Must try MOD - Foam inside the stamped steel baskets - YES!
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Guys... I love the passion but you are entering trolling territory
You’ve come at the wrong time. We were actually chasing the trolls away.Polk 7B’s modded
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He gave his experiences to share a positive outcome and got denegrated for it through a LOL.
I'm shocked that Polk went with stamped steel baskets on the new models I have seen, although they did try to make the geometry of the *uprights* so as not to reflect back at the cone so much, or at least that was my impression.
I hope we can keep this thread as a Check Your Egos at the Door zone.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 -
Sal Palooza
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The Thrifty Setups in Mah House Big thrifty stereo in the basement w/ my custom SDA-1C (built with help from kind forum members) * Beautiful 1966 MCM GE console upgraded w/ Bluetooth, Dual turntable, and Paradigm speakers in family room * Swanky 1980 Realistic system and great TEAC eq with dancing colored lights in the living room * Ye Olde college stereo in the garage -
There is a pic somewhere on the forum showing a base plate ripped from an MW frame. Been searching to no avail. I remember seeing it a couple years ago. Maybe in Vanilla archives?Don't take experimental gene therapies from known eugenicists.
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There is a pic somewhere on the forum showing a base plate ripped from an MW frame. Been searching to no avail. I remember seeing it a couple years ago. Maybe in Vanilla archives?
I'll look for it too. Pizza slice wedges of foam applied through that hole and stuck on underneath the spider if feasible. Would be super cool what effect that could have. But would VC have to be removed and re-installed ? I'm thinking yes but maybe you could try it on one of the ones you are working on that have fried VC's.
Just look at the rave reviews the KEF Meta tech is getting!
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 -
I'm thinking stuff the void/chamber with lamb's wool possibly?Don't take experimental gene therapies from known eugenicists.
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Hansvelton wrote: »
Par for course here at the CCP.Don't take experimental gene therapies from known eugenicists. -
Vandersteen mod is done and glue drying...
I would only do this to a burnt voice Midwoofer before replacing the coil itself. Good luck doing it any other way.
The MW 6500s have VERY little VC-baseplate gap clearance than all other MWs I've measured (1.070 vs 1.085), so I opened this one up to match all other MWs to prevent VC rubbing.
I added a little extra Power Grab to the central circumference to make sure the small voids around the protruding baseplate rivets filled in as I pressed it in. I simply scrolled it in and it went in without hassle and sits perfectly in the inner chamber on raised basket frame...
I cut the 1/8" thick PVA 2.50" OD and 1.1" ID using the same cutter I used on the phase plug felts.
The diagonal cut on the foam allows for final adjustment away from baseplate ID where Voice coil travels....
Don't take experimental gene therapies from known eugenicists. -
The spiders are remarkably gauze-like and therefore somewhat transparent to sound. I held one of my dismembered....disassembled baskets up to the direct sunlight coming in through the kitchen window and I could see through the spider into the space beneath including all the features thereof and it is pretty *cavernous*. I was surprised at that for a driver with a max excursion rating of around 3mm.
Can't wait to hear some listening impressions, however you may not have a XO that is compatible....?
PS: I wouldn't be surprised if the sound is more.......emotionally engaging.....with a touch of nutmeg even.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 -
I will wait til another burnt 6500 rears it's ugly voice coil lol
I will hold off from phase-plugging it until I get another donor.Don't take experimental gene therapies from known eugenicists. -
Gardenstater wrote: »The spiders are remarkably gauze-like and therefore somewhat transparent to sound. I held one of my dismembered....disassembled baskets up to the direct sunlight coming in through the kitchen window and I could see through the spider into the space beneath including all the features thereof and it is pretty *cavernous*. I was surprised at that for a driver with a max excursion rating of around 3mm.
Can't wait to hear some listening impressions, however you may not have a XO that is compatible....?
PS: I wouldn't be surprised if the sound is more.......emotionally engaging.....with a touch of nutmeg even.
Now that Ive dissected this thing, the spider and surround look and feel exactly like the 6510, which happens to be about same ohm DCR.
Don't take experimental gene therapies from known eugenicists. -
6500 is done, vestigial tabs evicted too...
Don't take experimental gene therapies from known eugenicists. -
... Regarding the basket acoustic treatment, I seem to recall some speaker baskets produced with a rough textured black undercoating type material on the outer basket...anyone? Also would like to see a before and after frequency response of just the basket treatment mod.
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Feel free.Also would like to see a before and after frequency response of just the basket treatment mod.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 -
... Regarding the basket acoustic treatment, I seem to recall some speaker baskets produced with a rough textured black undercoating type material on the outer basket...anyone?
Sounds like it is just a damping compound, trying to get a similar effect to what we're after with the Dynamat Xtreme or other similar product. I think Soundcoat is a material that comes in a can and can be rolled or brushed on. Could make a real mess if you weren't careful and it wouldn't be constrained layer damping because it wouldn't also have the aluminum layer on the outside.Also would like to see a before and after frequency response of just the basket treatment mod.
I'm assuming you mean the inside the basket sound absorbing material. It'd be technically interesting and I think you would see a difference if you had the right equipment and method but I doubt that you'd be able to look at the two curves and go.......see there.......look at the greater transparency and detail and separation of vocals and instruments. You have to use your ears for that.
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 -
Two weeks ago, I did this to one of my CRS speakers, both drivers. I don't have the ability to speak the way others do in regard to statements like, more air, etc. All I can say is this... After two weeks it's apparent that the speaker I didn't do this to has more "shout" to it. LOL, it sounds louder and mids are tad more in your face. The one that I did do this to is mellower sounding, which I like. And that's all I have to say.
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If your experience parallels mine, you will have the magic come in when you do the other speaker as well. Things need to be balanced. Let us know how it works out
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 -
I put my Monitor 4’s under the knife the other day. Figured since I was doing the whole Monte I’d give the inner foam thing a shot, just to see if it made any difference. Now, I did re-cap and damp the baskets with Noico all at the same time. Overall, I am just blown away how much better the speakers sound. Warm, but clear, tons of detail. Female vocals are lush. Norah Jones, more please. I’ll do my 7B’s when I do my rework of them and report back. Fun experiment. I think it has some merit! 🤘🏻
It’s in there, Armacell, kinda tricky to fish it in there but not too tough to do.
Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩 -
Pre & post mod measurements may parallel those of IC, speaker cables, and/or power cable upgrades/swapsAlso would like to see a before and after frequency response of just the basket treatment mod.
Samsung 60" UN60ES6100 LED Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga - LCR mids, inside* & out 8 ga Powerline: LR woofers, inside* & out *soldered LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & “Plugged*” Mids - 981, connected w/MP Premiere ICs Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s *Xschop's handy work -
I think THD measurements similar to what @DarqueKnight did with the tweeters in his epic thread "A Tale of 5 Tweeters" would probably show something beneficial.
@JayMX way to step up to the plate and those are great little bookies! Did you also do the section between the spokes/uprights, by the spider? I really think that's not to be neglected and is not an insignificant amount of surface area for reflection back at the cone.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 -
Look carefully at JayMX’s last pic - he did the spokes. He’ll hafta say how close he got to the spider.Gardenstater wrote: »@JayMX way to step up to the plate and those are great little bookies! Did you also do the section between the spokes/uprights, by the spider? I really think that's not to be neglected and is not an insignificant amount of surface area for reflection back at the cone.
@JayMX: you did use plain foam inside the frame. At least it looks that way from the pic.
Regardless ENJOY! Tony
Samsung 60" UN60ES6100 LED Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga - LCR mids, inside* & out 8 ga Powerline: LR woofers, inside* & out *soldered LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & “Plugged*” Mids - 981, connected w/MP Premiere ICs Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s *Xschop's handy work -
I'm talking about this area, in addition to the spokes:
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 -
Correct. I did not cover the rear perimeter/lip of the basket adjacent to the spider. I’ll do that on my 7B’s when the time comes.Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩
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Some “foaming” on the inside of an RTi A7 mid that Rob (xschop) just finished “pluggin’” recently. Look for it mounted on my Tri-amp ‘7 thread
Samsung 60" UN60ES6100 LED Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga - LCR mids, inside* & out 8 ga Powerline: LR woofers, inside* & out *soldered LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & “Plugged*” Mids - 981, connected w/MP Premiere ICs Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s *Xschop's handy work -
Here's a question:
Would foam be detrimental to a passive, because its sound generation is from the air behind the membrane- since it's not generated by the cone itself?
I'm 'matting the exterior of the baskets of mine (man, they're flimsy). I don't plan to foam them, but might 'matt the interior of the arms, just to add mass to dampen basket vibration even more.
Anyone played with this?
[in progress]
The Thrifty Setups in Mah House Big thrifty stereo in the basement w/ my custom SDA-1C (built with help from kind forum members) * Beautiful 1966 MCM GE console upgraded w/ Bluetooth, Dual turntable, and Paradigm speakers in family room * Swanky 1980 Realistic system and great TEAC eq with dancing colored lights in the living room * Ye Olde college stereo in the garage -
Really no need to do inside the basket. Most of us have all done the passive.
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Dyna-Mat/butyl matting the inner frame spokes would be ok.
My 5B PR baskets are inner-frame butyl matted. Foaming would be unnecessary as there are no midrange reflections to deal with from the passive. The passive is pneumatically decoupled from any midrange frequencies as well.
P.S. Post edited and spell-checked for F1's peace of mind.Post edited by xschop onDon't take experimental gene therapies from known eugenicists. -
A little Dynamat or the like goes a long way, there's absolutely no reason to cover every square inch and none should go inside the spokes.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
