I just picked up a pair of Thor speaker cabinets, wired and stuffed - just no speakers inside. I want to do an MTM style of course, but what other drivers can i use besides the SEAS Excel? Looking to spend $500 or so...
I dont really want to break the bank - do you have any sugestions....
Thanks in advance
Mike
I dont really want to break the bank - do you have any sugestions....
Thanks in advance
Mike
The SEAS THOR KIT uses the SEAS Excel W18E001 Magnesium Woofer and the T25CF002 Excel Millenium Soft Dome.
I'd think you could substitute the cheaper Prestige ER18RNX and the T25CF001 Soft dome.
The 90dB 110mm Morel CAT 328 might have enough output too.
http://www.falconacoustics.co.uk/drive-units-1/morel-speakers-drive-units/morel-cat-328-110-tweeter.html
You'll need a notch at 4.8kHz on the woofer, but then the Thor has one similar : L2,C1,R1 on the Thor schematic anyway!
Alan Yates' Laboratory - VK2ZAY's Engineering Calculators - LCR Resonance
Looks doable to me. Doubtless a bit of fine tuning needed.
I'd think you could substitute the cheaper Prestige ER18RNX and the T25CF001 Soft dome.
The 90dB 110mm Morel CAT 328 might have enough output too.
http://www.falconacoustics.co.uk/drive-units-1/morel-speakers-drive-units/morel-cat-328-110-tweeter.html
You'll need a notch at 4.8kHz on the woofer, but then the Thor has one similar : L2,C1,R1 on the Thor schematic anyway!
Alan Yates' Laboratory - VK2ZAY's Engineering Calculators - LCR Resonance
Looks doable to me. Doubtless a bit of fine tuning needed.
I looked at all the 18 series SEAS woofers in this context. Of course they all fit.
SEAS PRESTIGE WOOFERS
The Paper CA18RLY was too efficient to easily match to a tweeter. The Poly U18RNX/P was nice but too different on bass parameters. Both were electrically rather different too. The Prestige metal cones were too difficult on breakup for this simple network. The CA18RNX had a midrange peak that would need attention.
All that needs doing here to the crossover is to increase R1 to 1 ohm to reduce the notch initially, because the paper woofer has less cone breakup. It's actually set at 4.6kHz, but that looks near enough. Usual SEAS simple network. Go to Troels Gravesen or Zaph Audio if you want fussier.
Uploaded with ImageShack.us
Mark K has a SEAS non-D'Appolito speaker that uses the ER18RNX with an "unusual" tweeter crossover. He deals with the bass notch very well:
The Seas ER18DXT ported two way
SEAS PRESTIGE WOOFERS
The Paper CA18RLY was too efficient to easily match to a tweeter. The Poly U18RNX/P was nice but too different on bass parameters. Both were electrically rather different too. The Prestige metal cones were too difficult on breakup for this simple network. The CA18RNX had a midrange peak that would need attention.
All that needs doing here to the crossover is to increase R1 to 1 ohm to reduce the notch initially, because the paper woofer has less cone breakup. It's actually set at 4.6kHz, but that looks near enough. Usual SEAS simple network. Go to Troels Gravesen or Zaph Audio if you want fussier.
An externally hosted image should be here but it was not working when we last tested it.
Uploaded with ImageShack.us
Mark K has a SEAS non-D'Appolito speaker that uses the ER18RNX with an "unusual" tweeter crossover. He deals with the bass notch very well:
The Seas ER18DXT ported two way
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Hi,
The Thor cabinet as it turns out it is not very well designed for the drivers it is
intended to use. Search and you will find expansive details of its design faults.
Reverse engineering indicates their best use is a 6.5"/1" MTM with a bass/mid
driver with parameters more suited to the line, offhand I can't tell you what
they might be without a deep investigation I'm not prepared to do.
Though I'd surmise a high value MTM with "mid level" drivers is likely best.
What you want is suitably different bass parameters.
rgds, sreten.
I don't have the MJK worksheets, what is needed here.
The Thor cabinet as it turns out it is not very well designed for the drivers it is
intended to use. Search and you will find expansive details of its design faults.
Reverse engineering indicates their best use is a 6.5"/1" MTM with a bass/mid
driver with parameters more suited to the line, offhand I can't tell you what
they might be without a deep investigation I'm not prepared to do.
Though I'd surmise a high value MTM with "mid level" drivers is likely best.
What you want is suitably different bass parameters.
rgds, sreten.
I don't have the MJK worksheets, what is needed here.
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Ooh, this is interesting. The original Thor designed by Joseph D'Appolito used the W18EX001 with a Qts around 0.26 according to Joe D'Ap's original design article.
http://www.seas.no/images/stories/diykits/thor/audioXpress_Thor_Review.pdf
This could explain a lot! That's a tighter control on the bass, isn't it?
http://www.seas.no/images/stories/diykits/thor/audioXpress_Thor_Review.pdf
This could explain a lot! That's a tighter control on the bass, isn't it?
OMG, a 110 pages of typical diyaudio waffle!
http://www.diyaudio.com/forums/multi-way/64799-clarity-seas-thor-kit.html
Seems obvious to me (on the merest quick glance) that these people are a bunch of Moaning Minnies.
I think we've fixed it in a mere page, eh, Sreten.
Because it's gonna be around 91dB SPL when twinned even with bafflestep rolling it off. Remember that doubling drivers adds 6dB.
H1217-08 CA18RLY
Compare with the original suggested driver which is 4dB quieter:
E0018-08S W18E001
I think you'd struggle to get the tweeter loud enough.
An externally hosted image should be here but it was not working when we last tested it.
Only 2 ohms to play with there.
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Well, God help us if this little thread turns into a http://www.diyaudio.com/forums/multi-way/64799-clarity-seas-thor-kit.html 110 page epic!
I've gotta admit I'm pretty baffled how the original design's W18EX001 got replaced by the less reflex friendly W18E001 . But we don't care in this case!
Seems to me that this is all pretty straightforward. The cabinet is just your regular folded transmission line something like this around 50-60L. Add some stuffing and damping to taste.
The Etude-TL is a design remarkably close to the Thor. It uses a couple of Polycone Vifa P17WJ-00-08 Woofers, which are almost identical on bass parameters to the Paper SEAS ER18RNX except for the change of cone material. Vas about 35L, Qts around 0.34, Fs around 35Hz. Metal Vifa D25 tweeter if that's your cup of tea. The Etude is a 2.5 design rather than a D'Appolito, but hey. I can actually see no significant difference in the two cabinets.
Seems to me this Thor cabinet is going to be OK. The Etude TL designer (Paul Spenser) claims no great grumbling bass. It's about what you'd expect from a 50-60L design. But you'd want a biggish room to avoid boom IMO.
Below the Thor and the Etude boxes.
I've gotta admit I'm pretty baffled how the original design's W18EX001 got replaced by the less reflex friendly W18E001 . But we don't care in this case!
Seems to me that this is all pretty straightforward. The cabinet is just your regular folded transmission line something like this around 50-60L. Add some stuffing and damping to taste.
An externally hosted image should be here but it was not working when we last tested it.
The Etude-TL is a design remarkably close to the Thor. It uses a couple of Polycone Vifa P17WJ-00-08 Woofers, which are almost identical on bass parameters to the Paper SEAS ER18RNX except for the change of cone material. Vas about 35L, Qts around 0.34, Fs around 35Hz. Metal Vifa D25 tweeter if that's your cup of tea. The Etude is a 2.5 design rather than a D'Appolito, but hey. I can actually see no significant difference in the two cabinets.
Seems to me this Thor cabinet is going to be OK. The Etude TL designer (Paul Spenser) claims no great grumbling bass. It's about what you'd expect from a 50-60L design. But you'd want a biggish room to avoid boom IMO.
Below the Thor and the Etude boxes.
Attachments
I believe the enclosure in question is one of the alternates and not the regular THot, so you volume estimates will be off.
dave
Hi,
Getting back to the original post a very good value MTM is :
(I think you'd be hard pushed to do a lot better up to $500).
My RS180 MTM Design
Excellent minimalist crossover design for such drivers, nice low x/o point
which is whats needed for a MTM, very much similar to the Thor design.
Except of course it costs bucket loads less and is far better value.
Suggest using a wide bar on the front of the speaker to tilt the
tweeter to ear height and aid the overall speaker stability.
I suspect the higher Fs / lower Vas drivers will better suit the Thor cabinets.
rgds, sreten.
I'd suggest a 47uF NPE and a 3.3uF Poly for the tweeter 50uF.
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Interesting design by Jeff Bagby there, sreten. He is a top man. Enjoyed reading that. Interesting remarks about the necessary midrange dip on MTMs. Lynn Olson ran into that one on the Ariel. I also like his notion that speaker crossovers virtually design themselves.
Just to tie up a loose end, Planet10, I used the published SEAS Thor data:
Thor
You need a good amplifier for these 4 ohm babies, don't you?
Just to tie up a loose end, Planet10, I used the published SEAS Thor data:
Thor
You need a good amplifier for these 4 ohm babies, don't you?
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