In which way are "distortion-free" and "totally transparent" related?
Is "transparent" not just a marketing term when attributed to an amplifier? What is the precise definition of this term?
The article is more an advertorial.
Is "transparent" not just a marketing term when attributed to an amplifier? What is the precise definition of this term?
The article is more an advertorial.
Yes it is a press release. There is also a tech review/testing of the Axign in a GaN amp, which is just a click away if you had read the release: https://audioxpress.com/article/fresh-from-the-bench-improving-gan-with-digital-control.
I think the term transparent is apt here; the goal is that whatever goes in, comes out unaltered. Transparent. That's a technical term for me.
A window can be transparent, all light goes through unaltered. Tech term. But yes, I agree it is sometimes (mis) used in advertising.
And being distortion free is only one requirement (there are more like flat frequency response, inaudible noise etc etc.).
Jan
I think the term transparent is apt here; the goal is that whatever goes in, comes out unaltered. Transparent. That's a technical term for me.
A window can be transparent, all light goes through unaltered. Tech term. But yes, I agree it is sometimes (mis) used in advertising.
And being distortion free is only one requirement (there are more like flat frequency response, inaudible noise etc etc.).
Jan
Last edited:
Isn't it an editorial piece from AudioExpress where, as usual, items are touted as fantastic, but in reality, its not. Non of the presented measuring data moves anything within class-d forward as I see it... perhaps only energy consumption but there where nothing factual (measurements) presented here... it just reiterates that it is in the system/board design that the performance lies and not necessarily in a wonder component/material...
From the article...
"Figure 7 shows the distortion spectrum for a 4R load with 220W. It’s dominated by the third harmonic at about -85dB, but is otherwise unremarkable. Likewise, a pair of 10V signals at 10kHz and 11kHz across an 8R load gives the intermodulation spectrum shown in Figure 8. The largest error is a sideband at -96dB; this is quite an excellent result."
- Figure 7 shows the distortion spectrum for a 4R load with 220W. It’s dominated by the third harmonic at about -85dB
A Hypex NcX500 is -110dB down at 220W 1kHz - thats 25 dB away from "next step distortion free and totally...."
- 10kHz and 11kHz across an 8R load gives the intermodulation spectrum shown in Figure 8. The largest error is a sideband at -96dB; this is quite an excellent result
The good ol' Hyp Nc400: -100dB in an "IMD spectrum at 18.5kHz+19.5kHz, 50W+50W. Peak voltage corresponds to a 200W sine" (from spec sheet) - half excellent but again not a "totally transparent amps" - and the design is what - 20 years old....
Franky Jan, I was a bit surprised you joined that publication - it seems to be advertising heavy and yes, press release editorial based heavy. And every single speaker driver benchmark test has had the summary: "... fantastic performance and solid engineering from xyz and its driver 0123..." - but looking at the data, nothing special was really measured... please don't make it a habit to rely ads from AX here... at least do it in the commercial sector if so...
//
From the article...
"Figure 7 shows the distortion spectrum for a 4R load with 220W. It’s dominated by the third harmonic at about -85dB, but is otherwise unremarkable. Likewise, a pair of 10V signals at 10kHz and 11kHz across an 8R load gives the intermodulation spectrum shown in Figure 8. The largest error is a sideband at -96dB; this is quite an excellent result."
- Figure 7 shows the distortion spectrum for a 4R load with 220W. It’s dominated by the third harmonic at about -85dB
A Hypex NcX500 is -110dB down at 220W 1kHz - thats 25 dB away from "next step distortion free and totally...."
- 10kHz and 11kHz across an 8R load gives the intermodulation spectrum shown in Figure 8. The largest error is a sideband at -96dB; this is quite an excellent result
The good ol' Hyp Nc400: -100dB in an "IMD spectrum at 18.5kHz+19.5kHz, 50W+50W. Peak voltage corresponds to a 200W sine" (from spec sheet) - half excellent but again not a "totally transparent amps" - and the design is what - 20 years old....
Franky Jan, I was a bit surprised you joined that publication - it seems to be advertising heavy and yes, press release editorial based heavy. And every single speaker driver benchmark test has had the summary: "... fantastic performance and solid engineering from xyz and its driver 0123..." - but looking at the data, nothing special was really measured... please don't make it a habit to rely ads from AX here... at least do it in the commercial sector if so...
//
That´s what the members at the "Church of SINAD" at that other forum believe. At which distortion level you call an amp "transparent" (and no, it´s not a technical term in the context of amplifiers).
I joined as Technical Editor and my task was to increase technical content.
Surely you must have noticed the increase in tech content.
I want to do more but it's hard to do, and sometimes not as good or quick as I would want.
I'd hate to see the last technical dedicated audio magazine slowly disappear ...
Jan
Surely you must have noticed the increase in tech content.
I want to do more but it's hard to do, and sometimes not as good or quick as I would want.
I'd hate to see the last technical dedicated audio magazine slowly disappear ...
Jan
It's journalism, it is allowed to have a few words that don't fall into technical linguo (on top of it being press release). And it's often difficult to write an article that will go trough internal critique. If you prefer to read otherwise, i suggest you read research papers 🙂 In any case, there is solid amount of tech within the scope of whats interesting to us as audio affectionados.
Sorry Jan. The articles and papers claim multiphase operation but make no mention of filter current sharing other than a reference to someone elses research and there is no indication that they have attempted to implement this. You can actually see the fail in some of the graphs. Also, for me, the most pernicious audio ******** fail I can find in that pile of marketing drivel is a claim that output ripple is -70dB and this is in effect from a 2 phase system. You only get that for specific modulation levels, in this case zero output. 2 phases might get you a -3dB improvement over the complete range but fancy bollocks boys making up unsupportable claims for their fantasy bollocks in the expectation that no-one will notice just gets up my nose. Especially when they refer to their own research papers with graphs of multiphase operation that will tell you that their marketing ******** is wrong
- Home
- Amplifiers
- Class D
- The next step to distortion-free and totally transparent power amps