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  1. #16
    Senior Member Anti K's Avatar
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    Quote Originally Posted by Champster View Post
    Last edited by Anti K; 01-27-2021 at 01:42 PM. Reason: the graph

  2. #17
    Senior Member pos's Avatar
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    Hi Andy,

    If you want more SPL another solution is to use two 2216nd per speaker, in a 2.5-way arrangement similar to the 4435 or DD66000:

    http://www.audioheritage.org/vbullet...l=1#post401465
    This is a modular design, with two boxes. The two grills are the original M2 ones and do fit the waveguide on both sides.

    The EQ/filtering is super simple and can be adapted from the M2 settings: you simply have to alter the shelving filter a bit and add a 95Hz 1st order low pass on one woofer and you are done.
    http://www.audioheritage.org/vbullet...l=1#post405011
    This can even be done with a simple cap in front of the amp, no need for extra DSP power.

    Compared to a 2216+2269 it is a more elegant solution, IMHO, and you get to use the 2216nd for its indented purpose.
    You get a better phase response out of the box (no more subwoofer crossover), and a chance to trigger room modes from two different locations (per speaker) in the range where the two woofers play together, which is of course a good thing if you want to get an even response at different locations in the room (vertically in the example above, which is often the important plan to consider for home use). This might be the single most important benefit of that design.

    You also get +6dB of SPL capability in LF compared to a single 2216. I don't know how this compares to a single 2269 for a given box size and distortion limit (ie not max excursion).
    You probably get a lower power compression / thermal distortion (namely dynamic!) with that special "TCR" VC material the 2216 is using.

    At this point the weak point in term of SPL might end up being the compression driver on that wide and constant directivity horn.
    A 4" Be diaphragm might be a good choice there compared to a SL Ti as it has a higher mass breakpoint frequency, which results in more SPL capabilities above ~1.5kHz : http://www.audioheritage.org/vbullet...7&d=1314552764

    I don't know how it compares to a D2430K in that regard though: this one has two VC and is meant for serious SPL...

    As a side note, if you buy a 4" diaphragm you might want to choose a 16 ohm one, as it will be a better match for most amps out there in terms of noise, distortion, and power.

  3. #18
    Administrator Robh3606's Avatar
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    Regarding XO there are really not any alternatives to DSP. JBL 4367 are passive but to get to that level in a DIY is probably very difficult. Mind that JBL even had to make a different WG to pull it off.
    Hello Rob

    The M2 waveguide with a 245X/476 is actually very well behaved. A passive network is certainly a possibility providing you want to put the work into it. Agree that DSP is a lot easier and quicker to implement but it is entirely possible. Not sure about a passive with the 2430.

    4''Be / M2 lens.
    2216 / closed box ca 2 cubic feet.
    Hello Anti K

    Look real hard at using Be option. All of the Be roll off above 10K. The MG doesn't and the coated Ti don't but the Ti is not as clean 10-20K

    2216 in a closed box?? Just add a bit of EQ and they really don't need a sub.

    Rob
    "I could be arguing in my spare time"

  4. #19
    Senior Member Anti K's Avatar
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    IT'S A DISCUSSION, OK. Not argue - for my side.
    Saying that because I have respect to all of You senior members here, have read what You know and what You have done...




    Quote Originally Posted by Robh3606 View Post
    Look real hard at using Be option. All of the Be roll off above 10K.
    DD66000 and DD67000 use 4'Be and they are crossed at 20kHz. Above (!) that comes UHF...? And passively, hell, it's a science!
    I plan make it make active and 4'Be cut of with LP filter (or Dirac Live) somewhere 16kHz - where the dia may act not quite well anymore.

    Question here is maybe more, like, philosophical? One point of view is to make 'perfect' graph +/- 0,5dB : science. Like You do here, clones and stuff.
    I have target to make them to myself - for listening :-)
    Knowing, at age 50 I do not listen much above 15kHz (and my son's cats hates these ) but I DO ENJOY 'cristals' (you know the sound knocking with fork to glass of champagne);
    percussions, brass...
    As the Beryllium is lighter than Aluminium and tighter than Titanium - and cannot forgive myselt if I refuse Be...
    Question only is: or 476, or 2450/2451 core rebuilt (new back cap with better damper, maybe longer throat with 1,4' hole, have to measure then), or just simpliest way just purchase radian 951
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  5. #20
    Senior Member macaroonie's Avatar
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    Anti K , something that might help you with construction.

    Baltic Birch plywood can be had with pre formed curves. Think of drum shells.

    http://www.aitwood.com/StoreFront.As...180%20degrees)

    http://www.aitwood.com/StoreFront.As...180%20degrees)

    These folks are in California , I couldnt tell uou if they are doing the forming themselves but since you are in Estonia you may be able to find some supplier in your part of the world.
    Good luck with your project.

    M

  6. #21
    Senior Member srm51555's Avatar
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    Quote Originally Posted by Robh3606 View Post

    Look real hard at using Be option. All of the Be roll off above 10K. The MG doesn't and the coated Ti don't but the Ti is not as clean 10-20K
    I never got my 2450sl's with be's to sound right, even though they measured ok. I ended up going with the same route as sebacman with much better results.

    Thanks,
    Scott

  7. #22
    Administrator Robh3606's Avatar
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    Quote Originally Posted by srm51555 View Post
    I never got my 2450sl's with be's to sound right, even though they measured ok. I ended up going with the same route as sebacman with much better results

    Hello Scott

    Did you stick with the SL's?

    Between the roll off and the DI changing on the horn the power response can take a hit. What I think is happening is instead of the continuation of the gradual roll off you get an audible step like drop off in the last octave in the room. I had that issue 2435'435Be in my active set-up on PTH1010's. The measurements didn't look bad at all but just didn't sound quite right. Had to redo the compensation networks to get out more last octave of them. Then they were good!

    The SL's/Mg's are rising or linear and not falling so they work out quite nice using a passive comp!

    Rob
    "I could be arguing in my spare time"

  8. #23
    Senior Member srm51555's Avatar
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    Quote Originally Posted by Robh3606 View Post

    Did you stick with the SL's?
    I did. It's the best sounding combination I tried and ironically the cheapest. After I got it to sound correct, I swapped systems out to workout an older amp. I really appreciate sebacman's threads on his waveguide work. I wanted the be's to sound right but it just didn't happen even as good as it measured

    Quote Originally Posted by Robh3606 View Post

    The SL's/Mg's are rising or linear and not falling so they work out quite nice using a passive comp!

    Rob
    Yup, they behave quite nicely. EarlK took some data found in your and sebackman's thread and was nice enough to make a starting point schematic on building a passive crossover using the 2451 with 2450sl's that I'd like to get to some day as well. This may have to wait now after Thomas's post of the dual 2216nd's, since I do have a pair laying around waiting for a project.

  9. #24
    Member sebackman's Avatar
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    Dual 2216's would be a very good combination and very loud. Enough LF to kill a small Rhino at 20 feet... :-)

    I agree with all above, to go dual 2216 as opposed to a built-in 18". If you want/need the extra power I suggest stay with one 2216 and build 4 stand- alone SUB18 clones (no need for 2269 in this application to save a few $), one on the middle of each wall and XO real low (<60Hz). Harman has posted a SUB evaluation doc, pls see link, that is good reading for everyone contemplating or using subs.
    Microsoft Word - whitepaper10.doc (harman.com)

    Just a few comments. The older WG's are not very similar to the newer (VTX F12, M2 aso) The newer does behave much better upwards. They may look similar to the PTxxxx but the do not measure or sound the same. I have not tested the 4367 WG (it is so wide) but I do think it is available.

    I agree with Scott, I never got the two-way to work with Be's even if I always use a BSS DSP. Theoretically I can compensate for the drop in UHF, but it does not sound as relaxed as with the 045's. I bring them in from about 10k as it seems to give a more agreeable beaming pattern. All drivers has their own identical amp channel.

    I never got any of the 243x drivers to work on the M2's or VTX's WG's (Be or not). The phasing plug or exit must be different. 2453 does not work right out of the box either. The exit is different and need a spacer between the driver and WG to work. I think I have tried 2452's also in th epast but did not get the same result as the 2450SL/2451. Need to dig in the files if of interest. Most of the 2450SL/2451 driver/dia combinations I do have in the shop.

    The subjectively best combination I have tested so far are 2451 cores with felt back-caps and 475Nd diaphragms. I know, I know, the 2451 and 2450SL cores should sound the same, but they don't on the M2. And all the SL diaphragms should also sound similar, but guess what, they don't. Small differences but audible side by side.

    I have no idea why the combination 2451 core with 475Nd dia's work so well on the M2 but they measure smoother and sound more "relaxed". Very similar to the Be's actually and especially notable on piano and female voices. And that comes from someone that hate feelings based reviews. My somewhat bombastic motto is always, if it measures right it sounds right.

    All these driver/dia combos can be EQ'd with a DSP to measure very well but stil sound slightly different. It may well be that age has killed my hearing or my preference is damaged by my Genelec references :-) . -And I think a fully active M2 setup does sound very good indeed.

    I use 2451 SL's on VTX WG's in a two way system, or quite a number of systems as they sound so good and can be made reasonable small compared to M2 based designs, and 2451Be's with 045's in the main system.

    I do have two brand new NOS 475Nd dias left and a set of M2 horn on order so who now what is next.

    Knowing what I know today I would not have bought Be dias. I have put many additional hours to get the 3-way to work in comparison to the 2-way, even when using a clone of the K2 S9900 UHF setup. I would go SL any day of the week, just as Scott points out, to avoid the extra work with getting 3 drivers to get along with each other.

    Enough rant. Sounds like a fun project

    Kind regards
    //Rob
    The solution to the problem changes the problem.
    -And always remember that all of your equipment was made by the lowest bidder

  10. #25
    Senior Member jmpsmash's Avatar
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    Quote Originally Posted by sebackman View Post
    I have not tested the 4367 WG (it is so wide) but I do think it is available.
    Where to find the 4367 WG?

    If available, it will be easy to make a 4367 clone with the 2216ND1 and 2430K also available. There are no plans per se, however, the white paper has a internal diagram and detailed description of the construction. crossover schematic also can be found here.

  11. #26
    Senior Member grumpy's Avatar
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    2269H

    diameter: 18.25" 464mm measured/confirmed same as 2245 spec
    flange depth: 7/16" measured
    depth (12.5") from online spec
    bolt circle diameter 17 3/8" 441mm from 2245 spec
    baffle cutout 16 13/16" 427mm from 2245 spec a pain to measure directly/accurately, but maybe I'll do the circumference and some maths or find a big set of dividers


    Edit: baffle cutout spec is fine. 429mm would be generous... a very small chamfer would accommodate the frame/flange radius if needed. Front of flange to rear of driver is indeed 12.5"
    Last edited by grumpy; 01-29-2021 at 03:53 PM. Reason: confirmed the rest of the measurements.

  12. #27
    Senior Member Anti K's Avatar
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    Quote Originally Posted by grumpy View Post
    2269H
    My tape measure isn't metric, but if you go 1mm over the exact conversion for clearance, you should be good.
    Thanks grumpy for the measures!

    What sebacman made, is superior, for sure. There is SO FEW people out there who are able to do something with own arms. To finish things, even the back side of product...
    I like the concept: 4'' dia with M2 lens + 15'' low. Because IMHO proper 15 'sings right' below the CD part (I have 4429 at moment and I miss the authority of 15''.)
    ___________________

    My project and 'philosophy' :
    Why 'torture' same woofer with so much of octaves; 6-7 octaves simultaneously?
    Why not to give lowest octaves to handle for the bigger boy like 2269, to what it's intended to. Cross 60...80Hz and below.

    Did You even try to make two things simultaneously - drill a hole to wall with left hand and paint the wall with right hand same time? :-)

    If 2216 is right now 'busy' with lowest part of male and suddenly comes in some a synthesized waves at 30hz, and thousands of another el.mgn.waves , simultaneusly...
    Logic says, if cut of some part from low end, it 'releses' lot of energy and makes easyer to deal with higher waves.
    When I started my first projects when I was 14, remember one rule - leave one woofer ca 3-4 octaves, if You can...

    So: my discussion is: (not a argue),
    why 2216+2216 is better than 2216+2269 ?

    According what I have in mind:

    - just want to pay attention, the listening room would be a'bit bigger than usual living room. It's a lounge area of production plant. Picture below.
    Red line is planned thick curtains. Green arrows direction of sound (there is a quite damped wall behing the speakers). Orange area would covered with thick carpet.
    Room is 4,5m high, 40 metres long...
    The lounge (listening area) would be some 8x8 metres, covered with carped in the middle and surrounded with thick curtains.
    I thing if I'm sitting in this geen circle, curatin behing me, basically like open air situation...

    - With no exceptions I read everybody says, the M2 is good. Very good.
    And JBL made a SUB18 too.
    Why they made it?

    - SUB18 is a box and a 2269. Right? If I take now a pair of M2 and and a pair of SUB18 (pair, because room is big) , like they are, originally, then everything is OK. Right?

    But if I take lot of, for example, epoxy glue and connect M2 and sub18 together, the only difference I see : it's impossible to transport these two items separately, never, anymore :-)
    So, how does it concern the sound?

    Basically, my plan is 'glue' them together, simple as that!
    And yes, 4'' dia instead D2.
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  13. #28
    Senior Member jmpsmash's Avatar
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    You have a very nice room. Very lucky to have such a huge room. But even with huge room, there will be room modes to deal with. And from my experience dealing with a much worse room than yours, you might find the low low frequencies need a different treatment than mid low frequencies.

    You might end up finding that the "SUB18" are more suited to some locations in the room in order to deal with room modes, but these locations won't be ideal for mid/high frequencies.

    So if you have the option, separate out frequencies below 150Hz and have the "SUB18" handle them. and then place your "M2" in places where it will form a nice stereo image with the mid/highs.

  14. #29
    Senior Member 1audiohack's Avatar
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    Hillbilly Caliper

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

  15. #30
    Senior Member macaroonie's Avatar
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    Hey billy bob , what be 17 13/16 ? Is that hogs ?

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