How sealed should a sealed enclosure be?

[thomo57]

I picked up a pair of speakers with Coral 10 CX-50 in them.
I found a thread on a sealed enclosure and a ported enclosure for them.
These are in a sealed enclosure but to my eyes they aren't really sealed.
I haven't checked the seal between the speaker and face plate but the back is only held in place with 4 screws and there is a fairly large hole (half inch) which the speaker wire goes through.
There is also no form of deadening in the enclosure.

2 Questions
1: Would these benefit from ensuring the enclosure is very well sealed

2: Would they also benefit from some sort of deadening in the enclosure

I will post photos later or I do have another thread on them with photos

 

[thomo57]

http://www.audiokarma.org/forums/showthread.php?t=674187

 

[ChrisNC]

I don't know the speaker, but I would say they should be sealed. You could try something like foam weatherstripping that has adhesive on one side to go around the back. You might be able to do the same for the driver as well if it isn't sealed. I would also plug that hole - perhaps with something like Blu-tac. (It is hard to tell from the pictures how well the front is sealed, but it might need some attention too.)

I would assume they would benefit from some fiberglass insulation or something similar. You could experiment with the amount.

 

[thomo57]

I've used a product called earth wool from Bunnings
Covering all sides inside except the front panel.
Sealed the internal edges with a water based silicone.
Sealed the speaker driver edge and sealed the rear panel with padded tape

I'll have to wait until the wife's not in the house to really audition them .
I don't have 20 20 hearing:scratch2: but first impression is that they sound superb.
I'll have to move them around to find the sweet spot.

 

[nfafan]

They are not that far removed from this notion where so much of the cabinet is open, two "slotted ports" one above and below the driver, plus a small hole out the back panel where the wires attach to a connector block...

http://www.audiokarma.org/forums/showthread.php?t=667170&highlight=electro

 

[thomo57]

They are not that far removed from this notion where so much of the cabinet is open, two "slotted ports" one above and below the driver, plus a small hole out the back panel where the wires attach to a connector block...

http://www.audiokarma.org/forums/showthread.php?t=667170&highlight=electro

Are those open ports top and bottom?

 

[Porkloin]

Sealing

It may be a bit pricey - isn't that all relative? - but you may be able to kill two birds with one stone with Acoust-X. Fill that big speaker wire hole with an actual terminal plate and if it doesn't have a gasket with it, make the effort to make one from that closed cell foam lining the tool box drawers. That same foam makes great speaker gaskets and cuts easily with kitchen shears - the thick bladed clunky ones you get at the discount store. 1/8" closed cell foam is also pretty cheap if you live in a metropolitan area rife with foam stores.
Avoid gluing drivers down with silicone as there may come a day that you'll regret it as you're tearing away half of your cabinet while removing a woofer. Apply ANY silicone you use last as it's a repellent to all other coatings, such as the abovementioned Acoust-X.

 

[nfafan]

Are those open ports top and bottom?

Yes, rectangular shaped "ports" - slots - above and below the centered driver.

I ended up putting a very loose hand-full of poly-fill from a cheap WalMart bed pillow in the "upper slot", and a piece from a sheet of foam WalMart "mattress topper" up and around the one interior side.
It was simply stuffed in place loosely and "holds itself" in place..

This no-name furniture-grade cabinet looks professionally done and has an opening to use a 15" driver with captive bolts, and has with a "downsize" plate that mounts the 12" E-V 12TRXB tri-ax in the center of the 15" opening.

Wish I had a tube receiver to complete the 60's aura...

 

[thomo57]

I have a mate who is a shop fitter and has all the gear and skills to make some open ported speakers like you've posted.
The cabinets these Corals come in were made as a sealed unit but weren't properly finished as far as sealing and damping.
Which I have now done
Do you think I could benefit from getting ported speakers built or is this a case of the unknown.

 

[thomo57]

Here are some details on this speaker which for someone that doesn't know how to evaluate them :scratch2:
The details here seem to indicate a bass reflex speaker.
CORAL 10CX-50

25cm2 way coaxial type speaker unit obtained the highest rating at Coral Golden 50 series.

25cm has become a combination of a structure in which a cone type woofer and the horn type tweeter.

The edge of the woofer I have adopted a sky bar edge.
This is a variant of the free edge, in foreign countries has been used as a roll surround edge.

The magnetic circuit has adopted the Paul yoke using NKS magnet and high-purity iron, with the aim of higher efficiency.
The voice coil has adopted the long travel type, even in a large amplitude and has prevented the disengaging voice coil from the next time.

The diaphragm of the tweeter I have adopted a duralumin diaphragm of 20 microns thickness.
In addition, it is possible to adopt an aluminum edge-wise voice coil to the voice coil, and has adopted a new bond-type magnetic circuit for level-up of tweeter.

The horn part I has adopted the die-cast horn straight direction type.
In addition, we have to adjust the phase shift of the sound from the diaphragm by tweeter equalizer.

To frame part we have adopted the prominent frame.
This frame structure has the effect of suppressing the unwanted distortion when you mount the cabinet.

It has a built-in network.

There was 10CX-50 dedicated bass reflex cabinet sold separately.





Rating models


Model 25cm2 way coaxial type speaker
Reproduction frequency band 25Hz ~ 22kHz
The lowest resonance frequency (fo) 25Hz ~ 45Hz
Crossover frequency 3kHz
Output sound pressure level 102dB
Program input 20W
VC impedance 16Ω
Vibration system effective mass 24.5g
Qo 0.5 (34Hz)
Magnetic flux density Low-pass: 10,000gauss
High frequency: 13,000gauss
The total magnetic flux Low-pass: 140,000maxwell
Weight 4.5kg
Selling separately Dedicated cabinet B-1050 (\ 13,300)

 

[thomo57]

Any advice welcomed

I found these details for a ported cabinet.
The grill cloth on my cabinets are fixed so i thought if I could cut a port from the rear do you think it might be a case of suck it and see.
In this diagram the speaker is more to the top of the cabinet in mine it seems to be centred.
Can the positioning of the driver have an effect or is this again a suck it and see scenario

 

[Lanky1]

I picked up a pair of speakers with Coral 10 CX-50 in them.
I found a thread on a sealed enclosure and a ported enclosure for them.
These are in a sealed enclosure but to my eyes they aren't really sealed.
I haven't checked the seal between the speaker and face plate but the back is only held in place with 4 screws and there is a fairly large hole (half inch) which the speaker wire goes through.
There is also no form of deadening in the enclosure.

2 Questions
1: Would these benefit from ensuring the enclosure is very well sealed

2: Would they also benefit from some sort of deadening in the enclosure

I will post photos later or I do have another thread on them with photos

These are my ones, the sound is mind blowing! I must record Pink Floyd playing through them. I am just in the process of inserting posts in them.