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[Donald Copenbarger]

Virgin post after lurking for, well actually a couple years now on and off.

I need install a PA primarily for spoken word, but also occasional live band in a 45(L) x 39(W) rm with 8' ceilings.  Carpeted, 130 or so custioned seats, a couple large windows and maybe some hack-boy acoustic treatment (read whatever is soft, cheap, can be covered with material and absorbs something in the >2khz range).  I don't have RT60 or anything else as the room is not constructed yet, but with such a low cieling (sheetrock) my initial thought was a typical speaker on a stick (customer already has those.. CGM's with EV horns removed and placed on top to direct better) coupled with distributed (ie Tannoy cans).  Whilst I would assume decent coverage, the phase (meaning time not polarity) issues would be huge unless the FOH levels were so low that the cans were all you heard.  I guess the other option would be rear fills delayed or just the FOH.  Or what the heck, just the cans - that'd be interesting!  


*Edited to correct - actually I did post before, but forgot.

[Brad Weber]

Is the system run mono or stereo?  Is it 99% speech and 1% music or 75% speech and 25% music or what?  Which is the function that is actually the reason the system is there?  Do the bands make the money that allow for the speech applications or is speech the primary purpose and the bands are a side thing?  These would certainly affect which solution might be appropriate.

What type of band; a couple of people with acoustic guitars and vocals, hip-hop, heavy metal, jazz, string quartet, the USC Trojan Marching Band,...?  Might look at totally different solutions for one than for another.

Is the ceiling sheetrock for fire code or structural reasons and if so are any penetrations of the ceiling an issue?  Does the 45'x39' include the stage or is that outside this space?  Is this entire area audience?  Any columns, quite common in the type of room described, or other architectural elements that could block sound from the stage?  These practical issues could affect whether some type of fills are almost a requirement or even possible.

Is the audience standing or seated?  This can be a big difference with an 8' ceiling, especially if you might have people standing in front of the stage and then seated further back in the room.

Do you plan on using some type of DSP for the system?  Would you have multiple EQ, delay, etc. for mains and fills?  If not, then fills could be problematic.

Is there a budget?  Something like the Renkus-Heinz ICONYX might be a good technical solution but might also be outside the budget.

Not trying to make this overly difficult, but without this type of information my response has to be #5 "It Depends".

[Donald Copenbarger]

Wow - many q's.. I'll annotate for clarity:

Brad Weber wrote on Mon, 18 September 2006 16:14

Is the system run mono or stereo?  Is it 99% speech and 1% music or 75% speech and 25% music or what?

60% music / 40% speech. Currently mono, but have done both.

Quote:

Which is the function that is actually the reason the system is there?  Do the bands make the money that allow for the speech applications or is speech the primary purpose and the bands are a side thing?  These would certainly affect which solution might be appropriate.

Church with half of every service being music.  Include the special events and coffeeshop and I'd say about 60/40.  As far as verbal cues as to importance, however, it's 50/50 - both are critical.

Quote:

What type of band; a couple of people with acoustic guitars and vocals, hip-hop, heavy metal, jazz, string quartet, the USC Trojan Marching Band,...?  Might look at totally different solutions for one than for another.

The weekly service is bass (sometimes fretless/some elec), elec guitar, acoustic guitar, jimbe/conga or other hand perc, keys and 5 vocals.  The coffeeshop and special events range from solo acoustic to 5 piece rock.  Even had the Surfaris recently .  No rap is about the only constant, and you never know...

Quote:

Is the ceiling sheetrock for fire code or structural reasons and if so are any penetrations of the ceiling an issue?

Penetrations are not an issue.  Snake is currently run through a 9"x12" hole, for example.

Quote:

Does the 45'x39' include the stage or is that outside this space?

Stage dimension is ytbd - likely shoebox centered front, with an 8' cieling it will be at most 8" high.

Quote:

Is this entire area audience?

Yup.

Quote:

Any columns, quite common in the type of room described, or other architectural elements that could block sound from the stage?

None at present, though four may be required, though if you visualize the space they are not a consideration -  we're talking about 4 loli's painted white.

Quote:

These practical issues could affect whether some type of fills are almost a requirement or even possible. Is the audience standing or seated?  This can be a big difference with an 8' ceiling, especially if you might have people standing in front of the stage and then seated further back in the room.

Guess I'm not giving you much to go on here either - part of the time standing, part seated (seated for sermons, which I'm sure the congregation is thankful for).

Quote:

Do you plan on using some type of DSP for the system?  Would you have multiple EQ, delay, etc. for mains and fills?  If not, then fills could be problematic.

Four parametrics - just switched to mono a couple of weeks ago to free up an amp and eq (1mains/3mon).  DSP at most would be like a driverackPA (currently none req'd).

Quote:

Is there a budget?  Something like the Renkus-Heinz ICONYX might be a good technical solution but might also be outside the budget.

Have you done any jobs w/o one?  I'd like a piece of that.. I think around 2k max.

Quote:

Not trying to make this overly difficult, but without this type of information my response has to be #5 "It Depends".

Not at all.. I appreciate you taking the time.  Hope to hear back!

[Brad Weber]

"Tough" is an understatement!  Between the room, type of sources and budget, good design practice goes out the window as that eliminates every option.

The FOH only option may be the only practical approach with your budget.  This will certainly have many drawbacks as far as coverage (think blowing out those in front to get to the back) but it also might be the only way to get the frequency response, level and quality you probably want for the music applications while staying within the limited budget you have.  It's definitely the only option that would support any possibility of stereo operation without a much bigger budget.

The types and quantities of speakers, processing and amplification required to support the music styles you plan on having and to take any real advantage of the improvements in coverage possible with these other options would likely push any of those options well outside your budget, especially with the extra labor and wiring involved.

If this was primarily speech and maybe a few acoustic sets, the distributed only option might be better but that probably wouldn't work too well for all of your other applications.

[Rick Johnston]

Basically, you already have enough to do the job. There is no way you can put a concert sound system in a 45x39 room on a $2,000 budget. Or any budget in that room. That's a very small room. A set of unamplified drums is going to generate complaints that it's too loud.

IMO, you should take the "less is best" approach and focus on the voices. Let the band mix themselves acoustically on stage. After all, they play the same venue every week.

No instrument mics. No monitors (except for the one wedge that the solo singers will use).

Position the FOH speakers as high as you can. Focus them vertically on-axis to the seated listener in the
center of the rear of the room.

This problem won't be solved by sound system design. It will be solved if the musicians, singers, and techs work together.

Regards,
Rick Johnston

[Donald Copenbarger]

Great responses.. thanks!  I wasn't clear on what gear is already there, however -

They already have board,mains (the CGM's above),monitors,eq,comp,mics,etc.  They are basically knocking out some walls and making the space harder to cover and the question is where to direct the couple thousand they have?  I'm leaning toward a couple delayed in the rear, honestly, but I wanted to hear from some vets..

[Brad Weber]

Guess I didn't really account for their having an existing system and the funds being available solely for some type of augmentation.  I agree that some type of delayed fill would indeed be a logical first thought in that case.  It's still a good idea but with some issues to consider.

The 8' ceiling puts some constraints on any fills.  Anything surface mounted would have to be quite small to avoid being a headbanger, a potential ADA problem or simply where they get played with too much by the audience.  And with being only 3'-4' above people's ears you would need a number of fill speakers of any type in order to cover the area without there being large variances in level.

There is a perception that ceiling speakers are inappropriate for music.  Many are poorly suited to music reproduction of any quality but there are a number of them, such as some of Tannoys as you noted or the JBL Control 300 Series, that are quite acceptable for most fill and foreground applications.  You may be limited on how many of these types of speakers you could purchase within your budget after you also account for the delay, cabling and miscellaneous parts required.

Due to the room size and the fact that the stage will stick out, not much delay would be required for the fills, but some is probably desired for a couple of reasons.  One is that a person in the back corner of the room will probably be 50' or so from the mains and less than 10' from a fill, so delay is appropriate.  Second, it is nice to be able to delay the fills so that the sound from the mains arrives a little ahead of the sound from the fill in order to give some directional precedence to the stage.  If you have a stereo amp you might want to consider a 2 channel delay and setting up two delay zones.

So I think a ceiling speaker fill approach may be something to consider.  One possibility would be to feed the fills off a separate send from the console such as a mono out or a post-fade aux.  You could then control the level of the fills, maybe using the fills more and the mains at a lower level for speech applications and dropping the fill level and raising the mains for music.  Just a thought.

[Rick Johnston]

Donald Copenbarger wrote

A 45(L) x 39(W) rm with 8' ceilings.

We are talking 45 feet by 39 feet, right? Not meters? Eight foot ceilings, right?

Am I missing something?

A couple of speakers on stix placed pretty much anywhere will allow everyone in the audience to hear the spoken word -- and the singer. If you have an occasional band, use no mics and make them mix themselves acoustically.

I would not feel ethically comfortable proposing the sale of multiple arrays of delayed speakers in that room.

My computer model says four rows of speakers spaced at 10 feet with 9ms delay each. In a room that size? That's ridiculous.

Regards,
Rick Johnston

[Brad Weber]

Quote:

We are talking 45 feet by 39 feet, right? Not meters? Eight foot ceilings, right? Am I missing something? A couple of speakers on stix placed pretty much anywhere will allow everyone in the audience to hear the spoken word -- and the singer. If you have an occasional band, use no mics and make them mix themselves acoustically.

Level and intelligibility are two different things, yes you'll hear something, but you may not understand it.  If the main speakers could be located higher to where there was a direct path to every listener with little or no interference then this would not be an issue but I think the low ceiling prevents that from being possible.  For this application fills certainly may not be necessary, but then again they might be beneficial and I certainly do not think considering them is an ethical conflict or ridiculous.

I'm thinking of during a music performance, prayer, convocation, etc. that you have a bunch of 6' tall people standing up all over the room.  There will be very limited direct sound possible towards the rear of the room as a result of people standing between the listeners there and the speakers, most of what is received would be reflected, diffuse or reverberant.  Now add the additional issues of possibly having two sources in different locations if you have two speakers and a mono source such as speech.  Adding some direct sound in the back of the room, maybe two rows of ceiling speakers at the back of the room with delay adjusted to account for the path length difference and precedence, in order to increase the direct/reverberant energy ratio and intelligbility when those are critical seems to make some sense.

I have not modeled the room but if you have then try looking at STI or %ALCONS and coverage at maybe 5' above the floor with just the main speakers and a large number of 6' tall absorptive barriers to represent other people located between the speakers and the listener position.   I would expect the result to be much different than with no such barriers.

This is also one of those cases where the reverb time for the space will probably be low because of the number of people in a proportionally small volume, but all the absorption and diffusion will be on one plane causing a number of anomalies.  Using at least part of the $2,000 for some acoustical treatments that you can place once the system is in might also be worth considering.

[Donald Copenbarger]

Again, great responses.  I knew PSW was going to be an invaluable tool the first time I saw it.. I'm on a couple of newsgroups too, but the flames seem to obfuscate most real learning opportunities.

Brad - thanx for the info, I think you're right on track.  The rear fills could be placed out of harms way due to the seating arrangement, but I think Tannoy's or the 300's you suggested would be more cost effective, offer better intelligibility and be less obtrusive.  I really like the idea of directional precedence.. I probably would have timed it to the middle of the area covered by the fills, and with the distances we're talking minimal audible difference, but then again that little bit could change an odd effect into a pleasant one.  Also re: your later post, I haven't been able to afford real modeling software yet, but I will run ALCONS just to a/b the before / after (to pat myself, I guess).  I think I'm totally sold on two rows covering the middle to rear of the space, with a few panels once actual reflection surfaces are defined.  Thanks again.

Rick - I know what you mean, but I guess something is lost in the translation (mine, not yours).  If you heard & saw this room, and knew the goals and direction of this gathering I think you would see it a little differently.  No SR for music at all would be fine (and I have proposed that as an option for them) just using stage volume, but one of my goals for them is to experience them in working together from the monitor mix as it is new to them, b/c within a few years they will likely be moving to a much larger facility and have to rely upon it entirely.  Now it will be a much smoother transition for them, as they are already used to it, and to trusting and working with a sound guy.  Also the SR volume for this space (the way I set it) is so low, if you drop the house out completely you only notice that it sounds a little lifeless.  Bringing the mains up just at or above what comes directly from the stage gives the mixer a little ability to compensate if something (ie a particular vocal) is not cutting through cleanly, and an opportunity to train - for example how to sit a jazz guitar and keys in separate holes since they're all over the same frequencies when both are doing melody.  Right now they are in a wider & shorter area (less sq ft) and the SR has worked very well, but with the longer space I really believe some delay (less SPL than what arrives directly, and as Brad mentioned slightly later) is prudent.  I'm not trying to fleece the flock, believe me on that one.