Glenn D. White has had a long and varied career in acoustics, sound reinforcement, education, studio design and piano and organ repair spanning over 40 years. He has worked with people such as Kearney Barton [Tape Op #83] (of Audio Recording, Inc.) and acoustics genius Paul Veneklasen — and he also did the sound for The Beatles at the Seattle Coliseum in August of 1964! He also wrote a textbook called, The Audio Dictionary (UW Press) that is now going into its third edition. All in all quite a range of experience for someone who was born on a wheat farm in Kansas and grew up on Queen Anne Hill in Seattle. With a wry sense of humor, he sat down and answered my many questions.
Where did you go to school?
I went to the University of Washington, majoring in Physics. I got my degree in 1955.
Were there classes in acoustics and how did you find out about them?
I investigated the Physics Department at the University of Washington and I found out that Professor Kenworthy was an acoustician. I read a couple of the papers he had written for the Acoustical Society of the American Journal, and I thought he was a really sharp guy. I was offered a scholarship at Wazzu (Washington State University) for their Physics Department, but they didn't have any acoustics guy and they didn't have any Acoustics curriculum either. It wasn't that expensive to go to school in those days and I lived on Queen Anne Hill with my folks... Dr. Kenworthy was my advisor.
What was your first job?
The first real job that I had after I graduated was at the Boeing Company. I had hoped to be able to get a job in their Acoustics Lab, but they were not hiring anybody at the time. However, right next door to it was the Vibration Lab, in the same building (this was at the old Plant 1 building Boeing facility), so I took a job in the Vibration Lab. They had an opening in the Tape Room, which is where they did Data Analysis (handling all the data that has been recorded on tapes. Mostly data from accelerometers and velocity probes and occasionally microphones). I liked that — I knew how tape recorders worked. I stayed there for about 8 years. When I left there (Boeing), I was in charge of Instrumentation for their Environmental Test Lab.
Why did you leave your first job?
I left my first job to become the first sound engineer at the Seattle Center, the location of the Seattle World's Fair of 1962. That's the first I had heard of Paul Veneklasen, who was doing the acoustics at the Opera House. The Opera House was going to look for a sound engineer to work with Veneklasen, to do some more acoustical changes at the Seattle Center and also to be in charge for sound reinforcement for the entire Seattle Center.
Who was Paul Veneklasen?
He was an acoustician who lived in Santa Monica, and he studied at UCLA. He had been a student of Vern Knudsen, who was the relatively well-known acoustician that had worked with Harvey Fletcher [of Fletcher-Munson fame]. Paul Veneklasen and I had a nice relationship because we seemed to speak the same language and we seemed to think the same way — I learned a tremendous amount about acoustics from him. He was really my mentor in architectural acoustics. Kenworthy was a theoretician, and I got all the theory and all the rigor from him, but as far as practical acoustics was concerned Veneklasen is where I really learned that.
What effect did working with Paul Veneklasen have on you?
It taught me a tremendous amount about auditorium acoustics. Also about the politics of dealing with architects, which was (and still is) a real problem with a lot acousticians. Mostly he was my mentor.
How long did you work at the Seattle Center? What was your most significant experience there?
I was there for five years [1963-1968]. The most memorable experience was when I was doing the sound for The Beatles in 1964 in the Seattle Center Coliseum. The Beatles sent two guys from New York ahead of them. They asked me about the sound system, and they said, "Can you augment the system to make it just as loud as possible. Getting the music over the noise of the audience is going to be really difficult." And I said, "Well yeah, we have quite a bit of equipment around here, so we can add to the system." All of our amplifiers in those days were 80 watt tube amplifiers. So I added three Altec/Lansing 300 Hz two cell horns (model 203, on 288 C Altec drivers). I put two of those, one on top of the other, facing one of them back to cover the far end of the auditorium, the other one facing down a little bit to cover the far end of the main floor. Then we had some 800 Hz horns, also Altecs. They were 805s, two rows of four cells each, and I had one of them pointed right down on the stage so that The Beatles could hear themselves and also cover the audience close to the stage. I had to scrounge amplifiers from other locations around the Seattle Center and put them in there. Each of those horns was driven by its own 80 watt amplifier and the woofers were JBL 15" woofers.
How did you overcome all that screaming?
We didn't. During the screaming, the sound system was inaudible... It was a big wave of screaming and then that would die down until they could hear a few words and then there came another wave of screaming and so on for the entire twenty-two minutes The Beatles were on stage. I used EV655C microphones for the four performers. I used one mic for Ringo and his drums. Those are omni directional dynamic microphones. Very good quality dynamic microphones. The Beatles were really intrigued by that. They said, "These microphones are so small. How come they're so small?" I said, "They're small because they sound better when they're small." "Oh is that so, really? No kidding!" Ringo tapped the mic with his drum stick! He'd say, "Is this really working?"
How did you deal with the hysteria?
I just put in ear plugs and tolerated it.
Did you do sound for any Northwest bands?
There were a lot of local groups too. One group I liked was Paul Revere & the Raiders. I think they were from Portland. Their drummer [Michael "Smitty" Smith, RIP, 1942-2001] was terrific. We [also] had the Wailers.
Why did you decide to leave the Seattle Center?
I was offered a job by Bill Bergsma, the director of the Music School at the University of Washington, to become the University Acoustician. Also, I would have an instructor's position in the Arts & Sciences department. I would teach a course in Electronic Music and Recording and Reproduction of Music and Musical Acoustics. So I thought, 'Wow that's good, I would like to do that', so I quit the [Seattle] Center, and went to the University. I was there for thirteen years. That was a very good job — I really enjoyed working with the kids.
How did you come to meet Kearney Barton of Audio Recording, Inc.?
Well he was around for a long, long time. When I was in school he was around. I don't remember how I met him. I knew when he moved his studio from downtown up to 5th Avenue about Cedar St [2227 5th Ave]. He rented some space in there and he called me and wanted me to look at the space to see if he could put a studio in there.
What were recording studios like in the '60s in Seattle?
There was a lot of two channel stuff around, but Kearney wanted three channels and he wanted me to build him a console. My assistant at the Seattle Center was an excellent electronics technician, Ken Heidt. Ken and I built a console for Kearney in 1965 [which he still owns and uses!]. It is a total custom job. The console uses all Langevin pots and passive graphic equalizers. It's only three channels and everything is interconnected by patch cords, which I thought was a good idea.
What made Kearney's place so special? What was significant about it?
The console sounds very good. It has those Langevin preamps, which are push-pull from the input to the output. It's two channels in parallel on every preamp — they are very quiet and sound really good. They hardly overload, but if you do overload them they smoothly overload — they don't sound bad when you do that. The line amps were also Langevin and a very good design. I thought they were quite a bit better than the Altec designs at that time. I think the electronics in there were good. For tape recorders he had Ampex 351-2[track] and he also bought a 3-track Ampex MR70, a half-inch machine. He didn't use that very much because nobody wanted 3-track. Kearney still has that machine at his present studio and he converted it to 4-track, and he took out that 3-track head assembly, which is still almost brand new.
What about the room?
We had to use the room at the size that it was. It was fairly decent sized [750-800 square feet]. We built a control room adjacent to it, not very deep but it was wide — space was limited. It sounded all right. We put some fiberglass on the walls at various locations to get rid of echoes and stuff. The cement slab went from his studio to the neighbor to the south who had a woodworking shop and all of his tools sitting on the concrete floor. His machinery would transmit vibration though the floor and into Kearney's studio. We built another wall right across in front of the existing wall, and isolated that. Kearney finally got the neighbor to put cork pads under his equipment to lower the vibration from them.
Were there any other obstacles that needed to be overcome?
The place was not very sound proof. Aircraft noise was a problem. Once in a while a loud airplane could be heard in the studio. Kearney used [Altec] A-7s for monitors in there, three of them. I thought they sounded awful, but he was used to them.
How many reverb chambers did Kearney have?
There were three. They were similar in size, but with different shapes, so they had different characteristics. They didn't sound all the same but they weren't drastically different. If you wanted stereo reverb, Kearney decided that that he wanted three-channel reverb (use one for each channel on his three channel system). The problem is, since they were different shapes, the reverbs didn't sound identical. It's much better off putting three mics in one of them and spacing the mics out.
What are some basic principles of acoustics to remember when designing and/or building a recording studio?
In general, a recording studio should be as big as you can afford to make it. There is no such thing as a recording studio that is too big, but there are lots of them that are too small. If it's small then it has to be really dead. Otherwise, the room mode resonances of the place will interact with the music. It's the boundary reflections and to a lesser extent the reverberation of the room that gives it its acoustic and musical character. If you get rid of that by making it completely dead you might as well perform out in the middle of the desert, you don't get sound coming back. A lot of people make mistakes in the ceilings in recording studios. The ceiling should be a diffuser, or a relatively good absorber, because you don't want a specular reflection off the ceiling. I have been in lots and lots of studios that had just plane surface ceilings, even if angled, if it is a plane surface, it's not good.
Do you have to spend lots of money to get good acoustics?
Lots of money is a relative term depending on who you are talking to. [laughs] It depends on the requirements. If you have a sound isolation problem then it is going to be a lot more expensive to control that. You have to take special pains to isolate the noise sources from the studio and control room. That requires multiple walls and it requires special treatment of those walls, etc...
What is important to remember about control room acoustics?
Control room acoustics: that's a controversial subject. Nobody seems to agree on what they should be. You have the Live End/Dead End controversy (where one end should be live and the other end dead). That is a non-symmetrical acoustical space, and I don't think it sounds very good in either location, either at the live end or the dead end. I think the control room has to be deader than the studio is, because you don't want the natural acoustics of the control room to interfere with what you are monitoring. You want to hear what the studio sound is. It should be dead, the whole place should be relatively dead. In my opinion, a live end is not a good idea.
Is it a matter of taste?
You have to design the studio to satisfy the guy who is paying the bill. It isn't always to my liking, but if it is to the customer's liking then that is okay with me.
Are there a lot of "Flavor of the Month" ideas that come through when you are working with a customer?
That's what the Live End/Dead end thing was. That was the fad for a while.
What monitors do you like and/or dislike? Is placement essential?
Placement is essential for sure, and you have to experiment to find that out. As far as like or dislike I really don't have any preferences. The guy who is using it always has preferences — he always knows what he wants in my experience.
What about soffit mounting speakers?
Usually the soffit is too high and I think it is better if the height of the speaker is not that different from the height of the engineer's head. I think if it is too far above you, it doesn't give you the proper tonal image.
What about field of dispersion?
You don't have to have a very wide dispersion in monitors, because you are going to orient the monitors so that the sweet spot that they generate is right where the engineer is. If there is too much dispersion, then you may excite too many of the room modes and you don't need that. Not that you couldn't deal with that, but why have to fool with it?
Is there a formula, or is it by eye and/or ear?
There are ways you can calculate it. You can measure the critical distances in the room (which is the point at which the direct sound and the reverberant sound are equal in level) and that will not be too far away from the speaker in a small room. You want to have your monitoring position within that critical distance. The speaker itself will have a directivity cone, where most of the energy is, at least at high frequencies, of course at low frequencies they're not directional at all (especially small monitors). But the high frequencies above 700 or 800 Hz is where it is really important to get a relatively narrow distribution, if you don't want to excite all the room modes.
How do you "tune" a room?
Probably the most troubling thing about a room is the existence of flutter echoes and very strong room modes. A room mode is a situation where sound bounces back and forth between two parallel surfaces and it interferes with itself either destructively, or constructively at different locations. The sound of that particular frequency is very non-uniform in level in the room. You get right up to the wall and it sounds really loud and you get out to the center of the room and it could be very soft. If it is a higher frequency, in other words if it has several wavelengths between the two surfaces, then you got this up and down variation in level just by changing your position by a few feet. You have to eliminate that in a room. You do that by selective absorption and also by using angles, you don't use rectangular shapes.
What are some tools that people use to tune rooms?
People use a lot of stuff. There are people that use various software programs to try to optimize a room. These are approximations. I don't like any of them that I've heard. The best way to tune a room is by ear. Your ear is an amazingly sensitive measuring instrument if you train it. That is one of the other things I learned from Veneklasen.
Any common errors that people make in control room acoustics?
Usually the control room is too small, then they have to make it really dead, to prevent it being like a boom box. That is the most common problem I run into.
What is an "echo/reverb" chamber? How does it work?
An echo chamber really shouldn't have any echoes in it. An echo is a discrete reflection, and you don't want that. A reverb chamber wants to have a completely diffuse field, so that if you're in there you have no idea where the sound is coming from — it's all over the place. You can make a fairly small reverb chamber with a fairly long reverberation time. You wouldn't want to record in a reverberation chamber, because the reverberation is too high in level and too long, but also it is too close to the direct sound. You might want to do that for a special effect, but it would not be good for general recording. The thing to remember about a reverb chamber is that you have to delay that reverberated sound into the mix that you are making, delay it with respect to the sound from what went into the chamber. That delay will give you the subjective impression of how big the room you are trying to simulate is. If you have a long delay then it will sound like a cathedral and if you have a shorter delay, it will sound like a smaller room, etc... But I don't think that digital reverb, or vibrating plate reverb, or spring reverb is anywhere near as good as actual three dimensional acoustic reverb. It gives a true logarithmic decay curve, whereas these others don't do that and they don't sound natural.
What are the advantages of building one?
The advantage is that the result is the best reverb you can get. You can't do any better than that if the chamber works. The pitfalls of a reverb chamber are that you have to avoid standing waves in them. You have to be really careful about the dimensions and avoid parallel surfaces and square corners. They don't have to be gigantic either to really work.
How would someone design and build one?
The walls of the reverb chamber should be as stiff and solid as possible and concrete and/or concrete blocks is a good material to use. You can make them out of lath and plaster, but you have to use lots and lots of plaster. The surface density of the boundaries in a reverb chamber should be about at least ten, or fifteen pound per square foot. The easiest way to do this is with concrete block, or with just cast concrete. Sometimes you are lucky and you find a concrete enclosure in a building that you can adapt to be a reverb chamber, like a space under a stairway, or a stairwell. You've probably been in stairwells in buildings that just echo all over the place. My friend Joe Boles, [who recorded "Walk, Don't Run" by the Ventures] did a lot of home-studio recording back in the '60s. He used his downstairs bathroom as a reverb chamber. He put an Ampex 620 in it for a speaker and he used a [EV] 655 for the microphone. He used a tape delay and it didn't sound bad. It has to have a good solid door and it should be a sound proof door if you can afford it. You have to keep background noise out of it. Ideally the reverb chamber should be a long way away to avoid sound leakage into or out of it. It could be in another building. Capitol Records has theirs underground, under the parking lot. They're huge. Each one is as big as this room [750 square feet] and they're all concrete — talk about reverb!
What kind of mics would you use in a reverb chamber?
You need an omni directional microphone and one that has as flat a response as possible. A good choice is an Altec 21, if you don't have too much low frequency noise in there, an [EV] 655 is a good dynamic mic, or a Neumann KM83 is a very fine microphone. Veneklasen did a lot of experimenting with reverb chambers and told me that the best place to put the microphone is glued into the corner about a foot or eighteen inches from the ceiling or the floor, but actually glued right into the wall. If the microphone is right at the surface, then you don't have any reflection from the surface coming back into the mic. If you put a mic a foot from a wall and a sound hits the microphone and then the wall, at some frequency the reflected sound from the wall is going to cancel the direct sound, because it is 180 degrees out phase. Your response curve is going to look like a picket fence.
What about a PZM mic?
A PZM mic would be fine, if you mount it on the wall of the reverb chamber. You don't have to have a PZM mic, all you have to do is put a regular mic right up against the wall. The smaller it is the better.
What made you decide to write The Audio Dictionary?
When I taught a course in Recording and Reproduction of Music at the University of Washington [it was] a very popular course. Lots of kids that were seriously interested in recording took the course. They were always asking questions about terminology. Most of the class time was spent answering questions. So I decided I'd copy some definitions and just hand it out to the class. I kept doing that and adding to it, and one of my students, Dane Butcher, (later founder of Symetrix) came into my office one day and he had all the handouts that I had been giving out, and he said, "Why don't you take all this and turn it into a book. You are like a walking audio encyclopedia. Why don't you put that down in a book — you'd get rich," and I said, "Well, I don't think I'll get rich." He said, "Well why not put out a book anyway?" So I thought about that. Naomi Pascal, the chief editor of the University of Washington Press was a friend of mine, so I called her up and I asked her, "Would you be interested in publishing a semi-technical, but fairly lengthy dictionary of terms in the audio business?" Her son also was a student of mine, so he was all for this of course, so she agreed to publish it. The first edition took me a long time, about five years. It was a lot more work than I thought. I wrote the whole book from memory, and then the hard part was going back and checking everything and making sure everything was correct. That was a big job. It has gone into two editions. I am working on the third edition. In all truthfulness, I think it's a pretty good book for what it is. It is not an encyclopedia, but hopefully it is written so that a person who is not a mathematician can understand it. There are very few formulas and equations in there. Everything is explained in plain English rather than math.
I found it easy to read. What was the weirdest definition to document for this book?
In the first edition I had "balls" in there, you know, like "Put some balls on the saxophone!" but I had a hard time defining it. How do you define that? [laughter] So I put that in the first edition, and the editors weren't too happy about that. But I said, "It's a term that is used a lot," so they acquiesced. I had to be kinda smart alecky about it so I said, "Unfortunately, there isn't any equivalent term of the feminine gender that compares with this." They didn't like that, so I took it out of the second edition.
How many clarifications and/or corrections did you have to make between the first and second editions?
Not a huge number between the first and second editions. Mostly additions to the second edition. The third edition will include more additions. The second edition came out before we had 5.1 sound, before we had this home movie [theater] sound craze. All that has to be described. That is a complicated subject all by itself.
How did you find the text by Charles Garnier from 1871 which you quoted in Appendix 4 ["Some Notes on Good Acoustics"]?
I took a course in French at the University [of Washington] and the French teacher said that the architect for the Paris Opera wrote a book about architecture and he has a chapter on Acoustics in there. And I said, "You've got to be kidding! Is the book still in print?" and she said, "Oh, no it's not, but you could find it in some archive someplace." So I asked who the author was and she told me and I went to the University Library and sure enough, they had it in their archives. You couldn't check it out because it was a rare book, but I could look at it. They had a copy machine there and I copied the chapter. It was in French and I didn't feel comfortable translating it, so I had a friend of mine translate it. I think it is an interesting quotation, and I think today's architects have almost the same problems that Garnier had
How is this is still relevant today?
Well Charles Garnier says that when he was going to build the Paris Opera he wanted to be sure that it had good acoustics, so he wanted to find out about good acoustics, and then he started to ask questions all over the place and began visiting concert halls all over Europe. He said that he found out from the Germans that you had to have a dome above the auditorium in order to make decent acoustics. And he found out from the English that you had to have a flat ceiling... and he said, putting all this stuff together, that none of that makes any difference. I just thought it was kind of a nice thing.
