Pair of SW-120 Passive Radiators

inspiredsports

I have an original matched pair of SW-120 Passive Radiators I purchased from a guy here in Ohio who was parting out a set of SDA-1B's. (I bought everything he had as the crossovers and MW-6509 drivers work in my SDA SRS 2's, but the passives do not).

These 12" SW-120 Passives were originally used in SDA-1, SDA-1A, SDA-1B, SDA-1C and SDA-2.

The Polk inspector handwritten dates on the backs of the passives are 3/24/87 and 3/25/87.

(They will work in an SDA-2A or SDA-2B in an emergency, but were NOT RECOMMENDED for these two models (the 2A and 2B use the SW-121 which is more flexible). The SW-120 has an extra layer of foam laminated to the surface making it stiffer, and it changes the bass characteristics if used in the wrong speaker. I experimented with these in my SDA-2B's just to see what would happen. The Bass was punchier, but not as deep (which makes sense as the SW-120 radiating surface is stiffer/less flexible due to the extra layer of material laminated onto it).

$35 each / $65 pair shipped US and paid via PayPal.

Note: the brown gasket on the backs (middle image) is brown Mortite.

nooshinjohn

in for the one shown on the left... My 1c's have a small weight attached to the center of the styrofoam... Is this correct for the 1c's or should I be replacing both of them?

inspiredsports

nooshinjohn wrote: »

in for the one shown on the left... My 1c's have a small weight attached to the center of the styrofoam... Is this correct for the 1c's or should I be replacing both of them?

I've done a lot of research on many of these speakers, but don't know the answer to that one. My GUESS is, that like so many Polk models, that there were small subtleties in the SW-120's used from year to year.

I can say that I do not believe anything has been removed from this particular pair. I believe they came from the factory the way they are with the exception of the Mortite I added in lieu of the foam gasket that did not separate well from the cabinet.

I'm not sure what you mean by weights. I've seen 15" passives with what appeared to be a half round dome of styrofoam attahced to the back center.

Maybe someone has a photo or knowledge about of what you are asking.

pmlewis

I think both may be correct. I bought a replacement some time ago that had no weight on the back, but the thicker disk on the front. The original had a lead weight on the back of the styrofoam and a thin disk on the front. Both are marked as SW-120, but if I remember correctly one was hand written on the basket and the other was a printed lablel. At the time I figured that the weight compensated for the difference in mass between the thin and thick disk. I always wanted to compare the weight of each to see if they matched but never got around to it. I will dig them out tonight when I get home and check them out.

inspiredsports

pmlewis wrote: »

I think both may be correct. I bought a replacement some time ago that had no weight on the back, but the thicker disk on the front. The original had a lead weight on the back of the styrofoam and a thin disk on the front. Both are marked as SW-120, but if I remember correctly one was hand written on the basket and the other was a printed lablel. At the time I figured that the weight compensated for the difference in mass between the thin and thick disk. I always wanted to compare the weight of each to see if they matched but never got around to it. I will dig them out tonight when I get home and check them out.

My guess is that both designs sound comparable, but would like to find out to make sure the style I have will work for John above before we complete the deal.

inspiredsports

nooshinjohn wrote: »

in for the one shown on the left... My 1c's have a small weight attached to the center of the styrofoam... Is this correct for the 1c's or should I be replacing both of them?

Are we still good for 1 or both?

I don't have an answer to the weight question, so I'm hoping for someone with more experience to chime in.

nooshinjohn

yes... I am still in, but would like to know about the weights.... I will call polk and see if they have info...

inspiredsports

nooshinjohn wrote: »

yes... I am still in, but would like to know about the weights.... I will call polk and see if they have info...

No worries. I'll hold both until you let me know either way.

Greg

nooshinjohn

inspiredsports wrote: »

No worries. I'll hold both until you let me know either way.

Greg

I will let you know by tonite

inspiredsports

nooshinjohn wrote: »

I will let you know by tonite

I've been away for a bit. Have you made a decision?

backsigns

Are these still available? If so, I'd be interested.

inspiredsports

Hello backsigns, and welcome to Club Polk!

Yes, they are still available. I know it has been a long time, but in fairness I would like to contact nooshinjohn (from post #9 above) as we never finished that discussion.

Also, it will be hard to communicate until you reach 25 post threshold and your forum messaging features become active.

backsigns

LOL Okay.

mmadden28

Actually you only need 10 posts for Private Messaging (PM) (25 to post a sale of your own)

inspiredsports

backsigns wrote: »

LOL Okay.

I'm not certain why you are laughing out loud. Nothing personal, I just want to be sure a member with 3,600+ posts here who expressed open interest does not need them.

inspiredsports

Lasareath wrote: »

I'd Laugh out loud too, after 6 months I wouldn't care if somebody said they wanted them and they had 20,000 posts!

Unless it was you and you found I'd sold them to a person with 1 post :D:D



PS: Good Luck next week, our prayers are with you.

backsigns

Sorry, I was just amused because it had been so long since you seem to have had anyone interested. I understand and appreciate your loyalty!

JayCee

Hi all. First, I'd like to apologize for this long post up front:o

I'm fairly new to CP but started my vintage Polk quest back in September. I posted for the first time when a pair of 2.3 TLs were available in Wa and asked bsoko2 for help securing them. I didn't realize bsoko2 was interested, so nooshinjohn politely pointed this out:) Here's what you wrote nj:

nooshinjohn: I believe he is interested in them for himself my friend... Welcome to CP. The slippery slope starts here.

I can't agree more...I'm experiencing the "slippery slope":D. I was very interested in the 2.3s bsoko2 sold last week but realized the shipping to Texas was not realistic. My ultimate goal is to find a pair of 1.2 TLs:D.

So, to the point of my post. In September I picked up a pair of very clean 2As and was very pleased. Two days ago I purchased a decent pair of 1Cs. After setting them up in my house I realized the passive radiator on one speaker was damaged:eek:. The front of the PR dipped in from the top. Not sure if it happened when I transported them or in my excitement at finding them, missed this obvious problem. I did not hear anything when I auditioned them.

I pulled the PR and found damage to the driver support fabric:

I pulled the other PR and it is perfect. My PRs have the weight on the back and are dated 9/22/87. The pictures above can now be used for comparison w/the version of PRs you have for sale. pmlewis wrote the following in a post above:

pmlewis: The original had a lead weight on the back of the styrofoam and a thin disk on the front. Both are marked as SW-120, but if I remember correctly one was hand written on the basket and the other was a printed lablel.

Inspiredsports, the dates on your PRs are 3/24 and 3/25/87. My guess is it's the opposite? The weights were added later? In either case, I need to fix or replace the PR. I have no clue how to restore the portion that disbonded/ripped from the back of the driver. Any suggestions? I'm also very interested in purchasing both PRs from inspiredsports if nooshinjohn and backsigns would allow me to. Obviously, I'd like to ensure both PRs are matched based on the physical characteristics.

In the interim, I installed an SW-121 from my 2As so I can play the 1Cs. I've not had more than an hour listening to them in the past 2 days, but they still sound good w/the mismatched PRs.

I realize I'm a very virgin CP newbie and don't have enough posts to PM, yet, but would really appreciate some the of the great CP karma. It's impossible to judge a person via a bulletin board post, but I am trustworthy and honest. For what it's worth, I'm in the Air Force and we live these values every day.

Again, thanks for reading this long post if you made this far. Any assistance is much appreciated.

John

JayCee

Jesse,

Thanks for the PM.

John