SDA Poly fill

sheathensemble

Just curious as to if anyone has stuffed their SDA's. Fill with poly fill? Possibly even some Rock wool or fiberglass?

I have sda1c's, and they have a very minimal amount of poly fill behind the mids...

So has anyone gone down this road? had any luck?

Denzel

Any additional polyfill or dampnig materials would hinder the low frequency performance of the passive radiator. I would suggest adding Dynamat to the baskets of your mid drivers and see what improvements you get there. I modded my SDA 2.3's back in December and made all the following additional modifications and was extremely pleased. Sealng the edges around the mid driver & tweeter mounts will help as well, use Mortite on the inner edge of the mid drivers and on the inside edge of the tweeters, it doesn't seem lke much, but there are serious appreciable improvements to the low & mid tonal quality of the SDA's by sealing them properly. Good luck!

drumminman

Denzel wrote: »

Any additional polyfill or dampnig materials would hinder the low frequency performance of the passive radiator. I would suggest adding Dynamat to the baskets of your mid drivers and see what improvements you get there. I modded my SDA 2.3's back in December and made all the following additional modifications and was extremely pleased. Sealng the edges around the mid driver & tweeter mounts will help as well, use Mortite on the inner edge of the mid drivers and on the inside edge of the tweeters, it doesn't seem lke much, but there are serious appreciable improvements to the low & mid tonal quality of the SDA's by sealing them properly. Good luck!

Adding more polyfill will only decrease PR output if you position below the MW's. Polyfill should never be at the same level as the PR.

A huge improvement I made was using Black Hole 5 instead of more fiber fill. I cut two 4" wide by 24" long strips and positioned them vertically behind each bank of MW's on the back wall in my 2.3TL's. I then placed three 4" wide strips horizontally behind the tweeters, connecting the two vertical strips making an "H".

The effect is it took congestion out of the mid range, making it sound like my amp had more power.

See this post for a more complete write up: http://www.polkaudio.com/forums/showthread.php?128159-Black-Hole&highlight=drumminman

sheathensemble

Ok thanks for the heads up. I figured these sda 1c's were a different beast when it came to this topic. I am thinking of mounting rock wool on the back wall of the speaker behind everything but the PR. I have used rock wool with great success in quite a few speakers. Thanks a bunch guys, you just saved me a lot of money on poly fill and even some precious time.:cheesygrin: I will post regarding the difference in sound and quantity used in a few days when install the rock wool.

sheathensemble

Well been there done that...

I put a small amount in behind the tweeters and mids...

not really the result I was looking for... I don't suggest doing this mod

Denzel

I would try the dynamat, goes on the baskets of the mid drivers and passive radiator. Seems to be a popular md here and I had good results on my SRS 2.3's.

TennMan

drumminman wrote: »

Adding more polyfill will only decrease PR output if you position below the MW's. Polyfill should never be at the same level as the PR.

My 10Bs came from the factory with about 2" covering the back wall of the speaker from top to bottom behind the MWs and the PR. Are you saying that it should be removed completely behind the PR or just don't add to what is there?

It has about 4" behind the tweeter.

Joe08867

I have never seen it go all the way down to the PR. It may have shifted Tennman.

To Sheath, The dynamat suggestion is a good one. I would also suggest running a 4" wide strip down both of the inside side walls (Not the back wall at all) of the cab. It eliminates any cabinet vibration and tightens up the low end.

drumminman

TennMan wrote: »

My 10Bs came from the factory with about 2" covering the back wall of the speaker from top to bottom behind the MWs and the PR. Are you saying that it should be removed completely behind the PR or just don't add to what is there?

It has about 4" behind the tweeter.

I think Joe is right, it probably shifted. When I refurbished my RTA 12C's last year I found the same thing: the polyfill had shifted and fallen to the floor of the cabinet so it was behind the PR. I repositioned it and the bass slam was better.

TennMan

The pollyfill isn't on the bottom (floor) of the speaker. It covers the entire rear of the speaker from the tweeter to the floor. Is that the was it should be? I understood him to say there shouldn't be any behind the PR at all. Exactly were should pollyfill be located? Thanks for the input.

Joe08867

On mine I was told that it should be accross the top and down the back above the PR. And once I did that the bass became cleaner and tighter and like drumminman said the slam was there.

PolkMaster1

drumminman wrote: »

Adding more polyfill will only decrease PR output if you position below the MW's. Polyfill should never be at the same level as the PR.

A huge improvement I made was using Black Hole 5 instead of more fiber fill. I cut two 4" wide by 24" long strips and positioned them vertically behind each bank of MW's on the back wall in my 2.3TL's. I then placed three 4" wide strips horizontally behind the tweeters, connecting the two vertical strips making an "H".

The effect is it took congestion out of the mid range, making it sound like my amp had more power.

See this post for a more complete write up: http://www.polkaudio.com/forums/showthread.php?128159-Black-Hole&highlight=drumminman

Drumminman -

I was the one who did a complete writeup on applying BlackHole 5 to the SDA-SRS 1.2 TL Speakers some 16 months ago. I applied it only to the back wall of the mid-range section. I did not apply any additional BH5 to the side walls or behind the tweeters. Have you tried BH5 just behind the walls and then apply additional filler to the sides and/or behind the tweeter wall as you mentioned above? If so, what was your results?

sheathensemble

Thanks for the input guys, I just want to let you know where I stand now.

I originally had put rock wool 1.5" thick in bags behind the mids and tweeters. Didn't like it to say the least. So i decided to just pull the stuff from behind the mids and leave the piece behind the tweeters in place. I don't know how much of a difference it made if any, because of the order I did things in... but I can say it sounds pretty good.

I might have to give Dynamat a try!:cheesygrin:

Cheers!

F1nut

I might have to give Dynamat a try!

You want Dynamat Extreme and it only goes on the driver/PR baskets.

drumminman

PolkMaster1 wrote: »

Drumminman -

I was the one who did a complete writeup on applying BlackHole 5 to the SDA-SRS 1.2 TL Speakers some 16 months ago. I applied it only to the back wall of the mid-range section. I did not apply any additional BH5 to the side walls or behind the tweeters. Have you tried BH5 just behind the walls and then apply additional filler to the sides and/or behind the tweeter wall as you mentioned above? If so, what was your results?

Sorry for the late reply - I applied BH5 only to the back wall, directly opposite the MW's and tweeters in an "H" pattern with a crossing piece behind each tweeter and the vertical strips behind each bank of MW's. I did not apply below the level of the lowest MW or to the side walls. From the experience of a couple forum members too much just sucked the life out of the sound quality. I did put back all the polyfill that came in the speakers and positioned it above the PR.

The resulting improvement in sound quality was easy to hear: an improved midrange most apparent with vocals and complex passages. More resolving, truer timbre of instruments and voices, and clearer at higher volumes. Made it sound like I had upgraded my amp!

I haven't hear any negatives with this mod.