6.5 vs 8 vs 10 woofer

@Mozartfan
I was with you in the wideband hi-eff thread, but this 10" theory makes little sense. @auxinput gave you very important information. he's right. even a 15" hi-eff are limited in low bass due to the hi-eff design choice in building a hi-eff woofer. so a 95db 15" woofer need a BIG cab to make low bass: like 200L or more.

- no 10" wideband will reach 20khz smoothly. the rising response will be impossible to deal without compensations circuit to smooth that rising response

- a 10 inch wideband still need a light cone and relatively weak magnet= compromising low bass, and Ive heard a couple like the famous 10" vintage philips. they just dont do low bass

if you want a wideband and bass, look at FAST designs (fullrange-assisted-system-desing) at diyaudio. whole following there.

If you want wideband sound and real bass, you need subs. If you dont listen loud, get a 5, 6 " voxativ in a small sealed enclosure and try to make the wideband roll off naturally around 100hz, then integrate dual REL subs

hope this helps

PS: if you want hi-eff and real bass, go the classic way: hi-eff 15" woofer with a 6.5" hi eff mid and hi-eff 1.5" tweeter (seas t35 are 96 db) and go for a 1st order xo.
I’m building right now such a speaker with a Eminence omega pro 15", audax 170mo mid and hivi planar tweeter, 1st order series xo in a 200L cab. This system will be about 96 db efficient.

My wife say after having 6” and the 8” she like my 10” best of all. 

8" is a good. Mid-bass is a compromise so to minimize Doppler on the low end I needed 6 on each side, sealed box. Kind of blew the budget.

Then XO @ 58 Hz to 15" corner horns which is all right to 25 Hz for most music.

Then XO to the sub-sub 14’ T-line 4x15". Three of those. Flat to 4Hz. Could not measure dB. Had to estimate via Richter. Also doubles as a hair dryer. 

Couldn’t find the Hartley at the time of the build.

Full range drivers are always a complete compromise anyways where you sacrifice some aspect of the sound/characteristics to get what you want. It is actually incredibly difficult to engineer and manufacture a full range driver that really works well throughout the entire frequency range.


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Yeah I'm now firguring this  weakness of a  FR 8. Its super in the midrange,
But by itself, it does not have enough width and depth = soundstage was a  bit ~flat~~
so i pondered what can i do in the meantime while i save up some audio buget cash for the Vox 8...hummm, well lets see, I have the Thors collecting dust,,,thinking kind of liked something about the thors,,but not sure what the issue was that made me slam the Thors,,,so i figured since i have a  nice rich mids/some upper highs,,in the 8 FR,,thought i might as well disconnect the Millenium tweet ad run the other speaker cable to the Thors. 
BINGO, Soundstage returned very nicely. 
Just this moning wanted to ck what the dual W18's sounded all  alone on one channel and the other with the FR8,,,,sure enough the Excel W18 magnesius 87 db 6.5's were a  smash hit.
The lowes only go to 40hz. But what is so unique about this EXCEL W18 is the fq's between say 100-2000.
Here is where this driver really shines.
This super critcal range is voiced with no stress, no faatigue, just pure music.
I could not live without this W18 Excel. It simply must be in my system/ 
Now i note the Vox 8 is really FULL range,  that driver rocks, I know after countless YT vid listening sessions. 
How will the Vox8 intergrate with the dual W18's, Remains to be seen/= heard.

If the Vox seems a bit flat, I have no choice but to interfrate the dual W18's.
Will not mploya  compression horn tweet  either Davidlouis or 18 Sound. 
The Vox 8 has stunning highs. 
So taht saves me $400/DavidLouis or $650/18 Sound. 

Its good i did not dump the Thors for asking $800,  that would have been a gigantic mistake.
The new xovers, the cabinets, the dual W18's for $800?? I must  have lost my mind.
, , The tweeters will be dumped on Ebay, brand new for some change/ going auction style.
As per Richard Gray, **I hate dome tweets*. 
The dual W18's, really voice gorgeous in the upper bass, low mids. 
 Those W18's I could not live w/o.
The LII fast 8 FR is worth only what you pay for it.
The bass is a  bit thin and  mids  a bit too warm = muddy.  All my system is geared to be clear/ clean,  that is i attempt to eliminate all *warm*. 

 The LII Fast 8  will  have to do til I get the Vox8. 

hi-eff 1.5" tweeter (seas t35 are 96 db)


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When i order a new pair of Millenium, instead the far superior dome tweet is this Exotic T35 you mentioned.
Its 94db eff.
No doubt would have blown away the Millenium and thus , may have been completely satisfied and not looked any further into going FR.
But as it is, FR is on my agenda.
The T35's voice coil is only 1.3 inch.
Thats just too small to voice large full orchestra.
Just can not  deliver the wide sound stage that i am looking for.
But indeed, the T35 Exotic might just be the exception to Richard's opinion  about the weakness of all dome tweets. 
But then the T35 is going up against the new compression horn tweets with 100++ sens. 
I'm done with midrange tweets (1500-20k) 
The new FR voices midrange with wider/deeper sound stage. A fullness  with fidelity, purity. Accuracy.
Dome tweets squeeze the complex passages thougha  minisclue 1-1.5 inch exit chamber.  = Nice try, no cigar.