Ok so I have some now out of production drivers I was going to build a two-way out of...
Woofer
Tweeter
but when I began modeling in winisd I discovered the woofer power handling below 100hz was very low. So I am toying with the idea of using it as a midrange doing a 3-way inspired by one of my all time favorite designs - the Kef Reference 105.2 , with each driver having its own separate enclosure stacked on each other.
I measured the t/s parameters for the dynavox and got different values that the ones posted online. Any way my modeling has me estimating a 0.25ft3 sealed enclosure for the mid. I am considering using the 12" Dayton designer series paper woofer with a 1.9ft3 ported cabinet tuned to 30hz for an f3 of roughly 38hz (that may change if the dayton measures differently on my DATS).
I have a question regarding woofer and midrange sensitivity - I have read for 3-ways you want your woofer to be 3db more sensitive than your midrange. Is that still true with separate enclosures? The Dayton woofer which has a 91db rating, and my mid is roughly 88 so that would work perfectly if that still applies.
Thanks!
Woofer
Tweeter
but when I began modeling in winisd I discovered the woofer power handling below 100hz was very low. So I am toying with the idea of using it as a midrange doing a 3-way inspired by one of my all time favorite designs - the Kef Reference 105.2 , with each driver having its own separate enclosure stacked on each other.
I measured the t/s parameters for the dynavox and got different values that the ones posted online. Any way my modeling has me estimating a 0.25ft3 sealed enclosure for the mid. I am considering using the 12" Dayton designer series paper woofer with a 1.9ft3 ported cabinet tuned to 30hz for an f3 of roughly 38hz (that may change if the dayton measures differently on my DATS).
I have a question regarding woofer and midrange sensitivity - I have read for 3-ways you want your woofer to be 3db more sensitive than your midrange. Is that still true with separate enclosures? The Dayton woofer which has a 91db rating, and my mid is roughly 88 so that would work perfectly if that still applies.
Thanks!
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Of course. I was just making sure I didn't need to find matching sensitivities, or have a more sensitive mid since they aren't sharing the same baffle. If a woofer with 3db positive difference sounds doable I will probably move forward with this project and update my progress in this thread. I know I will need y'alls help again 🙂
I've never had success measuring my own T/S parameters. I don't know why, they always are different from manufacturer specs.
In the past, I've always gone with the manufacturer's specs. It's always produced good results. When you modeled very low power handling for the woofer: were you using your own parameters, or the published parameters?
If I were in your position, I would model the Dynavox in a sealed and in a ported enclosure using the manufacturer's specs and pick one. A Qts of 0.52 suggests it will work well in either type. See if you can find a configuration which will give you better power handling, and build that speaker. I would not be discouraged by the woofer's lower sensitivity, just put a resistor in series with the tweeter.
If you like it: GREAT! If not: then buy your 12" woofer.
As well they should due to manufacturing tolerances. I was able to get a very enlightening tour of Altec's plant in '68 where among other things I was interested in their excellent quality control, but when told they only measured efficiency, left 'scratching my head' along with a binder full of tech notes and a subscription to it.
One concerned T/S theory where I found essentially this except using Vas in ft^3, which allows considerable freedom and still meet spec and why with my personal designs have only bothered to measure Fs using Altec's +/- 15%: n0 (efficiency)
As always though, YMMV, etc..