Will cane grill cloth block highs?

[Mr. Widget]

Also, I believe that every doubling in distance from the speaker results in -6 dB, correct?

John

Yes... in a lossless perfect world.


Widget

[johnaec]

Yes... in a lossless perfect world.

What - doesn't everyone set their rooms up anechoic??

John

[Mr. Widget]

Greg,

This one is for you. I remembered that I had a pair of Klipsch Heresy IIs in storage. Here are the effects of the Klipsch Grille material on and off the newer horn tweeter. It certainly has much better HF extension than the old EV units.

Red Plot= no grille
Blue Plot= with grille

[Mr. Widget]

Now the bad news... not only is the bass super weak for a twelve incher, here are the 2nd and 3rd harmonic distortion plots of the Klipsch Heresy IIs. The input power was about 2 watts and I was worried about the woofers... I didn't have them frequency limited and the bass goes down to 10Hz.

The L100 had significantly less distortion and at a higher power level.

Blue= 2nd Harmonic raised 20dB
Green= 3rd Harmonic raised 20dB

[Mr. Widget]

Here is the L100 again for easy comparison.

[Steve Schell]

Y'know, that old plot of the T35 actually doesn't look that bad to me. If you consider 107dB as the average response, it is only about 6dB down at 15kHz. Not stellar performance, but not bad and certainly correctable with some mild EQ. The phenolic linen dome is well into mass rolloff above 10kHz., but is exhibiting good piston response and little if any breakup. These old EVs and the somewhat similar Jensen RP-302s sound very accurate and clean to me. I certainly prefer them to more recent designs that resonate the suspension to gain added response on top, and sound "tsss tsss" as a result. It really takes a ribbon design to move the mass break point high enough to achieve flat piston response to beyond 20kHz., but their overall sensitivity is quite a bit lower.

[sonofagun]

We built a pair of Klipschorns many years ago equipped with OEM E-V tweets. Found that a standard 2nd order x-over worked best rather than a first order (Harsh!). Guy who ended up with them said they sounded better than factory K'horns!

Mr. Gidget...just wondering if you would have tested the raffle L100s with and without my foam grilles in place?

If I send you some foam, would you like to run tests on it to post here?

[Mr. Widget]

If I send you some foam, would you like to run tests on it to post here?

I'd be happy to. It might be interesting to see if there is a difference between the "Quadrex" and plain foam. To me it looked like the heavy weave pattern of the Klipsch grille created a diffraction gradient... you can see how the response got bumpy, it wasn't simply rolled off.

Widget

[Mr. Widget]

Grumpy has sharp eyes. The Klipsch Heresy II is not as bad as it seems compared to the L100 as far as harmonic distortion is concerned. Between measuring the L100 and the Klipsch, I was measuring some speakers with much lower distortion and so I had raised the level even further... I forgot to reset it to 20dB. The JBL is still a bit better over much of the spectrum, but they are much closer in their distortion levels.

Widget

[tom57]

This is a plot of one of my L100s. .....The controls were both placed at the "Laboratory Standard" position... it did indeed produce the most linear response. ....

Widget

Hi, I found this interesting frequency plot from the L100. I am too using a pair of them.
Can you tell me what you mean with the "Laboratory Standard" position of the controls? Is it 5 on the scale (0..10)?

BR Tom

[Zilch]

"Search" knows the answer:

http://audioheritage.org/vbulletin/s...atory+standard

[tom57]

Great - thanks a lot - will use search next time first ;-)