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In Reply to: RE: High end audio = musical accuracy, you must be kidding! posted by KlausR. on January 31, 2008 at 07:38:59
"geschalteten Versorgungsspannung"
Doesn't this mean Switched supply voltage?
"geringen Verlustleistung"
Doesn't this mean small energy dissipation? As in LOW bias??
Sounds like a switched mode power supply with a low bias Class B stage or Class D to me.
"This spec is averaged over the range 100 Hz - 6 kHz.
"
The spec is RUBBISH!! Look at the measurement, the speaker can only reach over 120db from 200Hz to 1Khz. Above 5Khz and below 100Hz it cannot even get to 110db.
"The S'phile measurements don't indicate at which distance it was measured, so I presume it was at 1 m. The measurements for the O500C were done at 2.1 m"
The point is the SPL level vs. distortion level. Its relative and distance is not really an issue so why bring it up? The change in level for both the distortion and the main signal will be the same with distance. Your speaker loses here big time.
" The figures in detail: given the fact that Wilson is measured at 96 dB/1m and mine at 100 dB/2.1m a meaningful comparison is not possible"
Look again Klaus, the numbers I gave you were for 106db! Yes they did 106db also in that review as I said read it again.
"Given the fact that the O500C do NOT deliver 20 Hz, let alone 18, no data are available for frequencies below 30 Hz."
Completely irrelevant! Given the high distortion at 30Hz or even 50Hz do you really think it will be better at 18Hz? For sure your speaker will try to reproduce 18Hz if you feed it 18Hz but it will probably ONLY make distortion. Probably you will get a LOT of 36Hz and 54Hz instead LOL!
"At 18 Hz and 106 dB/1m the Wilson produce -40 k2, mine at 60 Hz and 100 dB/2.1 m (which is roughly the same under anechoic conditions) produce - 48 k2.
"
BIG difference, Klaus, huge in fact. First it is MUCH lower in frequency (and the X1 is about -70db at your frequencies) and it is 6 db higher in level, also a big difference. Also, the measurements on K&H website show about -28 db not -48 db, learn to read a graph Klaus. Notice also that below 30Hz the distortion shoots off the top of the graph!! Now that's distortion (and not unusual for a vented design).
Clearly you should simply concede this point that your speaker is NOT at all lower in distortion than the X1 in bass or anywhere else for that matter.
"How much do the Wilson cost, $100K?"
It was about $85,000 not $100,000
"Further, how do these figure relate to thresholds of detection?"
Well clearly at 100db your speaker will be audibly distorting the bass and the X1 not. Simple as that.
"The graph on the linked page says, "anechoic response on tweeter axis at 45" (solid curve)" and the curve is flat ± 3.5 dB as compared to ± 1.5 dB for mine.
"
Look at the bottom graphs, Klaus. The ones that say in-room response. See them? Now look closely at the y-axis and you will see it is +-2.5db over the range I am talking about IN-ROOM. No one cares about the anechoic response and only on-axis. Meaningless specsmanship.
Even the quasi-anechoic measurements in Stereophile are averaged over a 30 degree window and so they too are not purely "on-axis" measurements but already somthing more useful. You should learn to read these things better Klaus.
"I'm not teaching you how to read such graphs. The central question is NOT wide or narrow dispersion, but how even/smooth the off-axis curves are"
No, I should be teaching you because of all the things you have either on purpose or on accident overlooked. Wide dispersion in a room IS an issue, mandating room treatment in most cases.
I have shown you that your speaker is not significantly superior in frequency response and inferior to a top of the line High end speaker in distortion (also in dynamic capabilities I am sure). So stop with the BS that high end speakers are all inaccurate!
Stay factual and we talk. Stay on your current level and I remain silent. Simple as that. Over and out.
Klaus I have stayed very factual. Going back over I correct you point by point by point, addressing mistakes you have made like -48db distortion at 50hz and 100db when its really -28db and that the spec for 123db really only applies from 200-1000 Hz while the rest is around 110 db or less.
I have also pointed out, correctly that the high end speaker I chose fits +- 2.5db in-room while you have only an on-axis anechoic measurement for comparison.
What else? Oh yeah your claim that high end speakers are inaccurate has been shot down. I also gave you the phrases in German that show switching power supply and low bias. Now if you can't see these things in the graphs provided by K&H and in STereophile, I would be happy someday in the future to point them out to you in person.
Rubbish, BS and similar terms is not what I would call factual! Such terms are not convincing arguments either!
Some of your points:
You said: "As you can see even at 18Hz and 106db the Wilson X1 has lower distortion than your speaker at 60Hz and 100db."
Wilson: 18 Hz, 106 dB/1m, k2= -40 dB, k3= -47 dB
O500C: 60 Hz, 100 dB/2.1 m: k2= -25 dB
So yes, the Wilson is better than the O500C, but the O500C has one 12" woofer, the Wilson has one 12" + one 15" woofer. If we compared like with like we'd take the O900 subwoofer with its two 12" drivers (which is still smaller than the Wilson). However, no distortion data except from -46 dB THD at 30 Hz, 101 dB/1m.
You say: "I have also pointed out, correctly that the high end speaker I chose fits +- 2.5db in-room "
Yes, in Colloms' room, best placement. The other position in that room is more like ± 5 dB. And in Franassovici's room, the response is ± 3 dB.
Obviously, the in-room response depends entirely on room size, reverberation time, where you place the speakers and where you measure. Therefore, in-room curves are simply meaningless for comparison purposes. The only curves you can reasonably compare are anechoic and here the Wilson do not win. Plus, the sound field in small rooms is direct sound + early reflections, so I'd like to see off-axis graphs for the Wilson.
You said: "They have at the very least switch mode power supplies. I also gave you the phrases in German that show switching [mode] power supply..."
FYI, switch mode power supply in German is "Schaltnetzteil". Does a switch mode power supply need a 1200 VA transformer?
You said: "It's right there in the measurements by K&H!! 30 degrees at high frequency is pretty wide actually."
If you compare the graph with the graph for the Summa, you see that at ±30° the Summa too is within the same 3-5 dB window up to 20 kHz. Such The ±30° listening window you will probably find with most studio monitors because the sound engineer needs some freedom of movement in the horizontal plane.
Overall the Summa is a bit narrower, but that is a matter of design philosphy. Geddes favors narrow dispersion, Moulton favors wide dispersion, who's right, who's wrong? So far I haven't seen many published psychoacoustic research where dispersion patterns have been investigated. What counts is how the off-axis curves behave and for both speakers they behave very well.
Klaus
"Rubbish, BS and similar terms is not what I would call factual! Such terms are not convincing arguments either!"
Oh but Klaus I go on to explain quite clearly why they are rubbish, BS and so on.
"If we compared like with like we'd take the O900 subwoofer with its two 12" drivers (which is still smaller than the Wilson). However, no distortion data except from -46 dB THD at 30 Hz, 101 dB/1m"
Yes so 5db lower in level and about the same distortion but a full octave higher. Not so convincing Klaus.
Now let me ask you, how much does a system composed of the 0500C and the 0900 cost?? Are we getting close yet to the price of the Wilson? I bet we are. Are the cabinets anywhere nearly as well constructed as the Wilsons (which aren't even wood at all but high density resin/rock that cost probably 10 times as much as MDF)? Not likely.
"Yes, in Colloms' room, best placement"
Well what else would you knowingly use?? Honestly.
"And in Franassovici's room, the response is ± 3 dB"
Also very good in-room response with no DSP involved.
All this banter is nice, Klaus but my point was to debunk your comment about high end speakers not being accurate. Consider it debunked. Geddes Summa also measures quite well FWIW.
The simple use of such terms does not mean that you are right and I am wrong. There is more to a convincing argument than just impolite terms.
> Yes so 5db lower in level and about the same distortion but a full octave higher. Not so convincing Klaus. <
Of course it's not convincing, you have THD ate 30 Hz on the one hand, k2 at 18 Hz the other hand. Apples and oranges.
> Now let me ask you, how much does a system composed of the 0500C and the 0900 cost?? <
Well, the 500 is about 9,600 Euros, the 900 about 2400. Makes about 13,000, hence 26,000 for a stereo set. Add two power amps (I think K+H's 2000 Watts amp was at about 2000 Euros), makes 30,000 Euros for the set. In todays dollars that is 44,000. You said the Wilson cost $85k? Well, that's almost twice the price and you still need preamp and power amps. And if you feel the need to apply EQ, you'd need another 2,500 or so for a Tact.
> Are the cabinets anywhere nearly as well constructed as the Wilsons (which aren't even wood at all but high density resin/rock that cost probably 10 times as much as MDF)? Not likely. <
There is more to cabinet design than just stiffness and rigidity:
Bastyr, "On the Acoustic Radiation from a Loudspeaker's Cabinet", JAES 2003, p.234
The O500C use waveguides, something you probably could not make from Wilson's X-stuff. The cabinet itself is MDF or similar, but then it's substantially smaller than the Wilson so radiating surfaces are smaller and structural modes are at higher frequencies, mayv=be even above the working range of the bass drivers.
> Also very good in-room response with no DSP involved <
You conveniently forget the ± 5 dB in Colloms' room. + you don't know, and neither do I, how the 500 would measure in these rooms.
> All this banter is nice, Klaus but my point was to debunk your comment about high end speakers not being accurate. <
When I look at anechoic data, the Wilson is the clear loser. So no, for me you did not debunk anything, your POV on this matter is simply a different one. I can assure you, had I found a hifi speaker in that price range that met my criteria, I possibly would not have started looking elsewhere. But I didn't.
And yes, the Summa measures extremely well, in my eyes it's more accurate than the Wilson, I would prefer it to the Wilson anytime.
Klaus
> Well what else [speaker placement] would you knowingly use?? Honestly. <
If youre married, ask your wife? She'll tell you!!!
"Of course it's not convincing, you have THD ate 30 Hz on the one hand, k2 at 18 Hz the other hand. Apples and oranges.
"
No Klaus, it is not apples and oranges, we are talking about bass distortion in two different speakers. Apples to apples. It is clear from inspection that the bass distortion of the X1 is far superior.
"The cabinet itself is MDF or similar, but then it's substantially smaller than the Wilson so radiating surfaces are smaller and structural modes are at higher frequencies,"
Wrong again Klaus, the X1 has a separate mid/high module that is completely a separate entity from bass module. So, not only are the panels extremely rigid and dense and free from the kind of vibration transmission of Mdf and the like, the upper section will not be influenced by the bass.
FWIW, the cost of cabinet materials in the X1 is many times the cost of the cabinet materials in the K&H speakers.
"You conveniently forget the ± 5 dB in Colloms' room. + you don't know, and neither do I, how the 500 would measure in these rooms."
No I did not and its +- 2.5db in his room over most of the FR. You are right I don't know how the K&H speaker would measure but I know that the Wilson's measurement is considered to be quite good from other measurements and my own experience measuring speakers in my own room.
"When I look at anechoic data, the Wilson is the clear loser. So no, for me you did not debunk anything, your POV on this matter is simply a different one"
Nonsense Klaus, the ONLY clear advantage your speaker has is on-axis FR. It is demonstrably lower in distortion and goes much deeper in the bass on top all the while staying much cleaner. Its in-room response indicates a suitably even off-axis response, which is a very good response. Anechoic data is NOT in-room response and less meaningful.
"And yes, the Summa measures extremely well, in my eyes it's more accurate than the Wilson, I would prefer it to the Wilson anytime."
So yet another home speaker that is "accurate". I find it laughable though that you would choose it over the Wilson without hearing either one first. You would pick it strictly from the measurements? I shudder to think how your system must sound.
"If youre married, ask your wife? She'll tell you!!!"
Does this mean you have them built into the walls like in a studio??
You are comparing THD to k2 and this at different frequencies!
For the other distortion data, Wilson is measured at 85dB/1m, 96dB/1m and 106dB/1m, the O500C was measured at 95dB/2m (review) and 100dB/2.1m (website) so a meaningful comparison is possible. The O500C were measured under anechoic conditions, where SPL decreases like in free field, i.e. 6 dB when distance doubles. Where were the Wilson measured? Anechoic or in Colloms' room, where SPL decreases 2-3 dB when distance doubles. If it is in Colloms's room, again, you can't compare because for the same SPL the loudspeaker has to work less hard.
If I look at the Wilson, the bass cabinet seems to be about half the total height, which would make a cabinet of 90x42x63 cm, whereas the O500C is 75x40x44 cm. The Wilson's side panel is about 1.7 times larger. Unless you measure the amount of acoustic radiation by the panels you can't know. The drivers in O500C are sealed at the rear, so bass frequencies have no effect.
> Nonsense Klaus, the ONLY clear advantage your speaker has is on-axis FR <
There are no off-axis measurements for the Wilson, so you don't know. Impulse response and waterfall are less good than for the O500C.
> I shudder to think how your system must sound <
You seem to be sure that a system selected on the basis of measurements alone must sound bad? Be assured, it sounds as it is supposed to sound, crystal clear, neutral, controlled.
Klaus
"You are comparing THD to k2 and this at different frequencies!"
Klaus, you are really being silly here. They are showing the whole spectrum with K2 and K3 well below what your speaker achieves. The rest is negligible at below -70db. Also, the frequency of 18Hz is MUCH more difficult to do cleanly than 50Hz. MUCH. So if anything it makes your speaker come off even worse in the comparison as it is clear by 18Hz your speaker will have abotu 100% distortion and the only thing we would hear are K2 and K3 (ie. 36 and 54Hz).
Besides they also show the data for higher frequencies.
For example at 100Hz:
"Over the 86dB-96dB range and up to the highest 106dB loudness, the X-1's third harmonic remained unchanged at around 0.1% (-60dB). Not unexpectedly, the second harmonic progressively lost ground as the spl increased, but this was to a still-state-of-the-art 0.2% (-54dB) at the highest test level (fig.3). "
At 1Khz:
"With a 1kHz tone at 96dB, there was a mild increase in third-harmonic distortion to -50dB, with the second still better than -65dB. Moving into the treble range, to 5kHz, the upper 96dB test level resulted in a truly negligible amount of second harmonic (-66dB, 0.05%), and everything else was down at -70dB or better—another great result (fig.4). "
At 24Hz:
"At 106dB, the X-1 was still kicking hard, the second harmonic of the 24Hz tone lying at -32dB, the third at -27dB. Many big speakers have low-frequency distortion more than 40dB higher at this point; in other words, the distortion power is greater than the fundamental—a phenomenon called "doubling." "
That doubling is what your speakers would be doing at 24Hz, Klaus.
At 18Hz:
"By this time I was fully confident of the X-1's abilities, so drove it with an infrasonic 18Hz fundamental at a nominal 106dB sound-pressure level (fig.5), the latter referenced to the level at 24Hz. I found that genuine high-power output was possible into the ultra-low bass. Even with the punishing 18Hz signal, the second harmonic was quite inaudible at -40dB (1%), with the third very low at -47dB (0.4%)—a quite remarkable performance. Well, the experts always told us that for good bass you needed a big box and big cones; you certainly get them with the X-1!
"
Like I said, your speaker can't touch this.
"Where were the Wilson measured? Anechoic or in Colloms' room, where SPL decreases 2-3 dB when distance doubles. If it is in Colloms's room, again, you can't compare because for the same SPL the loudspeaker has to work less hard.
"
Give me a break Klaus, you are splitting the hairs so fine as to be ridiculous. If you like then the 100db from K&H is quite close to the 106db from Wilson review and your speaker STILL loses by a mile (or kilometer if you prefer).
"The Wilson's side panel is about 1.7 times larger"
And probably 10 times as stiff.
"This excellence extended to the vibration performance of the Grand SLAMM's enclosure. I probed several locations on the three upper-range modules and the bass enclosure with my low-mass B&K accelerometer, but it proved very hard to find anything of significance. The worst part of the largest panel of one of the midrange modules still had a desirably smooth output.
Very little vibrational energy emanated from the bass enclosure over its nominal 20-500Hz working band (fig.16). There was some vibrational output above 900Hz, but this was merely a low-level signal derived from the point contact with the stack of upper modules.—
"
Cabinet vibration from the bass is between -35 to -42db down from the frequency sweep level. This is SOTA just look at the graph, Klaus or did you miss that one?
"Unless you measure the amount of acoustic radiation by the panels you can't know. The drivers in O500C are sealed at the rear, so bass frequencies have no effect.
"
The measurements in the review, Klaus. I don't know what you mean by the statement of the woofers being sealed means. It is a vented speaker system is it not?
"There are no off-axis measurements for the Wilson"
Not true again, Klaus. An in-room measurement is the sum of the on-axis plus ALL the off-axis response. So it is included in that measurement.
Plus: "Fig.8 Wilson X-1/Grand SLAMM, horizontal (top) and vertical (bottom) response families at 45", normalized to response on tweeter axis. Dotted curves are -7.5 degrees vertical and 15 degrees horizontal; dashed curves are ±15 degrees vertical and 30 degrees, 45 degrees, and 60 degrees horizontal. "
What do you call this?
"Impulse response and waterfall are less good than for the O500C"
Well the impulse response is incomplete for the Wilson but what there is isn't bad at all. Yours achieves good impulse response strictly from DSP. THIS is apples to oranges Klaus!
As to the spectral decay, the Wilson has decayed below -20db in about 1.3 ms. The K&H about the same. I see no decisive advantage for your speaker there.
"You seem to be sure that a system selected on the basis of measurements alone must sound bad"
Heard enough of them to know that it isn't all about measurements and if you bought without listening first then well...
"Be assured, it sounds as it is supposed to sound, crystal clear, neutral, controlled"
I have heard enough so called "crystal" so called "clear" so called "neutral" (yes I know the German audiophile idea of neutral and believe me its not) and so called "controlled" to know that most of the time it is unnatural, lacking harmonic content, flat soundstage, overdamped etc. etc. Maybe yours is not but my experience tells me otherwise.
Nevermind though because the whole point of this part of this thread was to debunk your comment about high end loudspeakers not being accurate and I have now presented TWO speakers (the X1 and the Summa), which are measurably quite accurate. Whether or not they are MORE accurate than yours is academic because they both give excellent objective measurements even by your DSP "fixed" speakers standards. Thus your claim of inaccuracy has been debunked.
Hip, hip, hooray, bravo, what an achievement!!! Only, I can’t find that passage in MY book!
Meaningless comparisons are not my piece of cake, so I'm ending the discussion here and now.
Klaus
As long as you stop spreading misconceptions, Klaus, then I have achieved my goal with this debate.
Oh shut up and go change your armour.