JBL 2226/2446/Be/350hz round wooden Edgar tractix horns

[spkrman57]

Recently there was a thread concerning Be diaphrams in JBL compression drivers which has a wealth on information and some amazing testing in which the results were shared with all the forum members.

Unfortunately the thread hit the skids and became closed.

Well, this thread has nothing to do with the testing, but it does have to do with my actually using Be diaphrams in JBL 2446 compression drivers on my 350hz Edgar tractix horns.

I had just broke in a 2-way crossover (4-Pi with components for 16 ohm LF/HF sections) with my 500hz Edgarhorns powered by Altec 299 drivers w/fresh aluminum diaphrams.

I swapped one horn at a time to guage the difference in efficiency vs the rated efficiency (JBL 2446 @ 113 db/watt vs the Altec 299 @ 115 db/watt).

I expected to have to reduce the attenuation, but actually I found the JBL's to sound more bright and alive, and I doubt I will change attenuation quite yet.

These diaphrams have not been broke in yet, so I will post more results as I get them optimized into my system. There is a definite a more open-air sound than the Altec 399's on the 500hz horns.

I previously had a pair of EV DH1-A's on these 350hz horns back last year, and they don't come close to this sound.

I will post more as I get more listening time to see what all I'm hearing, and making sure I'm not imagining these just because I have them and they are new to me.

My speakers are driven by a 300B SET tube amp @ 8 wpc!

They definitely sound VERY, VERY nice!!!

Regards,
Ron

This is a NON-professional opinion thread, I'm just a DIY'er with a little experience with tinkering!

[doucanoe]

Very cool indeed, Ron!


I look forward to hearing your thoughts as things settle in. After a great start with the guys, it looks like the 2446 might just end up being the vehicle that brings the Be diaphragm to the dance.

For me, maybe someday, maybe someday...


RC

[eso]

The Edgar 350 Hz round tractrix horns were designed for 2" format compression drivers, so they should sound better with one instead of a 1.4" format driver that requires a throat adapter, regardless of diaphram differences.

Not to say the the BE diaphram isn't an improvement. Quite likely it does provide extended bandwidth.

I've been following the TureXtent Diaphram threads with interest, and want to try out some 1" format for my Coaxial experiments once they become available.

Have you used tweeters with your system? My main horn system have 280Hx round tractrix horns with 2440 drivers and Fostex T925a alnico horn tweeters and I get plenty of high frequency extension, and detail using stock JBL diaphrams.


eso

[robertbartsch]

What was the cost of the BE diaphragms if I might ask?

I have one similar system in my basement; drivers are 2225, 2445 and 2402. I'm not a fan of Ti frames but the use of a UHF tweeter seems to eliminate much of the annoying harshness of Ti....

[spkrman57]

Have you used tweeters with your system?
eso

I don't care to use tweeters if I don't have to as I can get some incredible holographic imaging with my round horns and a good 15" LF on the bottom.

I'm also over the age of 50 and my hearing is not what it used to be. I can hear to approx 14 khz, after that there's not much.

I will say that I don't feel the need for tweeters with this setup!

Regards, Ron

[spkrman57]

What was the cost of the BE diaphragms if I might ask?

I have one similar system in my basement; drivers are 2225, 2445 and 2402. I'm not a fan of Ti frames but the use of a UHF tweeter seems to eliminate much of the annoying harshness of Ti....

I did some horse-trading for my diaphrams, but I'm sure Dan or Brad will contact you.

The beauty of the Be diaphrams is that you get the extension of the Ti diaphrams, without the annoying sizzle that Ti brings along.

Ron

[Mr. Widget]

Looks like fun... and I bet it does sound great.

I've got a question about your horns. How does that plywood mount work? Is it a straight 2" bore or is it part of the horn's tractrix taper?


Widget

[spkrman57]

Looks like fun... and I bet it does sound great.

I've got a question about your horns. How does that plywood mount work? Is it a straight 2" bore or is it part of the horn's tractrix taper?


Widget

The 2" throat starts the taper on the 350 hz Edgar tractix horns.

I can't wait until these diaphrams get broke-in!

I wonder how long Be takes to break-in?

It sounds pretty good right from the start though, I can hear the changing of the tonal character as she gets more time cook'n in!

Regards, Ron

[spkrman57]

I'm currently using 1.6 khz crossover and while I'm listening to these diaphrams break-in I'll be building my 800 hz crossover.

I think 800 hz will sound pretty good. I can't say I can find anything wrong with the 1.6 khz crossover either.

I don't know what this would sound like with SS, but with tubes is very open and alive.

Actually I can't come up with the proper words to describe the sound I'm hearing.

Easiest thing that comes to mind is "non-fatiguing". Most folks don't like horns because they can be fatiguing if not set up right, or they just don't have a decent response curve to them.

Ron

[grumpy]

pardon my crayon-like drawing... I'm re-asking Widget's question
graphically, because I didn't understand your response:

[spkrman57]

not the JBL 2446.

I'm not the expert on the 2446, but the Edgar horn flare starts at the throat where the driver is mounted.

Ron

[grumpy]

Thanks. Made it into my thick skull this time.

[djnagle]

The Edgar 350 Hz round tractrix horns were designed for 2" format compression drivers, so they should sound better with one instead of a 1.4" format driver that requires a throat adapter, regardless of diaphram differences.

Not to say the the BE diaphram isn't an improvement. Quite likely it does provide extended bandwidth.

I've been following the TureXtent Diaphram threads with interest, and want to try out some 1" format for my Coaxial experiments once they become available.

Have you used tweeters with your system? My main horn system have 280Hx round tractrix horns with 2440 drivers and Fostex T925a alnico horn tweeters and I get plenty of high frequency extension, and detail using stock JBL diaphrams.


eso

Hey Eso, I have the 2440 on 400hz horns and I had them on the Edgars as well. The 244X Be is night and day compared to the stock diaphragms. No need for a tweeter with the Be.

[Mr. Widget]

The 244X Be is night and day compared to the stock diaphragms.

Very cool... I never liked Ti myself, though I must admit I haven't experimented with the aquaplas coated versions.

No need for a tweeter with the Be.

I am not so sure this is a universal truth.


Widget

[spkrman57]

would most likely be a individual preference.

I have a sensitivity to UHF notes that give me earaches when voiced too hot, so I prefer a slightly rolled off upper HF response.

I also can't hear up to 20 khz, so it's a easy decision for me.

Last night when I finally shut the system down I finally decided that the HF extension was better than any other MF/HF horn driver I've heard before. I'm not counting tweeter horns, only compression drivers and horns that could be crossed over @ 1.6 khz and lower.

This compression driver and Be diaphram on the 350 hz Edgarhorns is doing the job quite nicely for me. Others may require a tweeter, but not me!

Ron