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Battle of the polydomes

Discussion in 'Infinity Loudspeakers' started by okeeteekid, Jul 27, 2018.

  1. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    Just got the Genesis titanium domes in,
    1 first off they do not exactly fit in the kappas, bolt pattern is slightly smaller, I had to use a small wooden dowel and glue and hammer it in to fill the old holes in the cabinet, the new bolt pattern was just a hair smaller than the cabinet holes, easy fix no big deal.

    2 firstTest, I used a cap that crossed them over at about 550hz and compared all three domes, the genesis dome is louder than the polydome and the RSDS polydome, this difference in output can be corrected by lowering the L pad on the back of the speaker four or five notches.

    3 The genesis dome has waaay more detail than the polydome and the RSDS, the polydome sounds like it is a slightly muffled when you compare it to the Genesis dome and the RSDS falls in between the two other domes as it has more detail than the polydome but less than the Genesis, I think because the Genesis is a lighter stiffer dome it is louder and more dynamic with more detail, but that does not mean it is better for the aplication.

    4 The Genesis sounds pretty nice so far, piano sound much better and so does guitar strings, the only thing lacking a bit is mens lower vocals and for that matter all lower sounds that can easily be heard in the other two domes, the polydome and the RSDS polydomes are better in that area.

    5 The Genesis blends well with the EMIT'S, now I'm getting detail like the EMIT'S down to 800hz with the Genesis dome, I'm use to the L-EMIM mid bass detail, the polygraph to me is lacking in some detail but is fast, hits hard and is dynamic to makeup for any detail loss, I think if the polygraph had a little more detail it would compliment the Genesis dome better.

    6 The Genesis is definitely a good quality dome but I'll have to do some more listening and testing.
    IMG_0215.JPG IMG_0218.JPG
     
    Last edited: Jul 30, 2018

     

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  2. sagebug

    sagebug Active Member

    Messages:
    105
    Where did you source these? I have one, looking for its twin. Was going to do a custom center channel if I couldn't find another.
     
  3. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    http://www.genesisloudspeakers.com/ you have to tell him it's for one of his speakers or he might not want to sell it to you, I told him it was for an 8300 f, the same driver is used in all their speakers, same model #, I just told him both my drivers were dented, good luck, I was playing around and added a 3 ohm 10 watt resister to the positive wire of the dome and it sounds really nice with the L pad in the normal position in my k9's, too me the driver is louder as confirmed when I ran them with just a 45 uf cap, you could hear that it is louder, the L pad on the back of the speaker to me did more of the frequency response of the driver than lowering it, with the 3 ohm resister in place the k9 sound more like my epsilon.
     
    Last edited: Jul 28, 2018
    Depecheduran and sagebug like this.
  4. Bahamayellow

    Bahamayellow Well-Known Member

    Messages:
    746
    Very interesting. Glad you did the comparison and shared results.
     
    okeeteekid likes this.
  5. jazzmans

    jazzmans Super Member

    Messages:
    2,272
    Location:
    devils playground, NV
    Thanks, okeeteekid!
     
    okeeteekid likes this.
  6. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    Really putting them to the test, a little unfair lol
    IMG_0220.JPG
     

     

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  7. Bahamayellow

    Bahamayellow Well-Known Member

    Messages:
    746
    Got to let us know the results on that one.
     
  8. swechsler

    swechsler Frog Whisperer

    Messages:
    5,003
    Location:
    7th row center
    I did see someone several years ago who actually did replace his polydomes in his K8s or K9s with EMIMs. The problem, of course, is that they're meant to be mounted vertically and there's no room for that (and if it was K8s, that they're meant to be mounted in an open baffle, not a sealed cavity). Couldn't find them with a web search.
     
  9. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    The emim is more natural sounding than the genesis dome, it blends in better with the other drivers, I think the Genesis dome needs a sharper slope/drop off, maybe 24 db per octave and here's why.

    If you compare the way the polydomes sounds to the way the Genesis dome sounds, the polydome and the RSDS goes deeper in vocals than the Genesis dome, the Genesis dome goes much higher in frequency than the polydome does and has more detail than the polydome and Genesis dome is also louder than the polydome.

    To compensate for the Genesis dome being louder I had to add a 3 ohm resister which corrected the Gens output to match the output of the polydome.

    Problem is, when you match the Genesis domes output to that of the polydomes output with the 3 ohm resister the genesis domes lower frequency's get lower output too, meaning that I would of liked to only lower the output of the gens upper frequency's or make it have less frequency extention to better match the response needed for the kappa 9, The Genesis dome also went much higher in frequency than the EMIM, I think the only way to correct this is with a steeper slope/ drop off in the crossover.

    If you just drop in the Genesis dome in the kappa 9 using stock settings, it's way to loud, it gives you the effect of when you raise up a frequency real high on an equalizer, you know that sound, the mid sounds nice but over shadows the rest of the speaker, too me it's missing something, lower mens vocals and warmth that matches the rest of the k9 aside from the emits Lol just my thoughts on the Genesis dome installed in the k9 after comparing it to 3 different drivers, I enjoy listening to my stock k9's for hours on end but with the Genesis dome installed in my k9's I find myself listening for much shorter periods of time, oh well, for me... it's back to the original polydome for now.
     
    Last edited: Aug 1, 2018
  10. 7.62

    7.62 Gearhead Subscriber

    Messages:
    1,558
    Location:
    Las Vegas
    I wonder if it looked something like this...
    IMG_2145.JPG

    Okeeteekid, Lol that's what I call hanging in there !
     
    Last edited: Jul 29, 2018
    okeeteekid likes this.
  11. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    Did 3 quick videos so you guys can hear how the domes compare, in each video every dome plays the same tunes battling it out so you can hear their sound characteristics, I just used a large cap to cross them over at about 550hz so not to damage the domes, I did not use a choke/coil so you could hear each domes frequency extension better, the audio is not the best, I used the wrong camera plus got some fan noise from the CPU next to the drivers.
    Test 1
    test 2
    test 3
     
    Last edited: Jul 30, 2018
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  12. markuus3889

    markuus3889 Diatom, what's that?

    Messages:
    307
    Okeeteekid this is excellent! Thank you for taking the time!

    This is just my opinion but I actually like the original best it seems smoother/less shrill. That may also be why I didn't like the Midwest speaker version much. I've never heard Emims in person so I haven't been spoiled by those yet.

    I'm hoping BobbyD can come through and make proper repros since for me the original material and construction is still the best for my tastes.

    Mark K.
     
  13. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    My thoughts exactly, it seems the Genesis dome goes too high in frequency and the kappa crossover can't tame it, not a steep enough crossover slope or drop off, the other two drivers naturally roll off, the original matches the design of the kappas best.
     
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  14. 7.62

    7.62 Gearhead Subscriber

    Messages:
    1,558
    Location:
    Las Vegas
    Yeah for sure, Thanks okeeteekid for taking the time to do this for all of us ;). I think I prefer driver #2 overall in your testing and great music choices for each test. It makes it easy because it's music I grew up with and am familiar with.

    The original sounds a bit veiled to me and the #3 is kinda shouting/loud.

    What's funny to me. really, they all sound like crap ! Compared to other midrange drivers I've heard, which shows me how little I know about speakers in general because Infinity putting them as a whole sure made some awesome speakers.
     
  15. Bahamayellow

    Bahamayellow Well-Known Member

    Messages:
    746
    Thanks for sharing I was wondering what to do with all my backup drivers from eBay . Guess I will keep them for awhile longer.
     
  16. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    They do sound like crap next to the HE EMIM that I have, I didn't think to test the EMIM up against those domes till I was done and posted the video, how stupid of me Lol, driver #2 is the Genesis, you can hear it's extended high frequency response compared to the other domes, the kappa crossover doesn't have a steep enough slope/drop off to tame it unfortunately.
     

     

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  17. 7.62

    7.62 Gearhead Subscriber

    Messages:
    1,558
    Location:
    Las Vegas
    I have to agree while you were doing it would be neat to hear the HE Emim and even maybe a standard emim for the heck of it,

    So I have to ask, and not to take your thread off track, the L-Emim in your Epilson's is the same type used in the 80-90 Only on a larger scale ?

    And as far as the Genesis goes if you were to use it in the Kappa 9, the potentiometer does NOT calm it down so in order to use it or integrate it into the speaker the complete crossover would need tweaking ? Because of phase and timing.
     
  18. okeeteekid

    okeeteekid Well-Known Member

    Messages:
    825
    Location:
    Northern NJ
    The epsilon mid bass driver is of the same design as the ren 80/90 EMIM but it is larger, 7.5 times larger to be exact.

    As for the Genesis dome..I think to have it work perfectly you would have to tweak the crossover, you definitely need a more drastic drop off slope in the crossover to get it to work, then there is the output of the dome and like you said the timing and phase that the average Joe wouldn't be able to do because you have to be knowledgeable and have the equipment to do it right.

    Don't get me wrong many people would be happy with the way the Genesis dome sounds if they were to just drop it in the k9 not knowing what a good polydome sounds like in the speaker, to me the polydome matches/compliments the k9's other drivers and the k9's crossover is tweaked to make it's drivers sound their best, the parts choosen in the k9's crossover for the polydome compliment that driver, when you put the Genesis dome or any other midrange driver in the k9 those same crossover parts may be making the Genesis dome sound bad as they were not choosen for that driver.

    I got too many domes I don't think I will ever use, time to put them up for sale, including the Genesis dome
     
    Last edited: Jul 31, 2018

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