Some speakers slant, some don't. Why?

[esldude]

 

The squarewave from the Vandy isn't too bad.  Not as good as some Quads. Still quite good for a multi-way speaker.

 

 

 

Impulse response of the Vandy 2ce.

 

 

 

And for comparison the Quad Esl 63.

 

 

Of course in regards to super precise alignment, I do believe a 20% change in humidity will change points of focus due to change in the speed of sound more than 1/8th of an inch.   And a 2 degree change in temperature will make more difference than the humidity. 

 

[esldude]

4 minutes ago, Jud said:

 

Strange to me the Vandy would stop ringing quicker than the Quad.

 

I think an 1/8 inch movement by the listener may happen more often than 20% humidity changes or even 2 degree temperature changes.

 

Have any graphs for the Sound Labs or upline Vandys with built in amps?

Those were all from stereophile measurements, which I should have credited.  The old software would do that for links from Stereophile automatically.  They don't do impulse or squarewave more recently.  The Treo does show a nice step response which is near textbook.

 

Of course how important is that?  Here is the step response of some Revel Ultima Salon 2 speakers which sound quite fantastic by most accounts.  This step response is similar to that of all the Revel speakers.  Most of which get near universal acclaim for sounding good.

 

I believe the ESL63 had a resonance between the panel and metal cover around 13 khz which is why it rings on.  The later near identical design of the 989 did reduce that problem. 

[esldude]

8 hours ago, semente said:

 

Two (negative) aspects one should mention are the significant driver overlap and the ineffective control of the mid/mid-woofer resonance (plots from Sphile's measurements of the 2CeSigII):

 

 

The 2CeSigII also has a very bright in-room tonal balance, compared here to the PSB Synchrony One (which measures very flat in anechoic conditions) at JA's - bottom graph, though tis may or may not be related with the crossover design...

 

 

 

 

 

The Revel Ultima Salon2s also measure very flat in anechoic and in-room at JA's (blue):

 

 

Yes, the issues you point out are a result mainly of the choice to use 1st order crossovers in the Vandersteen.   The PSB uses steeper crossovers.  The step response is much like the Revel.  They use similar design philosophies.  Steep crossovers for optimum frequency response combined with even controlled off axis dispersion.  JA described the step response for the PSB and Revel with the same phrases:

Turning to the time domain, the PSB's step response is shown in fig.9. All the drive-units are connected with positive acoustic polarity, each one's step smoothly handing over to that of the next lower in frequency. This correlates with the excellent frequency-domain integration of their outputs noted earlier.
Read more at http://www.stereophile.com/content/psb-synchrony-one-loudspeaker-measurements#5hYgekL4FT23wPPe.99

 

 

JA's description of the Vandy 2CE:

In the time domain, despite the Vandersteen's multiway design, its impulse response (fig.7) is as time-coherent as that of the single-driver, crossoverless Fujitsu Ten Eclipse TD712z, reviewed elsewhere in this issue.
Read more at http://www.stereophile.com/content/vandersteen-2ce-signature-ii-loudspeaker-measurements#0eG5hLm0CRCwkWxG.99

 

The step response (fig.8) also features a time-coherent, right-triangle shape, though there is a rather faster decay than I expected.
Read more at http://www.stereophile.com/content/vandersteen-2ce-signature-ii-loudspeaker-measurements#0eG5hLm0CRCwkWxG.99

 

So one philosophy is to have very even responses, controlled off axis dispersion, and steep crossovers to control the drivers well with a step response that isn't time coherent.  The other is to allow wide driver overlap, and have time coherent response at least at some points in front of the speaker. This usually results in an uneven off axis response particularly above and below the listening axis. 

 

Both have their fans and adherents.  I've heard both sound good.

 

I would say I think the PSB/Revel/JBL approach seems to produce speakers which sound good easier with less fuss in more rooms.  Which one ultimately sounds best comes down to details of execution.  What information there is indicates our hearing in the upper frequencies at least is not fussy at all about phase or time coherence.  That leads me to think letting that go makes it much easier to produce a satisfying speaker.

[esldude]

7 hours ago, Jud said:

 

Thanks, esldude, informative as always.

 

Wish I knew how to read the "waterfall plots" that are so popular these days.

Here is a real simple explanation.

 

http://redspade-audio.blogspot.com/2011/05/rew-understanding-decay-and-waterfall.html

 

This one goes into more detail.

 

https://www.roomeqwizard.com/help/help_en-GB/html/graph_waterfall.html

[esldude]

3 hours ago, Ralf11 said:

True - somebody post up a plot for a bad speaker...

How about a Zu Audio Soul Supreme

 

[esldude]

9 minutes ago, Ralf11 said:

I'd heard they sound really good, but...

.......they measure really bad.

 

I have not heard any.  They don't appear on several fronts to be a good design for the money.

 

Now I built a speaker very similar to those once.  A transmission line with a single driver of decent quality also featuring a whizzer cone.  Dead center it actually had okay response from 50 hz to 18 khz.  A little away from dead center it still made 11 khz pretty well.  My cabinet was better braced than Zu's.  The driver was light and very efficient (I think it was 96 db for one watt).  Full range driver so no crossovers to worry with.

 

It could be enjoyable to listen to actually.  It was very dynamic and alive sounding.  A good match for the old tube integrated amps which is what I build it for in the first place.  Those things had 15-18 wpc or so.  That is also the market often praising Zu.  Low powered tube amp users.

 

So musical enjoyment such a thing can provide (our golden ears are more forgiving than we think sometimes).  It didn't take more than a few seconds to switch on the good rigs and hear how colored those speakers were.  Yet that never kept the DIY speakers from being a fun listen either. 

 

I think I still have those in the basement somewhere.  Maybe I should pull them out and measure them with REW or something.  Of course that might interfere with my Klipsch Heresy project for the basement sound system I have in mind.  Found a working pair of Heresy speakers for $5 at a yard sale.

[esldude]

27 minutes ago, Nikhil said:

 

Semente,

 

How do you interpret those graphs?  I can't make out the axis parameters.

Of the lot I really like those Graham Audio LS5/9 s - very engaging sound.

 

Regards.

 

  

 

Frequency along the x axis 20 hz to 20 khz on the right.

 

Time along y axis with 0 at the top and a bit over 200 milliseconds along the bottom.  The right hand side indicates decibel level with color.

 

Normally I see those rotated 90 degrees from this orientation, but there is no standard for that.

 

Ideal would be a narrow band of red and yellow very near the top dropping to black quickly.  A 2D variation on the info contained in 3 D waterfall plots.