SDA SRS new to me
Options
Comments
-
skipshot12 wrote: »It's very soft and will compress easily.
Those factory gaskets in all likelihood were the same or very close in thickness.
Got the original glue off the passive last night.
Gonna try the Armacell install tonight.
Is it an easy install, just go after it?
Any tips on trimming? Trim first then install or trim after it's on?
I did find the Dynamat much easier to install on passive. Trimmed after installed.
Probably the reason I ran out of it...
Well for the 4 rectangular pieces for the spokes or uprights if you prefer, definitely size them first and only trim if you goof up the install. Use a pair of hemostats. I prefer a curved pair I have. Make 2 cuts in the backing paper and remove the small area that will allow you to initially stick to the area adjacent to the spider. Dog ear back a couple corners to enable you to reach in with the hemostats and remove the rest of the liner and then smooth down with your finger in a way so as to not get any bubbles. I ended cutting pieces that were a tad oversized for the area near the spider between the spoke sections and trimmed them with a brand new Xacto blade.
Fold where the red lines are in photo:
I recommend cutting away the vestigial tabs with a dremel reinforced cutoff wheel. Red arrows show the foam between the spoke rectangles which I had to trim with my Xacto:
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Unless you are referring to Armacell gaskets, in which case never mind lol. Another option to Armacell gaskets would be this stuff from Hobby Lobby. You should be able to get 4 one piece gaskets from each sheet: https://www.hobbylobby.com/Crafts-Hobbies/Basic-Crafts/Craft-Foam/Black-Foam-Sheet---12"-x-18"-x-2mm/p/28626George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
-
What’s a bookmark?
That gives you an idea of my computer talents.
Hey Gearge.
Yes, I was asking about the gasket for the passive.
I think it was something from the factory with the glue to hold down the gasket.
Looked like someone made a boo boo on the gasket installation, it was turned about two inches.
All the v notches were in between the holes for the screws. Exactly in between.
Only gasket I’ve had to mess with.
All the rest were perfect and as good as new.
The gasket was actually crawling up the side up near the spokes in some places.
Even glued all the way up there.
Must have been a Monday job 🤪 -
Gardenstater wrote: »Unless you are referring to Armacell gaskets, in which case never mind lol. Another option to Armacell gaskets would be this stuff from Hobby Lobby. You should be able to get 4 one piece gaskets from each sheet: https://www.hobbylobby.com/Crafts-Hobbies/Basic-Crafts/Craft-Foam/Black-Foam-Sheet---12"-x-18"-x-2mm/p/28626
That stuff looks like it’s pretty close to the same thickness of the original gaskets. They’re like paper thin.
Doing the conversion the Armacell looks like it comes out @ 3.75 mm.
That stuff you linked is 2mm.
I would say that’s pretty close to the thickness of my original gaskets.
From what I’ve been reading, and seeing from pictures, most of the other people’s polk speaker gaskets are much thicker than these and…. They look like they’re made of some kind of rubber.
Mine are definitely not that thick and I’m not sure they’re made of rubber.
Seem like a very thin paper or fabric material, sure don’t feel or look like rubber.
Maybe they’re just so compressed that it seems that way to me?
-
WOW! Please take a photo!
My gaskets are all factory and were all adhesive on one side. Stuck good. They used a 3/8" wide tape (maybe 13/32"). On the NOS MW6500 I bought it appeared to be 1/16" thick. They overlap the ends and when it compresses you can't even perceive a difference in thickness where the overlap is. That's how thin and soft what they used is.
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Something like this in 0.063" and black would be great but unfortunately we'd have to do a group buy. Great company that only deals in large quantities.
https://www.tapejungle.com/products/single-sided-pvc-foam-tape-low-density-16sld.htmlGeorge / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Yours look a tad different…
I’m gonna say they must be 1/16th, or 3/64ths… 🤪 or some-ting.
I’ll pull one a take a pick.
I’ll also add a pic of one that someone else sent me of their MW gasket.
Let me know if it seems thicker and of some kind of rubber material…. -
Closed cell foam. Either rubber based or polymer based. Doesn't much matter. What matters is the density and psi to compress 25% spec and the initial thickness.
Think of how firm bubble wrap is initially compared to after all of it's cells have been popped. Extreme example.
Armacell is super soft and airy because they needed that for it to be effective as thermal insulation. Over time more and more of those cells will pop and it will take on more and more compression set. Then you will be able to tighten screws more and more. Takes time though. It starts out 1/8" thick after all.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
One more picture. We are treading on thin ice with the curmudgeons here 😜
This shows that, even with this thin soft original gasket material, the compression set thickness is much greater midway between the screws even after several decades. That means the psi was not even across the circumference. No bueno for best coupling.
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Gotcha…
My approach will be just to make contact with the Armacell.
Then tighten a little at a time. Ensuring I don’t lose a seal.
I’ll do this over a few days. Overkill cautiousness… probably.
But I want these SDA’s done right.
I have an interesting observation that I would like others to chime in on.
While doing my mechanical upgrades I have not stopped playing music thru my sda’s.
What I’ve noticed is I haven’t lost much in the bass while I’ve had drivers out for modding.
Even when the passive is out I had good bass extension. Not as tight as a complete speaker but, not much loss in extension to my ears.
I’m listening to my sda’s now. All drivers are in on the right speaker sept for the passive.
The sda is still moving lots of air and haven’t loss much of anything.
My take… what a well designed speaker! -
When I had the 1.2tl here the bass with the passive radiator out could definitely rattle the foundation but it was monotonous and slow- Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
-
Nevermind..
-
Just to give you another idea of what I would try if I personally were in the need of new gaskets (which I am not). This stuff is a similar material to Armacell but is maybe 1/10 the density and half the thickness and is "extra soft" 3.5 psi firmness @ 25% deflection. It is 3/4" wide on a 50ft roll but it would be easy to attach a razor blade to a piece of 1/4" plywood with spacers and slit it accurately right down the middle for 3/8" wide.
https://www.grainger.com/product/GRAINGER-APPROVED-EPDM-Neoprene-SBR-Strip-Flame-6YHD4
Not saying that Armacell is a complete disaster to use as a gasket, just think this would be better. Bring on the keyboard warriors lol.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Keyboard warriors, give me a break. How about you, have you used the armacell?
Have you used any of this stuff you keep expanding on?
I speak from experience on what I offer. I could wax poetic for days about all the "better" stuff this and that I've never used.
But the difference is I have flipping experience with the stuff I offer I've used it.
Period
Enjoy!
I'm out! -
Yeah I have to agree, Im all for experimenting, but all of the stuff the regulars recommend have bene tried and tested for decades. Is there better? Maybe, but dynamat extreme, etc is all well tested by most here.- Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
-
Ruh Roh. I like Dynamat Xtreme. I like Armacell. OK?
Found some interesting info on the Second Skin. Nice find pitdogg2 and did I say congratulations on that? Congratulations!
This shows that it has a resonant frequency that is lower than the other ones they tested. Interesting? Maybe to me because I'm a nerd that looks at technical data and physical properties etc. to the point that others find it annoying lol.
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Gardenstater wrote: »Ruh Roh. I like Dynamat Xtreme. I like Armacell. OK?
Found some interesting info on the Second Skin. Nice find pitdogg2 and did I say congratulations on that? Congratulations!
This shows that it has a resonant frequency that is lower than the other ones they tested. Interesting? Maybe to me because I'm a nerd that looks at technical data and physical properties etc. to the point that others find me annoying
Fixed it for ya
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Second skin was a product recommended by our car audio guys back in the day... can't remember their screen names. It is a good product.
In MY experience and your experience may vary! The knock offs of dynamat extreme have a long-term adhesion problem. You open your stuff up a year from now and it is delaminating everywhere.- Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit. -
So they recommended a product that falls off in time? Or you are saying it does not do that?
Always good to try to stick to products that are tried and true, but then where is the fun in discovering something better? How do you make improvements?
Sorry to ruffle feathers by doing that. Egos are fragile sometimes and it is easy for people to feel hurt.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Second skin for cars went on in a liquid/paste form from what I remember.
Nothing wrong with trying new products, I think the general concern is that new members will try these products and a few years from now have less than desirable results. Speakers as you know last decades... some of these products we are talking do not last decades and can create a huge mess.. IE mortite sticking to the cabinets/baskets, etc.- Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit. -
Years back there was a company that sold a Dynamat like product, but instead of an aluminum skin it was copper. I bought some to install on the lid on a piece of gear. Maybe a year or so down the road I had a reason to open it up again. To my dismay most of that product was coming off and dangerously close to shorting out the electronics. I removed all of it and installed the tried and true Dynamat Xtreme like I should have done in the first place.
Anyway, it's one thing to try new products/ideas, but it's another thing when those products/ideas are so far out in left field that they defy logic. Then there's the shoving those products/ideas down people's throats because your ego is bigger than the universe.
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
nooshinjohn wrote: »***F/A-18’s…. Lol
Wtf Jason? lolI disabled signatures. -
Great show.plastic_avatar wrote: »Holy forking shirtballs.
I disabled signatures. -
The Gear... Carver "Statement" Mono-blocks, Mcintosh C2300 Arcam AVR20, Oppo UDP-203 4K Blu-ray player, Sony XBR70x850B 4k, Polk Audio Legend L800 with height modules, L400 Center Channel Polk audio AB800 "in-wall" surrounds. Marantz MM7025 stereo amp. Simaudio Moon 680d DSD
“When once a Republic is corrupted, there is no possibility of remedying any of the growing evils but by removing the corruption and restoring its lost principles; every other correction is either useless or a new evil.”— Thomas Jefferson -
Gardenstater wrote: »One more picture. We are treading on thin ice with the curmudgeons here 😜
This shows that, even with this thin soft original gasket material, the compression set thickness is much greater midway between the screws even after several decades. That means the psi was not even across the circumference. No bueno for best coupling.
Is that an original gasket?
-
Years back there was a company that sold a Dynamat like product, but instead of an aluminum skin it was copper. I bought some to install on the lid on a piece of gear. Maybe a year or so down the road I had a reason to open it up again. To my dismay most of that product was coming off and dangerously close to shorting out the electronics. I removed all of it and installed the tried and true Dynamat Xtreme like I should have done in the first place.
Anyway, it's one thing to try new products/ideas, but it's another thing when those products/ideas are so far out in left field that they defy logic. Then there's the shoving those products/ideas down people's throats because your ego is bigger than the universe.
I hope the ballistic stuff doesn’t end up doing that…..
-
skipshot12 wrote: »Gardenstater wrote: »One more picture. We are treading on thin ice with the curmudgeons here 😜
This shows that, even with this thin soft original gasket material, the compression set thickness is much greater midway between the screws even after several decades. That means the psi was not even across the circumference. No bueno for best coupling.
Is that an original gasket?
Yessir. Original 1979. Very soft and relaxed is about 3/64" at midway between screws. Totally compressed to paper thickness at screws. My NOS 1999 is 1/32" at midway between screws and totally compressed at screws as well. As I recall, it was 1/16" thick before installation, for only about 8 mos.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
According to the original owner no driver's were ever taken out.
Pulled one MW... this is the only ruler I have to show thickness. It's @ the 32nd scale.
Here's what the gasket looks like.
Maybe it's just compressed?
-
Really close to putting my passive back in on the right speaker.
Did the sealing of the Passive compartment this morning.
