This, https://www.youtube.com/watch?v=3Wpn7xyzUqg, is what a lot of people seem to fantasise about - trouble is, most musical instruments are designed to produce music, rather than show off ... shame about that ... 
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Well, you are looking at the data sheet, picking some numbers, ignoring others, and drawing bad conclusions. The info is there in the data sheets for you, if you read all of them.
You pointed to these two carts as indicative of a gross mis-match, but where's the analysis? As somebody else pointed out, in a SME 309 arm, which has an effective mass of 9.5g, the Ortofon would have a resonant frequency of 9Hz. The Lyra, even if we use the lower 12x10-6cm/dyne compliance number, with its higher mass it would have a resonant frequency of 11Hz, not a huge difference. However that compliance is @100Hz, which is commonly done by many Japanese manufacturers (AT, and my Denon MC), and they generally have a higher dynamic compliance in the infrasonic region, usually by a factor of 1.2 to 1.5. No, I don't have a citation or measurements for that, but that is "audio folklore". So if the Lyra has an actual compliance more like 18, then in that same tonearm it has a resonant frequency of... 9Hz. If the real compliance is more like 15, the resonant frequency goes up to 10Hz. Pretty much a wash.
I do wonder whether some MC cartridges have a little better damping than typical MM/MI cartridges. I remember selling a system to a young man who had his heart set on a Grace F9-E cartridge, even though he was buying a relatively inexpensive TT (a Rotel). When I mounted the cartridge in the tonearm and played a record with a small warp, the woofers were dancing the mambo. I asked him to let me try something, and swapped in an Ortofon MC-10 (the integrated amp he was buying had a MC phono stage), and the woofers stopped flapping. On paper there should not have been much difference between them, though I wonder about the Grace compliance spec (maybe they also used the 100Hz measurement).
If you do want to show off on an organ, this is the way to do it - https://www.youtube.com/watch?v=hHZvMAJUN5g ...
Dear Richard Marsh,
Maybe a solution is around the corner.
Binaural+ Series | Chesky Records
I'd give these recordings a try and see
what you think.
Kindhornman has a valid point though.
Also what is the length of the room the
subs are in?
Sitting near field more woofers might not be what you need.
you have have to fool with some 8 x 8 Ampeg
type or 4 x 10 bass cabs.
The 4 x 10s are what a lot of the bass cats use on stage.
Someone pointed out that that the big woofer form in the Acoustic cab
wouldn't give you what you need to hear on stage.
OR
YOU might have to get one of the Wilson subs and
tune it. The work from what I'm told, but once the
servo goes out, your screwed and can't re tune them
any longer. I don't remember what the part was
but it's unobtainium.
A few (maybe more) years ago they re recorded the sonics
of the JFK assassination. At that time I thought they should
have done the binaural series at various locations around
the site. Then had the people in attendance on the grassy knoll
identify if what is recorded what they heard.
They could have gone back through the two other locations where they
say the other gunman was located.
Too many people on the knoll including the Govenor Connely
and avid hunter and shooter, said there was another shooter on
the Grassy Knoll. They should do this before all the ear witnesses are gone.
Maybe a solution is around the corner.
Binaural+ Series | Chesky Records
I'd give these recordings a try and see
what you think.
Kindhornman has a valid point though.
Also what is the length of the room the
subs are in?
Sitting near field more woofers might not be what you need.
you have have to fool with some 8 x 8 Ampeg
type or 4 x 10 bass cabs.
The 4 x 10s are what a lot of the bass cats use on stage.
Someone pointed out that that the big woofer form in the Acoustic cab
wouldn't give you what you need to hear on stage.
OR
YOU might have to get one of the Wilson subs and
tune it. The work from what I'm told, but once the
servo goes out, your screwed and can't re tune them
any longer. I don't remember what the part was
but it's unobtainium.
A few (maybe more) years ago they re recorded the sonics
of the JFK assassination. At that time I thought they should
have done the binaural series at various locations around
the site. Then had the people in attendance on the grassy knoll
identify if what is recorded what they heard.
They could have gone back through the two other locations where they
say the other gunman was located.
Too many people on the knoll including the Govenor Connely
and avid hunter and shooter, said there was another shooter on
the Grassy Knoll. They should do this before all the ear witnesses are gone.
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Even if it is not a very big room---a concert hall for example---you can use carefully-placed multiple subs, and compensate for room gain, and make the coverage almost uniform. We hear this so infrequently that it's difficult to get used to when it has been done. Well, at least it has been for me. I don't know offhand the various GD parameters realized, but things sounded very good.
Sadly, most listen for slightly-exaggerated bass I think. Biased here, because of working for so long with systems that were always to some degree bass-deficient.
Sadly, most listen for slightly-exaggerated bass I think. Biased here, because of working for so long with systems that were always to some degree bass-deficient.
This, https://www.youtube.com/watch?v=3Wpn7xyzUqg, is what a lot of people seem to fantasise about - trouble is, most musical instruments are designed to produce music, rather than show off ... shame about that ...
Then there is this monster -https://www.youtube.com/watch?v=Zscqshch6N4
LA - worlds largest. I have a flac of this , lot of notes I can see DSP and
feel port "wind" Can't hear. I suppose that gets em' feelin' "religious".
OS
+1
The group delai linearity of a speaker is, on my point of view, only important in the upper octaves after 1KHz. Where we use phase localization. And anyway not achievable under-it in practice.
Here an example of a perfectly aligned enclosure (in the axis).
http://www.moonaudio.fr/Photos taille affichage/group delay.jpg
About Organs, i always wondered how somebody can play this instrument. The distance is so high between the keyboord and the pipe that the sound comes to the ears of the player with a huge delay. (And the keys are not sensitive). My mother was a pianist, and sometimes asked to play organ for ceremonies. She hated-it and used to say: "Hard to play on such an elephant when what you hear is somebody else playing your instrument after-you" ;-)
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My speakers use a 7 degree slant of the front baffle from down upwards and should be time aligned at about 3 m (9 ft). Therefore, like in all other cases, it is simply an approximation, good at 3 m, but at less or more, it's off axis.
I honestly don't know whether that also plays a significant role in their clarity and coherence, whether it helps the box to sonically disaapear, my friend's and my feeling was, well, we did everything by the book, so why not this as well.
As for deep bass, we used what I think I remember was Son Audax' best bass driver at the time. We knew we couldn't get it down to its Fr at 29 Hz, not at the size we wanted, so we settled for maximum linarity up to where it could go, which is effectively 40 Hz, even if the port is tuned to 36 Hz. In other words, it will not do the first octave, 20-40 Hz, very wll, for that I'd need a bigger driver and a bigger enclosure, which was a no-no.
The other reason why we never went for lower still was the rooms which it would be in. Local apartments use small room, so we figured the room cut-off would be above what the speaker was capable of. My room is 4 by 3.5 m (app. 12 by 10.5 ft) net area (i.e. effective free space) and for that size of a room, I have yet to hear a cleaner and more exciting "bookshelf" speaker. By the time the tympani kicks in, the response is already within +/- 1.5 dB tolerance, and the sound is impressive. Since they do 92 dB/2.83V/1 m, peak power required is still pretty low with no audible strain on either the Marantz amp (nominally 85WRMS/8) or the H/K (nominally 170W/8).
In short, thunder comes across as thunder, as no fashionable small speaker could ever hope to do. And low frequencies can easily drive the music along, practically all 2nd harmonic low sound is catered for.
I suggest more attention is paid to the whole rather than bits and pieces, including time alignement. For the curious with cash to spare, one can find the original B&W DM6 ("The Fat Man") time aligned system which started it all in the late 70ies, they still sound damn good even today.
I honestly don't know whether that also plays a significant role in their clarity and coherence, whether it helps the box to sonically disaapear, my friend's and my feeling was, well, we did everything by the book, so why not this as well.
As for deep bass, we used what I think I remember was Son Audax' best bass driver at the time. We knew we couldn't get it down to its Fr at 29 Hz, not at the size we wanted, so we settled for maximum linarity up to where it could go, which is effectively 40 Hz, even if the port is tuned to 36 Hz. In other words, it will not do the first octave, 20-40 Hz, very wll, for that I'd need a bigger driver and a bigger enclosure, which was a no-no.
The other reason why we never went for lower still was the rooms which it would be in. Local apartments use small room, so we figured the room cut-off would be above what the speaker was capable of. My room is 4 by 3.5 m (app. 12 by 10.5 ft) net area (i.e. effective free space) and for that size of a room, I have yet to hear a cleaner and more exciting "bookshelf" speaker. By the time the tympani kicks in, the response is already within +/- 1.5 dB tolerance, and the sound is impressive. Since they do 92 dB/2.83V/1 m, peak power required is still pretty low with no audible strain on either the Marantz amp (nominally 85WRMS/8) or the H/K (nominally 170W/8).
In short, thunder comes across as thunder, as no fashionable small speaker could ever hope to do. And low frequencies can easily drive the music along, practically all 2nd harmonic low sound is catered for.
I suggest more attention is paid to the whole rather than bits and pieces, including time alignement. For the curious with cash to spare, one can find the original B&W DM6 ("The Fat Man") time aligned system which started it all in the late 70ies, they still sound damn good even today.
Here's a decent article about group delay, and its proper meaning, also setting out how it can be normal and natural to have negative values and what that physically means in context.
Time Machine, Anyone? - Andor Bariska
Time Machine, Anyone? - Andor Bariska
If the crossover frequencies are kept low enough, and the filterslopes steep enough, the physical distance between the drivers can lead to a large major lobe that provides a wide listening area where the FR is sufficiently flat.
With very high filter slopes, there is virtually no lobing.
It is impossible to realize minimum phase filters with such high slopes, without running into audible artifacts connected to phase shift. Therefore, FIR filtering is the way to do it if you really think there is a problem. Philips did some prototypes in the middle nineties which where actually very good (but impossible to market at the price they needed for them).
This failure also came about because there isn't a real problem. With a 4th order LR and decent drivers, you can get a vertical listening window of around +/- 20 degrees. Large enough. It can even be argued that some amount of vertical lobing is not a bad thing, because it can limit floor and ceiling bounce. Horizontal dispersion is limited by driver geometry in combination with xover point, no lobing or time align problems here.
That is not how Organs sound in cathedrals. If you are after 'high fidelity' then throbbing and trembling are certainly not on the list of desirable outcomes.
I was attempting to convey the sense of the sound, the house certainly doesn't have to literally tremble. Too often, reproduction does not convey the emotional impact that one experiences in the presence of live instruments, and the latter for me is a strong motivation to optimise playback.
The reproduction of an instrument can sound "better" than in real life, because the recording environment is typically optimised for the task at end: microphones are carefully placed in the very best position to pick up nuances, takes are done until the 'perfect' version has been captured, subtle enhancing is done to bring out some quality in the instrument; live, you get the seat you get, with audience noise, and the performer perhaps not quite on top of his form - you takes your chances. Personally, I was startled a couple of decades ago going to a piano recital, in just OK seats, and thinking during it, this just does not measure up - if I had been sitting on the stage, a few feet from the performer, then my opinion would have been quite different.
On group delay: it's a red herring, but a complicated one, so if you have made the effort to understand what group delay is, it might be hard to disregard it as a useless measure.
Here is why. The auditory system is logarithmic, both in level and pitch. It is about the latter, pitch. Group delay goes wrong because it is a linear measure; it treats 1 delta Hz at 40 Hz the same as 1 delta 1 Hz at 4000 Hz. The consequence is that the GD figure gets very large at the low end, and very small at the high end, even if we talk about the same level of phase shift per octave.
And this is what the relevant measure should be, psyco-acoustically: the amount of phase shift per octave. Replace the delta Hz in the GD formula with delta log(Hz) and you might wind up with something more useful.
Here is why. The auditory system is logarithmic, both in level and pitch. It is about the latter, pitch. Group delay goes wrong because it is a linear measure; it treats 1 delta Hz at 40 Hz the same as 1 delta 1 Hz at 4000 Hz. The consequence is that the GD figure gets very large at the low end, and very small at the high end, even if we talk about the same level of phase shift per octave.
And this is what the relevant measure should be, psyco-acoustically: the amount of phase shift per octave. Replace the delta Hz in the GD formula with delta log(Hz) and you might wind up with something more useful.
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Augmented reality, not Hi-Fi IMO.
Frank you seem to not enjoy much with music!!!!! I'd would enjoy the experience and music, whether my seat was optimal or not, been to many a gig where it was not as clear as the CD (or LP) due to loads of other sweaty bouncing fans that had the audacity to come to the same concert and interfere with the sound reproduction, cheering, bouncing about and generally enjoying themselves... Audiences
Frank you seem to not enjoy much with music!!!!! I'd would enjoy the experience and music, whether my seat was optimal or not, been to many a gig where it was not as clear as the CD (or LP) due to loads of other sweaty bouncing fans that had the audacity to come to the same concert and interfere with the sound reproduction, cheering, bouncing about and generally enjoying themselves... Audiences
It seems all-pass filters have their own problems
http://www.conforg.fr/acoustics2008/cdrom/data/fa2002-sevilla/forumacusticum/archivos/psy03001.pdf
https://www.pa.msu.edu/acoustics/allpass.pdf
http://www.cs.ust.hk/mjg_lib/bibs/DPSu/DPSu.Files/Ga95.PDF
Bill Gardner's projects page
Scott, see the freq spectrum.
My AKG K240 can’t do it.
PIPE ORGANS: Organ Notre Dame Paris
By time aligning two drivers we try to avoid the time step change between the two units (*). With perfectly aligned drive units and excluding the cross-over implications (say, reaching the case of a single full range unit), the phase does slope across the band and it’s not very linear, consequently phase delay is not constant.
(*)They say that this time step change becomes acoustically significant when it is more than ¼ the period of the signal. For subwoofers crossing low at 40Hz this time step is approached at spatial displacement difference of ~2.2m between sub/listener and woofer/listener. I’ve experimented with up to double that distance but I can not hear a bad effect
Compared to most of musical instruments delicacy (play and sound), the organ is an elephant.
George Balanchine once, asked Igor Stravinsky if he could compose the music for a ballet to be danced by elephants.
Stravinsky only asked : Elephants of what age? He got the answer: Young!
He wrote it. ‘Circus Polka: For a Young Elephant’ (for fifty elephants and fifty ballerinas)
George
Attachments
Concert promoters would love to see you in the audience, marce - always the happy customer!I'd would enjoy the experience and music, whether my seat was optimal or not, been to many a gig where it was not as clear as the CD (or LP) due to loads of other sweaty bouncing fans that had the audacity to come to the same concert and interfere with the sound reproduction, cheering, bouncing about and generally enjoying themselves... Audiences
In fact, I have some pretty lousy experiences at shows with sound reinforcement in poor shape; when done well it makes for a memorable time, and when off it becomes excrutiating, a dentist's chair episode - I'm paying good money for this crap ... ?!!!
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