Blog/Archive

Jul. 8, 2019

A pipe organ can attract all sorts of friends who want to BEE around it (photo).

Jul. 4, 2019

Recording the King of Instruments well is always a challenge but, when well done, it can be extremely rewarding.
This is a complex subject, thus only the most general information and pros and cons as it relates to nice sound are described here:
When contemplating the type and arrangement of microphones used to undertake such a task, one needs to bear in mind that no two pipe organs, even from the same builder, are ever exactly the same, and certainly no two halls, auditoriums, theatres, chapels, abbeys, churches, cathedrals, or residences are the same, so no exact information can be offered in that respect; in each unique situation it really is a case of experimentation and using the ear.
Since one would want a stereo recording in this case, the use of a spaced pair of A/B omni's (omni-directional microphones) are usually the first choice for the main pickup (photo).
Omni-directional microphones are microphones that pick up sound with equal gain from all sides or directions of the mic; this means that whether an organ pipe speaks into the mic from the front, back, overhead, left or right side, it will record the signals all with equal gain; this is very useful when the sound needs to be recorded from multiple directions, as when organ pipes are positioned in different locations within the room.
Big pipe organs are among the few instruments with a real low end worth capturing; for recording any organ which can sound 16-foot stops on low C, the sensitivity of the mics used should be able to capture frequencies at least down to 32Hz; for capturing sounds in the 32-foot octave, one would try to use a mic with a sensitivity down to as close to 16Hz as possible to minimize any non-musical ambient rumble; this will be possible because certain mics (albeit the most expensive ones) are sensitive down to 5Hz.
Tall mic stands can be helpful when recording a pipe organ, but since professional builders and voicers make their final voicings to sound good from pews/seats, not 20 or 30 feet up in the air, such stands should be positioned to pick up the signal in the room from where people are seated.
While finish voicers "tune" the organ for what it sounds like down at the listener level in the installed space, it's also the case that the best omni-mics don't hear sound with quite the same complex directional sensitivity that our brain-ear-pinna system does; we often "cheat" the mic much higher than listener level because it "creates" the same sound (as heard by the mic) that we hear with our ears down on the ground -- an added benefit being that getting the mics higher off the ground puts more space between the mics and any audience noise that may occur in a live recording.
These omni-mics would need to be positioned far enough away from the pipes that they take in the acoustics; the room is the dictating factor here; one should NEVER close-mic the organ, as it's not voiced to be heard from right up on the facade or from right in front of the tone grilles.
The capture of the room's ambience is ABSOLUTELY necessary for bringing the sound of the instrument together.
Beyond that there is no formula for mic placement, only good judgment by LISTENING on site for both clarity and room capture; the idea with mic placement is to arrive at a good balance between direct sound from the organ and natural reverb from the building.
The term Critical Distance describes the point, measured from the sound source, at which the direct signal and the reflected or reverberant signal are of equal intensity.
To find this Critical Distance requires a long tape measure, a sound level meter, and some means of generating a reasonably constant level of sound in the room which, in this case, should come from the area where the pipes are located.
One would start by measuring the noise level of the sound source at close range and making a note of the reading; this distance is then doubled and measured again; the noise level will have reduced by a certain amount because one would be in the direct field where a doubling of distance results in a halving of level.
One would then keep doubling the distance and measuring the drop in level from the previous position; while one is in the direct field, each doubling of distance results in a level drop, but as one nears the point where the direct and reverberant fields are equal in level, the level drop will get much smaller.
A change of only a decibel or two indicates that the Critical Distance has been found; further increases in distance will result in no significant change in level at all, because one is now in the reverberant field.
In general, organ lofts and pipework are built fairly high, and so a very tall mic stand or boom helps to get the mic(s) more on axis to the pipework; it's then a case of moving the mic around to get the best balance between the different divisions or sections.
If the organ is large and the pipework is installed in multiple locations, it may be necessary to use several mics to cover everything to attain the best balance; in the case of a pipe organ one may well be able to achieve an acceptable stereo effect using separate, panned, mono mics instead of (or in addition to) a stereo pair.
This is important because as one moves away from the pipes, the closer the mics are placed to the Critical Distance, the more reverberation will be picked up, and moving the mics closer to the source will result in a drier sound.
Recording engineers tend to go for a main stereo pair of mics to give the best overall balance and acoustic impression of the room, and then add additional (usually) mono mics if needed to reinforce a particular section or type of sound just to provide a little extra clarity or definition.
While the premise may be good, with pipe organs these additional mono mics, by giving certain sounds or voices a boost, will change what the listener actually hears from the instrument on site.
In an interestingly dry space where the reverberation may be less than one second, it's tough on the organist who has to adjust many things (touch, tempo, values of chords and intervening rests, possible release of final chords, etc.) to get the music to "sound"; it could mean abandoning for the time being the entire system of touch under which that organist was trained; the performer is faced with changing the score mentally to make the music the composer wrote on the page to come across; it's also tough to figure the Critical Distance for mic placement because the reverberation field is so small relative to the direct field.
The room is very much the "sound board" of a big pipe organ, thus the organist plays the room right along with the instrument; any time the acoustics are sufficiently dry like this, one would want all the hall one could get on the recording; sometimes a smaller spacing between mics improves the stereo picture a bit, but one would have to listen to know for sure; one might also experiment with an even more distant spacing from the chamber grille just to generate as much ambient reverb as possible.


Jun. 29, 2019

Every organist has the experience of noticing, more likely sooner than later, that organ pipes are like every other wind instrument -- their pitch varies with temperature.
Pipes will sound FLAT WHEN THE AIR IS COOL, and sound SHARP WHEN THE AIR IS WARM; the reason is, the air in the pipe is less dense when it is warmer and therefore oscillates faster.
Expansion or contraction of the pipe metal itself (photo), as it turns out, is negligible.
This is important for an organist to know and understand:
When a metal organ pipe is heated its length will expand a miniscule amount which, if nothing else were happening, would cause it to go flat -- however the air inside it will heat up at the same time, thus increasing the speed of sound in that air which will work the opposite way and sharpen the pitch.
Temperature indeed is a condition which affects the speed of sound.
Sound, like heat, is a form of kinetic energy; molecules at higher temperatures have more energy, thus they can vibrate faster; and, since they vibrate faster, sound waves can travel more quickly.
One way to think of this is: hotter air is lighter; the gas molecules in hot air are spaced farther apart -- colder air is heavier; the gas molecules in cold air are closer together -- thus, a pipe has less molecules of air in it when the room is warmer than when it's cooler, which affects the pitch that same pipe will produce.
If, let's say, a pipe is tuned at 70 degrees Fahrenheit, it will come back to that pitch at which it was tuned every time the temperature comes back to 70 degrees.
If, after that same pipe is tuned, the temperature increases to 75 degrees, the pitch of the pipe will begin to go sharp -- and if the temperature cools to 65 degrees, it will begin to go flat.
This isn't a problem for organs in environments where the temperature stays within 5 degrees plus or minus of the tuning temperature; it IS a problem if the temperature excursion is greater, which explains why pipes installed in attic locations where the roof of the building is also the ceiling of the pipe chamber need to be tuned more often -- why -- because attic temperatures shift widely back and forth, uncertainly.
Seasonally, the temperature typically fluctuates so much that most pipes won't hold pitch throughout the whole year, and, at the height of summer or in the dead of winter when the ambient air temperature in the room is, let's say, 87 degrees or 62 degrees, respectively, good tuning is simply impossible.
The speed of sound in room temperature air has been measured at 346 meters per second; this is faster than 331 meters per second, which is its speed in air at freezing temperatures, thus sound travels faster as temperature increases, and this increase in speed tends to increase the frequency we humans hear.
The speed of sound is also affected by other factors such as humidity and air pressure, but this effect of hotter air being inside the pipe on the frequency of the pipe is always greater than the miniscule expansion, or lengthening, that same hotter air creates in the length of the pipe -- and so, we find the former always overriding the latter and that the frequency of a metal organ pipe always INCREASES AS TEMPERATURE RISES.
Conversely, the more dense air inside a colder pipe oscillates slower, and this effect is always greater than the miniscule amount of contraction, or shortening, that same cold air creates in the length of the pipe, thus we find that the frequency of a metal pipe always DECREASES AS TEMPERATURE FALLS.
This can be demonstrated in a simple experiment using a cold open metal organ pipe and 2 tuning forks:
If we assume, for example, that the frequency of the cold organ pipe is 400Hz and a beat of 4Hz is heard when a tuning fork is sounded, the tuning fork could have one of two frequencies: 396Hz or 404Hz.
If the tuning fork has a frequency of 396Hz and the temperature rises, the beat frequency will increase because of the increase in frequency of the pipe.
If on the other hand the tuning fork has a frequency of 404Hz and the temperature rises, the beat frequency will decrease because of the increase in frequency of the pipe.
A high enough temperature could result in no beat, and an even higher temperature could eventually result in the beat frequency increasing.
Thankfully an organ will quickly come back into tune when the room's tuning temperature is reached regardless of how raucous it sounds when it's extremely hot or cold in the building; temperature extremes however are not as big a concern as are excessive seasonal variations in humidity, which can cause issues with certain wooden components in the organ.
Wood contracts, expands, and twists, for example, as humidity rises and falls, causing wood movement.
Good organ design can compensate for most of these problems, but serious wood cracking can develop from the extreme dryness caused by continuous winter heating for several days at a time.
The humidity gauge placed inside the organ chamber should generally stay above 30 per cent in the winter and below 80 per cent during the summer; prolonged humidity readings below 30 percent generally means that a humidifier is indicated, but it should never be placed near the blower intake of the organ; great care also must be taken to ensure that water cannot drip on any organ parts -- malfunctioning humidifiers and overflowing dehumidifiers can severely damage organ parts and windchests.
If the summer humidity readings are above 80 per cent a dehumidifier may be needed in the duct line to help the primary compressor remove enough moisture in the wind (pressurized air).
When the heating/cooling system of the building is turned on, stable temperature usually can be achieved inside the organ 3-6 hours afterwards; if outside temperatures are extreme, or if air does not circulate freely through all parts of the instrument, additional time should be allowed.
As long as the humidity remains below 80 per cent, the organ components should be fine even though the temperature in the chamber may rise as high as 90 degrees during the hottest weather.
If the pipes are enclosed and situated behind a tone grille, then keeping the swell shades open and removing the grille cloth wherever feasible will promote better air circulation within the pipe chamber.

Jun. 12, 2019

(con't from Part I)
Let's face it -- while the polyphonic work in general, and the fugue in particular, might be considered the organ piece "par excellence," this type of composition with its multiple moving voice lines, because of its dense texture, is not among the easiest pieces to learn.
Special pieces like this, for the majority of us, need to be learned a special way.
The watchword for learning an organ fugue therefore is "SUBDIVIDE," and the strategy involved is to permit "DIVIDE AND CONQUER" to guide the learning process [See Part I].
The thicker texture of these pieces demands that they be learned by first learning each voice, getting clear where we want the phrasing and breathing and keeping it the same every time another voice enters, then move to combinations of 2 voices, working out the best fingering and pedalling that works for us during slow practice, and only then attempting to put it all together.
Human beings learn very early in life that any kind of food too large to eat all at once first has to be broken down into smaller bites.
Four voice organ fugues, especially those with multiple countersubjects written in triple and quadruple counterpoint, can be thought of as the Dagwood sandwiches of the standard repertoire -- they cover the whole plate so-to-speak and are stuffed just as high and wide with all sorts of chewy stuff.
Listeners who keep track of all of the parts are going to be busy; while it's being performed, we the performer will be busier.
To digest our way through something like this we need to come at it the same way, i.e., little by little, a bite at a time, which is substantial time gained; we also have patience with the process and with ourselves knowing that, even if we don't seem to "get it" right off the bat, even if we think "I can't do this," even if we run into something that has us thinking "this doesn't work," it doesn't mean that we're never going to work our way through it, that we're never going to get this sandwich down (photo).
Never is a long time.
The basic plan of tactics then for coming at learning a 4-voice fugue (as this organist would advise, and as many college professors of Organ are quick to recommend) include the following, in this general order:
1. play at sight each voice separately and get to know it, all by itself;
2. determine which hand will carry the alto voice, and mark the score accordingly,
3. slowly sight read combinations of 2 voices beginning with the left hand part;
4. write down the best fingerings discovered from step No. 3 and do not deviate from them,
5. write down the best heel and toe pedaling discovered from step No. 3 and do not deviate from it,
6. slowly practice both hands together;
7. slowly practice the left hand and pedal, then right hand and pedal, then put it all together;
8. do not skip steps.

Jun. 3, 2019

When we first sit on the organ bench the toes of both shoes are placed in the spaces in the middle of the pedalboard between the sharps (photo); from this initial position of orientation, centered directly above the pedal D key in the middle, the feet then learn to "feel" for any pedal key adjacent to these 2 spaces and, from there outward, are taught to find all the rest of the pedal keys the same way, i.e., by blind feel.
This means that, in the case of a 32-note pedalboard (low C to high G), the high pedal F, F#, and G keys will seem further away than the low pedal C key.
These 3 very high pedal keys are very difficult to locate merely by feel; anyone who has ever missed the pedal high F in the opening of the Widor 5 Toccata has been made painfully aware of this fact and has learned that it's better to take a quick glance downward at the pedals than to play a wrong pedal note.
In addition, the pedal keys are not all that an organist's feed need to find -- there may be one or more swell shoes, a crescendo shoe, and/or perhaps one or more rows of toe studs positioned above the toeboard (photo); on some of the largest instruments in fact, additional banks of toe studs may be supplied outside both ends of the pedalboard.
The positioning and configuration of these various accessories varies from instrument to instrument -- thus, with no two instruments being precisely alike in this respect, the "feel" employed in one application does not work in another.
So, do concert organists with virtuosic feet -- who possess footwork including trills, arpeggios, and four- and five-note chords -- who routinely perform pedal-heavy pieces in public on all styles and sizes of pedalboards besides the Guild standard -- ever look down at their feet? ... oh yes.
And it is NOT cheating.
We should, of course, strive to master that kinesthetic sense of being able to find pedals without ever looking down, but -- especially when we're playing at the extreme ends of the pedalboard on an unfamiliar instrument -- as long a taking a quick glance at the feet does not interfere with the rhythm of the music and the eyes can be brought back quickly -- either to the manuals or to the place on the page where they need to be -- looking down for a brief moment is perfectly all right.
Many professional musicians who have achieved considerable excellence in organ playing have done so by adopting the habit of looking at their feet during performance -- some for a good bit of the time [See menu bar, Videos, Bach Passacaglia].
Lighting to illuminate the pedal keys is very often introduced by organ builders for this very reason -- for those situations where the player desires a glance downward for a moment.
Bottom line: unless we're extraordinarily gifted, we can't do well what we can't see well -- and this applies to playing the entire pedal keyboard from top to bottom.