Newbie troubles with Seas W18

[kravi4ka]

Hi all,
Being the worst type of newbie (lots of enthusiasm,good experience with expensive commerical speakers,no measuring equipment and software,studied the forums for almost 6 months now ) I am in a frustrating situation: I have a pair of Seas W18E001s and I am dreaming of a very high quality 2-way system.Since the consensus is that this is agreat driver but needs to stay down to 1.2-1.4 Khz I am really worried becuase I have no XO designing abilities and it looks like the W18 really is tough.So I sent a few e-mails to respected people in DIY and was advised to try and adapt the W18 to the Modula MT crossover (exactly the size of box I like). This is way beyond what I understand (read conventional LR stuff,not profound in any way) so I am looking for help in my quest for a good speaker. Since I do not live in the USA I cannot use the Rs28s and I am limited to the Seas line (TDFC or even Millenium) and would really appreciate any advice-reading for Cauer-elliptic stuff,free software, opinion ("forget it" works great too or even if someone has already done a design and is willing to share it with me too. Please excuse me for not contributing anything and thanks in advance. ops:

[TacoD]

I have a Seas Millenium/ Seas W18EX001 x-over (cauer @ 1300Hz and part of a 3-way), pm me if you're interested then I can try to make do a 2-way from it (with some bafflestep).

But another approach is to buy the plans from northcreek, they have a very high-end design with the W18E001 and their own tweeter.

[Brian Bunge]

You could also get Madisound to design you a crossover with the Seas tweeter of your choice.

[Jonasz]

Here you can buy the RS28A in Europe. http://www.boxen-baustelle.de/
Not the same incredible price as in the US but still worth every penny!

[JonMarsh]

I've suggested in PM previously to adapt the Modula MT design. I can make a version specific to the 27TDFC, but I don't have data files for the W18- there is enough similarity in repsonse and impedance curves in the passband that I think it would work fairly well.

[TacoD]

I've also a MT design for the Dayton/ Seas Noferro 550 (softdome version of 27TDFC) or Scanspeak 9800. I'll dig up the x-over.

Seas version:


it's not 100% 8th order but close enough of Jon's cauer.

[kravi4ka]

Thanks everybody!I have been reading the Modula MT thread with great interest when I got the W18E 001s as a present and this made my choice. I got lost trying to come up with an XO of my own and the Northcreek is out of my reach for now,though I am aiming at a very high quality system since most of the equipment I brought with me from USA is fairly good,not as good as the Ayre but still very good. So I was afraid that just dropping in the W18 in the modula is not optimal and after reading all this stuff about the 1.2-1.4 Khz being best decided to ask for help here. I can stretch my budget to the Millenium,the TDFC is an immediate option and since I don't have measuring equipment I am a little afraid of the Rs28 too (probably this inconsistency is not as bad but as I said newbies read too much ) and man,is that price plus shipping to me close to the Millenium!! (thanks for the advice,Jonasz,appreciated).
So if you tell me where to look for these data sheets for the W18 I might try to do something and if you have time to adapt the Modula for the Seas driver it will really make me happy (and many other people probably too).I know that you can't take care of every guy with a pair of drivers but I was hoping for a response.I can wait as long as it takes and if there is a chance to have a Cauer-elliptic for the W18 I will do everything to help. Thanks again,I have been tempted to post because you guys are so tolerant and great.

[JonMarsh]

It should be done by sometime this weekend... thank heavens for LspCAD.

[Dennis H]

Seas Data

I have the data files that Bjorn Idland of Seas provided a year or so ago. It's a 300K zip that includes all the tweeters and 7" woofers available then. There's a readme that describes the measurement conditions and a jpeg of the test box. Basically, anechoic chamber, no gating, 8" wide test box, mic on the tweeter axis at 1m. I forget where I got it (maybe Zaph's site?) and can't find it online so I posted it to my webspace temporarily. Grab it quick if you want it.

http://www.crestviewcable.com/~catapult/Seasdata.zip

[JonMarsh]

Grabbed! Thanks, Dennis. That should be close enough to work with, with just a little adjustment.

[kravi4ka]

Hi,
I am actually moving forward with my "project" as I found a good source of high grade Birch Plywood and will order one sheet to start working on the enclosure (either the box for the Modula MT or something like the Northcreek Pegasus box). As it is kind of difficult for me to buy Whispermat or Sonnic barrier from where I live I will really appreciate it if someone can help with ideas how I can improve the regular egg crate foam that is available here - may be some bitumen pads under it or neoprene pads glued to the walls? Or is there a supplier of Black Hole 5 in Europe? I think Jonasz gave me a site with a lot of stuff but I don't speak German,may be there are other sites or what should I look for in German? Thanks again

[kravi4ka]

About bracing

Hi again
I think Jon Marsh is kind of busy lately and my hopes for W18/27TDFC are still in the air but I have been cutting and routing a lot and got to the point I need some help again. I am building a box that is something between Northcreek Pegasus and Ellis 1801. I decided to use a Precision Sound port and I would like to place it behind the tweeter but then the horizontal arm of the ladder brace I plan to use will be behind the woofer magnet.There are about 15 cm ( or about 6 inches) between the magnet and the brace which is 25 mm(1 inch) and is rounded and I was wondering whether there will be any back wave interference with the brace and if it will affect the sound.Please advise. And there is something else- since the Precision Sound port is big on both ends the port will not be right behind the tweeter but lower,closer to the woofer level-not much but I am kind of paranoid and wanted to check that too.Thanks in advance.

[johngalt47]

Results?

Did you ever finish this speaker? What did you use for the crossover?