First DIY project - Econowave standard w/ DSP bass boost?

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I've been an on and off lurker on these forums for a few years now, and have finally come to the point where I don't think I can resist the lure of putting something together.

I have very limited woodworking capability, so limited the search to things that have a flat-pack box available. One that almost immediately popped up was an Econowave standard, as seen here. Bonus points for being quite cheap, so if (when) something is broken or fried by my inexperience replacement isn't a huge deal. The only downside to this in my mind is the requirement for a sub. I really have no interest in buying or building a sub, so reading about Gainphile's Econowave-DSP was very interesting to me. He has boosted the low end with a miniDSP unit (as well as incorporated the rest of the crossover in the DSP).

However, I don't have the experience to dial-in a DSP crossover, especially after reading what seems like hundreds of threads here and other forums about the various difficulties of producing a decent constant directivity speaker.

This brings me to the million dollar question: is it possible/feasible to build the Econowave standard, analog crossover included, but include a miniDSP with a Linkwitz transform to boost the bass higher? I have modeled this in WinISD, and attached what I hope are the relevant charts: EQ transfer function, overall transfer function, amplifier power, and cone excursion. I chose a f(p)=35 Hz and Q(p)=0.707 for the Linkwitz Transform. This all seems a bit belt-and-suspenders, but as a step towards further playing around the miniDSP appears a good tool, and there's no huge investment made in the analog crossovers.

As far as I can tell this plan seems ok, with excursion less than 75% of Xmax at 20 Hz, amplifier power not crazy, and nothing affected anywhere near the crossover point, where it seems much of the directivity issues live. I'm definitely well out of my depth of understanding so appreciate there could be whole mountains of problems I'm not seeing!

Any input much appreciated -- I'm hovering over my parts-express cart just itching to hit that button...
 

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Some questions.

The bass is the Dayton Audio DC300-8 in a 1.65 cu feet knockdown cabinet?

From what i understood of the Econowave designs, 1/2 of the fun is having lots of headroom and dynamics, aren't you afraid the linkwitz transform will eat a big part of the max spl? I don't know the sim program you use. Could you try the amp power needed for x-max and take a look at your max spl? compared to the original design?
 
the s15 has some ridiculous EQ. 20db 10-20hz?
http://i.imgur.com/W7LjB.png

the 2x4 will distort like crazy from time to time, without padding down the input voltage by an equal amount. then you have another problem at the output, not enough voltage.
people seem to think they can do anything with a DSP without even thinking about what happens in practice.. digital clipping and woofer distortion that goes thru the roof at louder volumes.
 
well he could use the 2x4 or the nanoDIGI on a signal level (after or before the dac/source) as an EQ, with passive crossovers. then play with the settings in realtime to see what works out. or maybe build a floorstanding version to get a bit deeper bass,keeping bafflewidth the same.
diysoundgroup.com has complete kits, but they cost a bit more.
 
There isn't enough excursion for that transform (you're looking at 1W excursion). You could use the DSP for less aggressive bass EQ, although you'll still lose max. output pretty fast.

However, I'd like to point out that there is no need to use that passive xover. There are already .frd files for the in-cabinet measurements in the techtalk thread, which means that those can be loaded into REW, EQ'd to flat, crossed with LR2 or LR4 at 1.6k in miniDSP, EQs from REW loaded into miniDSP driver EQs, target EQ (including any bass boost) loaded to channel EQs in miniDSP, and then there's only driver delay left to fix, which can be done well enough with a test tone and smartphone measurements, maybe even by ear.

I know that's not exactly easy to read instructions and important details on how to do those things are left out, but I'm just trying to point out the option at the moment.
 
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