Yeah! That particular 10 inch has some huge problems over 300/400Hz big peaks of at least plus 8dB, and that is from the Jaycar graphs with 3rd order smoothing applied.
There is a 8inch Diatone driver on Ebat at the moment that should make a good OB mid-range, I'm looking but no intention of bidding
There is a 8inch Diatone driver on Ebat at the moment that should make a good OB mid-range, I'm looking but no intention of bidding
Ultima GTR said:
Don't be! I'm sure plenty people will think I'm crazy to buy $350 worth of drivers without any box
. I mean that could easily buy a monitor audio BR2 right ? 
Moondog55 said:
Strange enough mine measured well nearfield. The dipole peak from about 1m is at around 490Hz though. Did you measure on open baffle, as this would be that peak and not necessarily th driver's response?
I should have measured its 2nd and 3rd distortion. Maybe later just for fun.
Cheaper mids that interest me are the 10" Celestion in the Pro range, not the guitar range, and the TF0818 which is an 8" unit. It seems quite flat but I cannot find an Australian dealer for them with online information and prices. The seem to retail for 25.00 pounds upwards in the UK. I have asked whether other member have heard them but I guess the answer is no as there have been no responses. The ferrite 10" looks on paper to be smoother than the the neo one.
jamikl
jamikl
I didn't measure these, still haven't got a calibrated mike or decent sound card, just took the published Jaycar stats with the usual cup full of salt.
But when I used them full range I found them vry forward and "Shouty" something I usually associate with a big peak around 1200/1500
Overall I'm happier with the 12s.
My next experiment before using my P-13s was going to be a 4 woofer trial using an 8inch coral as the mid
But when I used them full range I found them vry forward and "Shouty" something I usually associate with a big peak around 1200/1500
Overall I'm happier with the 12s.
My next experiment before using my P-13s was going to be a 4 woofer trial using an 8inch coral as the mid
Some finishing touches tonight on the xo... added Linkwitz transform circuit. It is now -3db at 20Hz. Very satisfiying LF . Unfortunately I don't know how to measure farfield LF to confirm/show off
I'm still struggling with mid-tweeter crossover sound. It is time aligned, measured flat, etc. But I still think it's unrealistic/not very smooth. What could be wrong here? Is this an unresolvable problem due to physical difference of 5" mid and 1" tweeter ? Is this why people keep insisting to use full-range???
What I want is when I turn the tweeter up so slowly the sound becomes "one". Not dull, bright, or "audibly separate".
Lots of Orion review said that midrange-tweeter transition is very smooth. What is the factor here? The XO looks to be typical stuff. Could the Millenium tweeter be really that good?
. Unfortunately I don't know how to measure farfield LF to confirm/show off I'm still struggling with mid-tweeter crossover sound. It is time aligned, measured flat, etc. But I still think it's unrealistic/not very smooth. What could be wrong here? Is this an unresolvable problem due to physical difference of 5" mid and 1" tweeter ? Is this why people keep insisting to use full-range???
What I want is when I turn the tweeter up so slowly the sound becomes "one". Not dull, bright, or "audibly separate".
Lots of Orion review said that midrange-tweeter transition is very smooth. What is the factor here? The XO looks to be typical stuff. Could the Millenium tweeter be really that good?
I did more investigation on the mid-tweeter transition sound. More measurement near, far etc. and there seems to be nothing wrong.... until somehow I realised that those measurements are on-axis and I am listening off-axis due to the height of the tweeters.
Sure enough I played pink noise and from the listening position moved my head up and down (the wife was amused). The tweeter beams and from the listening position the "height" of the sweetspot is only 10cm or so, which is not much at all. Where my ears would be 20cm lower sitting and seems to be in exact position in a null lobe. Once identified it is easy to notice this in music playbacks.
I will need to cut shorter baffles to prove this finding, and unfortunately this will not allow the 3rd woofer.
Sure enough I played pink noise and from the listening position moved my head up and down (the wife was amused
). The tweeter beams and from the listening position the "height" of the sweetspot is only 10cm or so, which is not much at all. Where my ears would be 20cm lower sitting and seems to be in exact position in a null lobe. Once identified it is easy to notice this in music playbacks.I will need to cut shorter baffles to prove this finding, and unfortunately this will not allow the 3rd woofer.
But think, it would be WWMTW or WWTMW
Altering the position of the tweeter brings a change in the degree of tilt from positive to negative looking at the centre-line of the drivers, so the position of the sweet spot may change.
The "cook-book" has a section on this aspect of cross-over design but my copy has been misplaced.
my experience has been that it makes little practical difference but then I make mainly MTM designs for the greater directivity
Altering the position of the tweeter brings a change in the degree of tilt from positive to negative looking at the centre-line of the drivers, so the position of the sweet spot may change.
The "cook-book" has a section on this aspect of cross-over design but my copy has been misplaced.
my experience has been that it makes little practical difference but then I make mainly MTM designs for the greater directivity
Thanks.
As this is OB I'm trying to think of of from the all-important polar response. So WWWTM response would be something like wide dispersion - then narrows - then wide again reaching the midrange. Something like an "hourglass" perhaps ?
Where as WWWMT would be something like a sharkfin or half a surboard...
I think this is something that I really need to try physically by cutting new baffles.... hmmm router dust mmm..
As this is OB I'm trying to think of of from the all-important polar response. So WWWTM response would be something like wide dispersion - then narrows - then wide again reaching the midrange. Something like an "hourglass" perhaps ?
Where as WWWMT would be something like a sharkfin or half a surboard...
I think this is something that I really need to try physically by cutting new baffles.... hmmm router dust mmm..
Okay... it's been just over 3 months since I completed these speakers. From the start the compromise is always there, the P13 being acoustically too small for 30cm baffle, violating the < 2 * mid diameter rule.
The measurements given in previous pages shows uneven response in 1-2kHz region. This manifests in midrange quality. I've tried may approach including multi-eq/notches. It did not work.
Thus it is declared that this design is a dud! It has it's quality, namely powerfull bass, and the usual Dipole qualities, but it's not "the last speakers". Too bad, we've enjoyed so many good times together...
Stay tuned for further attempt
The measurements given in previous pages shows uneven response in 1-2kHz region. This manifests in midrange quality. I've tried may approach including multi-eq/notches. It did not work.
Thus it is declared that this design is a dud! It has it's quality, namely powerfull bass, and the usual Dipole qualities, but it's not "the last speakers". Too bad, we've enjoyed so many good times together...
Stay tuned for further attempt
stop listening to music and start tinkering! I look fwd to the next installment. Its certainly been fun watching all of your projects. I cant help thinking there is more that can be done with MJK's h frame design with perhaps a triangular baffle on top fot either a fullranger or MT like Rudolph on AC is doing. But then again I'm tossing up btw this and another design so I understand Happy hunting
cheers fergs
I look fwd to the next installment. Its certainly been fun watching all of your projects. I cant help thinking there is more that can be done with MJK's h frame design with perhaps a triangular baffle on top fot either a fullranger or MT like Rudolph on AC is doing. But then again I'm tossing up btw this and another design so I understand Happy hunting cheers fergs
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