Thinking Extremis... opinions please

Howdy,

Well, we moved and the new place is a single family home and the basement is mine (muhwahahah) for our HT.

In our last place, i had B&W dm602's as fonts, which i replaced with sheilded Orbs b/c of my pc-monitor placements - so i got 4 orbs for my L/C/R channels. (you can see them before i mounted the L/R channels here: http://www.hakalugi.net/gallery/old-ht/halo)

In the previously smaller room, and with an adjoining neighbor, it was enough sound. But when i did push things, the 80hz - 150hz region was the laggard. (even in 'small speaker mode' on my pre/pro, which cuts below 100hz)

So... i'm thinking of using an extremis on each of L/C/R to help round out the sound. Here are my questions:

1) Adire is honest in their specs, so the 86db sens. i can believe (and can be calculated) - the Orbs are stated at 89dbs each... and i'll have 4 of them on each front channel (in a line arrays) in a series/parallel wiring arangement (which should add to the effective sensitivity of the array) Orbs-array = 8 ohm, Extremis = 8 ohms, i'd parallel those for a nice 4 ohm load... but i feel that if i used a passive x-over the mid-bass would be lagging still (but at least not compressed) - how did your DIY Extremis projects go with regard to level matching? (note: for now, it'd be easiest to be a passive system using my 200x3 amp for the L/C/R... if i need 2 midbasses for each front channel, i might have to look elsewhere, $600 in Extremises is too much for me.)

2) since i have Orbs (http://www.orbaudio.com/index.asp?Pa...n=Custom&ID=25) and not just tweeers, i'm interested in crossing over not at the usual 2.5khz but lower, so the Orbs can sing. what lower x-over points have you used with success with the Extremis

3) my subs: i'm shooting for reference level :) (about 600-800 watts into each 12" driver each in their own Decware deathboxes, closer to the listening position than the L/C/Rs since i don't have the ability to delay the main channels to accomodate the processing delay of my BFD) i'd like to have the other speakers keep up, at least to a point. Amplification shouldn't be hard (the Acurus will go almost 400 x 3 into 4 ohms)... At $100 each, I don't want to buy 6 Extremises (2 for each L/C/R) but has anyone done one extremis for each channel? if so, how loud did it get as a 80 - 400hz driver?

4) If i want to test the T/S parameters of my orbs so that i can faithfully order/build a passive x-over, how would you do it? should i assemble the 'array' wired series/parallel then test it as one 'driver' ? (and what do you use for testing gear/software?)

Sorry to sound like a headbanger - but i liked the sound of the Orbs, but with my new subs, their one weakness will be exacerbated as i try to fill this larger HT room. (11 x 25, seating at 10', open stairwell going up in back left corner, 3 interior and 1 exterior door in HT room)

Thanks!

Hak
 
I'm happy with my Extremi, but if you are crossign at 400 Hz there are probably better choices. Anyway, here is the project JonMarsh and I did: http://htguide.com/forum/forumdisplay.php4?f=6

The efficiency is plenty good for me. They dont compress with power, and they take a lot of power. I ran them on 40 SS watts and plenty of BSC, no complaints.

As for the subs, if you have the room go with 15s or 18s instead of 12s.

Can't help with the orbs
 
Are you the same Hakalugi from SoundIllusions years past? If so, how are you doing? Haven't seen you around for a long time.

1) The Extremis is known for it's midbass (and lower) performance. That's one advantage of having all that throw. I think you will be very happy with a single unit within that window.

2) Most of the crossover points used by us when mating the Extremis to tweeters have been up at around 3kHz. You should have no problem with 2.5k or lower.

4) The crossovers are THE most important part of a speaker system. They are what give the speakers their "voice". To properly design a crossover you really need to measure the speakers in their intended enclosures. We use Praxis to do the measurements and crossover design work. It is pretty spendy to purchase all the test equipment and software though. If you like, we could probably design the crossovers for you if you ship us the speakers.


Steven Kephart
Adire Audio
 
hi Steven,

SoundIllusions - yes. Posted there for the first time in a while last month... people's post#s sure have sure climbed :)

Well, things have changed since this post, tho.... i've bartered my old Sunfire Junrio for a Pair of Martin Logan CLSs -

[IMGDEAD]http://www.audiorevolution.com/news/0702/16.martinlogan.shtml[/IMGDEAD]

so my L/R channels are now 'done' :) i just have to either come up with a center ch. that sounds similar, or find a new pre/pro that does phantom middle'ing.

i need to build a set of mini monitors with bass for our upstairs TV, so the extremis + tweeter would be nice.... do you guys have a 'kit' setup for that type of application?
 
The Extremis 6 looks quiet good on the spec but imo there are some drawbacks:
1) 10 ohm impedance. 10.0 is in fact measured Zmin except for freq near dc. For single driver applications a value of 7 ohms would be better for voltage sensitivity

2) High Mmd and moderate Bl results in very low efficiency
I measured Bl lower than spec

3) There is "rattle" or mechnical noise long before xmax is reached

4) Inverted nearly flat oversized dust cap.

I rather use a driver like Peerless 850439 (HDS)