Polk Audio SDA compact reference system

Spider removal would change the physical parameters and also let the cone flop. It is part and parcel of the suspension of the cone.
Ok, well I guess I should brush up on my speakers individual components..... But, I think I have gotten the gist of this procedure! Funny I haven't read about this stuff for other brands of speakers? Is the basket ringing inherent to only Polk?
 
Ok, well I guess I should brush up on my speakers individual components..... But, I think I have gotten the gist of this procedure! Funny I haven't read about this stuff for other brands of speakers? Is the basket ringing inherent to only Polk?
No. Here is a Boston Acoustics 10" woofer from an A200. Basically, most any stamped steel basket can be deadened with Dynamat.
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I like the glueing of the magnet as a fix for dried glue letting go as the original glue has aged poorly. The dynamat is more a psychological fix than a huge improvement. Yes, a speaker basket rings when tapped as an unmounted entity, but once it is mounted it no longer rings at the level it did, as it becomes part of the baffle structure and the resonance is now that of the full baffle, not an individual piece of thin metal. A channel beam is like a tuning fork by itself until it gets bolted to a stiffer structure.

I like dynamat for panels of electronics, car doors, trunk lids, etc. that tend to ring when struck, but the Polk midwoofers when mounted have a lower tink/thud when tapped. This goes against most the modders of these speakers, but there is no frequency response graphs backing up their claims, just "if it rings, it must be damped". It shouldn't hurt to dynamat, but again no response graph ever indicated a ringing was causing a bump in the frequency response in the first place. It has just become a defacto upgrade, due to its ease of application and it does deaden the ringing of each free air speaker. If the stamped frame was really an issue, Polk would have gone with cast baskets and they still use stamped metal today in many of their more recent speakers.
 
Dennis, I think the somewhat dulled down ringing when mounted is still problematic. I can't remember whether DK did his usual testing after doing this mod, but I'd be surprised if he didn't. Another thing to keep in mind is all the little tweaks have a cumulative effect.

The reason Polk still uses stamped steel baskets in their lower lines is cost. They do, however, use cast aluminum baskets in the TOTL LSiM's.
 
I certainly wouldn't approach any of the Polk upgrades expecting a "night and day" difference (I hate that term in audio). I upgraded three different SDAs in stages and took notes along the way to understand what differences I was getting. In my opinion, replacing the tweeters with the new RDO variants was the single most beneficial. Gluing the magnets is just good insurance. The rest are *arguably* not worth the time. They're fun and relatively easy and our brains are good at telling our ears that the time/money we spend is beneficial.

For my next set of SDAs, I'm going to replace the tweeters, glue the magnets, then sit back and enjoy them.
 
I certainly wouldn't approach any of the Polk upgrades expecting a "night and day" difference (I hate that term in audio). I upgraded three different SDAs in stages and took notes along the way to understand what differences I was getting. In my opinion, replacing the tweeters with the new RDO variants was the single most beneficial. Gluing the magnets is just good insurance. The rest are *arguably* not worth the time. They're fun and relatively easy and our brains are good at telling our ears that the time/money we spend is beneficial.

For my next set of SDAs, I'm going to replace the tweeters, glue the magnets, then sit back and enjoy them.

Sorry, upgrades are cumulative and are arguably worth the time and money. You didn't mention crossover upgrades, which are seriously worth the time and money as are Larry's rings, spikes and the Dreadnought.
 
I think "arguable" is the key term here. Lots of different opinions on the upgrade topic, just like the power amp topic.

I've done them all, including full crossover upgrades. However, full disclosure, I have a personal rule where I don't spend more on crossovers than I did on the speakers, so I haven't used any of those "exotic" caps. I'm just saying what I personally consider unnecessary (ie: not enough difference in sound to justify the cost/labor).

I forgot about the spikes though. Those were worth it for sure. To me, at least.
 
My crs (2 tweeter version) match perfect with my Sansui g-6700 at 90wpc. I do have a sub in line with them as well.
 
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