compact satellite with 80Hz xover

[dougr]

Maybe heresy around here, but are there any good options for compact (in the neighborhood of 2L or less) full range drivers that would crossover low enough to eliminate sub localization in a 7.1 setup? Cost is a concern since it is 7.1... if not, I'm indifferent between 2-way solutions that reach down to 80Hz xover or full range satellites with L and R subs that reach to 150Hz xover... any thoughts/ideas are welcome.
Thanks!

[Richard Ellis]

The Fostex line of drivers is perfect for your application..The FE126E would fit the bill quite nicely.
Using the suggested "standard" enclosure would be a straightforward woodworking build & you wouldn't have to design up a crossover.
93 Db is a great number! www.madisound.com
______________________________________________Rick .....

[Henkjan]

how about these:
http://www.diyaudio.com/forums/showt...42#post1805742

[dougr]

Originally posted by Richard Ellis
The Fostex line of drivers is perfect for your application..The FE126E would fit the bill quite nicely.
Using the suggested "standard" enclosure would be a straightforward woodworking build & you wouldn't have to design up a crossover.
93 Db is a great number! www.madisound.com
______________________________________________Rick .....

The fostex standard BR enclosure is >10L (bigger than I was looking for), and a bit more expensive than I am looking for as well (although not out of the question if the rest of the qualities are on target).

Originally posted by Henkjan
how about these:
http://www.diyaudio.com/forums/showt...42#post1805742

Been following this, nice cabinets by the way! You used 4L cabinets, and have commented that it would work down to 2L at the expense of loss of bass... Have you tried this? How low could I cross this with a 2L enclosure? The price is decent at $50USD per pair.

zaph's design for the hivi b3s is ineteresting, but crosses too high for a single sub in HT (150Hz).

[Henkjan]

I have not tried the 2 liters, that is just based on the sim.

where to cross also depends on how your setup is. if you can independetly set the HP and LP than you could cross the 2 liter around 80hz, the sats already have their own HP, so set the sub LP around that at 18dB/octave and you have a good chance on success. if you have to use a 'single setpoint' x-over in yr 7.1 set, you would be safer using the 4 liter version and crossing over at ~100Hz, you'll get a much better integration that way.

the usual disclaimer: this is my experience, ymmv

[planet10]

2 litres & 80 Hz is a big challenge. mFonken (FE127e/4.5 litre) or CHR-70 (sealed >4 litre) would make the cutoff but not the size.

uFonken (FF85k) is 2 litre, but only hits 100 hz (and with somewhat limited loudness levels). A real stunner thou.

A box that small is really going need a 3"

dave

[qingcai]

any sub woofer work with the uFonken ?
and which is best cross requency?

thanks.

[chrisb]

Originally posted by qingcai
any sub woofer work with the uFonken ?

probably, much of the appeal of the sub-sat approach is the teeny-ness of the "sats" - it's always nice to use an equally compact woofer.

There may be any number of commercial products out there that would suit the application, but I've yet to hear one that couldn't be bettered by a DIY or kit , for a fraction of the price.

The CSS SDX7( or similar) can deliver great performance in boxes as small as less than 1 cut ft per driver - sometimes the biggest issue is making the box (just) big enough to fit the plate amp of choice. Of course if you can afford the space for outboard amps, that problem disappears.

and which is best cross frequency?

thanks.

aye, there's the rub -

What we ended up with as XO for the Tysen/uFonken was high enough ( 300Hz - ish) that stereo woofers ( can't really call them "subs") were mandatory, and was also beyond the range of built-in filters of any plate amp we could find. No big loss there, as the filters in most budget plate amps is definitely not their best feature.

With careful selection of drivers to allow for simple 1st order filters, calculating and building a passive speaker level XO at this range wouldn't be particularly difficult, but the parts could be very costly and large.

The most practical solution was line level XO (active or passive), and bi-amping. The number and value of parts required for a simple 2-way PLLXO are such that the cost of the enclosure / jacks and interconnects could easily be several times more.

[planet10]

Originally posted by qingcai
any sub woofer work with the uFonken ?
and which is best cross requency?

How low you cross will deteremine how loud you can play.

The very 1st uFonken we built also included a 1/2 ft^3 SDX7 sub with the Keiga 2.1 plateamp (satelite amps built-in). The Keiga has a maximum XO of 150 Hz, and this is a reasonable compromise. The sat amps in the Keiga were really dissapointing, but we found that each channel has a compressor board in it, that once removed makes the amps much better (still not great).

That lead to us building stereo 17 litre SDX7 boxes as stands, and that turned out so stunninly well that it lead to Tysen which turned that into a dedicated bi-amped 2-way with XO at 333 Hz.

At one point i popped in the uFonken in place of the Fonken on top of the push-push SDX7 woofers (1 ft^3 each, shaped to the footptint of the Fonken). Looked like a shrunken head sitting on the woofers, but even with a 100 Hz (2nd order active) XO they did well in my big room, being able to play louder without strain than expected.

Actually on the latter, i have had the uFonekn playing in my BIG room alll by themselves and people asking, "are the woofers playing" (fully expecting them to be when they weren't)



dave

[strider75]

Originally posted by chrisb
.

aye, there's the rub -

What we ended up with as XO for the Tysen/uFonken was high enough ( 300Hz - ish) that stereo woofers ( can't really call them "subs") were mandatory, and was also beyond the range of built-in filters of any plate amp we could find. No big loss there, as the filters in most budget plate amps is definitely not their best feature.

The Tysens's have a single, side firing, SDX7 IIRC? Do you find that there are any issues with the bass sounding un-natural in it's presentation with the combination of the side firing driver and the relatively high XO point? When I say the XO point is high I'm assuming that what I've read WRT being able to localize signals above the mid 100 hz range is true....