8"+1" two-way DIY speakers

[crazyhub]

Hi all,

I know of a lot 7" or smaller mid-woofers matted with 1" or smaller tweeters but very few using a bigger woofer...Do you know of?

Thanks!

[JRace]

Reference 3a uses an 8" (without any crossover) mated to a 1" tweet, and a supertweet. They do refer to it as a 2-way.
Reference 3A Loudspeakers

A two way design utilizing our own directly coupled (no crossover) hyper exponential 8" (20 cm.) woven carbon-fiber main driver, superb 1" (24mm.) soft textile dome tweeter and a gold coated fine ceramic super high frequency exciter.

Front baffle is tilted back at a critical angle and the drivers are positioned precisely for correct time alignment and sound wave propagation.

Cabinet panels are constructed with varying thicknesses of 1½" (39mm. to 1" (25 mm.) to drastically reduce resonances.

Highest quality components with very advance technologies are used for enhanced refinement (Bybee Quantum Purifiers, Mundorf silver capacitors, Murata super tweeters and AVM fluid, Van den Hul wires, etc…).

And they do make a stand-mount 2way:
http://reference3a.com/mmdecapo.htm

TWEETER
Custom designed and pair matched.
27 mm. textile dome,
Non-resonant rear chamber.
Un-damped, dual suspension.
Low resonant frequency, 600Hz,
Cut off frequency 300Hz.
High pass frequency, 6dB/octave

MAIN DRIVER
8 ¼" diameter, designed and build by Reference 3A.
Designed not to require cross-overs.
Very wide frequency response.
Hyper exponential shaped woven carbon cone.
Exclusive Vibra-Puck treated driver structure.
Precisely shaped phase plug.

[JRace]

oopps
you did ask for DIY...

[crazyhub]

Originally Posted by JRace

oopps
you did ask for DIY...

Yes but only because my real interest is about the used slopes and Fx on such 2-way...Otherwise thanks for your input

[takayama69]

Hi

If size, price of drivers and complexity of the XO don´t bother... check out the Classic at HumbleHomemadeHifi's. Here you can find a 28 liter 2-way with dayton RS 225 crossed at 1400 hz.

But one puzzling speaker is Krell Resolution 3. Seas magnesium 8 and the XT 25 krossed with a third order filter at some point > 2 KHz in a small box (baffle is 2" to subtract from volume.. )
Anyone made a clone or just a dissection of the XO ??[IMG]
[/IMG]

[JRace]

Originally Posted by crazyhub

Yes but only because my real interest is about the used slopes and Fx on such 2-way...Otherwise thanks for your input

Then I guess a 8" with no crossover mated to a tweet with a simple 6dB @ 300Hz isn't what your looking for!

[CharlieLaub]

It's possible to do a good 2-way with an 8" woofer. The limiting factor is that the off axis response of many 8" woofers starts to drop around 1.2k Hz or so. Of course this depends on the design and material of the cone, the profile/shape, etc. But there are good examples in the DIY world of how to pull this off, for instance Mark K's RS225/RS28A:
Dayton Reference RS225
I've developed a variety of active crossover boards and I have a few 8" drivers that are candidates for a 2-way, so I am hoping to explore this type of speaker a little more in the near future.

Of course you can go "larger" with the tweeter and cross over lower. There are a couple of small (e.g. 2") inverted dome full range drivers from Tang Band that could be crossed over about as low as you desire (e.g. 800 Hz) to create a 2-way. For instance the W2-800SL.

Once you go larger with the woofer, the off axis response starts to be a real problem, unless the woofer has a special design that provides smooth off axis response. For instance, the Seas A26RE4 stand out. But most 10" drivers will just not be suitable.

-Charlie

[RockLeeEV]

Once you get to even a 6.5" woofer I think it starts to get tough to mate to a 1" tweeter.

By the time you get to 8" woofers IMO you should really consider waveguides.

How about pairing the upcoming Exodus Anarchy 8" woofer with the upcoming Seos-10 Eliptical waveguide. I don`t really know what drivers work in that SEOS 10 but i`m sure you can find an excellent match to the Anarchy.

The Linkwitz Orion does pair the Seas W22 with the Seas millenium, with a low (1.4khz) 4th order crossover point.

[jerome69]

Originally Posted by JRace

Then I guess a 8" with no crossover mated to a tweet with a simple 6dB @ 300Hz isn't what your looking for!

No I don't think so, although we have this kind of specimen

A 8"+1" is a classical design, no problem to find many DIY projects
Vifa C20WH
Monacor SP200X +
TQWT-
High Efficiency Speakers
Rôle du RLC - Enceintes
etc.

But with bigger woofers, it is more tricky. You can mate a 1" with a 10" or a 12" @1.5kHz or 1.1kHz no problem. I made it but as explained it is not ideal.
With a waveguide it is better for the tweeter which is very stressed.
But I still think, a 1" should not work under 2kHz.

[crazyhub]

Thanks for the replies guys but I have to precise a few things; I have already the drivers at home and I'm waiting on the enclosures builded by a carpenter; the drivers are:
http://www.scan-speak.dk/datasheet/pdf/d3004-660000.pdf
8NMB420 - High Output MB Neodymium Driver
A previous thread didn't give a lot of replies...:
xo for scan speak 6600

So the only and real purpose of this present thread is to give me an idea of what Fx and slope does give an acceptable listening result in term of directivity issues by browesring what others did already do. I guess I know all the technical constraints (mech x-max/power behavior), what I don't know is where to place the bar...In short, should I go as low as 1.5k or even 1.2k (tricky!)...or 2k is really suffisant?