Recommended Crossover Frequencies: 2441 & 2450 with Truextent -- Help please?

[cgregory4]

I collected the drivers: 2441 & 2450. Will order a set of the Truextent Be diaphragms, and try with both model drivers.

Assuming 2405s HF and 2235s LF, What high and low crossover frequencies would you recommend as a first run at this? First, for the 2441s and then for the 2450s?

As soon as I can sell a kidney :eek:, and then locate a pair of 2311s for sale (or trade ;)), my testing will commence. :crying:

Your help with the crossover points will be invaluable! Thanks.

Greg

[speakerdave]

You could try the 3133 biamp version (using an 800Hz horn), but why not go all in and build a 4-way? Depending which midbass cone driver you use--2122, 2123, 2202--you could then build the recast 3155 or 3145 (also biamp). The 2311, published info notwithstanding, requires a 1200 Hz crossover or higher.

[frank23]

What horns will you be using for the 2441 or 2450?

[cgregory4]

Frank, I'm trying to locate a pair of 2311s, but they are scarce as hen's teeth and expensive (hence, my effort at humour -- 'vis a vis' my reference to having to sell body parts to afford them. :o:)

Dave -- this is more of an experiment than a 'construction' right now. It will evolve into a 'real' 4-way .... I think.

However, most of what I enjoy in music is detailed mid-range -- and these drivers can cover a lot of territory. My thinking is to put together the best sounding 'mid' combination that I can afford -- then specify/fine tune the other components around it. In order to do that, it would be nice to have a starting high/low crossover for each combination.

So, in a very real sense, I am being downright lazy -- and hope some LH members have tried the Truextent with both the drivers (hopefully with the 2311s) and be able to give me some 'ballpark' crossover starting points -- points that optimize the driver/horn capabilities to the optimum extent. Everything else should fall into place. :blink:

More comments/questions, please?

Greg

[frank23]

Aha, the 2311? I have got a pair of those, including perfect slants in my pair of Olympus S8R on 375's. Hmm, maybe I should try them out once, they have been in storage since I bought them...

[ivica]

Aha, the 2311? I have got a pair of those, including perfect slants in my pair of Olympus S8R on 375's. Hmm, maybe I should try them out once, they have been in storage since I bought them...

Hi frank23,

So You are ready to apply JBL 4333/L300 network solution or Nelson Pass L300 'improvements'.


http://www.audioheritage.org/vbulletin/showthread.php?33889-Wanted-JBL-guru-to-build-new-L300-xovers&p=342372&viewfull=1#post342372

http://www.audioheritage.org/vbulletin/showthread.php?34069-New-crossovers-for-my-L300-s!&p=344152&viewfull=1#post344152


regards
ivica

[cgregory4]

Fred -- So, are you the chap with all the 2311s in storage? Small wonder that there is a shortage! ;)

Hello, Ivica. You've always been helpful to everyone -- Thank you. Can you help me understand the lack of responses to my question? Or, refer me to a past thread on the subject? This thread is 'flatter than a dead cat in the road'. :blink:

Maybe there is not much experience with the Truextent? I thought I recalled several threads on it. But I can't find them in a search -- not one that addresses my question, that is.

Maybe I can make it clearer:

1. 2441 with Truextent Be + 2311: "Sweet spot" is _____________ Hz (Low) to _________ Hz (High)

2. 2450 with Truextent Be + 2311: "Sweet spot" is _____________ Hz (Low) to _________ Hz (High)

Surely, someone can comment/compare these combinations! (I know. I'm sorry. I won't call you 'Shirley' again. :D Bad joke? OK.)

Help? Please? Someone? Anyone?

Greg

[grumpy]

If someone said it won't make much difference which driver, and to stay
above 1.2KHz (with a fairly steep slope 18dB/oct or more) and let your ear
be your guide above 9-10KHz, would that help?

[Mr. Widget]

If someone said it won't make much difference which driver, and to stay
above 1.2KHz (with a fairly steep slope 18dB/oct or more) and let your ear
be your guide above 9-10KHz, would that help?I guess the question is, would someone say that? :D


Widget

[cgregory4]

If someone said it won't make much difference which driver, and to stay
above 1.2KHz (with a fairly steep slope 18dB/oct or more) and let your ear
be your guide above 9-10KHz, would that help?

Well, Dude, you've done it again! :D

I've said it before: "The more a guy knows, the fewer words he needs." On this site, you are that guy! :applaud:

To answer your question: Yes! Absolutely! Without a doubt! Stick a fork in me -- I'm done!

Oh, yes ...... and Thank you! :bouncy:

Greg

BTW -- My kids and grandkids call me Grumpy. I have no clue why. :confused:

[grumpy]

BTW -- My kids and grandkids call me Grumpy. I have no clue why. :confused:

I hope you're not asking me... I'm pretty sure I know why -I- get called that :D



I guess the question is, would someone say that? :D

Apparently. It's the 500 questions that often follow
that personally gives me pause sometimes.:new_to_me:

[ivica]

Fred -- So, are you the chap with all the 2311s in storage? Small wonder that there is a shortage! ;)
Hello, Ivica. You've always been helpful to everyone -- Thank you. Can you help me understand the lack of responses to my
question? Or, refer me to a past thread on the subject? This thread is 'flatter than a dead cat in the road'. :blink:
Maybe there is not much experience with the Truextent? I thought I recalled several threads on it. But I can't find them in a search -- not one that addresses my question, that is.

Maybe I can make it clearer:
1. 2441 with Truextent Be + 2311: "Sweet spot" is _____________ Hz (Low) to _________ Hz (High)
2. 2450 with Truextent Be + 2311: "Sweet spot" is _____________ Hz (Low) to _________ Hz (High)
Surely, someone can comment/compare these combinations! (I know. I'm sorry. I won't call you 'Shirley' again. :D Bad joke? OK.)
Help? Please? Someone? Anyone?
Greg

Hi Greg,

It would be difficult to give You exact answers different then : " I believe that 2441 or 2450-2 would not sound different using the same horn-lenses 2311/2308 combo horn, and the same type of diaphragm"

First to say, using 2311 WITHOUT 2308 (Lenses) would be a great mistake, but if you would apply 2308 lenses then there would be no problem about the horizontal dispersion at all (as You can find in the JBL data). You can walk in the room and would not recognized almost any loss of VF sound.
1.
I have used 2441 with the Radian 4"-diaphragm (1245), applied to 2311 & 2308, and have put 10mm 'open-frame-foam' between 2308 and 2311
2.
From some other measurements using 2450-1.5 driver with Ti-SL and Be diaphragm I have recognized some ( about 2dB) more output from 2kHz up to 8kHz from the Be diaphragm.
3.
I would not expect any more differences between 2441 and 2450 using the same type of diaphragms and the same type of horns&lenses combo such as 2311 & 2308.
4.
In some other measurements I have recognized a sharp notch round 10kHz using 2441 driver, but not when short horn like
2311 & 2308 were applied.
5.
Using 2405 over say 9 kHz would be necessary
6.
Using Be-Truexten 4"-diaphragm in 2441/2450 - 2" driver and 2311 & 2308 over 700 ~ 800Hz (second order) would be acceptable, as such diaphragm has 'softer' suspension then the original JBL-Be (476) diaphragm or JBL AL-(2441) diaphragm
7.
I have applied 40uF (instead original 20uF) capacitor in 2235/31 LP section 3133/L300 network.

8.
Here are my measurements:
(i) 2445 Driver in my DIY-JAN45-2 horn (some similarities with H66000 horn) using JBL -Ti-no-rib and Be(Trext) diaphragm
(ii) 2441 Driver with Radian (1245) AL-diaphragm with 2311 & 2308 combo Horn-Lenses
(iii) 2450-1.5 Driver with JBL Ti-SL diaphragm and Be(Trext) diaphragm with JBL 2332-60 Horn

So You can conclude yourself what would be the best for your speakers.

Regards
Ivica