Results 1 to 14 of 14

Thread: Large Format Compression Driver Listening Impressions

  1. #1
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,200

    Large Format Compression Driver Listening Impressions

    Hello

    Curious about others experiences with these drivers. I got a big surprise when I started listening to my 476Mg's that I didn't expect. I have 2435's in my 2 other horn/waveguide systems and was a bit shocked by the differences. The 476's are so relaxed and the dynamics are really impressive. I guess it goes back to "explosive waveforms" in the old JBL advertising.

    I am really curious if any of the M2 clone users have compared any of the 2450 family of drivers to the new 2430 driver and what their impressions were of any differences. It seems with these newer drivers they are optimizing them to crossover higher and extending the upper frequency response to well above 20K. The 2450 family seem to have better LF ability and reserve looking at measurements. So they are actually a bit opposite bandwidth wise.

    So if surface area is the key to this difference how does it show up in head to head listening differences. I have never heard a 2430 driver so I am at a loss and wonder if there are differences like I hear with the 3" drivers I have been listening to for years.

    Rob
    "I could be arguing in my spare time"

  2. #2
    Senior Member ivica's Avatar
    Join Date
    Jan 2008
    Location
    serbia
    Posts
    1,650
    Quote Originally Posted by Robh3606 View Post
    Hello

    Curious about others experiences with these drivers. I got a big surprise when I started listening to my 476Mg's that I didn't expect. I have 2435's in my 2 other horn/waveguide systems and was a bit shocked by the differences. The 476's are so relaxed and the dynamics are really impressive. I guess it goes back to "explosive waveforms" in the old JBL advertising.

    I am really curious if any of the M2 clone users have compared any of the 2450 family of drivers to the new 2430 driver and what their impressions were of any differences. It seems with these newer drivers they are optimizing them to crossover higher and extending the upper frequency response to well above 20K. The 2450 family seem to have better LF ability and reserve looking at measurements. So they are actually a bit opposite bandwidth wise.

    So if surface area is the key to this difference how does it show up in head to head listening differences. I have never heard a 2430 driver so I am at a loss and wonder if there are differences like I hear with the 3" drivers I have been listening to for years.

    Rob
    Hi Rob,

    I think that using one of the best (neglecting for the moment stellar 476Be) JBL compression driver 476Mg is privilege for the small number of audio enthusiast.
    I have been very happy when I have changed my JBL 2420&2312&2308 with 2441&2311&2308 in my 4333 DIY clone speakers.

    Redards
    Ivica

  3. #3
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    10,295
    Quote Originally Posted by ivica View Post
    I have been very happy when I have changed my JBL 2420&2312&2308 with 2441&2311&2308 in my 4333 DIY clone speakers.
    I have owned LE85s (2420s) and used them in a number of systems over the years. My LE85s had been sent back to JBL and been refurbished by them... You used to be able to do that. I make the distinction as so many times we take if for granted that a working driver is also a properly working driver and through experience, I have discovered that this is far from the truth.

    In my early days on this forum I decided to pursue one of popular big kahuna 43XX DIY systems... I built a pair of 4355 clones. For that project I found a pair of 2441s and had them rebuilt by JBL, new throats, diaphragms, alignment and re-magnetizing. I ultimately decided while the 4355 has its charms and all, it wasn't the system for me, but damn if that 4" driver didn't blow me away!

    I have since had TAD TD-4001, TAD TD-4003, and JBL 476Be drivers and have been smitten with them all. During this time I also had the 435AL 3" drivers... I am not sure why, but they just don't have the ease and tactile qualities of the big 4" beasts! If you have the budget, buy the best 4" diaphragmed drivers you can get (2" exit or 1.5" exit). You won't be disappointed!



    Widget

  4. #4
    Dang. Amateur speakerdave's Avatar
    Join Date
    May 2003
    Location
    Northern California
    Posts
    3,610
    Yeah, "steep waveforms of explosive loudness" (1976 catalogue copy for the 375. I still have my well-worn copy). Love the expression. I suppose in a hard-driven sound reenforcement situation that was it, but in the home I experienced it as the relaxed but superlative dynamics of which you speak when I experimented with 2450's with dusted diaphragms on 2311 horns in my 4345's.
    "Audio is filled with dangerous amateurs." --- Tim de Paravicini

  5. #5
    Member Mitchco's Avatar
    Join Date
    Feb 2013
    Location
    Sunshine Coast, Canada
    Posts
    74
    Hi Rob, user notnyt over at the AVSForum compared the 2430 with some large format JBL CD's on a 2384 waveguide, summarized:

    https://www.avsforum.com/forum/89-sp...l#post42167329

    While not an M2 waveguide, it does support your theory. There are measurement details for each of the CD's tested. For the 2430 one can see there are some distortion issues towards its lower limit: https://www.avsforum.com/forum/89-sp...l#post41945689

    I had the 3" 2432 on the 2384 and switched to the 4" 2453h-SL and thought it was a major improvement overall - smoother frequency response, better low end response with lower distortion, and the coating makes for reasonable HF extension. I would love to try in on an M2 waveguide.

    Kind regards,
    Mitch

  6. #6
    Senior Member srm51555's Avatar
    Join Date
    May 2013
    Location
    Wisconsin
    Posts
    536
    To me the JBL large format drivers with new diaphragms are hard to beat for the money. I had the proper D2430K's in my M2 build but didn't care for the result vs my 2440 with be on a three way build.

    From GT here:
    " The 2430 needs to be used an octave below where it is happy (as in the M2) and has an increased amount of 2nd harmonic distortion between 750 Hz and 1500 Hz as a result. It is not horrible, but it is about 10 dB higher than the 476Mg in that range and up to 20 dB higher than the 476Be over the same octave."

  7. #7
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,200
    Thanks for the replies I missed some of this and it is great info!

    Rob
    "I could be arguing in my spare time"

  8. #8
    Senior Member 1audiohack's Avatar
    Join Date
    Jul 2007
    Location
    Las Vegas Nevada
    Posts
    2,799
    Ha Iím always late!

    I built my daughter a pair of 4333Aís from a pair of hacked of JBL cabs that came out of UCLA 100 years ago.

    We ran a ton of parts through these. Started with 2235, 2420 on both 2312 and 2307 horns and 2405ĎS. 3110A and 3115A crossovers and 3108ís for the 2405ís. I could get any combination to measure fairly well and sound reasonable but I just could not love them.

    Yanked all the passives, made block off plates and employed a dbx zonepro. Better but just no life.

    I am a hack so, I took the 2307s to the lathe and parted them off where the throat was just under 1.5Ē in diameter, machined flanges to accept a pair 2451SLís and fired up the TIG.

    Back on the lathe this allowed me to enter the horn after a soft radius at 7.5 degrees from the phase plug exit cheating out a faster entry shorter expo horn that totally looks the part of the old 4333ís and, drum roll, the whole part I didnít like is gone.

    My experience with small format drivers always ends like this.

    When I finally got the 4338 horns done, the first thing I put on them was a pair of 2451SLís and they sound great. Next a pair of M2 D2ís and the magic is gone. Didnít surprise me at all but I still keep trying to like them.

    They D2ís are great tweeters. On top of a pair of 2482ís crossed in about 5.3KHz, magic.

    Barry.
    If we knew what the hell we were doing, we wouldn't call it research would we.

  9. #9
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,200
    So now I went and did it! Got a pair of 2453SL to try a driver swap in my basement system. Wow it's one thing to look at pictures but I didn't realize how much smaller they have managed to get the 4" drivers. Not much bigger that the 2430's/435 drivers but with a really significant difference in diaphragm size. It still has a 4 slit phase plug but obviously shorter in length. Would love to see a cross section drawing to compare with a 2450 SL/476. Can't wait to fire them up for some measurements on my PTH1010's. I expect them to be similar to the 476's but we will see.

    Rob
    Attached Images Attached Images  
    "I could be arguing in my spare time"

  10. #10
    Senior Member
    Join Date
    Oct 2003
    Location
    Texas
    Posts
    1,764
    Quote Originally Posted by 1audiohack View Post
    When I finally got the 4338 horns done, the first thing I put on them was a pair of 2451SLís and they sound great. Next a pair of M2 D2ís and the magic is gone. Didnít surprise me at all but I still keep trying to like them.
    I think it was sebackman in that huge M2 DIY thread (the guy who was making the adapters for the M2 horns to use large format drivers, think it was sebackman). He had D2's and swapped in some 2451's. Liked the 2451's better, seems like he went back and forth, at least with measurements, ended up with the 2451s on there if I remember correctly.

  11. #11
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,200
    Hello Mitchco

    I can see why they were well received! I am frankly a bit surprised just how well this driver measures considering how inexpensive it is compared to a 2450! They seem to have done a really good job designing them for lower cost without loosing the performance. That's a 1.5 meter measurement and the top end is much smoother than I expected.

    Worked up a passive network compensation on the 2453H-SL on the PTH1010s. As I suspected these 245X drivers are very similar. Was able to just tweak the the network from the PTH1010/476 combo, remove the highpass network and go from there. This will be crossed at 1.5k 24db L/R active crossover when used in my basement system.

    Rob
    Attached Images Attached Images     
    Last edited by Robh3606; 06-28-2020 at 11:59 AM.
    "I could be arguing in my spare time"

  12. #12
    Member Mitchco's Avatar
    Join Date
    Feb 2013
    Location
    Sunshine Coast, Canada
    Posts
    74
    Hi Rob, excellent! I totally agree, for the cost, they measure very well and certainly sound good to these ears. My measurements are similar.

    Would be interested in your listening impressions once you have everything set up and tuned.

    Happy listening!

    Kind regards,
    Mitch

  13. #13
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    10,295
    Quote Originally Posted by Mitchco View Post
    Would be interested in your listening impressions once you have everything set up and tuned.
    +1

    Hurry up already!


    Widget

  14. #14
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,200
    Quote Originally Posted by Mr. Widget View Post
    +1

    Hurry up already!


    Widget
    LOL I am working on it. Got a comp network built and tested. I hope my terminals come in today forgot I only had 3 need 4

    Took a look at the waterfall plots to see how noisy it is up top looking at the saw tooth impedance plot. Lot better than I expected!

    So far so good!

    Rob
    Attached Images Attached Images     
    "I could be arguing in my spare time"

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Array 880 Listening Impressions
    By Robh3606 in forum Lansing Product General Information
    Replies: 46
    Last Post: 02-07-2014, 08:36 PM
  2. Large format ?
    By richluvsound in forum Lansing Product Technical Help
    Replies: 6
    Last Post: 04-01-2011, 03:05 AM
  3. Large format alnico driver.
    By John in forum Lansing Product Technical Help
    Replies: 43
    Last Post: 03-06-2010, 12:58 AM
  4. Everest Listening Impressions
    By Don McRitchie in forum Lansing Product General Information
    Replies: 84
    Last Post: 01-12-2007, 05:14 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •