Take a look at Seas' own measurement of the speaker (the MK 3 version).
http://www.seas.no/images/stories/diykits/pdfdataheet/odin_mk3_measurement.pdf
It should sound a bit too midrange-focused, dont you think?
The main problem with this kit is that the XO dont correct the baffle step quite enough. The series coil should be 1.5 mH, not 1.0 mH, but then the speaker would get 2-3 dB lower sensivity. I think they traded sensitivity for an incorrect tonal balance.
http://www.seas.no/images/stories/diykits/pdfdataheet/odin_mk3_measurement.pdf
It should sound a bit too midrange-focused, dont you think?
The main problem with this kit is that the XO dont correct the baffle step quite enough. The series coil should be 1.5 mH, not 1.0 mH, but then the speaker would get 2-3 dB lower sensivity. I think they traded sensitivity for an incorrect tonal balance.
troels have a ton of seas project , better then Odin that is quite old ..
taste of music ....from troels:
"Before going into details, a little on the sound. To my ears the sound from these nextel coated drivers fall between the SEAS Prestige CA and EXCEL magnesium drivers. This may suggest sound quality inferior to the magnesium cones. It isn't. It's as good as the magnesium cones, only different due to improved responsiveness. I don't think they beat the magnesium cones in terms of neutrality, but these Nextel coated paper cones provide a very neutral, yet vivid sound. The best of both worlds? Well, only your ears can tell."
hope this helps
taste of music ....from troels:
"Before going into details, a little on the sound. To my ears the sound from these nextel coated drivers fall between the SEAS Prestige CA and EXCEL magnesium drivers. This may suggest sound quality inferior to the magnesium cones. It isn't. It's as good as the magnesium cones, only different due to improved responsiveness. I don't think they beat the magnesium cones in terms of neutrality, but these Nextel coated paper cones provide a very neutral, yet vivid sound. The best of both worlds? Well, only your ears can tell."
hope this helps
With massive metal resonance at 5kHz and xo frequency of 2.2khz, the harmonics distortion of W18 would be massive. Such driver should be used under 1kHz or perhaps 1.5kHz with very steep xo and deep notch (active xo).
Perhaps this is what the builders are hearing.
btw. I have Seas L21 with nearly similiar peak, only about 400Hz difference, which is at 4.6kHz compared to W18.
I cross it actively at 1.5kHz and put in very deep, high-Q notch (18db) and the peaks are still there. It is audible.
Perhaps this is what the builders are hearing.
btw. I have Seas L21 with nearly similiar peak, only about 400Hz difference, which is at 4.6kHz compared to W18.
I cross it actively at 1.5kHz and put in very deep, high-Q notch (18db) and the peaks are still there. It is audible.
Last edited:
I think that's a myth and not proven acoustically.
Assume for example, that you cross really high let's say 3kHz and above. Even 5" driver would have beam. 6" would be worse. There will be no smooth dispersion transition to tweeters.
At that range, the distortion would increase as well, and if it was a rigid cone driver like aluminum or magnesium, the breakup will be near and manifest in harmonic distortion, and no notch filter can fix it.
All this, unfortunately can be mistaken in terms of perception as "detail", "bite", etc.
going back to the Odin, the crossover (or overall design) is the issue, not the drivers.
You will surprice that my FR supravox 8" OB do not beam!
my scan 15w/9800 sound a lot better and difference at 2500(18db) then 1700 (18db)and in the past I thinks ,as you ,that low x/over was better and tech correct!
two ways is a compromise ,a lot better 3 ways with small cone mid that do the most...and big bass !! what do 15" with hi qts in OB ....
by the way nice speakers
PS the scan collect dust! no boxy sound forever
Last edited:
8" that does not beam? How is that physically possible? Do you have polar response plot, or is someone telling you that
Yes, higher XO point *could* be better, for example if the tweeter's distortion is high at lower frequency. XO point should be selected with many factors in mind:
- Dispersion pattern of woofer and tweeter at the given point
- Distortion of both woofer and tweeter
- output/SPL goal
etc.
Yes, higher XO point *could* be better, for example if the tweeter's distortion is high at lower frequency. XO point should be selected with many factors in mind:
- Dispersion pattern of woofer and tweeter at the given point
- Distortion of both woofer and tweeter
- output/SPL goal
etc.
The W18 will sound bad at any case if crossed over 1Khz or if with low order xover. My personal opinion is that 700Hz is the maximum freq. for this driver and if used with 4th order eliptical xover and a notch. Its sensitivity is low as well which will force you to use solid state amplification or an expensive tube amp ( 211, 845 and etc. ). It will need impedance correction as well...too much components in the crossover.
If I was you and I was looking at metal cones only, why not to look for a project employing the Seas W22 and a Jordan fullrange for example?
If I was you and I was looking at metal cones only, why not to look for a project employing the Seas W22 and a Jordan fullrange for example?
I will kill my mate that he never did the cabinet for the project I started for him back then.
Aluminum Bliss
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.