Upgrade: SAM1HF or 2452H-SL in ScreenArray horn?

[Jonas_h]

I am currently using a ScreenArray horn with a 2432H compression driver. I really like the sound, but I feel I am missing some resolution and extensions in the high frequencies. I have thought about upgrading to either the SAM1HF horn/drivers or getting a 2452H-SL driver for my current horn. I have heard the SAM1HF and really like it, but I have read many good things about the 2452H-SL and like the fact that it is a 4" driver which covers the whole spectrum.

All inputs are appreciated

[Mr. Widget]

The SAM horn with a 4" Truextent Be diaphragm in an appropriate JBL driver would likely be the current ultimate upgrade. That said, I have been quite happy withe the stock 435ALs.


Widget

[4313B]

I am currently using a ScreenArray horn with a 2432H compression driver. I really like the sound, but I feel I am missing some resolution and extensions in the high frequencies. I have thought about upgrading to either the SAM1HF horn/drivers or getting a 2452H-SL driver for my current horn. I have heard the SAM1HF and really like it, but I have read many good things about the 2452H-SL and like the fact that it is a 4" driver which covers the whole spectrum.All inputs are appreciated

I'll second what Mr. Widget posted. The 435Al and 2431H are quite good. And you can always swap in the 2435 diaphragm if you want a Be solution (not aquaplased like the 435Be diaphragm, which is virtually unobtainable). You'd have to hassle with the ferrofluid but Doug Button gave us the exact type and amount for the 435/2435 core and RobH3606 knows where to order it from.

2452H-SL? Don't you mean the 2450SL with Truextent Be diaphragm?

[Jonas_h]

What are the difference between the 2431H and 2432H besides AL vs. TI?

I do actually mean the 2452H-SL - aquaplas damped titanium driver.

[4313B]

I do actually mean the 2452H-SL - aquaplas damped titanium driver.

I'm pretty sure you mean the 2450SL with Truextent BE diaphragm but I could be wrong.

[pos]

What are the difference between the 2431H and 2432H besides AL vs. TI?

I do actually mean the 2452H-SL - aquaplas damped titanium driver.

The 2432H has an additonal "snout" that helps avoiding problems (sharp dips above 10khz, that get worse off axis) with short/rapid flare horns (like the PT waveguides or 2332).
But if the SAM horn is anything like the h9800 (and I think it is very similar) the 2431 would not have any problem with it.
The best choise with that horn would probably be the 435Be or 2435.
I am using a 2450SL+Be diaphragm and the difference with the 2435 is not that big on the H9800...
(horizontal directivity is better though, but with the vertical horn the directivity is quite similar, with the slot doing all the hard work)

[Jonas_h]

I'm pretty sure you mean the 2450SL with Truextent BE diaphragm but I could be wrong.

http://www.jblpro.com/catalog/genera...?PId=325&MId=1

The 2432H has an additonal "snout" that helps avoiding problems (sharp dips above 10khz, that get worse off axis) with short/rapid flare horns (like the PT waveguides or 2332).
But if the SAM horn is anything like the h9800 (and I think it is very similar) the 2431 would not have any problem with it.
The best choise with that horn would probably be the 435Be or 2435.
I am using a 2450SL+Be diaphragm and the difference with the 2435 is not that big on the H9800...
(horizontal directivity is better though, but with the vertical horn the directivity is quite similar, with the slot doing all the hard work)

I'm only interested in "stock" components. So either the SAM1HF or a new driver for my current horn.

[4313B]

I am using a 2450SL+Be diaphragm

If I'm not mistaken, that should be about as close as one can get to a 476Mg or 476Be using Pro parts.

and the difference with the 2435 is not that big on the H9800

Hmm.

[cooky1257]

Hmm, I use the 2452+Truextent Be on H9800(correct throat) clone at the mo' and it is a noticeable improvement over the 2435, ditto on the SAM1.
As I recall Zilch was full of praise for the stock 2452.

[4313B]

Hmm, I use the 2452+Truextent Be on H9800(correct throat) clone at the mo' and it is a noticeable improvement over the 2435, ditto on the SAM1.

It should be with the Be diaphragm. G.T. expressed his reservations with respect to replacing a 435Be or 2435H with it in stock form though. I believe he felt the 3-inch Be diaphragm trumped the larger 4-inch Ti and Al diaphragms. I do remember him being quite impressed when he swapped out his 435Be's for 476Be's on the Array horns. Such swaps require network rework due to impedance, phase, and frequency response differences.

I personally am thoroughly impressed with the 435Be and 2435 on the Array horn.

As I recall Zilch was full of praise for the stock 2452.

Back when Zilch was first starting out on the econowave thing we had a chat on the phone with respect to these various compression drivers. I passed along to him the notes from my several in depth conversations with JBL. At that time I expressed my irritation with the fact that the 2452 was nearly the same price as the 2450 given that it allegedly enjoyed a considerable savings in manufacturing. I really don't know what Zilch did with all that information or what he finally determined to be the most desirable combination.

If I'm not mistaken (and I very well could be), if someone is buying a new compression driver from JBL Pro in hopes of somewhat emulating a 476Be or 476Mg, I believe the 2450SL is the model to get along with a Truextent Be diapraghm. I'm not sure what the total cost of that package is. I've never looked into it. I haven't been paying a whole lot of attention to Pro for quite some time now. According to several sources at JBL, that should get one to about 80% of a 476Be or 476Mg. Who knows, maybe a 2452 is "eighty percent" too depending on the horn? I just don't know at this point. That was a long time ago.

[cooky1257]

Doesn't the 2450 have the coherent phase plug a la 476? The 2452 looks like an enlarged version of the 2435. For the money, even 80% is worth having.I thought the extra cost of the 2452 was down to the neo mag?
Frank

[pos]

The 2452 also has the 4-slit coherent wave phasing plug, albeit a bit shorter.
In my tests the 2450SL core outperformed the 2452 one by quite a margin.
I don't know how to express that, but the dynamic was more realistic on the 2450. The 2452 sounded more "fake" in this regard.
I think is has to do with the "optimized" magnet sturcture of the 2452 (field distortion?...)
I found the 2452 and 2435 both shared this trait...

Strangely the difference was more obvious on short waveguides than on the H9800 for example.

[cooky1257]

Pos,
When you say 'tests' you mean listening don't you?
As I recall you didn't actually measure the 2452, please correct me if I'm wrong
I've always understood the coherent wave phase plug slots to be curved cross section-the 2452/2435 look straight.

Cooky

[pos]

I did a lot of measurements too (more measurement than listening tests in fact).
I tested (measurement and listening tests) Ti SL and Ti ribbed diaphragms in both cores, but I didn't installed the Be diaphragms in the 2452.
With the same diaphragms installed, the 2452 measured almost exactly like the 2450SL, with only a slight boost in the lower range due to the smaller back cap.
The directivity behavior was also identical, and much better than the 2435 (but the slot in the array horn makes it a moot point).

I don't know what measurement could illustrate the differences I heard in the listening tests, but I imagine it is always the case with magnet-related issues (alnico vs ferrite vs field coild vs...)

[cooky1257]

I did a lot of measurements too (more measurement than listening tests in fact).
I tested (measurement and listening tests) Ti SL and Ti ribbed diaphragms in both cores, but I didn't installed the Be diaphragms in the 2452.
With the same diaphragms installed, the 2452 measured almost exactly like the 2450SL, with only a slight boost in the lower range due to the smaller back cap.
The directivity behavior was also identical, and much better than the 2435 (but the slot in the array horn makes it a moot point).

I don't know what measurement could illustrate the differences I heard in the listening tests, but I imagine it is always the case with magnet-related issues (alnico vs ferrite vs field coild vs...)

Thanks.