[DMurphy]

thing again, since I had a rehearsal canceled for fear of 1/4th inch of snow.  Stuff like that can shut down the Beltway.   Anyhow, I treated one of the two Seas CA15 woofers I use in my CA0W1 2-way, and Jim's Song Tower.  That was after I listened to them untreated, running full range in the CA0W1 cabinets.  The CA15 is an exceptionally smooth unit with no breakup to speak of, so the full-range sound is very uncolored.  I used my remote-controlled A-B switch box and the CD used at the 2007 Iowa DIY, which has a wide range of selections, rock, classical, gospel, jazz--just about everything except heavy metal.  I couldn't hear any difference between the untreated speakers.  I then wrapped clay around all of the ribs and rings on one of the CA15's, and also put a heavy wad on the rim, which acted as an extra gasket.  The CA15 has a heavy metal cast frame to start with, so it's not like I was damping down a flimsy stamped job.  I listened again carefully, over and over, and I honestly didn't hear any difference.  I switched over to an HT2 I had hooked up, and it sounded a lot better.  But the two CA15's--dead ringers (or non-ringers) as far as I could tell.  I did this once before with the smaller version of the CA15's--CA12's.  I thought I did hear a difference then, but I was using open backed cabinets stuffed with poly fill.  It could be that the clay was reducing the back wave a little, and that's why the treated woofer seemed to have a little more presence.  But there's no doubt about the CA15's--the clay didn't make any difference.  I was disappointed, because I'm always looking for a cheap upgrade.  Dang.

[Big Red Machine]

I'll replace you as Jim's ears then.  Now where is my soldering iron?   

Nathan and I both heard a delta.  Still can't say better or worse, but certainly different.  I am not losing any sleep over it though.  And I'm too lazy to remove the clay now that it is in place.

[Tone Depth]

From what I've read, the clay is more effective at damping out midrange frequencies than low frequencies, picked up by the basket.

"Again Dennis and or Jim, I urge you to try this on the midrange basket of a HT3 or Songtower.  It is a very easy and inexpensive way to build a better speaker.  The sonic result can most accurately be described as having stuff that was obvioulsy not supposed to be there go away, leaving more of the music, less garbage, and better sound."

[avahifi]

Thanks for trying Dennis.  However, I would expect much more effective results on a midrange driver than on a woofer.  Then I suspect the results would be measurable.

Best regards,

Frank Van Alstine

[DMurphy]

Thanks for trying Dennis.  However, I would expect much more effective results on a midrange driver than on a woofer.  Then I suspect the results would be measurable.

Best regards,

Frank Van Alstine

The CA15 is a midrange driver that also happens to go down to around 50 Hz and up to about 10 kHz.  I was running it full range, which means that it was producing more frequencies, both high and low, than a "midrange" would if it were band limited by the crossover.  That's why I chose the CA15, and used it without a crossover.  If there were any advantage in any frequency spectrum, it should have been audible. 

[avahifi]

OK Dennis, given the conditions you tested, it was a fair trial.  I wonder what was different with the setup you tried and with several others I (and others) have tried that did make a difference.  Again, I was not hearing things that were not there, B&W confirmed the results in their lab too.

Win some, loose some, but thanks for your willingness to try it.

Best regards,

Frank Van Alstine

[fishinbob]

Dennis- thanks for putting this one to bed. My feeling of complacency has set back in nicely.
To think that a few gobs of clay would transform my SongTowers sort of sounded like a mixed blessing anyway.
  Green thumbs up to BRM for his efforts too.

[DMurphy]

Dennis- thanks for putting this one to bed. My feeling of complacency has set back in nicely.
To think that a few gobs of clay would transform my SongTowers sort of sounded like a mixed blessing anyway.
  Green thumbs up to BRM for his efforts too.

Well, I'm not sure I've put it to bed.  My two trials were mixed.  And it's not like Frank doesn't have a critical ear.  I'm planning a DIY gathering in May--maybe I'll repeat the experiment before a larger crowd.  I'm open to the choice of driver and use, non-use of a crossover. 

[Big Red Machine]

I'll send you my magic green clay.  I have some brown and red as well, but they are for lower octaves.

[DMurphy]

I'll send you my magic green clay.  I have some brown and red as well, but they are for lower octaves.

Well that explains it.  My clay was a pale neutral color.  By all means send me the good stuff.