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  1. #406
    Senior Member Anti K's Avatar
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    Quote Originally Posted by Ian Mackenzie View Post
    My writing style has been compared to an American writer William T. Vollmann.
    My style is kinda American writer (if You like it has to be American, and writer) John Irwing.
    In first part given light - by first impressions - hints and light sentences make sence in last quarter, where fragments gather together like puzzle. A very calculated puzzle.
    Jep, Irwing is a good example, more respect because of his life before he became a writer.

    Quote Originally Posted by Ian Mackenzie View Post
    do you use a fine tip brush as it were or do you use fence painting brush and flick paint everywhere
    I usually go while fullmoon to the crossroads in the middle of the night and pee to the southways

  2. #407
    Senior Member ivica's Avatar
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    Quote Originally Posted by Anti K View Post
    .....

    And mostly owners of these beasts fancy the fast mid...
    Despite, as funny it is, the huge system is all built across one MID!
    Which is - logic - human listen human voice best.
    Plus, yeah, just some ways above and (some) way below MID freguencies.

    Only topic here is - and I admit it - am I able cross them right away. Am I able to make in the future phase linear.
    If not, I buy the knowledge in.
    __________________________

    Now I'm on second circle and trying avoid old mistakes - shelfs covered with no-needed drivers. But seems cannot totally avoid this , AGAIN.

    I mess up at moment with Lens integration.
    But the test-boxes will be there !

    Went though quite punch of data;
    Found one 18s-12NDA610 is like clone of JBL-2202H on paper. Seems very much I order these as well... for testboxes or/and for shelfs
    Hi Anti K,

    May be Bayma 12P80ND , 10Mi100, 12Mi100....
    or eve BEYMA LIBERTY-8
    https://usspeaker.com/beyma%20liberty-1.htm

    Regards
    Ivica

  3. #408
    Senior Member Anti K's Avatar
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    Meanwhile of sawing and milling cabs.

    Going through data found MID and LOWs, which in certain cabs (all accomondates into Everests), have from 125 to 420Hz constant delay difference ca 0,1ms (ca 10 deg @ 300Hz) in region from 125 to 420 Hz. Theoretically, delaying one 0,1ms, filtering in the middle of this region, the MiD and LOW should cover each other quite well.
    Same delay difference 0,1ms / both sealed , or both vented.

    Some combo bended well as MrWidget did, certain 'stellar' MID was in vented (rear port, tuned low just for correct phase) and LOWs in sealed. But felt, it keeps me 'narrow playground'.

    Founded driver models didn't finally surprised me at all, nothing new under the sky. Got used to, within half century, the stellars on paper are not too often stellars in reality.
    Per channel radiating :
    500+cm2 - MID / 2,5 octaves
    1500+cm2 - LOW / 2 octaves
    2500 cm2 - Subsonic / 1,5 octaves
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  4. #409
    Senior Member ivica's Avatar
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    Quote Originally Posted by Anti K View Post
    Meanwhile of sawing and milling cabs.

    Going through data found MID and LOWs, which in certain cabs (all accomondates into Everests), have from 125 to 420Hz constant delay difference ca 0,1ms (ca 10 deg @ 300Hz) in region from 125 to 420 Hz. Theoretically, delaying one 0,1ms, filtering in the middle of this region, the MiD and LOW should cover each other quite well.
    Same delay difference 0,1ms / both sealed , or both vented.

    Some combo bended well as MrWidget did, certain 'stellar' MID was in vented (rear port, tuned low just for correct phase) and LOWs in sealed. But felt, it keeps me 'narrow playground'.

    Founded driver models didn't finally surprised me at all, nothing new under the sky. Got used to, within half century, the stellars on paper are not too often stellars in reality.
    Per channel radiating :
    500+cm2 - MID / 2,5 octaves
    1500+cm2 - LOW / 2 octaves
    2500 cm2 - Subsonic / 1,5 octaves

    Hi Anti K,

    I think that You are too occupied about theoretical investigation about "expect-able" responses. But my experience is that the real would be very different, so if You want to cancel (as much as possible) comb filer effect due to the drivers delays, I would suggest to apply some kind of DSP supported digital network, where quite precise delay can be implemented, as "group delay" (phase response first derivative) can be mainly implemented with the time delay, but even more more complicated phase compensation (depending to the user supported network interface).

    Regards
    Ivica

  5. #410
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    Hi Anti,

    Those curves in your post illustrate the phase shift also know as group delay of a driver at the end of its pass band.

    Ideally if your drivers have sufficient overlap the crossover points should be within the pass band of the driver. There are other reasons for this:

    Smooth driver crossover region
    Avoid driver / sub enclosure resonance
    Reduce X Max diaphragm displacement
    Reduce distortion

    A driver will work in its optimum range if you observe these criteria. At high drive levels it becomes subjectively more important because you are taking the driver close to limit of its dynamic capacity.

    In a sealed sub enclosure you can adjust the volume for a specific Q. This can be a nominal 0.707 Butter-Worth or a lower Q such as 0.577 which is critically damped and will improve the dynamic step response of the diaphragm. Typically a lower Q sealed enclosure is a little larger.

    The group delay more likely to cause audible crossover artefacts in midrange where wave lengths are shorter and the distance between the midrange and the horn are separated by more than 1/2 a wavelength. You can modify phase response in DSP.

    Another point to consider is the importance of inductance of the voice coil.

  6. #411
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    A moving voice coil in the magnetic gap causes modulation of the voice coil inductance.

    That causes distortion which is bad. The louder the driver goes the worse the distortion. Some drivers have additional elements in the magnet to help control the distortion such as shorted turns but this can cause peaking in the response at high frequencies. So you will need to smooth such peaks in the response with your crossover design.

    As the driver goes louder the temperature of the voice coil goes up. This increases the dc resistance and reduces the dynamic loudness of the driver call power compression.

    Most of these things are more likely to be subjectively audible at louder volume levels. This is why some loudspeakers are clearer than others.

    Btw 18Sound make a very good differential drive 12 inch mid bass driver.

  7. #412
    Senior Member Anti K's Avatar
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    Ian, first of all I want to say - I value Your theoretical knowledge very much, no matter what. I worship science.

    Quote Originally Posted by Ian Mackenzie
    A moving voice coil in the magnetic gap causes modulation of the voice coil inductance
    Yes, this is how it works, just simple physics. Thanks to this phenomenom basically Nikola Tesla electrified the planet. Move seriously big cone and switching incandescent bulb to wires of VC, lamp switches. El.magn field causes moving, while movement causes el.magn.field (which works against the original signal ...)
    BMS has even 3 short ring and has, yes , peaks upper there. DSP makes them flat with ease. But I'm worried with BMS next things You also describe here...

    Quote Originally Posted by Ian Mackenzie
    Btw 18Sound make a very good differential drive 12 inch mid bass driver.
    12NMB1000 has (D sibling of ceramic ; at least one of) the markets highest Bl, exellent low Le and insanely high (my personal 'bias') Qms. If that is what You mean.
    At least, it's only one with that kind of combo of features in same package. Tremendous power handling. Seems too good to be true.
    But it has 4'' VC
    18Sound have ISV-design voice coil, what it that? As much I understood - two layers on each other. How it augments heat exhaust, my brain doesn't calculate.

    JBL's DiffDrive (two poles on same axis with reasonable distance from each other) and benefits coming from that stucture are very understandable for me. And reasons You pointed out, heating and rise of resistance caused for that are more than understandable and that's why I fancy JBL. There is no better heat management motor I know. Magnet is inside of VC and 'heatsink' , the huge whole basket (even cone blows on basket walls and cools it!) , cool tube is close-close surrounded the VC! Magnesium alloy has 10X better heat conductivity than steel...
    It's brilliant mechanics!
    It doesn't mean I want to say JBL makes best mid... their MIDs today are for PA.

    However, if people already pray for lazy 140gram 2216Nd , then hell, same motor structure with basically same Bl but with 2X lighter cone should be way faster!? But funniest thing is, nobody didnt use 2261, or 2262 - in JBL forum. Yes, 2216 has painted gasket, black sounds better

    18Sound 3'' VC models 12NDA610, 12ND830 are excellent on paper.
    12NDA610 is basically like clone of JBL2202 (just 18Sound has 3'', JBL had 4'' VC)

    Quote Originally Posted by ivica
    I think that You are too occupied about theoretical investigation...
    If You think so. Just, imagine, buy something and ... for example 18 Sound has 3PCS of quite acceptable drivers on radar. Beyma has 2 for me. BMS has 2PCS
    How much , You think, is OK to buy them, just like that, together and make side-by-side tests. And get serious understanding takes moths, if not half year.
    And, OK, if I do that, then what I'm going to do with the rest of them... :-). And one more thing - to get full understanding, there is need for sure a pair...
    So, starrt with which one? With dinosaur Liberty you suggested?


    Quote Originally Posted by ivica
    I would suggest to apply some kind of DSP supported digital network, where quite precise delay can be implemented
    I will. I think 15ms delay possibility is more than enought to align whatever drivers together ... in some POINT.
    But thing is, Delay is constant! Driver's phase changes. The wider drivers have parallel phase graphs, before and after the crosspoint, smoother is overlap.
    So implementing certain delay for one driver, to make it bang in-phase with another, at ecaxt crosspoint, is not a magic at all. To EQ out some peaks and holes with DSP is piece of cake.
    Magic is, to keep two drivers in-phase wider area around the crosspoint...

    Here is a overall question: say, filter is 24dB/oct. At exact crosspoint both drivers bang indeally in-time zero degrees off-phase. Now, a octave higher, the lower driver 'screams 27dB quieter'. How many degrees it could be off-beat, it doesnt sound ugly yet?

    We talk about harmonic distortion. In the other words, we can imagine it as a additional rookie driver screams simultaneously.
    'Endlessly' phase linear is fullrange or FIR.
    Both I pass today. First do not even comment, second one too complicated to me yet. But DSP will be future-proof for FIR.

  8. #413
    Senior Member Anti K's Avatar
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    Quote Originally Posted by Ian Mackenzie View Post
    Btw 18Sound make a very good differential drive 12 inch mid bass driver.
    !?

    https://www.eighteensound.it/en/technologies

    12NTLW3500 is something new
    https://www.eighteensound.it/en/prod...0/8/12ntlw3500
    Can You please give a link to this 12'' keepeing in mind ; if that's not I mentioned just above.

    ivica, I'm a neo-junkie, don't fancy horses, (very) old women, Chanel No5 ... and historical drivers
    Here is a reason as well I had just 2 horn on list, too: M2 or 4367. Last one fit just perfectly with my current project. All others wasn't even options.

  9. #414
    Senior Member Anti K's Avatar
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    Quote Originally Posted by ivica View Post
    I think that You are too occupied about theoretical investigation about "expect-able" responses
    It's easy, Yo.

    #yougotalltheanwers
    #veryexperiencedpeople
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  10. #415
    Senior Member Anti K's Avatar
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    4350/55

    4350/55 is to me the coolest speaker ever made.
    The steps between ways, radiating surfaces according to steps. No-matter-what-engineering!

    ( let leave people with screaming wifes, children and dogs - their opinions about beauty and size doesn't matter )

    Just trying reincarnation it in new form - simple as that.

    When Lens are done and I'm still stucked in MID, then just kick JBLs 1x2262 and 2x2265 in there and done.
    They both do, when ways are separated (70-270 / 270-1100Hz) their own part better than 2216Nd.

    While MID lies in 1,5 ft3 box, rear vented (can be closed whenever) I can basically kick in there whatever Driver.

    2x2265 likes Everest cabs more than 2x2216.

    (no arque, 2216 outperforms when needed just ONE for EVERYTHING up to HF)

  11. #416
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    https://www.eighteensound.it/en/prod...0/8/12ntlw3500

    While Jbl offer some differential drive transducer as spare parts they DO NOT provide data

    18Sound provide Data

    https://www.eighteensound.it/en/prod...0/8/12ntlw3500

  12. #417
    Senior Member Anti K's Avatar
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    One more thing

    Was time to get married. Boy had tree girls, one wise, one beauty and one was kind.
    And of cause he married to girl who had ... biggest t***s

    Going through very big circle found out, 18Sound has the Beastest Best, the Newest New. And it's very much like ... JBL 2262H.
    What I was told already many posts ago: I think I found, and posted phase garps as well.

  13. #418
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    There is no perfect ‘one solution’ btw.

    To avoid spirally into nervous breakdown and disappearing back up your own clacka why don’t you put what you have together and try it?

    That is your starting point.

    This is the thing.

    It’s not going to be the driver you finally chose after months of nail biting that makes it sound good. But how well you implement your project. Your implementation will swamp the driver differences 20:1 in terms of any subjective assessment.

    Attempting to squeeze a bunch of drivers into a pre determined box design is your biggest challenge and will be the pivotal deciding factor on the success or failure of your efforts.

    We have lots of tissues for the tears when the whole thing turns to shit and it probably will to start with. That is when the real work starts.

    Did you know the greatest forum minds including Mr Widget came to the same conclusion when they got hold of some start of art drivers from JBL a long time ago. The entire mess never got finished.

  14. #419
    Senior Member Anti K's Avatar
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    Quote Originally Posted by Ian Mackenzie View Post
    There is no perfect ‘one solution’ btw.
    / ... /
    We have lots of tissues for the tears when the whole thing turns to shit
    Totally agree.
    Most of drivers ARE shit, rule Nr1, and only way is to avoid them...

    What is important here, it comes into my mind the more I dig in, the more produsers all aroud 'launch' their new models, JBL was lite years ahead with this DiffDrive.

    When putting and putting demands on driver - silently, loudly, crazily, long, acoustical, synthesized, stone-age-rock, progerock, orchestral, brass, female, male. Bali-ting-tong-nomusic. Day-by-day, years ... then, there is no perfect ‘one solution’ , but somehow just leaves only one on table...

  15. #420
    Administrator Mr. Widget's Avatar
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    Quote Originally Posted by Ian Mackenzie View Post
    Did you know the greatest forum minds including Mr Widget came to the same conclusion when they got hold of some start of art drivers from JBL a long time ago. The entire mess never got finished.
    I assume that is a reference to the train wreck also known as Project May. I would submit that project failed due to too many cooks being in the kitchen. The combined forces of many talented individuals proved to be less than the sum of the parts.

    Additionally the “client” wanted a version of the K2-S9500 with a beautiful wooden horn... however we were derailed by the riches provided by well meaning support at JBL. Essentially the components of the K2-S9800 which were generously provided were ill suited to the K2-S9500 layout and aesthetic.

    Fortunately after the train wrecked and the dust settled, the “client” ended up getting a pair of very fine sounding M2s.

    To the point of this thread, after a thorough theoretical exploration, be prepared to throw out your initial design once the prototype is begun. You will learn that reality and theory are not in 100% alignment. You will have two choices. Change direction with a modified version of your initial dream, or live with a system that matches your dream but is not the best possible solution.


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