Clarity on Seas Thor Kit

I've had the parts for the 3rd order Thor XO (the one which appeared on Madisound's webforum and which was also posted here). Finally wired it together yesterday. This is just the electrical response into purely resistive loads for the Madisound XO from the original AX article, and the modified XO:

An externally hosted image should be here but it was not working when we last tested it.
 
Well, I've had my Odins with Jimangie's modified XO up and running for a couple months now and have a few hundred hours on them and would like to share my impressions on my first DIY.

The build was very straight forward and not very complicated using SEAS standard Odin box design. I was a little hesitant on the veneering, but with the right tools it made it a snap.

When I first hooked them up to my test system, a vintage Yamaha R-1000 I immediately noticed how detailed the highs and voices sounded, but they were very constrained and didn't present a very wide field of sound. The bass was also lacking and figured I'd need a subwoofer, but not that big of a deal. I knew that they needed some serious hours logged on them to be fully broken in, but to be honest I was a little discouraged for as much money and time I had invested.

Fast forward to the present and they don't even sound like the same speakers anymore. The imaging of the vocals in well recorded music is truly outstanding. Alison Krauss in "Lonely Runs Both Ways" is incredible. "Russia on Ice" by Porcupine Tree is a song I love to use to put a pair of speakers thru its paces due to its wide range of sound. From a single cymbal that sounded crystal clear with just the right amount of sustain and fade to a bottoming out string of notes from the keyboards. The sound is fast and tight and not fatiguing in any way. I work from home and they are playing constantly throughout the day and sometimes at more than moderate volumes.

I no longer have the urge to get a sub woofer as the bass in my office environment with the Odins now hooked up to a Pioneer SX-1080 is more than adequate and actually quite surprising the amount of bass that these 7" woofers put out. After break in the lower end really came alive. I've never had experience with breaking in speakers, but these really benefited from being played and they just continue to get better.

I'm sold on SEAS drivers and I'm already looking for my next project with them, preferably something with a 10" driver to be a truly full range speaker.

Thanks for everyone's help and I couldn't recommend Madisound any more for anyone looking to build their own speakers. There were awesome! I live in Madison and stopped over there a couple of times and they were always quick to help me out with my questions and show me around.

Here's a link to some pics

Odin - DIY Speakers pictures by turbox2 - Photobucket
 
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I've had the parts for the 3rd order Thor XO (the one which appeared on Madisound's webforum and which was also posted here). Finally wired it together yesterday. This is just the electrical response into purely resistive loads for the Madisound XO from the original AX article, and the modified XO:

Looked on the Mad-webforum and couldn't locate a XO. Do you refer to the one in post #998 ?
 
The weather stinks here, and I am not about to trudge these things outside to measure the XO's so I just set it up for a rough and dirty nearfield approximation of the two XO's -- the first is the design as it appeared in AX -- a first order LPF and 3rd order HPF and the correction made for the magnesium:

An externally hosted image should be here but it was not working when we last tested it.


and this is the result for the XO as it appeared here and on Madisound's forum --

An externally hosted image should be here but it was not working when we last tested it.
 
Member
Joined 2004
Paid Member
The weather stinks here, and I am not about to trudge these things outside to measure the XO's so I just set it up for a rough and dirty nearfield approximation of the two XO's -- the first is the design as it appeared in AX -- a first order LPF and 3rd order HPF and the correction made for the magnesium:

An externally hosted image should be here but it was not working when we last tested it.


and this is the result for the XO as it appeared here and on Madisound's forum --

An externally hosted image should be here but it was not working when we last tested it.
:confused:
I'm not seeing A graphic here, should there be one?
:(
Also, never got a response to post#1007.
 
:confused:
I'm not seeing A graphic here, should there be one?
:(
Also, never got a response to post#1007.

The new XO was referenced on Madisound's forum to this thread at HTGuide forum -- it's on the 5th page:
HTGuide Forum - seas thor crossover redesign help
http://www.htguide.com/forum/attachment.php4?attachmentid=10703

D'Appolito designed the original LPF section to deal with the rising response of the paired woofers at around 400Hz, and a resonance at 4.5kHz with a 10dB peak. Perhaps Dave can opine, but the suggestion was made that the peak was dealt with "inadequately". I don't see this to be the case with the original XO's.

The 8 ohm resistor in the impedance matching network of the HP on the new design is too low a value.
 
The end of the bevels will determine the effective width. Being much wider any BSC comp built into the XO will be thrown way off (ie in theory you should get a big hump below about 500 Hz)

dave

The original XO from the AX article just used 1mH as an LPF.

Here's a screen dump of the 4.5kHz corrector's effect from the AX article -- it is "inadequate" as suggested:

An externally hosted image should be here but it was not working when we last tested it.
 
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I worked backwards with a BSC Calculator, determined that the effective front baffle width was about 11 inches -- here's a screenshot with (lower green trace) and without the correction (1.5mH in parallel with 3.7R):

An externally hosted image should be here but it was not working when we last tested it.


Edit: This is the XO from the AX Article
 
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A bit of a late question - I hope that this thread is not dead!

I was a bit of an early adopter of the Odin and built the early design with the W17-E002 drivers and Millenium Tweeter. I went with a xo design that was faxed to me by Seas USA, upon an advisory from Madisound about concerns with the original design. I also upgraded to Alphacore Inductors and Sonicraft caps..

I am keen to try Jim's design, but of course I have the question about compatibility with the W17 drivers, which have slightly different T/S parameters...

Does anyone have any advice on this?

cheers

Simon