Wilson Alexandria XLF Measurements "Quite Poor"

[Steve Williams]

Wow,..... just looked at A-gon. Never seen so many X-2 and Sasha's up for sale.

Are the Sasha owners upgrading to the Alexia and the X-2 owers going to the XLF? Hmmmmmmmmmmmm

Maybe Dave has a hit with that new tweeter!

Most of the X-2's for sale are from dealers

 

[microstrip]

Hello Micro

Well here are two in-room averaged graphs. I own a pair of the JBL 1400 Arrays. From an engineering standpoint which do you think will be more neutral to the source?? The Arrays are flat inroom because they were designed that way just as the Wilsons are not. The Arrays are also pretty flat on axis asside from the the "hot" tweeter.

The way to avoid flat failing apart is to have the speakers be a constant/controlled directivity design

Rob

Rob,

You should make clear if you are a anechoic or a inroom averaged "flat lander" . Otherwise we are comparing apples with oranges. FIY I am posting the anechoic on axis response of the JBL 1400 arrays.

BTW, I find funny when people argument using a statement having the words "aside from" ...

 

[mep]

Alright, how many people here own either X2 or XLF speakers and don't like the way they sound and are bothered by the measurements? Now how many armchair quarterbacks are here that haven't owned or heard the X2 or XLF and are bothered by the measurements?

Just what I thought...

 

[A.wayne]

Well played Micro , excellent serve sir ... Lol

 

[Robh3606]

Rob,

You should make clear if you are a anechoic or a in room averaged "flat lander" . Otherwise we are comparing apples with oranges. FIY I am posting the anechoic on axis response of the JBL 1400 arrays.

BTW, I find funny when people argument using a statement having the words "aside from" ...

Hello Micro

The measurement you posted is not a true anechoic measurement it is a gated spliced measurement that suffers from artifacts. Fortunately JBL has an anechoic chamber so I know what the system actually measures like under those conditions.

I am an in room and anechoic flatlander.

Aside from?? Well designs are about compromise so either they have a rise on axis so it's flat averaged or they keep it flat and have a dip in thr averaged room response.

Attached are JBL's anechoic measurements.

 

[Imperial]

5db and 7db dips in the tweeter? It must be reflective issues caused by the Horn section/baffle or something?
(microphone anomaly..)
See, even the JBL when measured does not show what you will actually hear when seated in the listening position!
I've heard a JBL 1400 driver by Arc gear and it is as neutral as a pool of clear water! No dips!

Mvh

 

[microstrip]

Well played Micro , excellent serve sir ... Lol

But now some serious stuff: my own measurements of the response in room of the X2 using REW and an ECM8000. They should be considered as raw data, with severe limitations and are in no way representative of X2 performance or specifications. But I hope those with good will see my point.
These responses were all taken with the microphone at the central position 11 feet from the speakers and 36" height , but I was moving the speakers about one feet from the from the front wall between each data taking. Minimum distance was around 4 feet. I tried to reproduce the vertical scaling of the Stereophile measurements (5dB division, 50 dB range) and used 1/6 octave smoothing to allow an easy comparison. Enjoy!

Yes, I am now dealing with the 800-900 Hz zone now, I hope next run will look nicer.

 

[andromedaaudio]

micro No sign of a mid high XO here , slight downslope as well , i like that too as do many

 

[Imperial]

Microstrip, that is just a flat out impressive curve!!! The dude that installed your set really got the tweeter resistor just bang on!
(or something.. )

Mvh

 

[FrantzM]

But now some serious stuff: my own measurements of the response in room of the X2 using REW and an ECM8000. They should be considered as raw data, with severe limitations and are in no way representative of X2 performance or specifications. But I hope those with good will see my point.
These responses were all taken with the microphone at the central position 11 feet from the speakers and 36" height , but I was moving the speakers about one feet from the from the front wall between each data taking. Minimum distance was around 4 feet. I tried to reproduce the vertical scaling of the Stereophile measurements (5dB division, 50 dB range) and used 1/6 octave smoothing to allow an easy comparison. Enjoy!

Yes, I am now dealing with the 800-900 Hz zone now, I hope next run will look nicer.

Hi

I know that when measurements are not good the explanations and excuses machine works overtime ..

These are cases that show how a good speaker measure in a good room. IOW Very, very good measurements. Please ! but please leave the darn things alone .. Drop two subs (or even better a stereo IB pair ) and be done for a few years .

 

[andromedaaudio]

Micro have you tried dampening the mid a little and measure.

I think in wilson terms that is adding a resistor with higher value

 

[A.wayne]

I would like to see a full curve before commenting, preliminary between this and the stereophile curves a picture emerges , hmm if it holds true obvious what Wilson is doing ..

Sly indeed ..

If true , he has sacrificed everything for summations at a fixed seated position ...

Measurements tells you everything , there's always a story ....!!!

 

[asiufy]

the listening position for the X-2 or XLF must be a minimum of 9 feet for the aspherical propogation delay to be effective

Steve,

Correct me if I'm wrong, but Fremer's review says he was sitting 94" from the XLF. And that 94" < 9 feet Yet the Wilson guy that did the setup claimed it would work, even better than the Maxx 3 that was sitting there before...



alexandre

 

[andromedaaudio]

Another approach could be , reduce the resistor value of the woofer(s) and the tweeter if possible , to bring them up in the overal response thus reducing the " mid" bump

Micro have you tried dampening the mid a little and measure.

I think in wilson terms that is adding a resistor with higher value

 

[LL21]

But now some serious stuff: my own measurements of the response in room of the X2 using REW and an ECM8000. Enjoy!

Yes, I am now dealing with the 800-900 Hz zone now, I hope next run will look nicer.

Nice graph for such an early start in your setup! What does it look like below 200hz? Look forward to subsequent graphs...hard work!

 

[andromedaaudio]

Actually JA answers this whole topic discussion himself as i read the measurements more carefully , its all about distance,....i reckon

Above 250Hz, the XLFs' response in the Innovative listening room meets very tight limits: ±1.5dB. Again, small response peaks are balanced by small dips, but the response trend between 250Hz and 6kHz is a little flatter than in Michael's room. This may well be due to the greater distance to the listening position at Innovative: 128" vs 94".

Steve,

Correct me if I'm wrong, but Fremer's review says he was sitting 94" from the XLF. And that 94" < 9 feet Yet the Wilson guy that did the setup claimed it would work, even better than the Maxx 3 that was sitting there before...



alexandre

.....but its not that easy to drive as the X2 .

 

[A.wayne]

Steve,

Correct me if I'm wrong, but Fremer's review says he was sitting 94" from the XLF. And that 94" < 9 feet Yet the Wilson guy that did the setup claimed it would work, even better than the Maxx 3 that was sitting there before...



alexandre

Shhhh....

 

[LL21]

...Above 250Hz, the XLFs' response in the Innovative listening room meets very tight limits: ±1.5dB... .

wow...

...but its not that easy to drive as the X2 .

...is it that much tougher to drive? Still works with Lamm SETs?

 

[microstrip]

Nice graph for such an early start in your setup! What does it look like below 200hz? Look forward to subsequent graphs...hard work!

As Amir would wisely say, the frequency response bellow the transition zone (around 150-200 Hz in my room) using such large speakers is mainly due to room dimensions and speaker placement. Interestingly, the results I got with the X2 are within a couple of dB what I got with the Aida or the Martin Logan Descent in similar positions. Because the room is very long I get significant response down to 15 Hz, but depending on placement a few deeps due to room cancellation modes show in the graphs. I have decided not shown it in this thread, as it is mostly a characteristic of the room, and in a thread with this tittle it will most probably be misunderstood by most readers. My apologies for those asking to see these graphs.

Please see that even David Wilson agrees with me. Quoted from the X2 manual :
Long, narrow, rectangular rooms also pose their own special acoustical problems for speaker setup. They have the ability to create several standing wave nodes, which will have different standing wave frequency exaggerations depending on where you are
sitting. Additionally, these long rooms are often quite lean in the bass near the center of the room

 

[A.wayne]

Baaaahhhh , fault , dupla falta, próximo servidor ......