LX521 revisited

[Deward Hastings]

iswith these driversin the recording

[fdieck]

Re: LX521 revisited

Thank you Mr. Hastings for you impressions and putting your ears where mouth is. I am not suprised at your obsevations about room difference since dipole work better with diffuse relective sufaces and the Burning Amp room picture looked like any thing but a diffuse room. As I believe you were member of the Berkely free speech movement I will respect your right to express your opinions in the future. Especially against the status quo.....
Fred


I don't who tacobandit is but.......

http://www.youtube.com/watch?v=3cUY9MaZQ4Y&feature=plcp

Exactly duplicate post here and at Diyaudio are in questionable taste, but I defend your right to do so.

[bohdan]

Re: LX521 revisited

We’ve still got a lot to learn about creating stable “auditory scenes”, and I expect the LX521 (or something like it) will play a significant role in learning and demonstrating what it is.

Hi Deward,

I am glad, that spatial issues in loudspeakers are finally being considered as important.

http://www.bodziosoftware.com.au/Att...udspeakers.pdf

Best Regards,
Bohdan

[fdieck]

Re: LX521 revisited

Hi Deward,

I am glad, that spatial issues in loudspeakers are finally being considered as important.

http://www.bodziosoftware.com.au/Att...udspeakers.pdf

Best Regards,
Bohdan

Finally..........?

Baffle diffraction: Jon Dahlquist, Jim Theil, Richard Vandersteen and many others
Low order crossovers: Jim Theil, Richard Vandersteen, John Dunlavy, and many others.

The LX 521 maybe called First order, but I bet if you measure it it looks like a Second order LR. Linkwitz himself has stated it is 6 dB down at 1kHz and the drivers phase inverted....

[johnk...]

Re: LX521 revisited

When I set up the Note II with 1st order with phase tracking through the crossover the LP and HP poles had to be shifted considerably, with upper mid connected with reversed polarity. The phase response looks pretty much LR4 though, not LR2.



The version with the best looking impulse has an LR2 crossover for the coupler. After some extended listening with 1st, 2nd and 4th order crossovers I really can not say there is any big difference in the sound of my system, but the 10F is certainly working harder with the 1st order whcih is very obvious from toughing the cone, and in that regard alone I would still suggest that higher order is a better choice, though I see some things in the CSD plots on my system that suggest 2nd order may be the superior configuration over 4th order. I have yet to measure the polar response with the 1st and 2nd order configurations. Probably do that tomorrow.

CSD plots are presented at the bottom of my News page.

[johnk...]

Re: LX521 revisited

Second, regarding issues of the midrange crossover and driver integration . . . I had heard no problem with that at BurningAmp, but it has been suggested that there might be some, and that, more than anything else, is what I went to listen for. Put it to rest, there iswith these drivers.

See my response to fdierk about the phase of the 1st order.

in the recording

I like that, "they ruthlessly expose problems", spoken like a typical reviewer. Why would you expect anything else from stereo? There is only one optimum position for creation of a phantom image and that is centered between the speakers. Sit anywhere else and there is necessarily degradation in the image.

By the way, is classical music all you guys listen to? How about some Jazz or contempory or some good old Rock and Roll How does the LX521 sound with Little Feat at 95 to 100dB?

[Whitneyville1]

Re: LX521 revisited

Deward gave us his subjective opinion on the LX521's, and although I doubt I'll ever have the money to use them, I value his input. The crossover order may be more dependent on the driver you're crossing from than the LX's characteristics. It's not "the perfect tweeter" because that hasn't be created yet. ;)

[fdieck]

Re: LX521 revisited

See my response to fdierk about the phase of the 1st order.



I like that, "they ruthlessly expose problems", spoken like a typical reviewer. Why would you expect anything else from stereo? There is only one optimum position for creation of a phantom image and that is centered between the speakers. Sit anywhere else and there is necessarily degradation in the image.

By the way, is classical music all you guys listen to? How about some Jazz or contempory or some good old Rock and Roll How does the LX521 sound with Little Feat at 95 to 100dB?

Ah... you are making me miss my design review days (as long as I was not the designer in the hot seat) . I really don't see how one can call a design with out of phase driver connections and -6dB at crossover point, anything but a (quasi) 2nd order LR response. When you factor in baffle roll off (or defraction), driver roll off, and driver directionality; call something First Order is more semantics than reality. Second order sounds like good compromise to me.

PS Any speaker that permits one to sit still while listening to Lowell George sing "Fatman in the Bathtub" is fatally flawed.

[charlielaub]

Re: LX521 revisited

...Little Feat at 95 to 100dB?

+1

[Deward Hastings]

Re: LX521 revisited

By the way, is classical music all you guys listen to? How about some Jazz or contempory

The selections SL played were. I cannot evaluate speakers (at this level of quality) without reference to an "original source" that I am familiar with. Otherwise the evaluation is entirely "subjective" . . . whether I "like" the particular sound coloration (or lack of) or not. Back when I was working rock and bluegrass I could have told you whether a recording sounded like "house sound" (hopefully not :eek but could not in any case say whether a studio mix sounded "real". What was played certainly sounded pleasant enough . . .

I seriously considered bringing my "Accordion Babes" CD, but that wasn't what I went to listen for . . . :D
http://accordionpinupcalendar.com/2011_gallery.html

[Deward Hastings]

Re: LX521 revisited

After some extended listening with 1st, 2nd and 4th order crossovers I really can not say there is any big difference in the sound of my system, but the 10F is certainly working harder with the 1st order whcih is very obvious from toughing the cone

As I replied over at DIYaudio, I don't know what you are doing that is different from what SL is doing, but "excessive excursion" is simply not an issue with the LX521. The cones on the drivers in LX521 are well behaved far enough out from crossover that the benefit of higher out-of-band suppression (necessary, for example, with the W22) just isn't there. With many drivers I'd expect higher order to sound better for that reason (stop-band suppression) alone. Imaging is possibly helped by the lower phase shift of the lower order filter . . . at very least it's one less confounding variable to worry about. What we perceive, even how we perceive, in the critical midband is still an open area of study. The motors and suspension of both drivers are obviously quite good, and seem well matched and balanced for the application. There may be some room for improvement, but I'd expect it to be modest.

Initial shipment of the custom "SL" drivers is promised RSN, although until there is sufficient supply they may be reserved for licensed builders. Once they are available you might want to get a set . . . the baffle dimensions can be easily figured from a photograph (especially if you think like an engineer ;)) . . . and then repeat your crossover experiment with them.

[Deward Hastings]

Re: LX521 revisited

I really don't see how one can call a design with out of phase driver connections and -6dB at crossover point, anything but a (quasi) 2nd order LR response.

I suppose you can call it anything you want . . . especially if you chose to include "baffle effects", but the actual physical crossover is one cap and one inductor, and the drivers are both admirably flat at least a couple octaves either side of the crossover point. If you call it "quasi second order" then I suppose that SL's design matches John's determination that "2nd order sounds best".

[Whitneyville1]

Re: LX521 revisited

Deward, do you have any information on what the cross-over frequency (or range) on the LX is suggested? I'm just curious.

[Deward Hastings]

Re: LX521 revisited

Deward, do you have any information on what the cross-over frequency (or range) on the LX is suggested?

"Actual" depends on what you measure because of equalization and acoustic effects, but nominally it's 120 Hz for the W/M, 1000 Hz. for the M/M, and 7000 Hz. for the M/T. The dual mids obviously cover a substantial range. There's more information at http://www.linkwitzlab.com/LX521/Description.htm but for more detail, like ASP circuits and response curves, you'd have to buy the plans.

[Whitneyville1]

Re: LX521 revisited

Somewhat "flies in the face" of conventional speaker design, doesn't it? Does take a little power too. Makes me wonder wat' Mick an' th' lads wud soun' lak' on 'em doin' "Honky Tonk Women" tho'. You really need to sneak a CD like that into one of those auditions, just to raise some eyebrows and heart-rates. I made a reservation at SON, our snob audio store here, and brought some LP's with me, and I slipped my Hank Williams Sr. on the Pink Triangle after my UHQR of DSOTM, and I thought the "host" was going to die! A $95,000 stereo system with Hank Sr. on it, yodeling no less!:p