Must try MOD - Foam inside the stamped steel baskets - YES!

F1nut

So, up to 7 or 8 from maybe a few...LOL

plastic_avatar

1C preview cross-thread report

I'll wager I foamed my baskets to a point no one else has.

Preliminary bench report from 90 hours of burn-in for caps and Wuhans is positive.

Clarity and separation is great. I can only compare to my other speakers, but I'm impressed.

They don't sound lifeless. They're quite clear, with what I feel is the proper level of 'air' around instruments and voice. Spotify Premium (which I find has distortion on sections of all my music (streaming from my old iPhone on multiple sources, that isn't on Amazon Music).

Recording was a little close, but it's just an anecdotal response. I might very well do this mod to my Monitor 12, if I keep them.

Looking forward to actually A/B'ing the mod on my 5B.

Abrupt cut at the end.

https://youtu.be/TUlij8U4oKU

xschop

Sounds great through my XS-8TLs😉

benjaminlea

+1 Foamed my baskets too, heard an incredible difference in detail and clarity as many others who have done the mod have reported.

Vocals are clearer, with more separation. Instruments sound like they are being played in front of me. Strings, white noise, details in tracks that I’ve not ever heard before are now coming through. The sound I hear now is nuanced and I would describe it as almost delicate.

This $0 mod (thanks to a forum member sending me the foam) really elevated the listening experience for me.

Side note - If anyone has some BH5 they wanna trade for some SL2000’s pm me?

😂

bcwsrt

Well .... nice timing for this previously missed thread to come back to life out of nowhere after I just reinstalled my J-B Welded and Dynamated MWs this time last night. But, I suppose there's always another mod to consider/pursue to keep our hobby interesting.

plastic_avatar

[chuckles]

Well, if you keep giving them a listen right now as is, you can give a good comparison if you try this mod.

Warning!

For me, this was torture.

When I try to do fine motor control, I get 'essential' tremors. And this requires detail-oriented application.

The Armacel is really sticky. I used angled tweezers to set the pieces in place. I even put a thin strip of it around the top edge *below* the surround. (Doesn't impact or touch the surround at all.)

Anyhow.

Totally worth the... probably... 10 to 12 hours for me to do. Totally.

I expect a normal person to take half that time.

Gardenstater

@plastic_avatar Kind of like this:

plastic_avatar

Oh G/god(s)...

Nooooooooooooooo... I *hated* that game.

skipshot12

Not sure what your speakers sounded like before but, they sounded wonderful thru my earphones.
Well done....

plastic_avatar

Just so we know where this foam mod is on my end, in relation to whether or not it added negatively to how the box performs, my interior mods include:

- Armacel on all interior basket surfaces (where reachable, and in the upper ring below the surround)
- BH5 behind mws.
- Aluminized rubber pipe wrap on passive chamber walls.
- Same wrap (think of it as Dynamat lite) on exterior of all baskets.
- xschop's semi-rings on mws.

I know it's a difficult comparison, since there is no control in my observation. I'm only comparing to a similarly-structured model. And all we hear is the result of mods on a speaker with no reference.

I do know there is a definition on voices I did not expect. And right now I'm very pleased with that result.

More testing the next couple of days.

My biggest question is:

'If my speakers don't exhibit a negative with all that^, what are the chances the foam mod will mean worse sound for you?'

skipshot12

plastic_avatar wrote: »

Just so we know where this foam mod is on my end, in relation to whether or not it added negatively to how the box performs, my interior mods include:

- Armacel on all interior basket surfaces (where reachable, and in the upper ring below the surround)
- BH5 behind mws.
- Aluminized rubber pipe wrap on passive chamber walls.
- Same wrap (think of it as Dynamat lite) on exterior of all baskets.
- xschop's semi-rings on mws.

I know it's a difficult comparison, since there is no control in my observation. I'm only comparing to a similarly-structured model. And all we hear is the result of mods on a speaker with no reference.

I do know there is a definition on voices I did not expect. And right now I'm very pleased with that result.

More testing the next couple of days.

My biggest question is:

'If my speakers don't exhibit a negative with all that^, what are the chances the foam mod will mean worse sound for you?'

With what I heard no negatives but…. Damn you guys with this mod!
Do you know what kind of time this would be to do my SDA SRS’s?????

🤣

skipshot12

^ Regarding mods…. Today was a great day.
I thought I had my cabinets sealed very well with taking care of the seam joints. I was getting about 1-1/2-2 seconds on my passive pressure test.
Just got done with installing 1/4”x1” rubber fender washers to seal up the end caps on my sda’s. After installing those on my left speaker I did a post pressure test.
Now have the 3-5 second mw leak down others reported about 👍
Haven’t played any tunes yet to hear the difference. Gonna do the right speaker before a test listen.
Very excited to hear what this has done….
What a great day.

plastic_avatar

skipshot12 wrote: »

^
What a great day.

Hooray for you catching that.

I don't know about that particular test.

[goes to Google]

skipshot12

^ 👍

gp4jesus

@skipshot12

“… Aluminized rubber pipe wrap on passive chamber walls.”?

My plumber brother drew a blank. He did find it. IMHO having a reflective surface seems counter to what’s desirable in a speaker closure

Gardenstater

gp4jesus wrote: »

@plasticavatar

“… Aluminized rubber pipe wrap on passive chamber walls.”?

My plumber brother drew a blank. He did find it. IMHO having a reflective surface seems counter to what’s desirable in a speaker closure

@plasticavatar

Fixed it for you Tony

plastic_avatar

The walls are hard and wooden. They reflect.

The thin aluminum side of the wrap reflects, but differently than the wood. The rubber helps control resonant vibrations. To my ears, it helps tighten up low frequencies, without taking the bass away.

This is a contentious mod. I'll take more about it over in my thread

xschop

It's all about the thwack.

plastic_avatar

Speaker got thwack.

skipshot12

^ Shazaaaam…

plastic_avatar

Every time I see that frakking Operation picture up there I both die a little inside *and* laugh a little on the outside.

My family thought it was funny. Which says a lot about my family and how they treat me...

=P

https://www.youtube.com/watch?v=uq3IVfL69oI

Jazzhead

It's all about the thwack and the slam.

xschop

Al Capone and Eva Peron would agree.🙂

xschop

Bump for @melchionda

odcics2

Gardenstater wrote: »

I previously mentioned this in a couple of scattered places and didn't open up a dedicated thread. I suppose I didn't want to stick my neck out until there was confirmation from another who has tried it ✔. I've been living with this for almost 6 mos. now and I still continue to be super pleased with the benefits (I think the foam is still breaking in...kidding)! I used Armacell closed cell 1/8" thick foam but this is open to experimentation with perhaps open cell, composite of open cell over closed, felt over closed, felt alone......just keep it relatively thin like maybe 1/4" max(?). Let's get some more people trying this because it is a super rewarding mod and not all that difficult to do.

I won't get super long winded but I posted my initial report over in the other thread "What did you do to your stereo today" on p. 122.

https://forum.polkaudio.com/discussion/184609/what-did-you-do-to-your-stereo-rig-today/p122

Pictures are always worth more than words. I think the benefit of this is 3 fold: 1) Mechanical vibration dampening of the basket, 2) Sound proofing of the basket preventing acoustical into mechanical excitation, and 3) some amount of reflection attenuation of backwave reflections that would come back and hit the back of the cone. 3) is last but not least because when I did just one speaker initially I had to rebalance with whitenoise by lowering the unmodded speaker's channel by 0.4dB to compensate. I believe that is due to the reduction in reflected backwave which comes out as audible sPL through the cone. That has to be distorted due to time delays and phase differences and varying transmission/reflection for different frequencies.

Anyway, Merry Christmas and let's have fun with this mod. I'll add pictures when I find them.

Initial sizing on a spare driver I had. Settled on 1-1/4" x 1-5/16" but not super critical as long as you don't block the basket windows. You can even trim the windows with an Xacto knife after install:







Completed driver with the Armacell inside of the spokes and the section between spokes near the spider. I cut off the 3 vestigial tabs with a dremel cut off wheel - be careful not to get metal dust inside the driver:

Same idea, different execution.

Gardenstater

Ha! Yes, I believe I already posted those pictures earlier in this thread (or somewhere else maybe?). That is the Vandersteen midrange driver that came out of the patent I posted earlier in this thread.

odcics2

I believe you posted a currently available Scan Speak driver. Similar idea.
Here's a better pic showing the back side of an older Vandersteen 3A Signature midrange.
Note the thick green felt directly over the magnet.

Gardenstater

That's an interesting picture^ thanks.

I don't really remember what I posted where lol, but this is the article where I encountered those pictures of his midwoofer driver and the patented midrange driver:

https://www.ultraaudio.com/features/20090901.htm

https://www.ultraaudio.com/features/20091001.htm

odcics2

Ah, yes! I remember that article from 14 years ago!!
I think the 4.5” midrange driver is made by Vifa.

Gardenstater

odcics2 wrote: »

Ah, yes! I remember that article from 14 years ago!!
I think the 4.5” midrange driver is made by Vifa.

Yep. Confirmed.

https://www.stereophile.com/floorloudspeakers/128/index.html