Single wave file for voice storage versus one per note.

[HOW]

In a pipe organ, most builders use flue pipes for the upper octave when building a reed rank. So when sampling a pipe organ for use in a virtual organ it makes sense to sample each note to achieve the "exact" duplicate of the original voicing. However, it is conceivable to build an organ with the reed scaling from note 1 to note 61 without the use of flue pipes. In this case it would seem that a single recording can be used for all 61 notes. The pipe organ is one of the few instruments that has the harmonic (partial) structure that does not necessarily change from C1 to C6. Some high frequency attenuation may be in order though. The older digital Allen Organs use a single sample as do others. I can play 1971 vintage Allen Organ voices (32 words X 8 bit) using Hlabs TWGs and cannot tell the difference between many modern virtual organ voices except for the articulation (attack and release) which is irrelevant when playing ensembles. Other instruments such as orchestral and the like have a variable harmonic structure such that the high notes have different harmonic content than the low notes that are rich in harmonics. In this case all notes must be sampled. All comments welcome.

[Analogicus]

HOW,

It's just not true that across a pipe rank the harmonic structure does not vary much, or if there is some variation, it can be taken care of with some judicious low-pass filtering towards the top of the range. In fact, harmonic structure varies from note to note, and it is this "random" variation which is one of the reasons a rank of pipes can be so attractive. I have spent countless hours making up samples for jOrgan designs, all based on recorded sources. Because of the time involved, I adopt the compromise of one sample to two adjacent notes (it halves the time to make up a rank of samples). But I can assure you that the more samples you use, the better the result - at least for players and listeners who pay a lot of attention to the actual sound. Blandness does not contribute to musicality.

Analogicus

[sesquialtera]

Sorry, posted by mistake.

[HOW]

Hello Analogicus,
Thank you for your comment. I am confused, if the harmonic content changes from note to note, then I guess a Spanish Trumpet rank could have C1 sounding like a Bassoon, note F3 an Oboe, or perhaps another note or groups of notes sounding like a Trombone. Ideally, shouldn't each note of a properly constructed rank sound like that particular rank should sound. Now, when the air causes a pipe to speak, there are variations in the timing or phase of the fundamental which in turn affects the phase of the partials or harmonics which produces the multitude of pleasing "traveling waves". A function generator with the same audio harmonic structure would have a dead sound (bland as you accurately state) unless it would be frequency modulated very slightly and slowly. But that has nothing to do with the harmonic structure other than the phase variation(s).
My intent with this thread was to perhaps be made aware of something missing from my understanding of pipe scaling. However, your comment perhaps answers my quest regarding this subject: An audiophile has certain things that tickle his or her particular fancy and many times has little to do with pure sound. For example a particular audiophile may insist that the amplifier distortion must be under .001% yet all speakers exhibit at least 1% and more like 3% is the norm. He or she may also insist that the system frequency response (related to individual pipe organ harmonic voicing also) must be flat from 5 hz to 30k hz yet the listening area varies up to and exceeding +/- 30 db from one note to the next (except when using good headphones). In this case each individual pipe could perhaps have the fundamental and harmonics voiced to somewhat flatten this listening area. However, the fundamental may need more attenuation or gain than a particular harmonic so it would be much simpler to voice all the same (if an electronic sound generator) and use graphic equalization to correct the room response. This is the problem with the method used by most electronic organ builders including the very fine Allen Organs - Sorry Mr. Markowitz.
I have been comparing the sound of the various wave files representing individual pipes from the same rank in both the Budapest Cathedral organs (Post Instruments that are supposed to be the best) and some of the GrandOrgue samples and I must say that for my tastes, some of the GrandOrgue samples have out of character buzzes etc (fault of the pipe voicing not the recording) while the M. Post recordings have the natural cathedral reflections resulting in resonances (fault of the pipe voicing and acoustics) that for my tastes should be equalized using a 1/12th octave graphic equalizer (does not yet exist?) or better yet a parametric EQ.
That said, I guess these unintended pipe variations (I say unintended since the original builder did the best he could with what he had to work with.) are perhaps desired by true pipe organ lovers. But, do you you agree that all the pipes of a Spanish Trumpet for example should sound like a Spanish Trumpet?

[Analogicus]

HOW,
It is a matter of degree, just how much variation there is from note to note, and I hope this answers your closing question. You realise I am not talking about audiophiles in my post - I'm talking about musicians, for whom the sound as well as the music is a matter of personal concentration and leads to delight, hopefully. I'm not talking about people who are only half-listening.
I agree with what you say about distortion figures, and I would take the matter further: The human ear itself adds a level of what I would call "intermodulation distortion" - namely resultant sounds which we hear but are not actually present in the air. It seems some people claim they can't hear them (e.g. Colin Pykett in the latest article on his excellent website, an article which dismayed me somewhat, as I don't think it's up to his usual high standard). I can assure you that I can hear them, and so can those organ builders who provide pedal stops that depend on the existence of this hearing phenomenon.
I also agree on the effect of the listening space acoustics. There are so many variables, that to go to almost endless effort to reproduce exactly the sound of some pipe organ is almost pointless the moment one releases the sounds into some quite different acoustic environment. In the case of the computer organs I design for jOrgan, I hope that discerning users will take the trouble to use a soundfont editor to adjust individual notes to their own listening room! After all, I have carefully adjusted the levels across individual stops in my own listening room, using such an editor, so inevitably that has stamped its irregularities upon the results.
One other point that needs to be made is that hearers vary in what sort of sound they want to hear. Do they want to hear the sound of a pipe organ "up close" (which is my normal preference), or do they want the quite different effect which one experiences in a very large acoustic space, and listening quite some distance from the instrument? In the first case you will expect to hear the buzzes and other discrepancies; in the second the sound will be more bland, but probably more grand and even mysterious. Hearers' expectations vary enormously.
Analogicus

[L.Palo]

Hi!

Voicing is an art. (Organbuilding is as much art as a handicraft) And in all kinds of art there are different opinions of what is good. Some like it done in a certain way and others in another. It also depends very much on the style. Some call it taste... (some say that others taste is tasteless)

To be frank, there are no single correct way. There are a multitude of choices to make. Many roads to take to achieve the goal. An artwork!

In general, a sound that would be perfectly equal across all the compass of an instrument would very likely be boring to the ear. It's the variation, small but essential that enrichens the sound. It's the thing that makes it alive.

For polyphonic music especially it's essential that every sound from each pipe is to a certain degree unique (not only in frequency). Then again it's always been a goal to not have one pipe in a stop totally different in character from the next. It's the balancing act that makes it an art and the organ (or any real instrument) an artwork.

More romantic, homophonic music generally thrive with a more uniform sound. Singers would talk about equalization, or maybe egalisation. But remember that that was not always the ideal. Or still isn't for some!

Wheter we like or not, every recording is an interpretation of the actual sound. It's colored in some way, it's never exactly the same as the real sound that was recorded. If you talk with a good recording (sound) engineer you'll soon hear those words. That's also what makes recording an art, not purely science.

For me, there's absolutely no question that the newer sampled sounds from real organs available today are vastly superior in "realness" to the older tone generated electronic organs. It's so funny hearing the sound of a Principal or Flute or Trumpet of the pure electronic organs of old, when one is accustomed to the real wind of a singing pipe, flute or reed. It's just so... not real, for lack of better words.

Then again, great music can be performed even on bad instruments... But it's never the same as when the instrument in itself is a masterpiece of art in a true artists hands.

Just my opinion.

Kind regards

Lars P

[HOW]

Hello Analogicus,
Thank you for your excellent responses. You are also correct regarding the mixing of multiple frequencies in the ear, brain, soul or whatever since any two frequencies have resultants in summation and subtraction not to mention the harmonics. Too many resultants I suppose could result in pink noise.
Best regards,
Stan

[HOW]

Hello Lars,
Thank you for your comments. I remember one time an a friend said," You've got to hear this great song." Well, I thought it stunk. My brother used to say, good thing all these guys like the homely women so more good lookers are left for us. Beauty is in the eye of the beholder and so is most anything that our senses perceive. I should have expected that this thread would turn philosophical. I am developing a hardware organ/ orchestral sound generator because I weary of computer booting issues etc and I feel there is a market for such an item (if priced right) albeit a very limited market. I think that if a good sample of each voice or stop is taken, for our market, that playing a single file at the appropriate address sampling rate (and some electronic processing trickery) will be more than adequate. But the proof is in buyer feedback.
Best regards,
Stan

[L.Palo]

Hi!

Well, they say anything can be selled with the right marketing and advertising...

All the best with your project!

Kind regards

Lars P

[HOW]

Thank you Lars!
Best regards,
Stan

[twanguitar]

@Analogicus. You said:

"The human ear itself adds a level of what I would call "intermodulation distortion" - namely resultant sounds which we hear but are not actually present in the air. It seems some people claim they can't hear them (e.g. Colin Pykett in the latest article on his excellent website, an article which dismayed me somewhat, as I don't think it's up to his usual high standard). I can assure you that I can hear them, and so can those organ builders who provide pedal stops that depend on the existence of this hearing phenomenon."

@HOW You said:

"You are also correct regarding the mixing of multiple frequencies in the ear, brain, soul or whatever since any two frequencies have resultants in summation and subtraction not to mention the harmonics. Too many resultants I suppose could result in pink noise."

Ref Colin Pykett's article on resultant bass, beats and difference tones (http://www.pykett.org.uk/resultantbass.htm), actually you have both inadvertently confirmed exactly what he is saying. Viz, that there is much confusion around these issues!!! I recommend you take the time to read the whole article carefully. A considerable amount of time I admit, as with all his work, but it is a complicated business.

Analogicus, are you REALLY saying you can hear tenor C if you play middle C and the G above? This is the experiment he suggests in his article. Surely not? Because if you can, your auditory system must be grossly non-linear. That is not intended to be rude because (again, as Pykett says) it is possible that some people do "hear" in this manner. It would be no different to listening to a very poor hi-fi system with high IM distortion. And I ask you this question with respect because, if I am correct, I believe you have an electronic engineering background. I would be very interested to get your answer to the question.

Regards

TG

[HOW]

Hello TG,
Actually, as an audio engineer, the subject of multiple frequencies, harmonics and phase shifting is very basic and simple, the complexities are visualizing and explaining what a particular individual thinks he or she is hearing. Just as in the subject of religion, basic Truth is simple. All the false doctrine is complex. ..... Just food for thought.
Best regards,
Stan

[Analogicus]

TG,

To answer your question, I most certainly CAN hear Tenor C if Middle C and the G above it are sounded. However, it must be admitted that it is at a very low level. And I don't think there is anything particularly wrong with my hearing. Let me suggest my own experiment: sound a fairly pure note well up in the organ manual compass, and WHISTLE a note within a few tones of it. If your whistled pitch is BELOW the sounded note, you should hear the resultant "sound" lower in pitch as your whistle approaches the pitch of the sounded note. Depending on the relativities, you can can some pretty unpleasant effects! (Surely this is what musicians refer to as "wolf tones", but let some of them answer for themselves. Hey - I would consider myself to be a musician, even if I do have an engineering background!)

Analogicus

[twanguitar]

Many thanks for your very interesting reply Analogicus. It confirms (as Pykett said in his article) that different individuals probably do have differing types of audio perception. He likened it to vision, where some people are color blind whereas others are not.

I do not hear any vestige of difference tones at all. I have just tried your whistling experiment with my home organ and do not hear anything like what you described. However please do not think I conclude that anything is wrong with your hearing. It is simply different to mine. Nor do I want you to think I am criticising your musical abilities either. However, the musician's "wolf" is an interval that is grossly dissonant rather than consonant, as in some unequal temperaments where "wolf" intervals can occur. This is unrelated to the current discussion about difference tones.

As for HOW, I am bowled over by your breadth of knowledge in both audio engineering and religion by concluding that (a) there is any similarity at all between them, and (b) that either are "simple". Maybe you will enlighten us mere mortals as to which university endowed you with a chair as a polymath.

TG

"He who knows not and knows not that he knows not is a fool - shun him"

[Analogicus]

TW,

I must say that I don't agree with HOW's remarks about where basic simplicity is to be found, but I don't think such discussion really belongs on this particular Forum. In fact I subscribe to the common opinion that the more we know, the less we feel we know. But for what it's worth, I certainly see no conflict personally in being committed to insights from the disciplines of engineering and theology simultaneously, so let ME bowl you over also: in my younger days I gained a graduate degree in Electrical Engineering from the University of New South Wales, and also a graduate degree in Theology from the University of London (as an External Student). As a much older person now, I value greatly what I have learnt from both disciplines!

Analogicus