Seas L18RNX/P in an MTM configuration?

[GOWA]

Has anyone used the Seas L18RNX/P in an MTM configuration? I'm looking to build a nice set of mains for downstairs and I love these drivers.
Thanks.

[Dave Bullet]

Although not an MTM, Zaph designed (although never built and tested) a TMM with the Seas 27TBFCG tweeter and 2 L18 woofers here:

http://www.diyaudio.com/forums/showt...40#post1077540

Just checked - and Zaph's link to his site is broken. I do have the crossover so if Zaph doesn't mind I can post here for you.

I siulated a TMM (same thread as above here:

http://www.diyaudio.com/forums/showt...15#post1106315

The problem with the design I did is I believe the 0.5 woofer is playing too much into the midrange (full 1.0 woofer space) which will adversely affect the sound (ie. midrange will be "smeared" for want of a better word).

I'm currently working on a 3 way with an L26, L18 and 27TBFCG.

Let us know how you go / what decisions you make. I too like the look of the Seas L series drivers. The L26 also tested out well on Mark K's site

Hope the above helps,
Dave.

[kyselym]

L18 as midrange in 3way is not a good idea to me. I think L15 would do this job better.

[GOWA]

Can you elaborate?

[kyselym]

Can you elaborate?

me? elaborate what? why L15 will do it better or about MTM using L18? either I don't think my english is as good to be able to well explain why...

Do you know that L18 has to be crossed realy low? around 1.6-1.8Khz to achieve very good results?(as steep as possible) L15 will be fine with 2-2.25Khz. You will have problems to find suitable tweeter for a pair of L18 to handle such low crossover point at high power levels. There are more problems...and you will have to measure not only simulate.

Only thing I can do for you is, I wil give you construction plans, measurements and crossover design for speakers I'm going to build. It will use 27tbfcg tweeter L15 as midrange and pair of L22rn4xp in closed box. It will take around 1 year till it will be finished and there is a option that I will not suceed to cross it well and will have to use one L26 instead. But I don't think you want to wait so long. so my advice is to find some 3way design using theese seas L drivers and build it insted of designin own MTM with L18.

example:
http://www.rjbaudio.com/AlpheusMkII/alpheusmkii.html (try to ask RJB for older version taht uses L12)
or if you insist on MTM: http://www.hardwareanalysis.com/acti...tarticle/1815/

or build zaph's:
http://www.zaphaudio.com/audio-speaker12.html
and support them with two small subs with L26 or L22 with active crossover if the bass will not be enough.
or just build zaphs L18 design with one L18 and instead of using second L18 as 0.5 woofer use bigger like L22 with appropriate pasive crossover(not as good idea as you might think but you can go active later)

so many ideas...

[Mor den Siur]

or build zaph's:
http://www.zaphaudio.com/audio-speaker12.html
and support them with two small subs with L26 or L22 with active crossover if the bass will not be enough.
or just build zaphs L18 design with one L18 and instead of using second L18 as 0.5 woofer use bigger like L22 with appropriate pasive crossover(not as good idea as you might think but you can go active later)

so many ideas... [/B][/QUOTE]




Hello

Is there anybody who tried using Zaphs L18 design with L22 in 2,5 way passive crossover??
Like in:
http://www.highfidelity.pl/artykuly/0612/marcus.html

[GOWA]

John Krutke successfully created a two-way with the Seas L18RNXP so I don't quite understand why not an MTM.
http://www.zaphaudio.com/audio-speaker17.html

[Mor den Siur]

Yes I know.

But I hope someone has some information about such project.

[GOWA]

Look at this.

http://www.nuforce.com/Product-Speaker.htm

[Dave Bullet]

GOWA,

In the link I provided, Zaph explains why he wasn't happy with the TMM 2.5 way he designed. Here is the link directly to his post:

http://www.diyaudio.com/forums/showt...40#post1077540

Zaph tries to simplify his crossovers for cost and complexity reasons (unless the quality of the drivers justifies a more complex than usual crossover - ie. his ZD5 speaker). Either he wasn't happy with the complex crossover for a TMM 2.5 way based on the L18, or moved onto a more interesting project, who knows.

David.