Can someone explain what can we see on this graph and what does "Yes, there is rise in higher frequencies but we are starting at such a low baseline that this is exaggerated compared to other amplifiers." mean?
I currently use a IcePower 125ASX2 amp and my biggest problem with it is the same graph:
Or alternately the same graph from the spec sheet:
I looked at Class AB reviews of AHB2 and Modulus 286 and those graphs were not made. Is this something which is only "bad" with Class D? Should I be concerned about it?
I currently use a IcePower 125ASX2 amp and my biggest problem with it is the same graph:
Or alternately the same graph from the spec sheet:
I looked at Class AB reviews of AHB2 and Modulus 286 and those graphs were not made. Is this something which is only "bad" with Class D? Should I be concerned about it?
So you are saying that at 5 kHz for example, this list would look totally different?
Amplifier SINAD list ASR + 3rd parties - Google Sheets
Amplifier SINAD list ASR + 3rd parties - Google Sheets
True, but the max size here is 18mm (D) x 35,5mm, the Mundorf MLGO serie won't fit ) I think the best choice for the moment is the Nichicon KW 3300uf - 50v that has the same body as the stock one.
You re correct... take a look at the Amplifier Sinad list from ASR :
Amplifier SINAD list ASR + 3rd parties - Google Sheets
We only consider the THD+N 5W / 4R as a point of reference ...
This puts the Orchard Starkrimson Ultra for example @ the 34st rank ! While the manufacturer's measurements have never been considered on ASR strangely ....
Yes but 95% of the readers only look at the 5W/1khz SINAD number. They don’t look beyond that when making their purchase decision. It’s clear by the comments after all the reviews. By doing this companies like Topping only need to tune their amps to have a great number at this specific spec. And they take the lead on the list.
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That's not apples-apples though. Says right there on the chart that it's using a 20kHz measurement bandwidth, whereas the ASR tests are at either 45 or 90kHz. The ASR test of the Purifi at 90kHz bandwidth shows rising THD+N above 5kHz as well.
https://www.audiosciencereview.com/...quency-vs-power-audio-measurements-png.28865/
The Purifi does do significantly better - particularly considering that the Topping was measured at 45kHz - but your position seems to be "if it isn't as good as the Purifi it's a worthless piece of crap" which is ridiculous.
Rising THD+N with a wide bandwidth out of the range of human hearing gives a flawed result when measuring class D amps. Because the harmonics that cause the rise in distortion are out of the band of human hearing.
I’m not saying it’s total crap, but certainly not the 2nd best amp in the world. Like I said earlier, slightly better than the $35 Icepower 100AS2 amp based on the same class D chip.
I’m not saying it’s total crap, but certainly not the 2nd best amp in the world. Like I said earlier, slightly better than the $35 Icepower 100AS2 amp based on the same class D chip.
It really is too bad that "1kHz SINAD" seems to have been adopted as a singular figure of merit. I think ASRs tests are good, but are definitely undermined by resorting to that ranking.
IMHO any 'figure of merit' is an oversimplification, but of all the ASR tests I think the multi-tone IMD is the best 'single chart' test. It hasn't been done for all devices though, and given that it's a chart over frequency it doesn't lend itself to distilling down to a single 'figure of merit' for ranking purposes. He didn't run that test for the Purifi, which is too bad - I'd expect it would have aced it.
Well, you can't really have it both ways - criticize the amp for a measurement showing rising THD+N over 5kHz and then turn around and claim it's a meaningless test.
Well. First, the PA5 is ~10dB better in THD+N which would seem to be a bit better than 'slightly' - the Purifi doesn't beat the Topping by much more than that in 1kHz THD (ignoring N). Second, the 100AS2 is $70+ each qty 20, or $155 for a single piece, and you still have to add a case and associated hardware. https://icepower.dk/buy/as-series/100as2/ . Maybe the price plummets in production quantities, but that's not particularly relevant to this audience - You'd be in the same price ballpark for a finished unit.
I get your main point - the Topping isn't the 2nd best amp in the world, and I don't disagree. It does seem to be a real step forward for budget amps though.
Lars explained the test to use earlier in this thread. 2 tone at 18/19khz. One I do myself is a THD+N 2 tone with 1 tone @ 1khz, and 1 @ 15khz. Then compare with a single tone at kHz. The difference in the results shows the contribution to in band noise and distortion caused by the 15khz tone.
Sorry I was thinking about 100 piece pricing.
Sorry I was thinking about 100 piece pricing.
Thanks, juste sharing a passion : nothing else.
what is funny in the majority of the forums where I evolve is that when I give ASR measurements ... people complain because the measurements do not always reflect reality ... and when I let my ears speak, I am told that I have no supporting measures ...
In any case, it's really stupid that I'm not in the USA ... I would have made you discover some class D amps unknown in the USA and which for me give me much more pleasure than my Purifi and other amps I own
But talking about TPA325X boards, I am confident that in this batch of TPA325X; one of these modules could hide surprising measurements but unfortunately I have never been able to measure them. Some really look like the PA5 and all are fully balanced (If I am not wrong, the last is using air core inductors)
what is funny in the majority of the forums where I evolve is that when I give ASR measurements ... people complain because the measurements do not always reflect reality ... and when I let my ears speak, I am told that I have no supporting measures ...
In any case, it's really stupid that I'm not in the USA ... I would have made you discover some class D amps unknown in the USA and which for me give me much more pleasure than my Purifi and other amps I own
But talking about TPA325X boards, I am confident that in this batch of TPA325X; one of these modules could hide surprising measurements but unfortunately I have never been able to measure them. Some really look like the PA5 and all are fully balanced (If I am not wrong, the last is using air core inductors)
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In a properly configured system, an amplifier shouldn’t add pleasure. It should simply amplify the signal it’s fed in the most linear way possible. If the Purifi doesn’t bring you the most pleasure the problem is one or both of these 2 issues:
1: You have a poor Purifi implementation.
2: You don’t like the sound of the source gear feeding the amp.
1: You have a poor Purifi implementation.
2: You don’t like the sound of the source gear feeding the amp.