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The damping factor and the sound of real music
On Dec 26, 12:49 pm, "Dave Plowman (News)"
wrote: In article , tony sayer wrote: In an attempt to improve both the LF extension and spl stacking is sometimes used and I can see that that would be fine with the 57 variety. What about your 63s? Presumably you would have to arrange them such that they form part of an outer circle otherwise their concentric rings and imaginary point source behind the speakers will be rendered useless? Unless you must have it louder there wouldn't be any point and as said the point source will be sodded up.... I've oft wondered about that. My actual experience of electrostatics is limited in depth to the original Quad design. And those had perhaps the most critical sweet spot of any speaker, but when in it had excellent imaging. I never did have an opportunity to live with a stacked set up to really decide how well it worked. Well, I had stacked ESL57 for years, and perhaps everyone should experience them once but stacks are not the end-all and be-all of stats; I'm just explaining to Poopie how it is done with the round- form diaphraghms like the ESL-63 because he doesn't appear to have the brains to work it out. The 57 is tricky to stack right; you can as easily muddle your sound as boost its volume. You stack ESL-57 one on top of the other, the top one turned upside down and angled towards the bottom one, the entire assembly pivoted around the joint towards the listening chair, ditto for the assembly on the other side. Each assembly is also angled inwards in relation to the side wall to face the listening chair squarely (line from the listening chair to the radiating face hits it perpendicularly). Now you're looking at four imaginary lines making a pyramid towards the listening chair. It helps to get the four lines the same length if you raise the assembly on each side several feet and tilt it over towards the listening chair. As by now you suspect, stacking ESL57 turns your music into a perfectly lonely pastime; the sweet spot becomes hypercritical in three dimensions. I kept stacked ESL for years because mine was aimed at my work chair in front of my computer, in which I sat in the sweet spot for hours. Visitors to my study had only a partial experience of the music... For years I also had a singleton 57 from some old chappie who read my music column; it came complete with correspondence in Peter Walker's own hand which I still have. Sometimes for months on end I would play just the single 57, and not because I was moving around, quite the contrary: I was sitting at my desk for 16 hours every day grafting away on a big book. I remember that as one of the sweetest musical experiences ever, a really good reason to go mono; that is still my reference of the purest, most angelic sound I ever heard. Soundstaging is really a rather trivial trick, and the only one stereo offers for what is often a very high price in its associated downsides; it is a party trick for "audiophiles" who have no real interest in the enjoyment of music. Andre Jute Visit Jute on Amps at http://members.lycos.co.uk/fiultra/ "wonderfully well written and reasoned information for the tube audio constructor" John Broskie TubeCAD & GlassWare "an unbelievably comprehensive web site containing vital gems of wisdom" Stuart Perry Hi-Fi News & Record Review |
The damping factor and the sound of real music
On Dec 26, 12:00*pm, tony sayer wrote:
In article , Bob Latham bob@sick- of-spam.invalid scribeth thus In article , * Jim Lesurf wrote: In article , Eeyore wrote: On the ESL63 the resulting LF roll-off is -6dB at about 35 Hz, roughly second order IIRC. This, of course, is the nominal 'free space' value. In the room I use for the main hifi system the last time I measured it was only about -3dB at 30-35Hz. The result does not sound 'bass light' to me. But this will of course depend on the room, etc, and the absence of a box boom may make other speakers seem to have 'more bass'... *:-) It may be more significant that the sound pressure level you can get at low frequencies is perhaps more restricted than a good conventional speaker of similar price. But that is a question of sound power, not frequency response. In an attempt to improve both the LF extension and spl stacking is sometimes used and I can see that that would be fine with the 57 variety. What about your 63s? Presumably you would have to arrange them such that they form part of an outer circle otherwise their concentric rings and imaginary point source behind the speakers will be rendered useless? Cheers, Bob. Unless you must have it louder there wouldn't be any point and as said the point source will be sodded up.... -- Tony Sayer It depends what you're doing whether "the point source will be sodded up". For instance, Bessel is a form of stacking in which the point source, far from being "sodded up" is enhanced. For another, several of the stacking schemes for ESL63 and similar (for which it becomes even less necessary, but I'm just humouring Poopie because it is Christmas) I explained are for very grand or even public rooms, in which a tiny loss in potential quality will not be noticed because no one will sit down to listen for it, and the overwhelming quality of the stats *will* be noticed. For yet another, it is easy to stack the ESL63 and derivatives in pairs so that the point source of one precisely meets the point of origin of the other, which is only notionally possible, and only at one listening point, for any other type of speakers (especially multiple cones!), the upshot being that ESL-63 is probably the most stackable speaker there is... Andre Jute Visit Jute on Amps at http://members.lycos.co.uk/fiultra/ "wonderfully well written and reasoned information for the tube audio constructor" John Broskie TubeCAD & GlassWare "an unbelievably comprehensive web site containing vital gems of wisdom" Stuart Perry Hi-Fi News & Record Review |
The damping factor and the sound of real music
"tony sayer" wrote
Yes but that was the ESL57 series and quite well that worked, but the modern designs are sufficient for purpose if you want to hear what really went on;)... Not according to the "Hi-Fi Choice" article I read in the late 80s. It had a picture of his room, and in it were (at least) 2 pairs of stripped-down (grilles removed) ESL-63s, arranged so that for each channel there were 2 speakers right next to each other, but set at 90 degrees to each other. I forget his name right now but I know it's still somewhere in my memory. Oh yes, "ARA", I think. Alastair Robertson-Aikman or something? Martin -- M.A.Poyser Tel.: 07967 110890 Manchester, U.K. http://www.livejournal.com/userinfo.bml?user=fleetie |
The damping factor and the sound of real music
Andre Jute wrote:
... For yet another, it is easy to stack the ESL63 and derivatives in pairs so that the point source of one precisely meets the point of origin of the other, which is only notionally possible, and only at one listening point, for any other type of speakers (especially multiple cones!), the upshot being that ESL-63 is probably the most stackable speaker there is... Do please elaborate, Andre. We could do with some education today. -- Eiron. |
The damping factor and the sound of real music
Hey, Jim, this is my thread which I started and shared with UKRA for
edification and laughter. It's a bit mean of you, in this season too, to grab it all for yourself by editing the distribution list, thereby depriving us of your great wisdom and knowledge, especially when you're in agreement with me, thereby affirming your great wisdom and knowledge. On Dec 24, 12:05 pm, Jim Lesurf wrote: In article , Eeyore wrote: Electrostatics may indeed have less colouration than most speakers but that has nothing to do with the bass. The absence of any meaningful baffle means the electrostatics will always have poor bass repsponse. It's inherent to the design (the rear radiation cancels the front radiation more at low frequencies determined by its physical size). On the ESL63 the resulting LF roll-off is -6dB at about 35 Hz, roughly second order IIRC. This, of course, is the nominal 'free space' value. In the room I use for the main hifi system the last time I measured it was only about -3dB at 30-35Hz. The result does not sound 'bass light' to me. But this will of course depend on the room, etc, and the absence of a box boom may make other speakers seem to have 'more bass'... :-) I am always amazed (and entertained by their stupidity, er,,, on Christmas day I mean chutzpuh) of people whose own speakers bottom out around 100Hz lecturing me on how my Quad ESL-63 are "bass light" because they heard some other clown say it. (Dave Plowman already made the point about most people's idea of bass being around 100Hz. Gordon Rankin, the American amp designer, once made the point in a discussion of designing boxes for Diatech speakers that the cleanest sound is by rolling them off at about 60Hz rather than the 10 or even 15Hz lower that was then the mode. I tried it. Wonderful sound for box speakers; made the more normal designs sound wretched. On another occasion I was trying a crossover point on 57s to woofers of 110Hz and somehow in a listening session, the woofer wasn't operating -- I swear I didn't do it on purpose -- and none of my panel of self-declared audiophiles, though none of them with electrostats at home, noticed a thing...) It may be more significant that the sound pressure level you can get at low frequencies is perhaps more restricted than a good conventional speaker of similar price. But that is a question of sound power, not frequency response. It is worth saying that Quad stats, in a room say smaller than 3000 cubic feet, *will* damage your ears, and the more so if you stack them correctly to enhance the bass, because the bass is enhanced more than the mid- and high-frequencies. What happens on a stat is that bass is so clean that you think there is less of it, you turn it up, there isn't the grunge expected from boomboxes which also acts as a level- signal, you keep turning it up, and the actual sound energy reaching your ears is much higher than you would permit with a boombox. I became very aware of this when I bought a STAX electrostatic earphone as a gift for myself last Christmas. In test, trying to level-match B&O, Sennheiser and STAX headphones, I discovered that I used the STAX consistently 2dB and more above the level of the conventional driver headphones. I don't have a dummy measuring head, so my numbers may be a bit of a kludge, but the tendency is clear, and the reason is the clean bass, the absence of warning signals included in lower quality bass. Slainte, ****ing outside in the green and beloved island. I was planning a ride on my bike this afternoon. Oh well... Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.audiomisc.co.uk/index.html Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html May you never come to the notice of the authorities! Andre Jute Visit Jute on Amps at http://members.lycos.co.uk/fiultra/ "wonderfully well written and reasoned information for the tube audio constructor" John Broskie TubeCAD & GlassWare "an unbelievably comprehensive web site containing vital gems of wisdom" Stuart Perry Hi-Fi News & Record Review |
The damping factor and the sound of real music
I'll get into it with Andre one more time as I tire his cheap
uniformed shots at audio engineers. As usual, part of what Andre writes (here and on his website) is slightly correct, but much of it misleading and uninformed half truths. He is a self appointed expert without the benefit of an audio engineering education and is more often wrong than right. Every forum needs a clown to keep it entertaining, and Andre without his vitriol would fit the bill nicely. A couple of caveats: Andre and I have got into it before and I've endured his personal attacks which don't bother me. He knows my qualifications and hopefully won't waste time questioning them again. Only one of us is a member of the AES, SMPTE, and ASA. I've also been a big Quad fan my entire adult life, which means I've owned and (and repaired) Quads since 1976, including 57's, 63', 988's, 989's. I've also listened to the new 9805's for roughly eight hours of listening time. Toured the Huntington factory three times (twice with Peter Walker, once with Ross) before it closed. I am listening to a Kate Bush CD on 988's as I write this... The traditional calculation of damping factor is a ratio of the total impedance of the speaker divided by the total impedance to the speaker system being driven. Both vary with frequency, especially the speaker complex impedance. Assuming a given amplifier with a fixed impedance of 0.1 ohm across its power output (a huge assumption, especially with tube equipment), we only have to deal with the three other impedances associated with the speaker: acoustic, electrical, and mechanical of the speaker cable, speaker, and listening environment. The last two vary across the entire listening spectrum rather radically. Most audio engineers don't waste time calculating damping factor anymore as the number is somewhat meaningless from a comparative standpoint. Just the static electrical/mechanical impedance of a Quad 57 can be seen on this website: http://www.quadesl.com/quad_main.shtml. You tell me how to provide a single number based on that impedance graph, let alone with the acoustic impedance of the room added. The simple answer is you can't. Calculating these three impedances is impossible, although it can be measured fairly easily with B&K, TEF, MLSSA, and other commerically available machines in a given acoustic space with a given speaker. I suspect Andre has never seen, owned, or operated one of these devices based on my previous experiences with his writing. The "lowest frequency in a room" calculation stumping most audio engineers is an even more specious argument, because it stumps all of them! You can only estimate it, even after having all of the dimensions and materials entered into you auralization program (like EASE or Bose's). Again, you have to measure it with computer driven analytic tools to really know what's going on. The acoustic size of a room (not the mechanical size) varies with frequency. In smaller rooms (like the one you're probably in right now) you have dramatic differences in energy densities with time, which argues against the traditional homogenous, statistically reverberant sound field calculations. The acoustic juncture between of a small room can fall as high as 500 Hz, where it is typically below 30 Hz in a small room. The frequency dependency of the pressure zone, modal zone, the diffusion zone, and specular reflection zones will alter with room treatments. In other words, the low frequency cutoff changes constantly as you play your music. I suspect the same is true of your listening acuity as well, which further complicates the issue. |
The damping factor and the sound of real music
Andre Jute wrote: Hey, Jim, this is my thread Usenet is public not private. It's NOT 'your thread'. Graham |
The damping factor and the sound of real music
In article
, Andre Jute wrote: I've oft wondered about that. My actual experience of electrostatics is limited in depth to the original Quad design. And those had perhaps the most critical sweet spot of any speaker, but when in it had excellent imaging. I never did have an opportunity to live with a stacked set up to really decide how well it worked. Well, I had stacked ESL57 for years, and perhaps everyone should experience them once but stacks are not the end-all and be-all of stats; I'm just explaining to Poopie how it is done with the round- form diaphraghms like the ESL-63 because he doesn't appear to have the brains to work it out. The 57 is tricky to stack right; you can as easily muddle your sound as boost its volume. You stack ESL-57 one on top of the other, the top one turned upside down and angled towards the bottom one, the entire assembly pivoted around the joint towards the listening chair, ditto for the assembly on the other side. Each assembly is also angled inwards in relation to the side wall to face the listening chair squarely (line from the listening chair to the radiating face hits it perpendicularly). Now you're looking at four imaginary lines making a pyramid towards the listening chair. It helps to get the four lines the same length if you raise the assembly on each side several feet and tilt it over towards the listening chair. As by now you suspect, stacking ESL57 turns your music into a perfectly lonely pastime; the sweet spot becomes hypercritical in three dimensions. I kept stacked ESL for years because mine was aimed at my work chair in front of my computer, in which I sat in the sweet spot for hours. Visitors to my study had only a partial experience of the music... What I suspected. I only really heard them once and was plonked in the listening chair by the owner. And was reasonably impressed - although I need long term experience to form a firm opinion. For years I also had a singleton 57 from some old chappie who read my music column; it came complete with correspondence in Peter Walker's own hand which I still have. Sometimes for months on end I would play just the single 57, and not because I was moving around, quite the contrary: I was sitting at my desk for 16 hours every day grafting away on a big book. I remember that as one of the sweetest musical experiences ever, a really good reason to go mono; that is still my reference of the purest, most angelic sound I ever heard. Soundstaging is really a rather trivial trick, and the only one stereo offers for what is often a very high price in its associated downsides; it is a party trick for "audiophiles" who have no real interest in the enjoyment of music. I totally disagree. Everything being equal good stereo adds considerably to the enjoyment of pretty well any music or indeed reproduced sounds. It is of course more difficult to get good stereo in an average room and possibly also to record it. Certainly to reproduce it on early media which had to be mono compatible. Both FM radio and LP suffered flaws through the adoption of stereo. -- *If tennis elbow is painful, imagine suffering with tennis balls * Dave Plowman London SW To e-mail, change noise into sound. |
The damping factor and the sound of real music
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The damping factor and the sound of real music
"Andre Jute" wrote snupped to isolate the point Snupped?? Whatever.... For years I also had a singleton 57 from some old chappie who read my music column; it came complete with correspondence in Peter Walker's own hand which I still have. Sometimes for months on end I would play just the single 57, and not because I was moving around, quite the contrary: I was sitting at my desk for 16 hours every day grafting away on a big book. I remember that as one of the sweetest musical experiences ever, a really good reason to go mono; that is still my reference of the purest, most angelic sound I ever heard. Hah! Soundstaging is really a rather trivial trick, and the only one stereo offers for what is often a very high price in its associated downsides; it is a party trick for "audiophiles" who have no real interest in the enjoyment of music. It never fails to amaze me: a) that so many people dismiss mono simply because it isn't stereo and b) don't know when they are listening to mono anyway!! Only last night, my visitor (presently suffering from ME and struggles to get out of the house atm and whose weekly 'Tuesday therapy' transcends trivial interruptions like Christmas) who is a good listener and good *hearer* requested Brubeck at hideous o'clock last night/early this morning. I put on the version I like best (original '59 mono recording on Fontana TFL5085) and we were listening to it; suddenly he said 'That's *mono*!' - I said 'Yes, do you like it? 'Oh yes!', sez he (Take Five - wot else?) Stereo has got a lot to answer for with some stuff - 20' wide violins and pianos being wheeled backwards and forwards across the stage and such! Here's a Christmas 'Stereo Quiz' game: Change the following in 5 moves, only one letter at a time: ENHANCED - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ****EDUP |
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