Transparency -- the missing quality in many digital organs?

[jbird604]

Well, I guess I have too much time on my hands these days (and it's not for lack of work, or for lack of need to practice either!), but I sometimes find myself pondering those questions that have burdened the great minds of the human race for eons. Such as "why do some digital organs sound good to me and some don't?" (Ok, maybe Socrates never addressed this topic, but if he were alive today he surely would, right?)

A word that came to my mind as I pondered this subject today, thinking about several organs I've played lately, was "transparency." And I'm not entirely sure that I can define it. But it seems as good a word as any to describe the quality I'm thinking of.

You know how, when you're listening to a wondrously voiced pipe organ in a magnificently endowed acoustic space such as an historic cathedral -- and the sound really seems to just BE THERE. In the room, in the air, in the floor, in your chest, in your gut. It's not like you're thinking, "that sound is coming from that spot over there, inside that box, behind that screen." Instead, you're blissfully unaware of just WHERE the source is. You see display pipes, a lovely case, some less adorned pipe sets on a shelf or along the quire aisles. And you know that somewhere there are the very pipes that are lovingly responding to the stream of air passing out the flue and caressing the upper lip, thus eliciting a whisper or a roar that transcends description.

But how often does one experience the same in a typical church or hall listening to a typical digital organ? Not often enough, I'm sure.

Yet, now and then, it actually happens. Sometimes on a grand scale, as when one of the great digital builders produces a masterpiece that also happens to reside in an acoustic space that transforms the plain tones from the speakers into the ghostly spirits of the pipes that were sampled.

And for me, most frequently, it's when I'm listening to a Hauptwerk organ through headphones. I don't have an actual Hauptwerk setup of my own, but I can listen on Contrebombarde.com to the finest of them, played by some excellent folks, and when I do, I nearly always feel that I am truly in the presence of pipes producing TRANSPARENT MUSIC in a lovely space that may be a thousand years old.

I don't get the same sensation when I listen to even a very nice modern digital (such as the one in my home) through headphones. Someone recently asked me what it's like to listen to a digital organ with headphones, and I said "like there's an organ playing in your ear." And that's not where we are wanting to hear organs playing.

But there are certain modern digital installations where I have indeed heard something very close to the transparent sound that one gets in that perfect space where organ and room unite. I won't say that it depends on the builder, because I have heard it from more than one builder. Or that it simply depends on the room, important as the room may be. But there is something that some organs have and some just don't.

And I'm calling that something "transparency." If I can discover how to make an organ transparent, I will change the world.

[toodles]

For me, it is a matter of clarity--and perhaps that is the same thing you are trying to describe. A well voiced pipe organ (and It need not even be in an extremely large acoustic space) has a clarity and a warmth to it that seems to elude electronic imitations, or is at the very least, extremely hard to achieve. Maybe it is that the only distortion in an acoustic organ is that that occurs in our hearing, and that all electronic processing produces distortion to some extent.

I wish that you would find the answer!

[nickp82]

Very interesting thoughts :)
It makes me wonder if part of it is also similar to whenever I listen to an analogue source of music such as a vinyl record or cassette... In later days, you also had the (fairly pointless, IMO) records and cassettes that were made from digital masters and these did not have the feel of the pure analogue originals either.

There seems to be an extra 'ethereal' kind of depth to the audio over and above the digital recordings. Is it to do with the analogue being an infinite domain compared to digital where even though the resolution is extremely high these days, it's still a 'chopped' and sampled signal? I think despite the advances in digital reproduction, the human ear/brain can still perceive the difference somehow.

[myorgan]

John,

Perhaps the word you're looking for is presence. The sound you're describing is a present and all enveloping sound the listener experiences rather than listens to. The last time I remember feeling that way about an organ was 5 years ago in Altenberger Dom, Germany. The organ was felt rather than heard. I would imagine the space had something to do with it as well.

Michael

[jbird604]

I know that this quality I'm seeking is not an absolute. There can be none of it at all -- as when listening to the most artificial and lifeless tones of some old cheap clunker. The type of sound we heard from the original Nintendo video games. But more often there is just enough of it to make you long for what's missing.

For example, you may try out a new organ and think "they got pretty close here -- I still can tell it's a speaker organ, but at times the sound does indeed seem to float in the air without any apparent source." Or you might think they were beginning to get on the track, but didn't follow through -- there's one stop that's right, but most of it is dead and flat.

The saddest is when I hear an expensive new-ish organ -- one built in the past 20 years or so, since sampling became a commodity and perfect rendering a dime store product, and which cost well into six figures -- and realize that it sounds as artificial and two-dimensional as anything else out there. While the samples are obviously top-notch and the organ's hardware is undeniably excellent, the job was done by pros who know good organ sound, it just doesn't transport anybody to organ heaven.

Part of it may depend on how UNSTABLE the tones are. Allen and Rodgers both figured out in the analog era that oscillator tones sounded more pleasant when modulated by some random noise or fluctuation. Allen analogs had "RMW" and gyros. Early MOS organs had gyros, and later that "jitter" or Random Motion board to make the pitches less pure. Digital builders talk about "wind pressure" and such and random de-tuning, all methods for messing with the pitch stability.

But we have to go beyond simple pitch instability and find a way to create LOCATION INSTABILITY -- the sense that the sound source itself wanders about in some way. Sort of the way the Leslie speaker transformed the Hammond tone wheel organ. I suppose that the sound coming from a real pipe has some kind of variable directionality -- as the pipe mouth "spits" out the sound, minute irregularities in the edges of the flue and lip may cause the radiated sound to shoot out in randomly-changing directions. With this going on simultaneously in dozens or scores of individual pipes at any given moment, the organ seems like a living, breathing organism rather than a lifeless piece of hardware.

The concept of "stereo imaging" may hold some promise. And I hear what I'm listening for sometimes in a good stereo-sampled organ, though not always. But I think part of the trick may be figuring out a way to generate that random movement more effectively than we have yet done on a consistent basis.

The genius of Hauptwerk is probably in several things it has going for it -- the sampling is indeed in stereo, and with long samples, that variable directionality of each pipe gets captured; and the inimitable contribution of the acoustic space is captured right along with the pipe sound. That's great for personal enjoyment at home, but of course in church or in a concert hall we don't want to simply bring a copy of a good organ somewhere into the room, along with its acoustics. We want to play on a lively organ and have it sound beautiful in the space in which we are.

[abacus]

Vinyl, Cassettes etc. are severely limited in there capabilities, (Noise, Dynamic range, distortion etc.) but have warmth about them that makes them alluring, however they are not reproducing the original sound accurately.
Quality digital recordings are capable of recording way beyond what the human ear can discern, however they appear to lack the warmth of analogue.
When you compare live instruments to analogue & digital recordings of them in the same place, you soon realise that analogue is not as good as you thought it was when it comes to accuracy.
Take a quality digital recording and compare it to vinyl and you will hear a difference, however record a vinyl recording to a quality digital recorder and they will sound identical, as the digital recorders capabilities are way beyond the vinyl capabilities.

The biggest variation in sound is the room itself which imparts its own sound character, (Which can be either positive or negative) however when you put on a pair of quality sealed headphones then all you hear is the recording, which if it has been made using microphones in the room itself where the instrument is, means you get everything without colouration, and it can sound sublime.
To get around this you need to acoustically treat the room and use quality room correction software, (To make the room disappear) then use convolution reverb to get the room you want.
Yes, cheaper instruments have to cut corners, but a quality instrument is only limited by the speaker system and the room it is in.

Bill

[m&m's]

For me, stereo imaging is the approach to this desire for transparency. While my Galanti Praeludium may be outdated by all of the newer organs, it is a wonderful experience to play through ten audio channels, set up as five stereo outputs, and hear the sound of the Great and Pedal bounce back and forward from side to side as I play. Also, the Swell has its own stereo sound on one side of the console, and the Choir on the other. I have never had this much satisfaction from the Allens that I have played over the years.

I realize that newer organs may have more memory, and use more samples, and that they might use random tuning, but I do not tire of playing this organ over a long period of time. I am preparing to build a large theatre organ (over 125 stop tabs) using Artisan equipment including sound engine, but using Hauptwerk samples, and am planning for the same five stereo outputs. I plan to use this in gospel concerts, and maybe some public concerts, and hope to get the same results in those situations.

[jbird604]

Mike, are the stereo pairs of your Galanti similar to the Rodgers "parallel digital imaging" concept, or are they more like C-C# divided chests? Any kind of stereo field is bound to help a digital organ seem more transparent by making the source of any given stop less localized.

I know that Allen used a C-C# scheme on nearly all the stops in larger Renaissance organs (and presumably on today's models), but that of course was a different thing from the "PDI" concept touted by Rodgers for so long. I've heard good organs based on both concepts.

Also -- do you have any kind of digital reverb on your Galanti at home? How is it configured?

[m&m's]

Mike, are the stereo pairs of your Galanti similar to the Rodgers "parallel digital imaging" concept, or are they more like C-C# divided chests?

John, in answer to your question, they are divided in C-C# fashion; however, they do reverse the sides several times going up the rank. For instance, the Great 8' Principal reverses at Middle C and again at the next C. Also, I do have reverb on the console, set to low to medium level. I have never checked to see if each channel has individual reverb, or if it all goes through the two main channels. Probably the latter, since there are potentially 16 output channels on this organ-separate flues and reeds on each keyboard including pedals. Needless to say, I am not using all of those outputs!

As I have mentioned before, I have had the opportunity to hear and play the very large organ in the Methodist church in Hurricane, which has about forty ranks of pipes and at least a hundred ranks of Walker digital samples, and I could not tell which ranks were digital and which were the real thing. I have had the sound experience with other pipe organs to which several Walker ranks were added. Also there are a number of videos of M and O organs on Youtube, and the only difference I can tell, between them and other similar recordings of pipe instruments, is that the M & O organs sound better! They certainly don't sound the least bit electronic.

[Jay999]

Hauptwerk uses a "random motion" set up by playing a repeated note through another speaker. There are four speakers for the left side of the sound stage, and four speakers for the right side of the sound stage. Whenever you play a single note, it will move to another speaker when you repeat it, and will move again to another speaker when you repeat it a third time. The Hauptwerk program is sophisticated enough to choose the correct speaker to play separate notes of a chord through different speakers, so you never encounter distortion going on, as a result of two clashing harmonics that would frustrate the motion of the speaker. At least that's the way it works in theory, and most of the time, it works better with two, three, four or more speakers, playing those dissonant kinds of harmony, rather than pushing it all through just two speakers....like you find in a C - C# setup.

Walker uses this same principle, except their samples are much more highly 'refined' in voicing and regulation.

From my own experience, I have found extremely better tonal results in building a pipe organ chest, using the diminished chord as the basis of pipe layout, rather than the C - C# layout. The European builders have done this for centuries, and possibly, some of us have listened to this type of layout, and remarked how much more highly defined, or well voiced that particular instrument is, not knowing what's going on inside the instrument.

[jbird604]

That is a capability of Hauptwerk of which I was not aware, Jay. But a wonderful concept. I assume this is something that the free version can't do though. I'd love to hear such a system in operation. No doubt it would go a long way toward making the sound more "transparent" and creating the live motion that is so interesting in a pipe organ.

[Admin]

Hauptwerk uses a "random motion" set up by playing a repeated note through another speaker. There are four speakers for the left side of the sound stage, and four speakers for the right side of the sound stage. Whenever you play a single note, it will move to another speaker when you repeat it, and will move again to another speaker when you repeat it a third time.

That is not quite correct. There are several Hauptwerk routing algorithms, but none of them cycles repeated notes to different channels.

The Hauptwerk program is sophisticated enough to choose the correct speaker to play separate notes of a chord through different speakers, so you never encounter distortion going on, as a result of two clashing harmonics that would frustrate the motion of the speaker.

Hauptwerk routing algorithms fall into two categories, cyclic and tone matching. Hauptwerk creator Martin Dyde charts the tone matching modes for various numbers of channels in this document.

The algorithms for the cyclic modes can be found in the thread linked to below.

[jbird604]

Thanks for the links. Interesting stuff here.

[AllenAnalog]

Having the source of a sound move around when a note is repeated would not be "natural" to the way organ pipes sound. I found this comment by Martin Dyde to clarify things:

"Although routing pipes dynamically to different speakers depending on the pipes that are are already sounding could potentially give some benefit in terms of reducing the load on the speakers (helping to minimise speaker distortions), Hauptwerk intentionally doesn't include that functionality natively since it wouldn't be realistic, in that any given virtual pipe would then be heard to move seemingly arbitrarily around the listening room each time it was played, whereas each real organ pipe always sounds from a fixed point in space. I think you would find the effect noticeably unnatural."

[Jay999]

That is not quite correct. There are several Hauptwerk routing algorithms, but none of them cycles repeated notes to different channels.


Hauptwerk routing algorithms fall into two categories, cyclic and tone matching. Hauptwerk creator Martin Dyde charts the tone matching modes for various numbers of channels in this document.

The algorithms for the cyclic modes can be found in the thread linked to below.

Thanks for the explanation on Hauptwerk. I stand corrected!

[samibe]

I had thought about this a bit a few years ago. There is something about making/listening to music in a reverberant space that is awesome and it's not necessarily the length of the reverb tail. I'm pretty sure the reverb tail in a bathroom is less than a second. My description was along the lines of being enveloped in sound. Singing in the bathroom is fun because the sounds seems to come from everywhere at once. Maybe that's what you're getting at with your transparency description.

[jbird604]

Sam,

Good points. Singing in the bathroom is an analogy I had not thought of! But it does contribute to my point. Music is somehow enhanced by this ambiguity of source. That is one reason why music coming through a PA system is so terrible, as PA systems are generally designed to send their output directly into the ears of the listeners, bypassing all the reflections. You can't help knowing exactly where the sound is coming from. Many modern PA systems even include digital delay processors so that people sitting farther back in an auditorium hear their PA speaker sound delayed so that it won't seem separated from any possible stray sound from the speakers up front. This may be fine for the spoken word, but this is not the way music is naturally dispersed and enjoyed in a large room.

OTOH, there is still something "else" involved in "transparency" of organ tone. If it were simply the sound coming at you from multiple directions, then it would take nothing more than multiple speakers placed around the room carrying the organ sound. Like the music in the mall -- speakers in the ceiling throughout the mall, all carrying the same monophonic signal. That works for getting the sound evenly distributed (more or less) throughout a large building, but it doesn't make the sound any more realistic or engaging or enjoyable.

Rather than multiple sources of direct sound, it seems to take multiple sources of REFLECTED sound to create this transparent field. That's one reason that I like to lay the organ speakers on their backs and have the sound reflect off the ceiling when a room is too small for the regular wall-to-wall reflections to be useful. This only works of course if the ceiling is actually smooth and hard, rigid enough to bounce the sound back and not simply absorb it.

I'm still not sure that this is the only factor. But we may be onto something important. Think of how effectively a Leslie speaker enhances the sound of a Hammond organ. That sound being thrown around, reflections coming back from various surfaces all over the room at different levels, different distances, random delays, the shifting of phase and level, doppler effects -- all combine to create a dramatically richer musical experience than a stationary speaker carrying the exact same signal. The sound seems to come from "everywhere" but not just as a multiple identical sounds. All those (infinite) variations seem to be quite distinct from one another in some way.

While I'm not advocating adding a Leslie speaker to anybody's classical organ, I am looking for the key ingredient to make a digital classical organ produce the spacious sound that we all love so much, even when the environment is less than ideal.

[AllenAnalog]

On Sunday I went to a service at an Episcopal church where they have a relatively new Johannus Ecclesia D570 organ. The 1920s sanctuary seats about 350 and is mostly hard surfaces. The room was about 1/3 full. There was an 8 member choir and the congregation sang the hymns and responses with great enthusiasm. (Good news in this world of such things being in major decline.)

The organ speaks sideways into the front of the church out of the chamber openings of the former pipe organ. I cannot tell if the swell shades from that organ were removed or are just propped open since there is grille cloth behind the decorative molding. I also have no idea how the speakers are positioned within the former pipe chamber. There are some smaller speakers visible at the front and back of the church near the peak of the vaulted ceiling which I presume are for antiphonal use. The organist is an AGO professional and there is no electronic reverberation turned on.

This is the second time I've heard this instrument and it sounded just as "electronic" yesterday as in my first hearing. I discerned no initial speech transients or other clues that this is a fine, expensive sampled organ capable of fooling the ears into thinking the original pipe organ is still in the chamber. I would presume that the speaker installation and voicing are to blame for that.

My high frequency hearing is diminishing but I know I get more authentic "pipe" sounds from my 1989 Allen ADC-5300 and a recent visit to another church with a pipe organ confirmed that I can still discern that elusive authentic "pipe sound."

My rating for this installation: "Transparency" = 0

[jbird604]

That seems a shame. A room like that ought to be a good place to enjoy an organ of any kind. Maybe it's the fact that the chamber openings are "sideways" -- does that mean they face in toward the chancel but not out toward the nave? Obviously, that makes it much harder for the tones to do much bouncing off the ceiling and walls of the nave. In my own church, that is how the chamber openings are, but I've placed speakers at floor level on the back wall of the chancel, directed up at the ceiling, which I think helps get the sound out into the nave better. Still not perfect though.

[Admin]

Like most attempts to characterize a sound quality, what is meant by "transparency" is open to interpretation; however, I think a discussion of the acoustical environment, especially regarding reverberation, misses the point of this thread's title, "Transparency -- the missing quality in many digital organs? "

Note the qualifying "digital organs".

If reverb and sound reflectivity are components of "transparency", then we're no longer talking specifically about electronic organs, analog or digital but acoustics in general, which is a whole other topic.

I've been to many pipe organ installations in homes that have been acoustically dead, and yet, the sound of pipes has an open, living quality, that even the best electronic installations with finest of samples and voicing fail to capture. It is that difference that I would characterize as "transparency." From this observation I would say that "transparency" is related to the number of sound sources and in an electronic installation that translates to the number of individual channels.

The more channels, the better, because greater channel counts reduce phase cancellation and intermodulation distortion while increasing the size of the sound stage.