All the Polk SDA upgrades located in one place!

gimpod

VR3 wrote: »

I figured this would help some folks find all the tweaks!

If I missed any, please let me know! Please let me know if there is a better link than the one I used as well!

Thanks!

http://vr3mods.com/LCSDAUpgrade.html

You may want to put this link in there too.

http://www.polkaudio.com/forums/showthread.php?118471-Current-Production-Vintage-Support

as of 04/14/2011

[Deleted User]

VR3 wrote: »

This is also a stick now at the top of the vintage section! Thanks Nap!

You're welcome. Re: The Bass Brace - a while back there was some question about it. I e-mailed Matthew Polk and he responded with some nice background info. I'll see if I can dig up that e-mail. Cheers. :cool:

[Deleted User]

Back Again. Found it.

What follows is from Matthew Polk regarding the Bass Brace:

Tony –

The “Bass-Brace” was introduced as a recommended modification for the SRS 1.2 and was available free for the asking. The kit was composed of nothing more than a piece of all-thread, ?” I think, with a t-nut for the back of the cabinet and an selection of wall anchors. All late production SRS models came with the t-nut already installed in the back of the cabinet plugged with a bolt to seal the hole. (Note: when the all-thread is screwed into the cabinet it will often wind Dacron around it like cotton candy jamming in place and requiring removal of a driver to free-up.)



The “Bass-Brace” did make a noticeable difference in bass performance. Slam and speed were noticeably improved. If you anchored to a masonry wall the difference was really quite dramatic, more than you’d get from improving your speaker cables and even better than spikes.



However, the real reason for the Bass-Brace was not initially to improve performance. Around that time new industry safety guidelines were issued for loudspeakers which included a “tip test”. The tip test specified that with the speaker placed on an inclined plane at 10 deg. (as best I recall) it would not tip over in any orientation. Needless to say, the SRS products did not pass. That was a real problem and with an inventory of product already in the warehouse we needed a solution. The solution was the Bass-Brace which when installed prevents the speaker from tipping over. But, when trying it out we realized it also made a significant performance improvement. So, it became both a performance modification and a safety feature. However, it was very difficult to install and I doubt many SRS owners ever enjoyed the benefits. Over Amy’s objections I did install mine and anchored them to an 18” thick brick and masonry wall. It was very impressive.



Hope that helps



-msp

Hope this helps. :cool:

quickr1

anything for the ls 90? also in for the rt series.

Drenis

I wonder if there would be any benefits to doing this mod to a 3.1TL series SRS speaker... I may experiment sometime down the road.