Bookshelf 3-way

[vozemer]

Hello all.
I'm thinking about design compact 3-way speaker with active filters. My goal is to achieve good bass perfomance and neutral detailed sound.
For bass section wanna use Usher 8836A 7" midbass, crossed with Dayton RS52AN-8 2" dome around 800-1000 Hz. On top - Dayton RS52F-4 or RS28A-4 crossed 3-3.5 kHz.
It will be closed box with Linkwitz transform circut. Calculations shows in 12 liter box (0.4 cu.f) with F3=50 Hz it can achieve 97 dB without violating Xmax. Normally I'm not listening loud so...
What do you think? Any design built yet?
Thanks.

[DougL]

My brother used the mid-range as a replacement for the dome in his phantoms, along with a foster planer tweeter and 2 4.5" arogel woofers in a PR box.
very satisfying.
Remember, its all about compromise.
I might have looked for a 8" or 10"woofer, since the Mid-range goes to 800 Hz, but it would be a bigger box ...

Sounds like a plan.

Doug

[vozemer]

Browsed Internet I'm inclined to use RS28F-4.

BTW how to edit my first post?

[boris81]

Editing only works for the first few minutes and then it gets disabled.

Your design idea will probably work but I don't understand the need for a 3-way. There are a few tweeters that can be crossed over low enough to match a 7" woofer.

If I was in your situation I would probably use the Seas DXT tweeter and try to match it's dispersion characteristics to a 7" woofer as it was done by Mark K in his ER18DXT design.

[adason]

stick to dome mid, you will not regret it

[MisterTwister]

with these drivers I'd choose ~500hz and ~1.5khz crossover points.
about your crossover points - 800-1000hz - that's where Usher 8836A cone starts to breakup(audible). With 3-3.5khz RS52F's humongous 18khz resonance still may get excited(perceived as clear crisp sound, detail). And RS28F will be pretty much idle, not using even third of it's potential.
It's just my opinion.

[vozemer]

Originally Posted by boris81

Your design idea will probably work but I don't understand the need for a 3-way. There are a few tweeters that can be crossed over low enough to match a 7" woofer.

My idea is to use each driver in preferred range. For woofer it will be up to "piston" frequency. And also I really want to taste dome mid. That's why it's 3-way.

Originally Posted by MisterTwister

with these drivers I'd choose ~500hz and ~1.5khz crossover points.
about your crossover points - 800-1000hz - that's where Usher 8836A cone starts to breakup(audible). With 3-3.5khz RS52F's humongous 18khz resonance still may get excited(perceived as clear crisp sound, detail). And RS28F will be pretty much idle, not using even third of it's potential.
It's just my opinion.

Did you work with this woofer? Normally it should break-up close to 2 kHz in my opinion.
For mid possible to use notch to block unwanted resonances.
I choose RS28F because it's low distortion, mid priced and has mesh grille (child protection )

[sreten]

http://www.humblehomemadehifi.com/do...20Box_copy.pdf

Hi, the above might be worth a look, with a more sensible box design, rgds, sreten.

[MisterTwister]

I have not used this woofer, I just looked at its impedance curve. First wiggle is at 800hz, that's where cone starts to breakup. I try not to use drivers above their breakup points.

[vozemer]

Originally Posted by MisterTwister

I have not used this woofer, I just looked at its impedance curve. First wiggle is at 800hz, that's where cone starts to breakup. I try not to use drivers above their breakup points.

I looked at few 6.5-7" drivers and most of them has break-up below 1 kHz.
Maybe you can recomend the 7" driver with Fs below 35 Hz and small THD priced less $100/each?
Thanks.