In Ceiling Speaker Enclosure Help Needed ASAP

[Brazoo]

Say I am a total rookie to the whole world of home audio. I am trying to install some Polk (RC60i) speakers I purchased for a 6.1 surround sound and a few stereo speakers in my bar. Location of most speakers will be in the ceiling joists which are in my basement I am finishing. I will use batt r-19 insulation near the speakers. Around the box which obviously would not be blown in lose type.
My questions are as follows:

1. Should I make a homemade box out of 2X4's capped with a plywood top? The speakers I have measures 7.56 x 2.4 inches (diameter x depth) and I right now I can give about 5 1/4" in a box for them?
2. If I cap the box frame I am making should I port the box for better sound quality via hole in side or top of box? and if so how big of a port. The box will be about 12-16" length with depth of about 5 1/4" by about 15" width.
3. Should I even insulate the box in any fashion with expandable foam insulation or place some piece of the r-19 in the box?
4. Should I seal the corners of the box with silicone to make it air tight if I answer to #2 above is no to creating a whole in the box.

Thanks in advance for all your help from the Wisconsin Rookie.

Cheers - Brazoo

 

[TLS Guy]

Say I am a total rookie to the whole world of home audio. I am trying to install some Polk (RC60i) speakers I purchased for a 6.1 surround sound and a few stereo speakers in my bar. Location of most speakers will be in the ceiling joists which are in my basement I am finishing. I will use batt r-19 insulation near the speakers. Around the box which obviously would not be blown in lose type.
My questions are as follows:

1. Should I make a homemade box out of 2X4's capped with a plywood top? The speakers I have measures 7.56 x 2.4 inches (diameter x depth) and I right now I can give about 5 1/4" in a box for them?
2. If I cap the box frame I am making should I port the box for better sound quality via hole in side or top of box? and if so how big of a port. The box will be about 12-16" length with depth of about 5 1/4" by about 15" width.
3. Should I even insulate the box in any fashion with expandable foam insulation or place some piece of the r-19 in the box?
4. Should I seal the corners of the box with silicone to make it air tight if I answer to #2 above is no to creating a whole in the box.

Thanks in advance for all your help from the Wisconsin Rookie.

Cheers - Brazoo

Unless you know the Thiel/small parameters of the woofers of those speakers, and know how to design the optimal box, leave the space behind the speakers open. A speaker enclosed with the wrong box size sounds terrible.

 

[Brazoo]

The specs for the RC60i Speakers from Polk

This might help you help me having the specs of the speakers direct from Polk's website.

Driver Complement
Mid/Woofer 1 - 6-1/2" Diameter (16.51cm)
Dynamic Balance, mineral filled Polymer cone with rubber surround
Tweeter 1 - 3/4" Diameter (1.91cm)
Dynamic Balance, metalized soft dome in ball-and-socket swivel mount
Electrical
Overall Frequency Response 40Hz - 20kHz
Lower -3dB Limit 60Hz
Upper -3dB Limit 20kHz
Nominal Impedance 8 ohms
Recommended Amplifier Power 20 - 100 w/channel
Efficiency 89 dB
Dimensions
Overall Diameter 9"(22.86cm)
Cut-out Diameter 7-5/8"(19.37cm)
Mounting Depth
(assumes 1/2" [12.7mm] wall material) 2-3/8" (6.03cm)
Overall Depth 2-7/8" (7.30cm)

 

[TLS Guy]

This might help you help me having the specs of the speakers direct from Polk's website.

Driver Complement
Mid/Woofer 1 - 6-1/2" Diameter (16.51cm)
Dynamic Balance, mineral filled Polymer cone with rubber surround
Tweeter 1 - 3/4" Diameter (1.91cm)
Dynamic Balance, metalized soft dome in ball-and-socket swivel mount
Electrical
Overall Frequency Response 40Hz - 20kHz
Lower -3dB Limit 60Hz
Upper -3dB Limit 20kHz
Nominal Impedance 8 ohms
Recommended Amplifier Power 20 - 100 w/channel
Efficiency 89 dB
Dimensions
Overall Diameter 9"(22.86cm)
Cut-out Diameter 7-5/8"(19.37cm)
Mounting Depth
(assumes 1/2" [12.7mm] wall material) 2-3/8" (6.03cm)
Overall Depth 2-7/8" (7.30cm)

No help at all. They are not the Thiel/Small parameters.

 

[Brazoo]

Contacted Polk Support

Working on getting you what you need via Polk Tech support and will post shortly. Thanks TLS Guy for all your assistance.

Brazoo

 

[annunaki]

TLS Guy is correct. You need the T/S parameters for the woofer(s). If you do not have them leave them open. If you do not have access to the T/S parameters and still want to proceed, you can get the Dayton Woofer tester from parts express and get the actual measured T/S parameters. It is about $100.00 but is a great tool for any DIY enthusiast.

http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=390-804&CFID=1246541&CFTOKEN=64756293

 

[jcPanny]

In-ceiling speakers

Brazoo,
I wouldn't bother with a box for the entry level polk in-ceiling speakers. You should also consider the in-wall speakers for your Main L/C/R channels and a full 7.1 system. Your HT speakers will have a crossover with a sub to handle the bass. Consider some extra wiring so you can add a sub to the bar location also to improve the bass performance. I would also recommend a volume control for remote locations like the bar.

 

[TLS Guy]

I just went on the POLK website, and they say those woofers are designed for infinite baffle mounting. So leave them open to as much of the ceiling space as you can. If you box them in you will regret it.

 

[Brazoo]

"

jcPanny
In-ceiling speakers
Brazoo,
I wouldn't bother with a box for the entry level polk in-ceiling speakers. You should also consider the in-wall speakers for your Main L/C/R channels and a full 7.1 system. Your HT speakers will have a crossover with a sub to handle the bass. Consider some extra wiring so you can add a sub to the bar location also to improve the bass performance. I would also recommend a volume control for remote locations like the bar."

I agree with what you wrote on the vol control in the bar area which I am know planning. Here is what I am using for the front L & R in the system - Polk RC65i and in the front center channel I plan to use Polk Audio CSi3 Center Channel Speaker. All 3 rears will be the RCi60's in ceiling. I wanted to place one set in the left wall at a 90 degree to my couch but would not have a wall to do a 2nd on the right and with small kids under age 3 I was in no way going to have a floor tower they could pull over etc. So I opted for the 3 front and rears and will add a sub. Was considering the Polk Audio PSW404 10-Inch 200-Watt Powered Subwoofer, Black as my choice (yet to be purchased)

TLS Guy - Just got off the phone with Polk and like you said they are meant to be open and the specs are unpublished but he did tell me that if I did the enclosure or needed to that 1 1/2 ft of cu space total would be needed.

I am leaning to open based on all this and all your help. I will place a 2X4 on the side to keep the r-19 insulation off them but leave the tops open to the subfloor above.

Thanks to all for your help - Brazoo