2-way with 10" woofer

[crazyhub]

Hello all,

I'm planing to build a 2-way using the Seas CA26RFX:
http://www.seas.no/Prestige%20Basser...X-H1305-08.pdf
and, at first sight, the Seas 27TDFC:
http://www.seas.no/seas_line/tweeters/H1189.pdf
I know I'll have some difficulties to get a right mid-range; so I thought on placing the woofer 45° backward leaned on the top of the enclosure in the way to "naturally" smooth the CA26 bumps(at least at the listening point) and also because of the loading principle I will use; the filter will be a high slope acoustically at 1500hz, the lower I can go with this tweeter. Tweeter will be placed behind the woofer.

So guys, any suggestions about this project? Do you feel it is possible to get a good mid-range or will I have to choose another tweeter for a lower X-over point?

Thanks,

[DarkOne]

Hi Crazyhub,

CA26RFX has recomended frequency range 30 - 1000Hz and I think that people in Seas know what they write to datasheet. Maybe FR cuve of the driver goes to 3kHz, but there might be another problem above 1kHz, which you can not overcome. I'm not trying to say that it will be wrong driver for your purpose, but there might be some problem.

If you place the woofer to 45 degrees baffle, you might get smooth FR curve, but note that peaks in on axis FR will be reflected by your room right to your ears.

[crazyhub]

DarkOne,
Thank you for your response.

I know there will be problems above approximately 1khz, certainly distortions issues (break-up of this 26cm probably does occur at 800-1000hz); leaning the woofer will not lower the bumps of-axis but help a bit on-axis regarding that my room is relatively high; but I agree this will not be enough, so I want to know if it does exist a tweeter which can support to go down to 1khz; somebody advised me to use the BR Neo8; I will make a new thread about this tweeter to know a little more about.

[filgor]

Any tweeter that can be called a hi-fi tweeter really shouldnt be crossed bellow 2kHz and even then only for low system power maybe 50watts per channel or even less. The tweeter will be mechanically and electrically stressed.

A steep crossover slope will really only mess up the crossover region
The truth is both drivers would be at their worst right in the frequency range where your hearing is most sensetive to sound quality

If you really want 10 inch drivers making the bass go for a 3 way system or a sub and satellites system.

If you seriously want to build a simple two way system you should consider the tried and true MTM set up.. two 6-1/2 inch drivers above and bellow the tweeter in each channel

Two 6.5 inch drivers can kick out almost as much bass as one 10 inch.
You can cross them higher so that the tweeter is only being driven with frequencies it can handle well.

Please consider

[crazyhub]

Yes Filgor,

I agree with your thoughts; With conventional tweeters, the main problem is with mechanical moving parts displacements at such low fr. However I don't want to use smaller woofer, even MTM. If I don't find the tweeter I'm looking for, I will go to a 8" woofer. BR Neo8 seams to be relatively hard to smooth from 1 to 20khz.
Another solution could be horn loading a conventional tweeter but this would need a large baffle.
I'm middle of the pond.
Thank you for your opinion.

[keyser]

why do you persist in building a 2-way speaker? A big woofer has its limitations when it comes to reproducing the mid-band. As filgor said; a 3-way or a 2-way with a subwoofer should be the way to go.

[cotdt]

3" midtweeters like vifa trius and hi-vi 3" does the mids and treble, and does them very well, better than many dedicated mids and tweeters. You can use a crossover point of 400-500hz with a 12" subwoofer. Unless you are planning to blast them super loud at parties, they should get decently loud.

[Jezz-the-Fezz]

Hi Folks,

Don't know whether this might be an alternative:

http://www.ejjordan.co.uk/drivers/jxr6.html

Cheers - Fez

[Nemophyle]

A possibility would be to use a waveguide. It would allow you to cross a low Fs tweeter like the seas at around 1,2 khz i think. You should wait , zaph is actually testing the two PE waveguides, and i presume that he will test them with a tweeter very similar to yours

Any tweeter that can be called a hi-fi tweeter really shouldnt be crossed bellow 2kHz and even then only for low system power maybe 50watts per channel or even less. The tweeter will be mechanically and electrically stressed.

zaph used the 27tdfc with a linkwitz riley 4th order at 1.7khz with great success. But the only real way to go if you want to cross really lower is waveguiding this tweeter

[noah katz]

I agree about the waveguide.

Read about the theory here

http://www.4sptech.com/version2/index.html