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Kay Pirinha
04-26-2019, 11:57 AM
Hi,

as I could get a pair of 2342 horns plus 2425 compression drivers plus xover networks for reasonable money, I'd ask if there are 4425 enclosure drawings available anywhere? And what's the bass driver in this monitor?

Best regards!

Robh3606
04-26-2019, 12:17 PM
Make sure you get the correct version of the 2425. The 2342 is a screw on horn not a flange mount.

Rob:)

Kay Pirinha
04-26-2019, 01:26 PM
Drivers and horns still are fixed together ;).

Best regards!

RMC
04-27-2019, 12:05 PM
Hi Kay,

RE: "And what's the bass driver in this monitor?"

The 2214H naturally! Regards,

Richard

Kay Pirinha
04-27-2019, 01:02 PM
Thanks!

Seems that I have to give up the idea, since the 2214H also is obsolete :(.

Best regards!

hjames
04-30-2019, 06:44 AM
Thanks!

Seems that I have to give up the idea, since the 2214H also is obsolete :(.

Best regards!

Okay, but - the 2214H drivers ARE available -
they were used in a number of speakers.
I sold a used pair of them (with fresh surrounds) just last fall.

Kay Pirinha
04-30-2019, 06:49 AM
Well, due to vertiginous s/h, taxes and customs fees, I'd have to search for them in Europe. Without success 'till now :crying:.

Best regards!

RMC
04-30-2019, 05:21 PM
Hi Kay,

RE: "I'd have to search for them in Europe. Without success 'till now"


Not long ago I did a relatively extensive search for a similar or replacement driver to the 2214H, though I haven't decided at this time to let go the pair I have, considering the amount of work I put into these...

Some folks who sell these used drivers mention they have replaced the surrounds. Nice, but which replacement surround model did they effectively used: generic one as sometime seen or the model specifically made for the 2214H? Then, I rarely hear people mentioning they also took the time required to remove all the foam rot inside the driver since when due for a surround refoam its probably also due for an inside foam removal, which requires cutting the dustcap, and by the same token clean the gap of migrating dust, dirt or foam! Moreover, some barely or don't remove at all the old glue left on the back side of the cone before glueing the new surround on it, therefore adding a little cone mass. I even saw some with surround glued to front of cone, since its easier than on back side! Having gone through the whole process meticulously, plus made myself some "tools" to do it, I can certify its a real monk's job to do it right.

Now I try to stay away from foam surround drivers as much as I can, having learned the hard way with 2214. I still have another smaller pair I like waiting to be refoamed. This brings me to an acceptable replacement driver (not a clone) I found for the 2214H: SB Acoustics 12" SB34NRXL75-8 which is still available on their Web site, sbacoustics.com (be careful with exact model number as they also have two other 12" in the NRX series with very similar model numbers, but the other two are not suitable here, e.g. much too high Qts).

The above model is the closest thing I've ever found yet, parameters wise, its from Denmark, Europe, so not too far from you and there's a German distributor for SB Acoustics called intertechnik.de (for USA folks Madisound sells that SB driver for $245.US, and in Canada Solen.ca sells it for $325. CAD + tx).

I have three pairs of smaller woofers from SB Acoustics (with rubber surrounds), I'm quite satisfied with them, and the next pair could be the model mentioned above... It has rubber surround which lasts a lot longer than foam, plus many assets pretty close to or the same with the 2214H.

Its not a simple drop-in replacement though. The main drawback is the SB driver size (overall diameter & hole cutout mainly, driver depth to a lesser extent) being a larger 12" than many (more like 13"). Not a big deal when a box isn't constructed yet. In some cases where it is already made there may still be hope depending on box dimensions (too large for an exact clone 4425 box). The SB acoustics would probably need to be crossed over a little lower than the 2214H's 1.2 khz used in the 4425 (but 800 hz was used in L100T and L100T3).

The SB's Fs, Qts and Vas for box sizing/tuning are reasonably close to 2214, the little higher Qts would probably be offset by its little lower Vas re box size. Sensitivity, cone mass, Le, BL, Flux, power handling, 3" VC, etc. are also comparable. The 2214H has Re rated 5.6 ohm but its DCR min.-max. or tolerance is 5.1 to 6.3 ohms, the SB has 6.2 ohm rating.

On the other hand, the SB woofer has Xmax 10 mm vs 6.6 mm for 2214H so that's a nice gain for bass lovers.

I'm not pretending both drivers will sound the exact same, but rather the SB woofer is a worthwhile option to consider, more so when the box allows the flexibility to fit it in. Another member has previously suggested the Fostex FW305 woofer as a possible replacement for 2214, however if you look closely and compare carefully its not as close to the 2214H as the SB driver is. The Fostex also appears to have a foam surround which would be a definite deal breaker for me... Regards,

Richard

Kay Pirinha
05-01-2019, 01:02 AM
Thanks for your valuable hints, Richard. I appreciate them!

Is there really foam somewherein the 2214H, besides the foam surrounds? That surprises me! I recall having replaced the foam in my 2421A compressin driver (I reported of), but in a woofer?!?

Intertechnik is well known to me. Just a few days ago I received a package from them with inductors of 2.7 mH, 1.8 mH, and 50 µH resp. that I tweaked for 2.6mH, 1.6 mH, and 40µH for my 4430 project. A very reliable distributor that ships within only two or three days after the order. They also offer to customly wind inductors, but as I've got a DE-5000 LCR meter ;)...

Best regards!

RMC
05-01-2019, 10:04 AM
Hi Kay,

To cover the back vent hole, in order to prevent dust or other matters from entering inside the driver, JBL woofers have what they call a "Foam vent plug or screen". My 2205 have a screen and my 2214 had a foam which seemed like more than just a plug but since it was desintegrated its difficult to tell exact shape and some had migrated inside drivers...

Having worked my head off to take all of that crap out I can really swear THERE IS REALLY FOAM INSIDE A 2214H. The easiest way I found to make-up for that removed "foam plug", in order to cover the back vent hole again, is to glue a piece of speaker grill cloth, slightly stretched, over the back vent hole so this will act as a "screen" and minimize things, such as dust and loose fiberglass fibers, from entering the driver while air still passes through the cloth. Regards,

Richard

Kay Pirinha
05-01-2019, 12:29 PM
This is a good solution for sure, 'cause the existance or non-existance of foam in the rather small vent won't affect LF performance.

Best regards!

RMC
05-02-2019, 09:18 PM
Hi Kay,

RE: 'cause the existance or non-existance of foam in the rather small vent won't affect LF performance.

The existence or not of something appropriate covering the back vent hole may have an impact over time on LF performance if, for example, too much dust or fibers accumulate in the woofer and migrate into the gap. The drivers' Design Engineer sure had a good reason in mind to specify the presence of a screen or foam for a driver's back vent. Otherwise none would be there as it represents an additional manufacturing cost...

Regards,

Richard

Kay Pirinha
05-03-2019, 03:02 AM
Hi Richard,

I think I was somewhat unprecise. It's clear to me what the foam or grille does. But the foam per se won't affect the performance. So it doesn't matter if there is foam or a grille in/at the vent.

Best regards!