Polk 7A midwoofer question

Greetings, new member here. Apologies for being long winded a bit here...

I just bought a pair of 7A's, serial numbers are 03049 and 03093 so pretty low I think. The mids have the Masonite rings on them but when I pulled them out to see what version there was no identifying marks/labels on the back. One did have "SKU 132" and "557" and "708" written on them in marker.

I noticed after I had them all hooked up that one of the mw's has a clean rip/tear in the rubber surround. Temporarily I've brushed some super glue over it, which seems to be working fine.

Anyway, what is the recommended replacement mid-woofer for 7A? I didn't remove the wires from the mid when I had it out (they're soldered on) but when I check resistance from the speaker wire plugs, the entire speaker measures 7.5 - 7.7 range.

All I am thinking is I need to stay away from the 6502s because they were 4 ohm. 6500's or 6503 is what I'm thinking from reading here.

Do the Masonite rings really do anything? Could it be moved to a new mid if I get one that doesn't have it? I get kind of anal about things like this, and if they didn't match on both speakers I would obsess on it....

Also, I was thinking I would replace the caps on the crossovers, but they sound so good right now I'm afraid to mess with them. (I have a pair of Elac B6 bookshelf speakers also hooked up and switch between the two, so that's all I have right now to compare.)

On a side note, years ago I had some black SDA 2B Studios and got rid of them like a fool - wife didn't like seeing big speakers. Just like I got rid of all my albums for CDs, which I'm buying them all back on vinyl now....I'm back looking at vintage Polk. Love them.

Thanks for any insight.

Comments

  • pitdogg2
    pitdogg2 Posts: 25,438
    edited May 2018
    Mw6502 is the correct driver for all models from what i see.
    They are plentiful you should not have any problem acquiring them.
  • westmassguy
    westmassguy Posts: 6,850
    edited May 2018
    Early Monitor 7s and 5s had MW6500s. The ring on the front is a fiber gasket, not Masonite. It serves no purpose for front mounted woofers.
    Home Theater/2 Channel:
    Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
    Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
    Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
    Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
    Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer

    dhsspeakerservice.com/
  • tjw141
    tjw141 Posts: 9
    Thanks, didn't think that ring/gasket did anything but wasn't sure.
  • @westmassguy - I have Polk 7B's, serial 197xx. Would this be the MW6502 or the MW6500? I may need to replace one of them that has been *chuffing* a bit every once in a while, on challenging music. Thanks.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    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
  • F1nut
    F1nut Posts: 50,542
    Take the driver out, the model is printed on the rear of the driver.
    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

  • Thanks. It's the silver frame MW6500 manufactured 1979. Bought a black frame NOS Polk OEM MW6500 on eBay since there are only used silver frame one's apparently, although if I ever find a NOS one I will snatch that up.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    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