I have gotten a pair of Tannoy 12" paper coaxials to build my friend good quality outdoor PA speakers.
Tannoy CMS 12/8 Dual Concentric Ceiling Speaker. The factory specs show a ported box.
I will need to build boxes. Other than a standard ported, does it make sense to consider and try other enclosures in the attempt to squeeze out max performance from these drivers?
TQWT/Karlonator/Sealed TL??
thanks.
Herman
Tannoy CMS 12/8 Dual Concentric Ceiling Speaker. The factory specs show a ported box.
I will need to build boxes. Other than a standard ported, does it make sense to consider and try other enclosures in the attempt to squeeze out max performance from these drivers?
TQWT/Karlonator/Sealed TL??
thanks.
Herman
If T/S parameters are not readily available, and you don't have the wherewithal to measure for yourself, I'd be inclined to follow the manufacturer's recommendation. If you retain the net cubic volume and port size, you can play around to a degree with dimensions to suit aesthetics.
What Chris says. We did do a miniOnken for a 12" Gold, we measured its specs directly. Performance was OK (bass was excellent). The driver really needed at least an XO rebuild (40-50 year old caps would be long past their best).
dave
dave
I am still waiting on my order. Will measure them as soon as I receive them and post measurements.
I tend to avoid vented boxes
An externally hosted image should be here but it was not working when we last tested it.
what box to build?
Got the drivers, measured the 12" paper cone (tweeter and crossover disconnected).
Measurements on a open baffle test board:
No "Vas" yet. Is this needed at this point?
Got the drivers, measured the 12" paper cone (tweeter and crossover disconnected).
Measurements on a open baffle test board:
No "Vas" yet. Is this needed at this point?
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Cool. These newfangled measurement devices really do make things faster and easier. 😀
Yeah, you do need Vas. Necessary to see how big the box should be. Got double stick tape and a few nickels?
Yeah, you do need Vas. Necessary to see how big the box should be. Got double stick tape and a few nickels?
I use a donut made of plastic modeling clay. Or a donut made of silly putty which doesn't leave a residue in sensitive surfaces. Weigh the clay with a gram scale. The clay is sticky enough to stick to cone and dust cap interface.
WinISD simulates ported box, 4 cu ft, 50Hz tuning.
Tannoy factory recommended ported box, 2.9 cu ft, 48Hz tuning.
The goal is to build a very good sounding, high output PA box that will be used with a sub crossed at about 80 hz...
Are there better boxes than the ported for this Tannoy 12"?
My general preference in sound is to get dynamic midbass, clean mids and I was thinking about reducing the backwave interaction with the driver cone. Does a tapered transmission line provide any benefit here? I'm open to try exotic stuff as well!
Very motivated to squeeze out the last bit of performance here.
Tannoy factory recommended ported box, 2.9 cu ft, 48Hz tuning.
The goal is to build a very good sounding, high output PA box that will be used with a sub crossed at about 80 hz...
Are there better boxes than the ported for this Tannoy 12"?
My general preference in sound is to get dynamic midbass, clean mids and I was thinking about reducing the backwave interaction with the driver cone. Does a tapered transmission line provide any benefit here? I'm open to try exotic stuff as well!
Very motivated to squeeze out the last bit of performance here.
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it may fare decently in a stock Karlsonator12 - XRK971 could provide an estimate - even my high Q Fane sounded ok in that Karlsonator.
What is the sound difference between Karlsonator12 and vented box?
Also, how about a folded transmission line -- any advantage with this Tannoy 12? I like the idea of using the folds as additional internal bracing, but soundwise....
Also, how about a folded transmission line -- any advantage with this Tannoy 12? I like the idea of using the folds as additional internal bracing, but soundwise....
better bass, perhaps better midrange - I think tuning on the Karlsonator 12 is a bit below 40 - here's Thejessman's BG20 in the Karlsonator12
The midbass of a Karlsonator will tend to be stronger and more horn-like than a vented box. There is an elevated gain region which in most cases will act as a built in baffle step compensation. A BR will typically require BSC. Also, the presence region (~1-3kHz) will be somewhat attenuated by the bandpass action of the front chamber. That is usually a good thing since many drivers have a break up there that needs to be suppressed, but it depends. Might be too mellow with some drivers. Any Karlson type has more edges for potential diffraction and coloration. Whether this outweighs the other factors is a judgement call.
With those Tannoy specs I'd say the Karlsonator is a fair bet, depending on the freq response. It was intendended for mid Q modern pro drivers. The Tannoy is a bit on the high Qts side, but within range. Since it was a ceiling speaker, it's not going to have BSC in the crossover, so that should be good to go.
TL can be nice too. In this case I'd consider it if the speaker is to be run with SET and placed in a small room with carpet and lots of stuff. I usually like Qts around .7 for old school folded TL's. High output impedance will make up for it.
BR are simpler to build and can sound very nice. Depends on the driver and system synergy. You might need to modify the crossover in this case.
application is PA outdoor use.
no SET amps, no quiet listening at home.
my plan is to build 3 different boxes: ported/TL/Karlson
Any recommendation on how to model a tapered TL for this 12" tannoy as well as Karlsonator for this driver?
thank you!
no SET amps, no quiet listening at home.
my plan is to build 3 different boxes: ported/TL/Karlson
Any recommendation on how to model a tapered TL for this 12" tannoy as well as Karlsonator for this driver?
thank you!
TL would be a great choice for home, but IMO not for PA use. They have poor excursion control.
To model a TL, I used to use an ancient copy of Martin King's TL software, but it's no longer available. Try this one.
Karlsonator 12 should work OK. For PA use crossed to a sub at 80, you may be better off with a true Karlson cabinet. Those will have the best excursion control and therefore the highest SPL. OTOH, I personally like the TL type low bass quality of the Karlsonator, which is why I designed it... May not matter much for your app though. I've used Karlson K15 before for outdoor PA and they work really well.
The K12 is a little too small. K15 should work, but it's a little big. The X15 size is about goldilocks.
To model a TL, I used to use an ancient copy of Martin King's TL software, but it's no longer available. Try this one.
Karlsonator 12 should work OK. For PA use crossed to a sub at 80, you may be better off with a true Karlson cabinet. Those will have the best excursion control and therefore the highest SPL. OTOH, I personally like the TL type low bass quality of the Karlsonator, which is why I designed it... May not matter much for your app though. I've used Karlson K15 before for outdoor PA and they work really well.
The K12 is a little too small. K15 should work, but it's a little big. The X15 size is about goldilocks.