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Beyond Stereo to multiple Speakers

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David Pinnegar

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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 9:49 am

mdyde wrote:For wet stereo (as opposed to surround) sample sets, specifically from an acoustics point of view, either headphones or a single pair of high-quality near-field speakers (optionally with sub-woofer) in as dry (anechoic) listening environment as possible should give the most accurate reproduction in terms of preserving the room reflections present in the wet samples, yielding a result that should be identical (from an acoustics and speaker point of view) to listening to a CD recording of the real organ made with the microphones in the same positions used during sampling.

:shock: :shock: :wink:
:)

Best wishes

David P
http://www.organmatters.co.uk
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Organorak

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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 10:49 am

It's taken a little while to get there, but reading this thread from start to finish has I think successfully answered all the audio questions I'd been storing up. Sorry to Brett and Martin if they have spent time interjecting, but I for one am glad that these rambling threads exist from time to time, even if we need the likes of Joe to provide exceedingly helpful summaries now and again.

David P is a personal friend of mine, so I come into the debate bearing the risk of a conflict of interest. I have not heard him play Hauptwerk through his home organ, but having played it in concert I can certainly testify that it is, in the main, one of the most convincing electronic reproductions of a pipe organ, and in addition something of an organ research tool, allowing the possibility of any manner of stop combinations, temperaments and audio reproductions. He has some pretty innovative speaker designs that he can be rightly proud of designing, and I feel I've learnt a lot both from reading his posts and those of others who disagree with him. After all, most people reading this sort of thread are probably not going to be those who are after the cheapest stereo computer speakers - those for whom that will suffice might never get this far in the thread to be confused by all the advice. But he does have an enormous room for the Beast, much bigger than most Hauptwerk users can enjoy, and what is necessary for that size room would probably be overkill in many other rooms.

David owns two pipe organs in his house too and is quite clear that he does not wish electronic technologies to take over pipe organs where these are an option. I think and hope most Hauptwerk users would agree with that position.

As this thread started (I think) around questions of multiple speakers versus stereo, I would gratefully point out that since I am only planning to use wet or surround speakers, I think I've been well and truly answered - go for a decent pair of headphones or stereo speakers and don't feel the need to have multiple pairs. For those running dry sets and wondering if stereo speakers are enough, by all means invest in multiple pairs, or add reverb... So thanks David for a stimulating debate, thanks Martin and Brett for taking him to task, and thanks everyone else for the chance to examine his claims with a fine toothcomb.
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 11:48 am

And I want to thank Martin for posting the links to the YouTube info about David P’s house, Hammerwood, which led me to other videos about David’s restoring of that huge mansion. I love to watch the TV show here called “Treasures of the National Trust” which features many of those large old British homes. And, wow, there’s David actually owing one of them! What a project that has been!

Who knew??!!?

Just think, what a terrific HW multi-speaker set up could be put into such a place! Combining the versitility of HW with David's speakers designed specifically for the room might result in about the finest HW setup ever.

Leo Chris.
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 12:36 pm

crediting Clinton with the most complex installation


That depends on how you look at it. With 44 channels, mine may be the among the largest permanent public HW installations to date. But Leo Chris has a far greater number of channels running in his home. Leo's channel allocation spreadsheet continues to be an invaluable reference.

I built all of my speakers, ranging from 1.5 to 20 cubic feet, and some early input from David P changed my direction in a positive way. I evaluated a few of his suggestions objectively (i.e. with modeling and/or measurements), and not all of them panned out for my project, but I'm still very grateful for his input.
Clinton Knight
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David Pinnegar

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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 3:05 pm

Hi!

:oops:

Thanks everyone for such comments, but really . . . I'm most disappointed in all of you in support as 8) I had sworn all of you to secrecy . . . :lol:

In continuing this thread, I appreciate that I'll be severely off topic specifically but crave your indulgence just once, as it does lead to something important.

Really whilst Martin very kindly directed people to an interesting interview of the 1980s in which I explained the "how" of coming to Hammerwood, the "why" was really much more interesting. In 1982, here was a place ostensibly allowed to go to rack and ruin by a famous pop group (thank goodness or it would have had a fate even worse) and it had 14 holes in the roof that didn't exist. The estate agents could not put a photograph of it on the advert - only a sketch, with underneath words in the nature of "in need of modernisation"

"HELP HELP HELP" the place was screaming . . . and seeing it for the first time I thought that anyone who took it on would have to be stark raving mad. (No comment)

The reality after 28 years is a place that comes to life bringing people to life with creativity and especially music. In taking on the house and its restoration, which the National Trust and others felt impossible, I challenged established norms.

I should add, however, that 28 years survival at Hammerwood from times of dereliction and disasters common to all struggles, has only been achieved by reason of a sense of humour :lol: which is often incomprehensible. Apologies to anyone who might have been offended inadvertently as a result.

I'm bringing music to life both for musicians and audiences its original colour of unequal temperament, and probably the only venue hosting regular recitals where it can be heard on the piano. I was probably the first, after a late 1990s performance of Chopin's second sonata to recognise and suggest that Chopin was writing for an instrument in unequal temperament. Experimental concerts have ensued beyond Chopin to Liszt, Brahms, Debussy and Prokofiev in which we have witnessed clear empathy of the music with the temperament and otherwise with later composers no detraction suffered by its use. With Adolfo Barabino, we have proved the case for Chopin in practice, and it's interesting to see http://www.millersrus.com/dissertation/ in the same vein. Now in the USA, tuners are going back to UT as standard practice http://www.radfordpiano.com/repertoire.html . I sympathise with the article http://www.radfordpiano.com/future.html and love the comment:
I believe that Equal Temperament also plays a contributing factor in the piano's decline in popularity. . . The discovery of Well Temperament, for me, was like viewing a Picasso painting in black and white all my life, and then for the first time seeing all the reds, blues, and greens I didn't know were there. If Johnny's Steinway is tuned in color and Susie's Steinway in black and white, who do you suppose is more likely to want to continue learning to play?


The result here is that we get musicians enthusiastic to perform to audiences who want to share their passion. This is one reason why elsewhere I have encouraged musicians to advertise their concerts and with their programme explain the passion behind their choice of programme and their choice of venue and or instrument.

One of my ambitions is to work with any organists who are willing to do so, to record established organ repertoire even intended for equal temperament in unequal temperaments, and see just how far we can get to see really what would be precluded by building pipe organs as standard in UT. (By UT, I do not support the Lehman Bradley upside down interpretation of Bach's squiggle: it has no musical nor historical precedence and other solutions to the problem accord with precedents)

Why all this? Because like Hammerwood I discovered an organ in dereliction, which unlike Hammerwood I could not save from the bulldozers.

And that's the point: appreciation of the Organ as an instrument is derelict among the wider population.

In deciding to do something about this, I minded to add the Organ to the concert platform that I had been operating for a quarter century. To do so outside the normal boundaries of ecclesia would not disable anti-church people from enjoying the instrument. The ex Addington Palace Hunter was not inspirational enough to bring the King of Instruments into the necessary realms of enthusiasm. To succeed the result had to achieve the attainment of the absolute best, and this has been a continuing quest in the past years.

I was forced to do this using the technology and resources available to me, and having the pipe organ in the same room enabled exacting critical comparison as I sought better and better result from the ex Londonderry Cathedral instrument by voicing, additions, and attention to speakers.

Hauptwerk's universality is a brilliant tool, capable of being to the instrument as crucial to the organ as Gutenberg was to freedom of speech and thought from the dissemination of the printed word. It's for this reason that collectively we have the most wonderful opportunity to pull together in the cause, discovering rather than arguing, and promoting research and enthusiasm along the way. I hope that in 30 years time, we will see pipe organs appreciated, cherished and loved as a result and pipe organ builders flourishing.

In the course of this passion, it has been great to find organists with enthusiasm to share and even a pipe organ builder brave enough to add a tagline to his full page advert in Choir and Organ magazine promoting a concert here by a top and raptuously enthusiastic performer in November.

I'm trying to persuade a local organist of international stature to come to practice here at 4pm on days when the house is open to the public, and in this way, as with the position of the cinema organ in people's minds, I hope that we will inspire a more general public familiarity, understanding and enjoyment. All visiting organists are welcome in this vein.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

In view of such gracious recent comments in this thread I thought it appropriate to fill in gaps here, (apologies to anyone of contrary persuasion), and in view of those comments I hope that this posting will not impose on the leniency of the moderators and providers of this forum nor distract them from their software development nor require their further intervention.

(When they have finished and want to holiday in Sussex, my invitation is still open, but obviously not in paid time! )

However, for that reason please can I urge continuation of this thread only in the direction of any further questions or clarifications on the original topic, and any further mention of matters raised in this post be continued more appropriately elsewhere.

Best wishes

David P
http://www.organmatters.co.uk
David Pinnegar, B.Sc., A.R.C.S.
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 3:26 pm

Eeeee.... this thread probably establish a world record for its growth speed!

I read only a small part of it... stereo, multi-channel, dry, wet, beating, intermodulation, distorsion... I don't know what each and every posts said... lot of mombo-jumbo tech-talk... :roll: but in the end, as I often say, * your ears will guide you *

What I sometimes do as a demo when explaning "multi-channel" is to play Hauptwerk with 2 channels, then adds more channels, (4,6,8, rear speakers)... and each an every time the ears of the "clients" are saying... the more speakers, the better! Maybe it is because of my music room acoustic, maybe it is because of the voicing I did and way I placed my speakers, maybe it is because of the brand of speakers, kind of cable or color of the paint on the wall... who knows... :wink:

In the end, *YOU* will decide... why not buy 2 good monitor speakers (don't go over the top...though) then try to borrow 2 or 4 other speakers from the store for a test at home... you will see for yourself then if it is worth it for you ... forget everything you read and let your ears decide.

The important thing in the end is that *YOU* like the sound and enjoy your Hauptwerk system.

Sorry, if I didn't read the entire thread, sorry if I'm off topic or I'm repeating what was written already by someone else... but I've been busy *enjoying my Hauptwerk system" :D the way it is set up, the way I like it.

Enjoy and trust yourself, trust your ears!

François
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 4:57 pm

Hi François,

micdev wrote:What I sometimes do as a demo when explaning "multi-channel" is to play Hauptwerk with 2 channels, then adds more channels, (4,6,8, rear speakers)... and each an every time the ears of the "clients" are saying... the more speakers, the better! Maybe it is because of my music room acoustic, maybe it is because of the voicing I did and way I placed my speakers, maybe it is because of the brand of speakers, kind of cable or color of the paint on the wall... who knows... :wink:


Out of interest, is this with wet or dry sample sets?

micdev wrote:In the end, *YOU* will decide... why not buy 2 good monitor speakers (don't go over the top...though) then try to borrow 2 or 4 other speakers from the store for a test at home... you will see for yourself then if it is worth it for you ... forget everything you read and let your ears decide.

The important thing in the end is that *YOU* like the sound and enjoy your Hauptwerk system.


I agree, but I think the issue that many potential HW users have is being able to design and cost a system prior to taking the plunge without being able to visit a HW showrooms to explore different configurations and understand the relative cost/benefits. Your suggestion about starting small and perhaps growing sounds great, but (as you well know) studio monitors can be many 100s if not 1000s dollars/pounds/euros, not to mention the additional cost of swapping from a two channel to a multi channel sound card etc. The audio system has the most scope for variation and expense within a HW setup, I think it is because of this that there is a lot of uncertainty in which direction to go. I found Joe's FAQ posted early on in the thread extremely useful (thanks Joe).

James
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 5:35 pm

Hello James,

I demo both types of sets, wet and dry (with added convolution). As I wrote, to my ears (and to other people ears), I prefer the sound coming from many speakers. From two speakers, I find that there is a lack of "width and depth"... play a few stops and it is nice... play a tutti and "to my ears", there is something wrong.

Now, as far as monitor speakers goes, you can get monitor speakers from $200 to more than $2000! Mackie, M-Audio and Rokit speakers at between $400-$600 a pair do a great job. If I do an A/B comparison between $500 and $1500 monitors.. sure I will hear the difference, but 10x$1500 monitors is probably "overkill"!

When using my Hauptwerk system with 10 front speakers (M-Audio Bx5a) and two rear ones (total cost less than $2000 excluding the sub) compare to my JM-Labs stereo speakers ($4000/pair), it is a totally different world... go figure. More presence, wider sound, less "confusion" as I add more stops. Of course listening to a cd on 2 Bx5a is no match compare to my JmLabs!

A multi-speakers/channel system will also give you a more "full sound" at low level (especially nice if you don't wan to bother to much your wife :lol: or neighbour).

I also understand that people don't want ot change their sound card, but a good 6-8 outputs card doesn't cost a lot more than a good 2 out card... and even if you plan to use only 2 channels, you may be interested to eventually add 2 rear speakers (well worth it!). Also some cards can be chained; so you can buy a 4 outputss and should you need more outputs, chain another 4, 8 or 12 (presonus and echo to name a few).

This way you don't have to over-invest and have possibilites to expand... then become friendly with your Hi-Fi store saleman and borrow some additional speakers to see if it is worth it! :lol:

One of the beauty of Hauptwerk is its modularity, allowing you to have your system grow as your $$$ becomes available :shock: ... start with a chapel system... finish with a cathedral :mrgreen:

Regards
François
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Virtually sharing my enthusiasm and experience with you
Worldwide technical assistance, consultation and ready to play system.

http://www.HauptwerkConsultant.com

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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 6:05 pm

jwillans wrote:I agree, but I think the issue that many potential HW users have is being able to design and cost a system prior to taking the plunge without being able to visit a HW showrooms to explore different configurations and understand the relative cost/benefits. Your suggestion about starting small and perhaps growing sounds great, but (as you well know) studio monitors can be many 100s if not 1000s dollars/pounds/euros, not to mention the additional cost of swapping from a two channel to a multi channel sound card etc. The audio system has the most scope for variation and expense within a HW setup, I think it is because of this that there is a lot of uncertainty in which direction to go. I found Joe's FAQ posted early on in the thread extremely useful (thanks Joe).

François and James,

You both exhibit a lot of common sense, and thank you for staying on topic. Just a couple more thoughts... relative to the cost of one of the big name digital organs, Hauptwerk and associated peripherals can be considered a real bargain. When planning expenditures, speakers (easily the weakest link in the chain) deserve a prominent position in the decision tree. It would seem wrong headed to me to spend several thousand on a Mac Pro with 32 GB and only a few hundred on speakers. I agree with James' comment that it may be wise to start out small with two very good speakers and subwoofer. One can add on as budget and other considerations permit.

From a purely financial point of view, I look at my investment in used Mackie HR824 monitors as money in the bank. I will always be able to resell them at the same or higher price.

Joe
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 6:08 pm

jwillans wrote: but (as you well know) studio monitors can be many 100s if not 1000s dollars/pounds/euros,


Hi!

In thinking "outside the box" I often say that if one thinks of hi-fi, one will get hi-fi. When I heard the doyen of popular organ concerts playing a commercial brand in Sussex a few years ago, I'd rather have listened to my own hi-fi at home: he might have been at an organ console but the reality was that of hi-fi rather than an organ. This did no credit to the instrument.

Before buying a studio monitor, I suggest recording a cymbal - microphone probably a foot away from the cymbal, or obtaining such a recording. I may try to obtain one and post a link to it from here.

If you play that recording back through the studio monitor and you can almost "see" the cymbal at the speaker, then that speaker is gold-dust. In the hi-fi showroom, take a violin or cello concerto recording, and one should be able almost to "see" the bow in contact with the string and the bridge upon the soundboard. If a speaker meets that realism, it will be good for most organ music - and if not, the test can save a lot of money.

Best wishes

David P
http://www.organmatters.co.uk
David Pinnegar, B.Sc., A.R.C.S.
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 7:34 pm

It would seem wrong headed to me to spend several thousand on a Mac Pro with 32 GB and only a few hundred on speakers.


Joe,

First of all I wouldn't spend *several thousand on a Mac*, but rather a *few thousand* only on a PC (sorry couldn't resist :wink: ). And agree that buying only 2 x $200 monitors speaker won't do justice to Hauptwerk... the question remains... should I buy 2 speakers for $2500... or many for the same price?... For me, it is "many"! (Hey, you're the one who taught me that a few years ago)

My best regards
François
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Virtually sharing my enthusiasm and experience with you
Worldwide technical assistance, consultation and ready to play system.

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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 7:42 pm

Per Martin's suggestion, I have recorded a brief demonstration of Intermodulation Distortion. In the following mp3 clip you will hear spurious non-harmonically related tones that are generated when certain intervals are played. I find these effects extremely objectionable and this, along with "signal mixing" effects, is why I advocate multiple channels for virtual organs. The audio chain for this demonstration is an M-Audio 1010LT audio card feeding an Adcom amplifier which drives a pair of B&W DM602 S3 speakers. The recording was made with a Zoom H4n.

https://sites.google.com/site/vtheatreorgan/Home/music/IM_Demonstration.mp3

Joe Hardy
Paramount Organ Works
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Re: Beyond Stereo to multiple Speakers

PostThu Sep 30, 2010 7:51 pm

I also find I prefer multi channel audio for the same reasons as Francois using wet samples.

I was originally going to just purchase a stereo sound card but then decided to get a 12 channel one instead. I'm sure glad I did, and put the money toward that, that I would have spent on the stereo one.

Also as Joe said, if I wanted to sell the 2nd hand HR824's again that I got, I would not loose any money.

Eric
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Re: Beyond Stereo to multiple Speakers

PostFri Oct 01, 2010 6:37 am

Hi!

Further to my email on assessing speakers, an important additional test is voices - it doesn't matter about sibilance, especially from FM radio, but what is important is as to whether the consonants and gutteral syllables are disembodied from the tonality of the voice. Men's speaking voices are always often difficult, especially from radio, but opera should sound natural.

With regard to the cymbal, violin and cello tests, possibly a sax, ask yourself whether this is a reproduction of a sound or the sound itself. Is it the real thing? If you can't "see" the instrument there, then an organ won't sound real. After test with one speaker, test the stereo pair and see if the image of the sound is strung in mid air identifiably between the two speakers. If a violin concerto, walk towards the speakers and through the line between and see if you feel as though you are walking through the violin.

Many modern commercial design hi-fi speakers and studio monitors don't achieve these effects, despite their price.

If speakers, whether commercial or otherwise and whether cheap or pricey, pass these tests on normal programme material, then they'll present the best of organ reality too.

Best wishes

David P
http://www.organmatters.co.uk
David Pinnegar, B.Sc., A.R.C.S.
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Re: Beyond Stereo to multiple Speakers

PostFri Oct 01, 2010 6:49 am

Hello Joe,

Per Martin's suggestion, I have recorded a brief demonstration of Intermodulation Distortion. In the following mp3 clip you will hear spurious non-harmonically related tones that are generated when certain intervals are played. I find these effects extremely objectionable and this, along with "signal mixing" effects, is why I advocate multiple channels for virtual organs. The audio chain for this demonstration is an M-Audio 1010LT audio card feeding an Adcom amplifier which drives a pair of B&W DM602 S3 speakers. The recording was made with a Zoom H4n.

https://sites.google.com/site/vtheatreo ... ration.mp3


Are you absolutely certain that you aren't yourself just confusing intermodulation distortion with perceived dissonance between harmonics whose frequencies are very close together because of the temperament and note interval?

After listening to the sections of your demo where you play one note (C) then another (E or D#) then both notes together (e.g. C and E), I don't think I notice any new frequencies being introduced, i.e. I don't think I can hear noticeable intermodulation distortion.

I can certainly hear some frequencies that clash very unpleasantly, as would be expected because of the intervals and temperament, which the brain would probably find much less noticeable/unpleasant (although still present in reality) if multi-channel audio were used.

To verify, I took these excerpts from your recording:

Tuba horn C note:
http://downloads.hauptwerk.com/forum_temp_images/Topic007379/TubaHornCNoteExcerpt.wav

Tuba horn E note:
http://downloads.hauptwerk.com/forum_temp_images/Topic007379/TubaHornENoteExcerpt.wav

Tuba horn C and E notes together:
http://downloads.hauptwerk.com/forum_temp_images/Topic007379/TubaHornCAndENotesExcerpt.wav

They were taken from around 43 - 51 seconds into your demo.

I then used Sound Forge to perform an FFT of each, i.e. to show the frequencies and their amplitudes present in each, and lined up the left channels as carefully as I could on the screen in the same order as the excerpts above (i.e. C, E, C+E):

Spectrum analysis of C, E and C+E tuba horn notes overlaid (click the link for the full-sized image):
http://downloads.hauptwerk.com/forum_temp_images/Topic007379/TubaHornCAndENotesExcerptOverlaid.jpg

Image

In the bottom section (C+E) I highlighted in red the frequencies that appear to be due to IMD (i.e. that are frequencies that weren't present in either of the C or E recordings). I also highlighted in yellow those frequencies that are not due to IMD, but are very close to each other, and so would probably sound unpleasantly dissonant because of the temperament and note interval.

The strongest three IMD peaks (the first two red circles) are only about -45 dB compared to the amplitudes of the fundamentals and neighbouring harmonics. I'd say that should be only just noticeable, i.e. you would probably only hear those frequencies if you listened hard for them - I certainly wouldn't think they would be obviously objectionable?

The dissonances (yellow circles) however, would be perceived as very noticeable and unpleasant, and they're what my ear finds significant. That effect isn't due to IMD or any shortcoming of the speaker or amplifier - that's just a result of the temperament and interval.

Edit: P.S. I had a quick look for the specifications for the Bowes & Wilkins speakers you used, but couldn't find very much detail (particularly the manufacturer's IMD (SMTP) figure):

http://www.bowers-wilkins.com/display.aspx?infid=1424&searchtext=%27602%20s3%27&swp=0&spdf=1
http://assets.bowers-wilkins.com/med/Libraries/3/602S3_l2_w0_h0.pdf

For the Mackie Mackie HR824MK2s, the manufacturer's IMD (SMTP) figure was about -69 dB (which is measured relative to the amplitude of the signal):

http://forum.hauptwerk.com/viewtopic.php?f=17&t=6927&p=48755#p48755

The very approximate -45 dB IMD peaks measured from your demo are higher (maybe your B&W speakers aren't quite as linear as the Mackies, also it's a very crude measurement on my part) but they're within a similar ball-park, as a sanity check.
Best regards, Martin.
Hauptwerk software designer/developer, Milan Digital Audio.
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