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matsj
08-13-2005, 11:24 AM
Hello everybody

I`m planning to build 2 new speakers with 4 2226h + 2 2446h/j with tractrix horn. I have read about the project May and want to build something similar.

I dont know if i`m going to use ported or sealed boxes to my 2226. Today i have sealed boxes to them but i think they are too big ( 140 liters each).

If someone have a speaker program i would be happy if they could run some tests on ported vs sealed box to me. F-3db under 40 hz.

I`m planning to have tractrix center 40" up.

Every opinion is useful.

Br mats

speakerdave
08-13-2005, 11:59 AM
Is this for in-home listening or PA?

I can't answer your question direct, but I wanted to tell you that I just happened to notice on an old thread that Giskard used to make an MTM version of the 4435, everything else the same. The woofer for that speaker both stock and Giskard's custom is the 2234. The 2234 is the 2235 without the mass ring. If you want low bass I would recommend you consider this driver. Using the woofers in pairs the bass is reinforced up to a certain frequency depending on the distance between them.

Do you mean a mid/high horn 40 inches tall? If so your second woofer will be very high.

What is your planned crossover frquency?

David

Mr. Widget
08-13-2005, 12:22 PM
JBL recommends the 2226 in 113 liter boxes tuned to 40Hz. They will yield an F3 of 68Hz.

The 2226 is a midbass driver and really won't give you a deep bass response without EQ, corner loading etc.

Widget

matsj
08-13-2005, 12:39 PM
Hello david


I`m going to have them at home. The tractrix horn is not 40" ,the 2446 driver will be placed 40" up from floor. The tractrix horn is around 15".

I`m not sure over the crossover frequency but around 500-700 hz maybe, if i crossed at 700hz the distans on woofers cc will be 48 cm.
If i crossed at 400hz the cc will be 85 cm

Doesnt the 2235 need a bigger box then 2226 around 170 liter ? But it goes 10hz lower in freqvency.

br mats

matsj
08-13-2005, 12:46 PM
I have 4 2245 in 4 ported boxes playing up to 50hz today :) :D so they really dont have to play so low. Maybe i should cross the 2245 / 2226 at 80hz instead.


br mats

yggdrasil
08-13-2005, 06:15 PM
Hi Mats.



You could try WinISD. http://www.linearteam.dk/

It will give you many answers.

matsj
08-13-2005, 10:53 PM
Tack / Thank you Johnny


I will try the program and se how small cabinets i could get.

br mats

speakerdave
08-14-2005, 05:11 PM
Have you read Drew Daniels's description of a system for Ancient Audiophiles? What you are planning has some similarities. You should read his paper.

This is the first version: It uses 2 2245's per side up to 80 Hz and then a 2220 up to 300 and then goes to a a cone mid/bass up to 1200 and then the horn.

http://www.audioheritage.org/html/perspectives/drews-clues/audiophile.htm

Here is a later version using 2242's and then the 2227 in place of the 2220.

http://www.audioheritage.org/html/perspectives/drews-clues/system.htm

The 2227 is now out of production, I believe. I think these are both lighter-coned drivers than the 2226 and so more suitable for going up into the midrange. The 2226 is a kind of all-purpose driver. If you are going to limit bandwidth you might as well use specialized drivers.

I would recommend you read these system descriptions in detail before going any further with your plans.

By the way, I think the system you are planning, if it's for normal in-home listening, is massive overkill and dangerous to your hearing longevity.

David

johnaec
08-14-2005, 06:47 PM
The 2227 is now out of production, I believe.It's still listed among the current components at jblpro: http://www.jblpro.com/pages/components/svg.htm#2227H

John

speakerdave
08-14-2005, 09:17 PM
Thanks for that, John. Not sure what it means in terms of actually getting some, since it's not on the transducer list, but I guess it's still current product.

David

matsj
08-15-2005, 11:22 AM
Yes i have read drews system . I know how high i can play with my system but you dont have to :) :D . If you take 2 woofers you come closer to the 2" horn driver in spl and you dont need big amplifiers to push.

My last speaker were 2 15" with the 2" driver on top and i didnt liked it, because the driver is 46" up from floor and i want it around 39"-40". So i will build new enclosures with K2 s 9500 and project may in my mind. I have heard K2 s9500 one time in stockholm ( Niklas Nord) and i was sold. I liked the design AND SOUND on it.
Maybe i`m going to visit him in a near future again.

I already have the drivers / 4x 2446. 11x2226 and 4x 2245) so i`m going to use them. I dont think you can buy the 2227 in sweden and if you could do it it will be very very expensive.

Maybe i`m going build 2 midbas horn 80-400hz with the 2446 in the middle, i can`t deside.

sorry for my bad spelling.

mats

speakerdave
08-15-2005, 12:15 PM
OK. I'm beginning to get the picture. I'm working on a similar idea, although I will be doing without subwoofers and want to try for a two-way with two pair of 1400nd's and ???? horn and driver in the middle. The plan is that it will eventually be TAD 4003 on a horn similar to theirs, but I need to get some of my ducks in a row before making the big cash plunge. In the meantime I will try Altec 288-16 G on 511E (well-damped), JBL 2441 on 2397 with 077's added, possibly the 2447 with the coated diaphragm to see what happens. Right now I am converting some old enclosures into top and bottom woofer modules for the test bed. As I understand it the 1400nd has a rising response on axis, so it therefore (I think) works well in this configuration because of the acoustic coupling of the woofers at lower frequencies. I will be using staggered tuning similar to the M9500 for a more gradual roll off of the bass that will play into room rise. If when I get that done I think I need to add a subwoofer I will rebuild with S9500-sized enclosures and add a couple of subs, but I do not think that will be necessary. I must be living in a smaller cave than you.

I enjoy hearing about your project, and hope you will keep us posted on progress.

David

speakerdave
08-15-2005, 12:38 PM
Doesnt the 2235 need a bigger box then 2226 around 170 liter ? But it goes 10hz lower in freqvency.

It's easy to misread that JBL enclosure glide. I do not think those enclosure tuning frequencies are 3 dB down points. I don't have the software to check this, but I believe the 2235 in its recommended enclosure will yield a full octave lower bass than the 2226 in its recommended enclosure (although perhaps not at the same SPL).

David

matsj
08-15-2005, 01:25 PM
Mr.widget post a picture in my taste in ( 2-way double 15 speaker thread) that could be mine. :D David maybe you should try 2451+2332 dms horn, i will keep posting when the building starts.

Racerextreme have posted some pictures of big horns but i can`t find any link on those ( french ).

Br mats

speakerdave
08-15-2005, 02:11 PM
David maybe you should try 2451+2332 dms horn . . .

I've thought of that. I have the 2447's on hand; not sure what the differences would be between those and the 2451 besides the magnet material. Believe they have the same phase plugs. Magnetic field in the 2451 is .05 T more intense, which would theoretically help with the high frequencies, a key factor in a two-way application, but the published frequency response curves of the two are virtually identical. I don't think I have a published curve of any driver with the coated titanium diaphragm. I assume that it would weigh a little more, and that the slight increase in magnetic field intensity would help with that, but I expect the major benefit would be to smooth the very ragged response of the titanium above 10k and quell that breakup peak at 5k.

I've noticed that the field intensity specifications of the ferrite magnets is sometimes less. I wonder if this is because there is less expectation of loss. For example, the 2425 is usually seen as being comparable to the Alnico 2420, but in fact its field strength is spec'ed the same as the 2410. (Just babbling on here.)

For now I am not going to be trying the 2332 because know I want a lower crossover. If I get to considering the 2332 again, I have some 2435's here to try.

David

Zilch
08-15-2005, 03:36 PM
We are not having good experiences with 243x on 2332 horns over in the "Quick and Dirty" thread.... :(

"Optimized Aperture," I believe it is....

Mr. Widget
08-15-2005, 03:47 PM
"Optimized Aperture," I believe it is....

Have you found and tested one that can be crossed over at 800Hz or lower?

Widget

Zilch
08-15-2005, 04:13 PM
Have you found and tested one that can be crossed over at 800Hz or lower?Nope. 1 kHz, basically.

There's the BIG horns, of course: http://www.jblpro.com/pages/components/23525354.htm#2352

speakerdave
08-15-2005, 04:14 PM
We are not having good experiences with 243x on 2332 horns over in the "Quick and Dirty" thread . . .
Yeah, I've been noticing that, thus my dismissal of the idea for the moment. That driver seems to work better on the TAD type horn (but that does not allow for a UHF driver in the spacing I want.


"Optimized Aperture," I believe it is....
What do you mean? I have taken "O.A" to refer to the liberation of the driver throat/horn entrance expansion rates that have been locked in since the thirties when they were optimized for much lower frequencies than are generally used now. The 2447,245x and 243x families of drivers do not have throats with those expansion rates and therefore do not need old style horns with the expansion rates married to those throats. Ergo . . . a new horn entrance called "O.A" Am I wrong about this? Do you think there is a problem with the new horn entrance design?

David

speakerdave
08-15-2005, 04:16 PM
Nope. 1 kHz, basically....
Yeah, I see that, too. The 2435 may be a good driver for the 4348 style of speaker with that horn.

David

Zilch
08-15-2005, 04:28 PM
Yeah, I see that, too. The 2435 may be a good driver for the 4348 style of speaker with that horn.O.K., H9800, then, for 800 Hz, and you can tell US if the back cap is a problem.... :p

Regarding "Optimized Aperture," I just see "Specifically designed for 2447 and 2451" and wonder if 243x is really applicable as well.

speakerdave
08-15-2005, 05:15 PM
O.K., H9800, then, for 800 Hz, and you can tell US if the back cap is a problem . . .
I thought you had found that playing on the TH4003 the back cap was irrelevant. Anyway, I think the 4348 crosses into the horn at 1 or 1.2 kHz.


Regarding "Optimized Aperture," I just see "Specifically designed for 2447 and 2451" and wonder if 243x is really applicable as well.
I don't see why not. I have wondered about this because of the differences in the diaphragm sizes, but I think that would just make a difference in pressure, which would vary all over the place anyway. But I dunno . . . . I have not seen the 2332 described as "O.A" nor dedicated to the 2447 and 2451. That literature for the 2352 etc that says that I believe predates the production of the 243x family of drivers. But you are right in that the 2332 (and the 2381) are both 1.5" drivers that have never been used in a production speaker with the 243x group.

Anyway, your testing is more interesting to me than all my conjecture.

David

Zilch
08-15-2005, 05:30 PM
I have not seen the 2332 described as "O.A." DMS-1 data sheet and others call it that.

It's also used for HF (nominal) with 2451 in 5671 theater system crossed at 2.3 kHz.

http://www.jblpro.com/pub/cinema/5671.pdf