two dacs apart.
So what? I conclude that listener training matters, which is pretty much accepted fact in perceptual science. I also conclude that a system with poor resolution in many ways makes it harder to judge sound differences as compared to a close to SOA reproduction system.
Neither of those conclusions seems contrary to common sense nor to published research.
This all was back when I would using NS-10 speakers and an old Bryston 4-B amplifier.
Today, with electrostatic speakers and a treated room, it would be trivial to tell the two dacs apart.
So what? I conclude that listener training matters, which is pretty much accepted fact in perceptual science. I also conclude that a system with poor resolution in many ways makes it harder to judge sound differences as compared to a close to SOA reproduction system.
Neither of those conclusions seems contrary to common sense nor to published research.
People claim lots of things. Mostly non-leveled matched sighted evaluations which aren't even worth the time to do. I'm not very active on this forum, maybe people have some credible claims to good DACs sounding different.
We found that Benchmark DAC-3 and Topping D90 sounded distinctly different, including in terms of sound stage. This stuff has already come up earlier in the thread. I described the differences in detail. This was with trained listeners and according to our protocols.
It doesn't matter. If there is a tendency for people to hear what they expect to hear, then people who expect to hear no difference will hear no difference, even if there is difference. They will claim someone who does hear a difference has failed to level match and or any other excuse they can think of.
It doesn't matter. If there is a tendency for people to hear what they expect to hear, then people who expect to hear no difference will hear no difference, even if there is difference. They will claim someone who does hear a difference has failed to level match and or any other excuse they can think of.
Did you read a post from @tombo56 : https://www.diyaudio.com/community/...if-they-both-measure-well.418579/post-7813436
If they didn't level match not worth posting. Your described protocol is hardly excellent.
Just going from what is in the post, that tells me nothing at all.
Your response suggests to me that people who don't believe any difference is possible will reject evidence to the contrary. According to psychological studies, that's just what people do. They weight heavily evidence in support of their preexisting beliefs, and reject evidence to the contrary. Its just a manifestation of confirmation bias, which is a strong bias in all humans.
A more scientific response might be to suggest that maybe those two dacs are ones that Amir could compare in his controlled listening test study. I mean, that would be a reasonable response for someone who wants to know the truth.
OTOH someone who thinks they already know the truth won't want to risk the chance of finding out their truth turns out to be false.
A more scientific response might be to suggest that maybe those two dacs are ones that Amir could compare in his controlled listening test study. I mean, that would be a reasonable response for someone who wants to know the truth.
OTOH someone who thinks they already know the truth won't want to risk the chance of finding out their truth turns out to be false.
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You seemed to think Tombo56's post was meaningful. Why would consider that an indication just from what he posted?
BTW, it is not that I think no difference is possible. However, there are levels of performance for which DACs are not audible to any human listener. So beyond certain parameters no one is hearing a difference due to difference in the signal from the DAC.
No. A spectrum analyzer measures average volume level. Not phase. Not short term volume variations. Only an average. Okay?
The average can be right on. But the sound of a horn player vibrato on one dac is only frequency modulation. On the other dac there is volume level modulation too. However, the average volume level may be perfectly the same between both dacs (or even the same dac with different clocks). And I have heard exactly that.
Regarding level matching in that case, you can turn up and down the volume all you want. The volume modulation is either there or its not. Its not amplifier volume level dependent.
Therefore, a claim that PSS measurements completely describe dac performance under all dynamic conditions is an outlandish fairy tale.
Moreover, its not up to me to prove that Amir's theory is bunk. He needs to provide serious experimental evidence from a study properly designed to find the truth. Can he provide evidence in support of his theory. That means trying to prove the alternate hypothesis, which is that some dacs which measure similarly do sound different. When someone like @tombo56 identifies two dacs that might help prove the alternate hypothesis then its up to Amir to try to prove that tombo56 is right. If he makes a serious try and fails, then the evidence may weigh in favor of Amir's theory.
The average can be right on. But the sound of a horn player vibrato on one dac is only frequency modulation. On the other dac there is volume level modulation too. However, the average volume level may be perfectly the same between both dacs (or even the same dac with different clocks). And I have heard exactly that.
Regarding level matching in that case, you can turn up and down the volume all you want. The volume modulation is either there or its not. Its not amplifier volume level dependent.
Therefore, a claim that PSS measurements completely describe dac performance under all dynamic conditions is an outlandish fairy tale.
Moreover, its not up to me to prove that Amir's theory is bunk. He needs to provide serious experimental evidence from a study properly designed to find the truth. Can he provide evidence in support of his theory. That means trying to prove the alternate hypothesis, which is that some dacs which measure similarly do sound different. When someone like @tombo56 identifies two dacs that might help prove the alternate hypothesis then its up to Amir to try to prove that tombo56 is right. If he makes a serious try and fails, then the evidence may weigh in favor of Amir's theory.
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You'll need to give examples. You seem hung up on the FFT and steady state measurements. So we just trust tombo56 and that is it? Amir's view on things is not in conflict with how things work or how other electronics are designed and tested.
My post is honest answer to OP question. It is not proof of anything, as isn’t any other, in this thread, given listening experience example.
Right question is not if two well measuring DACs could be distinguished by sound, rather do two simple measurements like distortion and noise, with equal results, determine that equipment will be audibly indistinguishable. I’m not convinced. By my experience, it is not true even for simple devices like amplifiers.
To repeat, I’m an objectivist, measuring everything I can, because I’m well aware how unreliable our perception is. But, beside measurement gear, I do have ears and enjoy listening to music.
Off topic but interesting. You mean the Bruno Putzeys Balanced preamplifier don't you? Which of the 2 was the best one?
Topping Pre90 was on my list until I found out it has 2 kOhm input impedance while the BPBP is high ohmic. That might explain something. Even the not so wimpy sources may choke on 2 kOhm.
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Some more noise has been deleted.
If the signal remains this low the thread will be closed.
Suppose you have two DACs that you expect to sound exactly the same, but you are fairly open-minded about that. Without you knowing it, one actually has a 0.5 dB higher output level than the other. I could imagine that to your surprise, you will hear a difference then when you do a direct AB (or ABX) test.
The required level matching of 0.1dB actually makes proper AB comparisons of dacs quite challenging as the digital volume control in dacs typically has +/-0.5dB steps. Same goes for e.g. Windows sound control.
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