Hello - I'm currently in a band and I've got a "unique" situation, I do believe. We've got a lot of bass-heavy sounds in the music; TR808 sample bass drops, quite a bit of bass presence. I've been considering looking into this new system for a little while, but I'm curious to know four things:

1 - I notice the average SPL you posted on another forum thread was around 105dB. Will adding more systems increase this? I'm not looking to play at 170dB and blow the back walls off the venue or anything, but 105dB falls short of even the minimum listed in the rider we use -- 115dB (A weighted) at FOH mix position without distortion or driving the system into clipping.

2 - The "subwoofer" boxes are indeed pretty small, judging by the pictures. Would 2-4 of these be able to accurately produce the bass drop of a TR808 hit? I mean, those things appear to my ears to fall down into the 5-20 Hz range near the end, and I wouldn't want to blow all my subs hitting one.

3 - Are you able to control the sound off-stage? I understand one of the points of the system is to allow the musicians more control of their sound. However, often times (and especially in small clubs), the musicians aren't aware of what it sounds like out front! Because you'll naturally be standing closer to your system than anyone else's, yours will more than likely be louder. If that's the case, I'd rather have someone at a "standard" FOH position dictating what needs to go up and what needs to go down.

4 - Finally, is room ambience a major problem with these units? Because they're listed as being able to provide the same coverage from the front of the room to the back, if we play in a very shallow-depth room, I can imagine the reverb bouncing off the walls and coming back at the stage, causing a slight delay to the sound. That's one of the major benefits of floor monitors; you want them to be louder than the sound that's being beamed back at you from the FOH stacks pointing at the back wall.

Sorry for the extremely long post... hopefully I can get some of these things cleared up!

Thanks -
- Will

I'll offer a bit of input here and ask Hilmar-at-Bose to fill in the rest of the details. He's a bass output master, I'm not.

1) Have you ever heard a band that is so loud that your ears start clipping (distorting)? I've heard this system do that to my ears so, my opinion is, it's loud enough for anyone.

2) I'll offer this, the system won't let you "blow" the bass modules. As for bass in the 5~20 range, I'll ask Hilmar to cover that.

3) The direct answer is yes, you can hand over your remotes to a sound operator ... but I don't recommend it. Let the musicians control the mix. We know how to do it, like when we play around a campfire. One of the benefits of the system is that there is no FOH. I think a key thing for folks to understand about this new approach is that this is not an ordinary loudspeaker. The falloff that you're accustomed to with a conventional loudspeaker is not there with a cylindrical radiator(tm) loudspeaker. Hilmar will you cover this as well?

4) Good question and the easiest answer I can provide is this, there is significantly less reverb than a conventional system. Consider this, monitors are perfect reverb makers. They are pointed at the ceiling and away from the audience. For the musician they are a nice way to be insulated from the FOH reverb, but that sound ends up in the room and the sound operator "covers" it with more volume on the PA. This continues (more monitor output followed by more FOH output) until you run out of headroom and then you're in a small room with a TON of SPL in the room and out come the ear plugs ... for the band and the audience.

Thanks for the post ... long posts are no problem. I hope that I answered some of your questions and that one of my colleagues will be able to fill in where I left some things out.

Steve

[This message was edited by Steve-at-Bose on Sun October 19 2003 at 03:38 PM.]

Let me try to answers point-by-point (amending what Steve just said)
1) SPL
That’s a pretty complicated topic and I’ll try to answer that more completely in a separate post later. In a nutshell: yes, you probably can get to an A-weighted 115 dB SPL in most venues. But it is certainly worthwhile to think about “why am I playing at a sound pressure level that is close to hurting my audience” and “is that really my artistic intent or just a side effect of my current equipment”.

2) Bass modules
Our bass modules are indeed very small (and lightweight) but they are designed to pack a full bass hit quite nicely. The system has ample protection, so you certainly can’t “blow” them no matter what you do. Most kick drums (and drum machine) actually don’t go particularly deep in frequency. Most of the “punch” refers to the mid-bass region. Very low frequencies (below 40Hz) tend to create “rumble”, and are rarely found in recorded music although they are occasionally used in movie sound tracks.
But that’s all very academic, in the end you have to try it and hear for yourself what it does.

3) Sound control off-stage
You say “the musicians aren't aware of what it sounds like out front” and that is the EXACTLY the problem we are trying to solve with this product. One of the fundamental properties of the Cylindrical Radiator™ loudspeaker is that it is NOT a lot louder on stage (close up) than in the audience. What you hear is what you get. Basically you, your fellow musicians, and the audience get the same mix. You can actually hear what everybody else is hearing.
I know, this is not intuitive and quite contrary to what you are used too, but it actually works. If anyone is interested I can get more into the technical details of why it works.

4) Reverb
As Steve has pointed out our system produces significantly less reverb then a conventional system, because it radiates little or no sound towards the ceiling and upper walls, which in most rooms are the main reflective surfaces responsible for reverberation.
In a sense what you are describing is a tug-of-war between Monitor and Front of the House. The front of the house needs to be loud enough to mask the sound coming off stage (monitors and back line) but the monitors have to be loud enough to mask the bleed from the main PA and room back onto the stage.
With the Personalized Amplification System™ family of products, that problem goes away. One system provides sound for everyone.
In our experiment we have never seen any significant problems with slap echo from the rear wall.

Hope that helps

Hilmar

[This message was edited by Hilmar-at-Bose on Sun October 19 2003 at 04:04 PM.]

Sorry if this thread is getting a bit "Bose heavy" but I want to add to what Steve said about "playing around the campfire" in answering the question "can musicians really mix themselves? (paraphrasing).

Not only do musicians mix themselves beautifully sitting around the campfire (we actually did this over the weekend: two guitars, an accordion, three singers and a recorder (!)), they do so in a living room, the kitchen, or the concert hall. A string quartet needs no one altering their sound. What we did in amplified music until now was the equivalent of letting someone hold the hand of the painter while he/she paints. Hard to create fine art that way. Interestingly, there is a point at which acoustic music needs a "FOH" person, and that's when the ensemble gets really big -- typically a symphonic group. There are so many musicians, and they're far enough apart on stage, that someone has to stitch them together acoustical. Of course the conductor is a musician of astonishing capability, not a FOB (friend of the band) and brings much more to the stage than simply stitching things together. The conductor is the chief artist.

We found in our musical-performance testing that artists that have played for years on triple systems (monitors, mains, backline) took almost NO TIME to learn how to mix themselves. They all play this way in their home and usually at rehearsal. It took very little in our tests for them to "let go" of the idea that someone else should be in charge of their sound, and to take control of their music again. They told us this was an incredibly liberating experience.

As to 115 dB-SPL A-weighted, I'll be stronger than Hilmar or Steve on this. YOU ARE HURTING YOUR AUDIENCE'S HEARING. This is a proven fact of science. What's worse, at that level, your audience can not hear very well because of huge amounts of distortion in their hearing system: you've dramatically exceeded the human hearing system's ability to do its thing. Excessive loudness was the number one complaint of audience members in our research.

Hey - Thanks for all the responses! I figured it'd take a bit longer. I'll address these comments individually as well, I suppose, for clarification.

1) Have you ever heard a band that is so loud that your ears start clipping (distorting)? I've heard this system do that to my ears so, my opinion is, it's loud enough for anyone.

In another thread on this forum, it was stated that the system was running about 100dB - 105dB. I wouldn't consider that a volume that would be clipping audience members' ears, personally, but I'm sure that it's all relative. I've been to shows recently where I have no idea what the SE was thinking blasting it so loud; while I agree that is uncomfortable and annoying, and definitely dangerous, it often seems that it's the mids and highs causing this -- not the lows. The problem I can see without being able to actually experience the system is that if you're playing in a smaller venue... let's say a rectangular building, 30'x40', with the stage in the center of one of the 30' sides... it doesn't seem like the bass from the 6.5" speakers (I believe that's the size, if I recall) would be enough to carry throughout that entire room. I've got some top-of-the-line Altec Lansing computer speakers on every system at home, and each one has an 8" sub... and while definitely not as efficient as your Bose system more than likely is, I know I wouldn't feel the kick drum if I lined two dozen of them up in a row!

In a nutshell: yes, you probably can get to an A-weighted 115 dB SPL in most venues. But it is certainly worthwhile to think about “why am I playing at a sound pressure level that is close to hurting my audience” and “is that really my artistic intent or just a side effect of my current equipment”.

I'd say that at least in my particular case, it's artistic intent. From the audience perspective, our crowd tends to be younger -- in the 17 to 25 range -- and when we play quieter shows (whether by virtue of club owners, noise ordinances, or simply a lack of a PA system and my refusal to compromise sound by running with the clip lights on), the crowd response shows a decidedly lower "enthusiasm" reaction, for lack of a better way to put it. On the other hand, when we play with some massive sub bins and a few kilowatts of Macrotech amplification behind them, the crowd response is typically a much more energetic thing.

From the musicians' perspective on stage, I can only give the opinions of my particular band of course... but we tend to play better when it's louder. Sure, acoustic shows are fun, and so are the lower-level volume ones. But nothing beats showing up with a few huge monitors and the bass rumbling off the back of the FOH bins... when you can literally feel the kick drum and the bass guitar. This is one reason we've hesitated to go with an "in-ear" system -- and if this Bose system does what I believe it's supposed to, we wouldn't need the in-ears anyway, which is a major reason I'm looking into them.

As for the rest of the comments, I've read them and they have helped my decision quite a bit. I like the fact that reverb has been dealt with (whether by accident or not!!) in the situation. There are two more comments I'm wondering if could be addressed, however:

1. I still don't understand how the system negates feedback. I was under the impression that the particular mic being used had more to do with the feedback response than the speakers themselves. A band on stage armed with a few Shure mics on stands typically has the microphones facing directly back towards them -- if the band members move, that puts a direct line of sight between the speaker and the microphone. Is the reason for no feedback simply the fact that the sound isn't blasting straight into them because it's omnidirectional (to an extent), or is there some other factor at play here? If I get the system loud enough (say, to the aforementioned 115dBA), does the chance of feedback skyrocket?

2. I noticed in your representations on the web site for the product that during the "before" pictures, the drummer's sound is displayed, while during the "after" pictures the drummer's sound is gone. We do play with a live drummer. I assume we'd have to set up the microphones like normal and just run them all into a submix to send to his L1 (more than likely two of them, one stage left and one stage right, to get a stereo pan). In our case specifically, our drummer plays quite loud. It's a single-bass Yamaha kit, and he plays them like he means it. I understand that having a drummer with better playing dynamics would result in a more pleasurable on-stage experience, but unfortunately that's not entirely a possibility. Would the L1 loudspeakers be loud enough on-stage to allow musicians standing fairly close to the drum kit to hear themselves? Often times in smaller clubs, you find that you're a bit closer to those crash cymbals and the toms than you'd like to be; I'd hate to have to go stand in the audience to hear myself!

Thanks again -
- Will

I'll cover just one thing quickly, I believe the "before and after" illustrations show the drums. I just looked at it and I see one Cylindrical Radiator(tm) loudspeaker per player. Sorry, maybe I'm looking in the wrong place. I count five players and five systems in the illustration with the roll-over. Anyway, yes, a drummer uses a system to project their sound into the audience.

I'll leave the rest for others to answer.

Steve

I'll take questions 1 and 2.

Question 1: Our new approach to amplification does not negate feedback. However; it is surprisingly insensitive to feedback. There are a couple of reasons.
One reason is that because of the way the Cylindrical Radiator™ loudspeaker maintains a relatively consistent sound pressure level as distance from the speaker increase versus a conventional loudspeaker which drops-off rather quickly as distance from the speaker increases. Here’s an example: Set the Cylindrical Radiator loudspeaker and a conventional loudspeaker to be the same level at 3 feet. Now walk back 30 feet. The conventional loudspeaker will be at 1/10 the intensity of the Cylindrical Radiator. Said another way, you would need 10X more power to get the conventional loudspeaker to the same intensity. This means that you have to play your conventional loudspeaker way louder to get the same experience at 30 feet. This greatly increases the chance of feedback – because you have to play the conventional speakers so much louder. Conversely, the Personalized Amplification System™ products don’t need to be played as loud in order to get the same intensity at 30 feet – less intensity, less feedback.

The other reason is that our new approach is much simpler (in a lot of ways). In general, you have one microphone and one speaker per musician or section – this is a minimal feedback system. Conventional approaches use multiple microphones mixed into multiple speakers (mains and multiple monitors). This becomes a very complex equation with lots of interaction between mics, mains, and monitors – this approach maximizes the opportunity for feedback.

And of course, it is the combination of these two reasons which enable the radical approach of putting the Cylindrical Radiator loudspeakers behind the musician. My 10 piece horn band (with lots of mics) has been using our new approach now for some time. We don’t spend anytime worrying about feedback – just playing and entertaining, it’s that simple.

Question 2: I don’t know your drummer, but I know my drummer used to play like “he meant it” as well. The reason for this is he wants to hear himself – a really reasonable request. Mix the drums thru a small mixer (we’ve found fewer mics to work better – 1 Kick, and 2 in the rack work great) and then put that mix into the Personalized Amplification System product. I’ve notice that our drummer plays with a lot more feel now – I know this is because he can hear himself and everybody else in the band. He still can pound it out. But the real win here is that he can also offer some contrast – he’s not always playing on 10. And because there is a 4 to compare it to, the 10 has some real context and meaning. The band loves it, the drummer loves it, and the audience loves it. We gave up nothing, and gained so much!

Excellent questions!

Thomas

Scotty said "I canna break the laws of physics Captain". So how do you explain getting around the Inverse Square Law for sound intensity?

"But Scotty, this speaker is not a point source! It obeys a different law of physics than a conventional speaker does!" You are right, a conventional speaker will obey the Inverse Square Law ... physics rule! The Cylidrical Radiator(tm) loudspeaker is not a point source and therefore it obeys a different law of physics. While this type of speaker has been proven to work in the lab and in audio theory textbooks, Bose spent 10 years researching ways to bring it to the real world and make it usable and useful for musicians.

For the non-geek-speak version of the physics, see Thomas' post in regards to SPL at 3ft vs 30ft for both types of speakers.

Steve (I love physics too) at Bose

[This message was edited by Steve-at-Bose on Tue October 21 2003 at 09:21 PM.]

Fascinating stuff... I understand that the theory is not neccessarily new; it has just never before been applied to the real world successfully.

You system is presumably based on Line Source theory (vs. Point Source) based on the stated benefits of much smaller SPL reduction with distance, and greater intelligibility through strictly limited vertical dispersion.

The real trick has always been how to get a line array configuration, with it's multiplicity of vertical stacked drivers, to behave as a "true" line source, in other words emitting a uniform cylindrical wavefront (vs. a spherical wavefront for conventional loudspeakers).

How did you address the acoustic coupling of the two dozen individual drivers in the array, or is that part confidential?

Also, based on the height of the radiator being seven feet (rather than infinite), at what distance from the speaker does the output waveform begin to behave more conventionally, and SPL drop of rapidly? (Assuming at a vocal frequency of, say, 1KHz)

Hey, I love physics too! Actually, I became interested in this concept when I heard a live Jazz performance this summer in the lobby of the Fountainbleau hotel on Miami Beach - I had never heard such a great sounding live vocal performance, and yet it took me several minutes to locate the speakers - finally, I saw them on 2 pillars; they were many feet tall, but only a couple of inches wide, and they were white so I didn't see them at first. I had tried walking around to locate the source of the sound, but it didn't change much, even when I was standing right in front of one speaker! I was amazed, and they sounded SO good! It was one of your speakers, I beleive, but not this new system? It was mounted on a pillar, and had no base assembly - it was also greater than seven feet tall.

Hello JazzMann,

Thanks for your questions. I've started a new thread called "Cylindrical Radiator speaker behavior" with a copy of your post and my reply there.

Hey Ken, I know you guys are busy (and thanks for taking the time to do this stuff), but you said you would start a new thread on this, for us "wannabie techies"? After hearing the system in action, I'm even more curious to know how it works!

Howdy,

We just got back from an incredible gig in Atlanta at the Guitar Center there. We did an invitation-only after hours show and it was the best audience yet. They laughed. They cried. It was unbelievable.

Anyway, we've written a few "white papers" on the research. They're non-mathematical but often technical. Anyone that wants a copy can mail me a request:

Ken Jacob
Chief Engineer
Bose Professional Systems
145 Pennsylvania Ave, MS 232
Framingham MA 01701.