"Xenum" (Audinum2) 2nd simulation... *PIC*

[Wolf]

http://i18.photobucket.com/albums/b117/wolf_teeth_speaker/Audinum%20Theater/Xenum.jpg


This is ssooooooo much better. I eliminated the notch and placed a zobel instead. I went with the AR-SXO topology, and am still 12dB slope electrical, with BW3 acoustic. Null is about to 60dB. I forgot to click driver responses before I copied, but it is about 2.6kHz xover. I can repost the correct picture later. XT and Audinum and I get "Xenum"!!
Thanks for the advice!
Wolf

[Wolf]

[Andy_G]

http://members.optusnet.com.au/~gradds55/little_orange_guy.gif

[Wolf]

This isn't really that complex either. I'll post the schematic shortly...
Later,
Wolf

[Andy_G]

> This isn't really that complex either. I'll
> post the schematic shortly...
> Later,
> Wolf

The XT tweeters seem to really like the ARSXO. ;-))

[Wolf]

http://i18.photobucket.com/albums/b117/wolf_teeth_speaker/Audinum%20Theater/XenumRev2-Invert.jpg


Here's how it currently sits. ARSXO12/18zobel. The impedance spike will be -25dB, so I don't think it'll be an issue this time!

In the Scandivifia project with the XT25TG30, the cap on the tweeter was a 17uF roughly, and the impedance peak needed compensated, albeit lower in frequency position than this project. I think I'm safe.

Due to the fact that I like the XT tweeters, and this little mid, I think this'll be my choice for the revamp. Price is decent, the project will cost more than the initial one did, and a stand for the xover placement will be warranted this time, as I'm *very sure* it won't fit inside the cabs. As before, a sub will be preferred but not required, and CRT's should be avoided. Once I get a XT pair, I will update the progress. Thanks for looking!
Later,
Wolf

[Wolf]

> The XT tweeters seem to really like the
> ARSXO. ;-))

Thing is, the Scandivifias were inverted tweeter polarity, and this is normal polarity. Strange...
Later,
Wolf

[jkim]

> Thing is, the Scandivifias were inverted
> tweeter polarity, and this is normal
> polarity. Strange...
> Later,
> Wolf

The reason is that your Scandivifas were LR2 design (180 degrees out of phase) and now your Xenums are LR4 (360 degrees out of phase). In fact it is an asymmetric LR4 with a driver's rolloff is close to 3rd order due to the use of a flat baffle.

-jAy

[Wolf]

> The reason is that your Scandivifas were LR2
> design (180 degrees out of phase) and now
> your Xenums are LR4 (360 degrees out of
> phase). In fact it is an asymmetric LR4 with
> a driver's rolloff is close to 3rd order due
> to the use of a flat baffle.

> -jAy

But I listen to the Scans as if they were flat baffles too. They are listened to below the ear-level, and both drivers are flushed. The Xenum has a surfaced midbass, and a flushed tweeter in the sim. I guess I don't understand how a 3rd acoustic can be an LR4, and your explanation isn't different between the 2 designs, as they are listened to as a flat baffle.
Later,
Wolf

[jkim]

> But I listen to the Scans as if they were
> flat baffles too. They are listened to below
> the ear-level, and both drivers are flushed.
> The Xenum has a surfaced midbass, and a
> flushed tweeter in the sim. I guess I don't
> understand how a 3rd acoustic can be an LR4,
> and your explanation isn't different between
> the 2 designs, as they are listened to as a
> flat baffle.
> Later,
> Wolf

Most implementations of LR type xovers are not exactly LR2 or LR4. According to what you described about Scans (i.e., a bit elevated listening axis), they should be something between LR2 and BW3, with polarity reversed. If you understand how phase and polar responses change by acoustic rolloffs, you'll know what I mean.

The reason why a little loosened LR4 works well on a flat baffle is that due to the excess delay in the woofer's phase, a slightly shallower rolloff is required of either (or both) of the drivers to achieve better phase alignment (i.e., more symmetric polar response at tweeter axis). That's why.

-jAy

[Jeff B.]

> Most implementations of LR type xovers are
> not exactly LR2 or LR4. According to what
> you described about Scans (i.e., a bit
> elevated listening axis), they should be
> something between LR2 and BW3, with polarity
> reversed. If you understand how phase and
> polar responses change by acoustic rolloffs,
> you'll know what I mean.

> The reason why a little loosened LR4 works
> well on a flat baffle is that due to the
> excess delay in the woofer's phase, a
> slightly shallower rolloff is required of
> either (or both) of the drivers to achieve
> better phase alignment (i.e., more symmetric
> polar response at tweeter axis). That's why.

> -jAy

Yes Jay, you are correct, and I would assume your explanation to the reason for the polarity difference as well.

[Wolf]

> Yes Jay, you are correct, and I would assume
> your explanation to the reason for the
> polarity difference as well.

I learned something!
Thanks for the explanations, guys!
Later,
Wolf