Memo-Acoustical Treatment of the Pavilions Arena
-
II' -
.Memo
To:
From:
Honorable Mayor & City Council Members
Don Olson
Steve Mielke
Steve Stadler
Jay Strachota
August 21, 2003
Acoustical Treatment of the Pavilions Arena
cc:
Date:
Re:
.
After researching acoustical treatments and working with an acoustical engineer staff has
developed options to improve the quality of acoustics in the Pavilion arena. The options listed
are only recommendations and are not guaranteed to achieve a level of acoustics that would meet
the needs for every activity or event. However any treatments installed in the arena would
improve the quality of sound and be beneficial for all activities. The quantity of the treatments
listed in the options could be increased or decrease to fit any budget set for the acoustic project
and could also be combined with other treatments listed in other options. The options are listed
in range of costs and effectiveness. The total estimated cost for the purchase of acoustic surfaces
is $30,000- $70,000. The range of costs is due to the type and quantity of treatment possibly
needed. Attached is a proposal from one vendor and some of the information provided by the
acoustic engineer.
l'
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Option A: Rane:e$30,000-$40,000 for General-Purpose Acoustic Level
Option AI: K-13 Cellulose spray on the ceiling, end walls, bleacher soffit, and some patches
on sidewalls. Product would be similar to the treatment on the ceiling in the dance studio at
the Center for the Arts.
Ceiling and Bleacher Soffit,
End Walls '
Side Wall Patches
Additional Costs
Total
26,000 SF
3,000 SF
600 SF
$26,000
$3,000
$600
$2.000-$6.000
$32,000-$36,000
Option A2: PVC White Baffles installed between roof joists. Baffles would be staggered
between the joists hanging just below the .roof deck across the entire ceiling.
White Baffles (2'x 4'x I")
School Colored Baffles
Additional Costs
Total (Note: Deduct $5,500 if all the baffles are white)
1500
500
$12.60
$22.60
$18,900
$11,300
$4.000-$6.000
$34,000-$36,000
Option B: Rane:e $50,000-$70,000 for General-Purpose and a Road Show
Performance Acoustic Level
Option Bl: K-13 Cellulose spray, PVC Baffles, and Quilted Curtain
Cellulose Spray
PVC Baffles
Quilted Curtain
Additional Costs
Total
30,000 SF
1,000 Units
2800 SF
$32,000
$12,600
$12,880
$5.000-$8.000
$62,000-$66,000
.
Option B2: K-13 Cellulose Spray, Tectum Finale Panels installed on north and south wall
from 8' to 16' from floor, and Perforated Metal Panels installed from floor up to 8'.
Cellulose Spray
Tectum Finale
Perforated Metal Panels
Additional Costs
Total
30,000 SF
2,000 SF
1,700 SF
$32,000
$9,000
$13,600
$4.000-$6.000
$58,000-$61,000
Option C: No Action Option
Under the No Action Option staff would study potential revenue sources to offset the cost of the
project and/or create additional operating revenue. We now know the costs of improvements but
have not yet had a discussion around revenue expectations due to the improvements.
.
Acoustical Surfaces, Inc.
SOUNDPROOFING, ACOUSTICS, NOISE & VIBRATION CONTROL SPECIALISTS
-
.
123 Columbia Court North · Suite 201 · Chaska, MN 55318
(952) 448-5300 · Fax (952) 448-2613 · (800) 448-0121
Email: info@acousticalsurfaces.com
Visit our Website: www.acousticalsurfaces.com
We Identify and S.T.D.P. Your Noise Probl ms
Fax Transmission to Follow
--y.... Pages (includes cover page)
To:
Attn:
City of Hopkins
Don Olson Re: Ice Pavillion Acoustic Panels
Keith Johnson t;. J.. 3.0;'
From:
Remarks:
After evaluating the numbers I suggest one of the following:
quote #1_: 2000 hanging PVC 2'X4/X1" Baffles will drop the reverb time in the room
from 5.2 seconds(with turf)7.26 seconds with ice - all the way down to 1.39 seconds
This would bring speach intelligibility levels from 1 in the untreated space to 61 in
the treated space. Cable/hooks through eyelets -simple installation. School colors or
white available. Ask for installation quote from Minnetonka Sound if needed. See
graphs.
Quote 2 would have quilted curtain material around the boards at one end of the rink
and 20 foot long curtain panels that would drop from a cable/hook system from the
ceiling across the far blue line. This alone would get you to a 3.92 reverb time so you
would need 1000 hanging baffles in addition to get to the 1.39 second time from
above. This is a more expensive approach with the same acoustical results and
would make you hang the panels over the ice the opposite direction during Ice
season. More labor intensive but would give you a more performance venue look
during the non ice season.. .
We can include an installation'quote if needed through Minnetonka Sound.
Samples sent - Call with questions/ order.
.
· Soundproofing Products - Sonex" Ceiling & Wall Panels - Sound Control Curtains - Equipment Enclosures · Acoustical Baffles & Banners · Solid Wood & Veneer Acoustical Ceiling & Wall
Systems - Professional Audio Acoustics · Vibration & Damping Control · Fire Retardant Acoustics - Hearing Protection · Moisture & Impact Resistant Products . Floor Impact Noise Reduction .
Sound Absorbers · NOise Barriers .l!fao/iotla~Mll"I!PtdbWm.IS'<re(/t'Whtg thisJ&~plJal_&edlJ!ftlk( 61~)d44f:Mj3.00-111 - Assistive Listening Devices . OSHA,
FDA, ADA Compliance · On-Site Acoustical Analysis · ACOlfstical DeSign & Consulting . Large Inventory · ~ast Shipment · No Project too Large or Small . Major Credit Cards Accepted .
Architectural Surfaces, Inc
123 CblumbiaCourt North · Chaska, MN 55318
(952) 448-5300 · FAX (952) 448-2613
Order Acknowledgment
Salesperson:
Date:
A
S
I
/
Sold To:
City of Hopkins Don Olson
PavilliOll 11000 Excelsior Blvd
Hopkins,Mn 55343
952-939-1411 Fax 979-0446
Ship To:
Kei th Johnson
5/23/03
.
PO#
Requested Ship date
ASI Delivery Schedule weeks from
receipt of signed and retruned Acknowledgment.
Thank you for your order. This is the acknowledgment and sales contract for the order you have
placed with Architectual Surfaces, Inc. Please verify quantities, description, price and shipping.
Notify us immediately if incorrect. All shipments are FOB plant and shipped freight collect or 3rd
party billed as requested. Freight is not allowed or prepaid unless indicat~d below. Resale sales tax
exemptions certificates must be supplied or sales tax will be charged.
Bill Freight To:
Sh' V'
FOB
o PPD & Add 0 C 11 ct 0 3 d Party
IP la o e r
Quantity Item No. Description Unit Price Unit Fxtensinn
~..
2000 2'X4'X1" Hanging PVCBaffles 22.60 45,200.00 f
School Colors oil-
or
2000 PVC"White Sak Baffles 2'X4'X1" 12.60 25,200.00 .
f
ASI DOES NOT GUARANTEE QUANTITIES NEEDED OR TAKE OFFS.
Please sign and return this order acknowledgment ASAP!!
Production of your order is scheduled but cannot begin until we have
received a signed copy and deposit if noted. Discounts, charge backs,
debits, or retainers are not allowed unless specifically authorized in
writing by AS!. Freight damage or shortages must be reported to carrier
on receipt. Past due invoices are subject to a 1.5% per month finance charge.
Liens will be filed on all past due invoices.
SALES ARE SUBJECT TO THE CONDITIONS OF SALE LISTED ON
THIS ACKNOWLEDGMENT HEREOF.
I
Accepted By X
Deposit Due with this order
Date
\:t.A
~i;j
~>"1
~?
.Co:]
):'~~
~' ~'\
Freight Estimate
Sales Tax
Total
Deposi t Recv'd
Balance Due
Terms
Please send: 0 Credit Application
o Tax Status
.
A
S
I
Architectural Surfaces, Inc
123 Columbia Court North · Chaska, MN 55318
(952) 448-5300 · FAX (952) 448-2613
Order Acknowledgment
Salesperson:
Date:
Ship To:
Keith Johnson
5/23/03
'.
.
/
Sold To:
City of Hopkins Don Olson
Pavillion 11000 Excelsior Blvd
Hopkins,Mn 55343
952-939-1411 Fax 979-0446
PO#
Requested Ship date
AS! Delivery Schedule weeks from
receipt of signed and retruned Acknowledgment.
Thank you for your order. This is the acknowledgment and sales contract for the order you have
placed with Architectual Surfaces, Inc. Please verify quantities, description, price and shipping.
Notify UR immediately if incorrect. All shipments are FOB plant and shipped freight collect or 3rd
party billed as requested. Freight is not allowed or prepaid unless indicated below. Resale sales tax
exemptions certificates must be supplied or sales tax will be charged.
Ship Via FOB 0 PPD & Add 0 Collect 0 3rd Party
Bill Freight To:
Quantity Item No. "De.<nipti011 Unit Price Unit ExtenRion
2800 Sq ftQuilted Curtain QFA-1 4.60 12,880.00
or
1000 PVC PVc Baffies2'X4'X1" 22.60 22,600.00
/ School Colors
,
ASI DOES NOT GUARANTEE QUANTITIES NEEDED OR TAKE OFFS.
Please sign and return this order acknowledgment ASAP!!
Production of your order is scheduled but cannot begin until we have
received a signed copy and deposit if noted. Discounts, charge backs,
debits, or retainers are not allowed unless specifically authorized in
writing by AS!. Freight damage or shortages must be reported to carrier
on receipt. Past due invoices are subject to a 1.5% per month finance charge.
Liens will be filed on all past due invoices.
SALES ARE SUBJECT TO THE CONDITIONS OF SALE LISTED ON
THIS ACKNOWLEDGMENT HEREOF.
Freight Estimate
Sales Tax
Total
Deposit Recv'd
Balance Due
$0.00
$35480.00
$35480.00
Terms
Accepted By X
tieposit Due with this order
Date
Please send: 0 Credit Application
o Tax Status
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, ; ,t.s AQd Sur-face... I t:rt EdiL, k,r:::; Re:ml;)'ve I:
Total,Absorption' , ' Speech Intelligibility ,
1 9665 :Sabins : 1 l' ~/o, "
Space " '
, "Mame }opki~s ~:~a ~',
, "Volume' ,
, : ,- ,. , 77~00 I :G11 ~u ~t'"
Background NOIse, bevel,
',I ' " .45.J'dB'
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W~rk5h~et - Existing Space'
'Surface 'Ma'terial
Ceding Metal Deck
Floor Carpet glue direct. 1/8" Pile height
North Wall Concrete Block painted
East Wall Concrete Block painted
South Wall Concrete Block painted
West Wall Concrete Block painted
Misc. Air@72 F /1000 cu It@40RH
Misc. mise
Misc. qc
'Reverberation Time
, , ,
1 ' 1 3.92 :; Seconds "
,,'
~peaker Qistan~e'
I, 1~ t:r~t'
, Area s It
25,800.00
25,800.00
6,450.00
3,600.00
6,450.00
3,600.00
774.00
300.00
2.800.00
Noise Reduction
, L_______.__ .__~~/, ~;,J.__, ___, __nO, __L:J,,", ':
Reverberation'Time ' " , ' , , ' ,
Voice Level
1 ~IE ,f\J()rmal , i :'"
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T olal Sabins
2580 I,'
2580
387
216
397
216
619
300
2380
I,
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Absorption Required
Qesired Reverb7r!3tion Time '",
L ,__ _ ..!;~~f Seconds
30341 ;' Sabins
,
0,.00, :' Seconds " ,
0, .00 ~' dB Reduction
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~a~e IHOP~~S Arena , . ,
~olume . " ' Background 'Noise leve"
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Acoustical S~~ce$lnc .',
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- Speaker Q,istance ,
1~__l:J ~t .
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Voice Level
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~I1(Rai~ed 'I "
Worksheet -: Existing Space
Surface,
Ceiling
Floor
North Wall
East Wall
South Wall
West Wall
Misc.
Misc.
Malerial
Metal Deck
Concrete or T err azzo
Concrete B lock painted
Concrete Block painted
Concrete B lock painted
Concrete Block painted
Air@72F/1000cuft@40RH
mise
, Area s It
25.800.00
25,800.00
6,450.00
3,600.00
6,450.00
3,600.00
774.00
300.00
Total Sabins '.
2580
516
387
216
387
216
619
300
vJ 1-\1- S Ce..~.
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,
, Reverberation TIme
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-'I :7.26 Second~'
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Total Absorption, Speech Intellig!bility
,I 5221 ' iabins', I . 1 ~/o' .,'
5.76 ,: Se~onds 'I
6.84 , dB Reduction
~bsorption Required
Qesired Reverberation Time
L_______~}S! Seconds
'30341: Sabins
No~se Reducti.on '
I~.:!~~~ S~ace . ...J:Ji '-> I~~e~~~.?pa~_~ _ _ .8 .
aeverberation Time
.
Hopkins Arena
Noise Reduction Report
5/21/2003
Contact :
Location :
Phone
Volume of Space:
Background Noise:
774,000.00 Cu Ft
45 dB dBA
Voice Level:
Distance from Speaker:
.
Normal
18 ft
Existing Space Area (sq ft) Abs Coeff
Surfaces Material Dimensions or Quantity @ 500Hz Total Sabins
Ceiling Metal Deck 215.0 X120.0 25,800.00 0.10 2580
Floor Astro turf 215.0 X120.0 25,800.00 0.10 2580
North Wall Concrete Block painted 30.0 X215.0 6,450.00 0.06 387
East Wall Concrete Block painted 30.0 X120.0 3,600.00 0.06 216
South Wall Concrete Block painted 30.0 X215.0 6,450.00 0.06 387
West Wall Concrete Block painted 30.0 X120.0 3,600.00 0.06 216
Misc. Air @ 72 F / 1000 cu ft @ 40 RH 774.00 0.8 919
Misc. mise 300.00 1. 0 300
Total Absorption (Sabins) 7285 Estimated Reverberation Ti e
Treated Space 1 Area(sq ft) Abs Coeff
Surfaces Material Dimensions or Quantity @ 500Hz Total Sabins
Ceiling Metal Deck 215.0 X120.0 25,800.00 0.10 2580
Floor Astro turf 215.0 X120.0 25,800.00 0.10 2580
North Wall Concrete Block painted 30.0 X215.0 6,450.00 0.06 387
East Wall Concrete Block painted 30.0 X120.0 3,600.00 0.06 216
South Wall Concrete Block painted 30.0 X215.0 6,450.00 0.06 387
West Wall Concrete Block painted 30.0 X120.0 3,600.00 0.06 216
Misc. Air @ 72 F / 1000 cu ft @ 40 RH 774.00 0.80 20919
Misc. mise 300.00 1.00 300
'.
Misc. * Fiberglass Baffles 2'X4'X1" 2,000.00 10.00 20
Total Absorption (Sabins) 27285 Estimated Reverberation Ti e
Impr vement Over Existing Space
Change in Reverberation Time: 3.82 Seconds Noise Reduction:
f,>(\ S-+ l~
. u-J\-\-~ r
IlJ {L-'(
.
.
1IlAJ..1 <e ~<J5?
Reve~
, 80
"0 70
o
.s 60
Ul
Qj 50
"0
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5l 30
~ 20
Q)
c.. 10
o
7
6
Ul
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~4
en -
.53
Q)
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l-
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Existing Space
v.h~-"" i v {t'"\
Treated Space 1
Ul
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u
~ 4-
c:
'Qj 3
E
i=2
1
250Hz
6
,
500Hz 1kHz
Frequency
2kHz
Speech Intelligibility
Existing Space
III Existing Space
~ Treated Space 1
Treated Space 1
Acoustical Surfaces, Inc.
Soundproofing, Acoustics, Noise & Vibration Control Specialists
123 Columbia Court North · Suite 201 · Chaska, MN 55318
(952) 448-5300 · Fax (952) 448-2613 · (800) 448-0121
Email: sales@acousticalsurfaces.com
Visit our Website: www.acousticalsurfaces.com
.
We Identify and S.T.O.P. Your Noise Problems
'"
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POLY VtrRAP.
HANGING PERFORMANCE BAFFLES
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~<I Lowest Cost
~ Ughtweight
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MATERIAL: Poly Chloride Film encapsulated Fiberglass.
PATTERN: Plain - with Z grommets/baffle.
FEATURES: Economical, Multi-Purpose, High Performance, Lightweight.
APPLICATIONS: Gymnasiums, Auditoriums, Arenas & Stadiums, Manufacturing Plants, Machine Enclosures,
Water Treatment Plants, Animal Hospitals and Swimming Pools.
THICKNESS: 1/2" SIZES: 2'x4', Custom sizes also available WEIGHT: 21bs each
COLOR: White, Black (Other colors available upon request) .
FLAMMABILITY: ASTM E84, Class A. Flame Spread: 8; Smoke Developed:O
Poly wrap B.A.P.
Baffle: Sabms/Baffle
1 1/2"
125Hz
2.1
250Hz 500Hz 1 KHz 2KHz 4KHz
6.5 10.7 14.1 12.7 8.1
NRC Ire . BV .
11.0
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13.00
12.00
11.00
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. SoundprOOfing Products. SonexTM Ceiling & Wall Panels' Sound Control Curtains' Equipment Enclosures' Acoustical Baffles & Banners. Solid Wood & Veneer .
Acoustical Ceiling & Wall Systems. Professional Audio Acoustics' Vibration & Damping Control. Fire Retardant Aroustics . Hearing Protection. Moisture & Impact
Resistant Products. Floor Impact Noise Reduction' Sound Absorbers' Noise Barriers' Fabric Wrapped Wall Panels' Acoustical Foam (Egg Crate) . Acoustical Sealants &
AdheSives. Outdoor Noise Control' Asslstive Listening Devices' OSHA, FDA. ADA Compliance' On-Site Acoustical Analysis' Aroustical Design & Consulting' Large
Inventory' Fast Shipment. No Project too Large or Small. Major Credit Cards Accepted
.
Acoustical Surfaces, Inc.
Soundproofing, Acoustics, Noise & Vibration Control Specialists
123 Columbia Court North · Suite 201 · Chaska, MN 55318
(952) 448-5300 · Fax (952) 4:48-2613 · (800) 448-0121
Email: sales@acousticalsurfaces.com
Visit our Website: www.acousticalsurfaces.com
We Identify and S.T.D.P. Your Noise Problems
QU~l:rED CU'RTAIN S.T.O.P.
AbsorptiveJNoise Barrier Quilted Curtains
~' For Unusual Conditions
~ Cost Effective
~l Water & Chemical Resistant
.., Exterior Applications
MATERIAL: Foam or fiberglass core, faced with quilted aluminized fabric.
PATTERN: Quilted pattern
FEATURES: Effective and durable absorber with mass loaded vinyl barrier option.
APPLICATIONS: Effective solution to a wide range of unusual problems. Machinery and work area enclosures
THICKNESS: 1" & 2" SIZES: 48" - 54" Wide; Lengths up to 25' - Custom sizes available
COLOR: Silver (Other colors available upon request)
FLAMMABILITY: ASTM E84, Class A. Flame Spread: 23, Smoke Developed: 30.
INSTALLATION: Hook and loop fasteners, grommet hangers, curtain support hardware.
-
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QUILTED CURTAIN S.T.a.p. Sound Transmission Loss -ASTM E90
126Hz
11
13
260Hz
16
20
600Hz
24
29
1KHz
30
40
2KHz
10
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15 27
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125
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QUILTED CURTAIN S.T.O.P. Sound Absorption Coefficients - C423
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2000
4KHz NRC
0,62 0.70
0.99 0.85
126Hz
0.12
0.07
260Hz
0.47
0.27
500Hz
0.85
0.96
1KHz
0.84
1.13
2KHz
0.64
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.
. Soundproofing Products. SonexTM Cellmg & Wall Panels' Sound Control Curtains' Equipment Enclosures. Acousbcal Baffles & Banners. Solid Wood & Veneer
Acouslical Ceiling & Wall Systems. Professional Audio Acoustics. Vibration & Damping Control' Fire Retardant Acoustics . Heanng Protection. Moisture & Impact
Resistant Products. Fioor Impact Noise Reduction. Sound Absorbers. Noise Bamers . Fabnc Wrapped Wall Panels' Acoustical Foam (Egg Crate) . Acoustical Sealants &
Adhesives' Outdoor Noise Control' AsslstlVe Listening Devices. OSHA. FDA, ADA Compliance' On-Site Acoustical AnalysIs. Acoustical Design & Consulting' Large
Inventory' Fast Shipment. No Project too Large or Small. Major Credit Cards Accepted
~8/18/2003 09:11
9529341300
WM H 0 KROLL & ASSOC
((
~
I
Wm. H. O. Kroll & Associates, Inc.
Engineers Consulting In Acoustics
5217 West Mill Rood · Mlnnetonko. Mlnnesoto 55345
PhOl'l0 952.934.9494 · FAX 952.934.1300
15 August, 2003
The Hopkins Pavilion,
11 00 Excelsior Blvd.
Hopkins, MN 55343
Fax 952-979-0446
For Mr. Don Olson R Pavilion Manager
, Subject:
P/itvilion Acoustics
Dear Sir:
This writing follows our report of 6 August, 2003 and your writing of 7
August, 2003 with specific questions.
Beginning with Article 1 of your letter: Having already worked on well over
1,000 projects in some thirty states from New York to California,. 1 can tell
you that I am not aware of any standards with respect to acoustical
characteristics for pavilions such as yours. No, not even for Auditoria except
that they are critiqued by reviewers and listeners at a performance as having
good or poor acoustics.
True, I have my own personal standards and know what famous music halls
have in terms of acoustical characteristics. Remember at my first visit to the
Pavilion, I asked, "Shall it be good for music, sports happenings, meetings,
banquets, flea markets and so forth?" I left with the understanding that it
should be acceptable for music by road show-type music groups to perform -
from a platform near the South blue line. I think I told you, at the time, that
it would hardly be practical to make it good for serious music because the
remodeling at the ceiling, side walls, stage and end walls would - to make it
good for music - not allow for it to be good for sports happenings.
I did say then that there was no reason why it could not be made to work
and practically so for road show groups with big loudspeakers. This is so
because with electro~iC? bands with powerful amplifiers and loudspeakers, the
PAGE 02
,. '
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.
'08/18/2003 09: 11
9529341300
WM H 0 KROLL & ASSOC
PAGE 03
.
2.
pavilion could be made to work with a few simple changes to walls and the
ceiling which could, at the same time, make it better for hockey games and
the like. My whole set of recommendations is based upon this last theme
and it should work well, if done in keeping with the recommendations set
forth in my 6 August letter.
The above should explain the recommendations and tell you that I, in my
opinion as a legally practicing engineer with a specialty in acoustics - sound,
. noise and vibration - can tell you, based upon my experience on hundreds of
such projects; that what is recommended will give you the acoustical
improvements that you are looking for.
As requested in your Article 2 - the square footage for each area:
The whole ceiling, a forty foot long band of treatment along each side wall
where the area is accessible and the end walls plus the soffit area over the
bleacher; if covered with a one inch thick sprayed-on K-13 cellulose spray
would sum to
Ceiling
40 foot patches
End walls
25,800 square foot
560 square foot
3,080 square foot
,
Music played in the center of a football field never sounds as good as music
played in a concert hall but why not? A sound in the center of a field with
no walls or ceiling to reflect from goes on out to the moon, as they say.
Now in a concert hall, the walls and ceiling reflect sounds, good or bad to a
listener sitting in the seating area of such a hall. In a hall with good
acoustics, the sounds are reflected from the walls and ceiling in good order
so that all sounds strike the human ear within about twenty thousandths of a
second of each other. That is what pleases the human ear. Sound that
strikes the ear with separations of fifty or more thousandths of a second are
heard as annoying echoes. A free lesson in acoustics and now all can see
how really complicated it is to design a music hall for good acoustics. Please
see Fig. ONE, sent along with this letter and see the echoes ("bumps") in
the low part of the grid.
I should explain: By music, I mean live music as from an orchestra, choir,
high school band, guitar concert and so forth. This is to be differentiated
from road show-type music with electronic guitars and thousand watt power
amplifiers with powerful loudspeakers. For road show-type concerts, all the
music is electronically processed and played really loud so that acoustical
deficiencies in a space have a lesser negative effect.
.
08/18/2003 09:11
9529341300
WM H 0 KROLL & ASSOC
PAGE 04
" ..
3.
So with the two kinds of music in mind, what is recommended here is for
road show-type music which Comes with its own loudspeakers. The space
would be quite good though for the other ,kinds of music, too without
electronio sound processing but a concert hall it will never be. To say it
again: The big remodeling of ceiling and side walls to make a concert hall
out of it would not be good for hockey or the like. A reasonable compromise
could be possible and a good thing.
As to Article 3:
If you were to spray the ceiling and recommended wall parts with the K-13,
you would take care of about 60% of the complaints about acoustics in the
Pavilion. To add the Tectum "Finale" panels would bring the "satisfaction
level" up to 75% and to add the perforated metal panels would bring the
Pavilion up to nearly 90% as a satisfaction rating.
To keep in mind for those not familiar with the three materials listed above.
A. The K-13 cellulose spray at one inch thick is low in cost and utterly
functional in terms of sound absorption but it is a soft material and easily
damaged by picky fingers.
8, The Tectum IIFinale" is good at sound absorption and quite tough. If you
hit it with your fist, you will end up with a bloody fist but It can be scratched
Into with metal things.
c. The third material - that of perforated metal panels - are plastic film
wrapped fiberglass in a tough perforated sheet metal protective cover.
For Article 4. Cost - please consider the following:
The K-' 3 spray about $30,000.
The areas of Tectum "Finale" - about $9,000.
The band of perforated metal from the eight foot level on down to about 1 8
inches off the floor $13,440,00
It is important to keep in mind that the above areas are for the whole ceiling
area but otherwise only for the south wall and the west wall for a forty foot
long band and at the north wall, all wall areas that are not glass and a K-13
spray on the face of the soffit over the bleachers. Also, all who read this
should keep in mind that mine is not an estimating firm but rather, an
engineering firm that speoializes in acoustics - sound, noise and vibration.
The cost estimates set forth above stem from the known areas
recommended to be treated and installed cost estimates from those who sell
.
.
.
'08/18/2003 09:11
9529341300
WM H 0 KROLL & ASSOC
PAGE 05
4.
the products. Thus, the cost estimates for the minimum wall and ceiling
treatment recommended total to an estimated $52,000.
More to go on with ceiling clouds and angled side wall panels would cost
from $18,600. For a simple cloud over the performance area as a minimum
effort and this could go on to angle side wall wings at about $21,000. On up
to a complete ceiling cloud system at about $220,000.
You should keep in mind that everything said in this report is based upon
acoustical considerations only and we do not pretend to advise on structural,
architectural, electrical, mechanical, fire, health or safety things. Those
qualified in those fields should rule on their respective areas of competence.
Please call if questions arise.
Very truly yours,
~ (/3//1)
Wm. H. O. Kroll, P.E.
WmK/iw
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