RTA12B information

WWA
WWA Posts: 32
in Vintage Speakers
002_zpsa320f4f6.jpg~original

003_zps236f9024.jpg~original

001_zpsacaab4bf.jpg~original




Picked up a set and there seems to be very little info out there on these , I think they are early B's , they have MW6600x drivers and a fuse for the tweeters , would like to know the ohm rating and any other info will be appreciated .





· Share on FacebookShare on Twitter

Comments

  • Nightfall
    Nightfall Posts: 10,086
    edited October 2014
    4 ohms, 500 watts, peerless tweeters, mirror imaged (right speaker has to be on right, left on left), outside and inside midwoofers are crossed over at different frequencies. Haven't been able to find their sensitivity @ 1 watt. Some say 88-89db some say 90-91db.
    afterburnt wrote: »
    They didn't speak a word of English, they were from South Carolina.

    Village Idiot of Club Polk
    · Share on FacebookShare on Twitter
  • drumminman
    drumminman Posts: 3,396
    edited October 2014
    Here's the schematic. It's listed as RTA 12B, but it's the same for the 12C: https://us.v-cdn.net/5021930/uploads/attachments/4/6/7/2/8/18712.pdf

    There are lots of schematics archived in sticky's at the top of this page.
    "Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer
    · Share on FacebookShare on Twitter
  • boston1450
    boston1450 Posts: 7,639
    Those are beautiful. Did you get the HATS (tweet covers) too. They are power hungry speakers & what I've heard is a great speaker. Welcome to Club Polk
    ..
    · Share on FacebookShare on Twitter
  • drumminman
    drumminman Posts: 3,396
    They are indeed great speakers, with imaging that approaches SDA. Well worth modding if you plan on keeping them.
    "Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer
    · Share on FacebookShare on Twitter
  • Mr. Bubbles
    Mr. Bubbles Posts: 736
    I love my RTA 12's probably second favorite speaker to my 2A's of all my vintage Polk.
    If con is the opposite of pro, is Congress the opposite of Progress?!


    Monitor 5Jr, Monitor 5, RTA12, RTA 15TL, SDA 2A, 1c, SRS 2, 1.2TL, CRS, Atrium.
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    Thanks for the welcome and the link and the info , I have been on the AK forum for a couple of years and just joined here . I do have the hats and grills , need to clean the tops they are a little dirty . I have some SDA1B's powered by a Kenwood M2 ,they sound great and am looking forward to listening to these when I get the driver replaced , I hope my Marantz 2330B will make these sound nice .
    · Share on FacebookShare on Twitter
  • Faustin
    Faustin Posts: 1,149
    Welcome to CP. I have a pair of 12c's that have been rebuilt and modded. I re-veneered them over the summer in a curly grained cherry. My tophat covers were quite dirty as well. I removed them from the frames and hand washed them in Woolite and let them air dry. They came out great. I have run mine with a Yamaha CR 2020 and they do well. I would think your 2330B will sound great with the 12's. Drivers should be MW 6501's if I am not mistaken.
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    Thanks for the welcome Faustin , the drivers in these are mw6600x , looks like it may be harder to find than the 6501 .
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    Hopefully I can get the covers clean without taking them apart , lots of staples to pull out .
    · Share on FacebookShare on Twitter
  • Faustin
    Faustin Posts: 1,149
    Are all of the drivers mw6600's? Also, my top hats did not have staples holding them on to the frames. A rubber spline such as you would use to hold a screen in a frame for a window is used in a groove around the frame.
    · Share on FacebookShare on Twitter
  • drumminman
    drumminman Posts: 3,396
    Faustin wrote: »
    Are all of the drivers mw6600's? Also, my top hats did not have staples holding them on to the frames. A rubber spline such as you would use to hold a screen in a frame for a window is used in a groove around the frame.

    Mine are the same - WWA has an earlier version. I would be hesitant to take the covers off as they would be a **** to reinstall.
    "Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer
    · Share on FacebookShare on Twitter
  • westmassguy
    westmassguy Posts: 6,850
    Welcome to CP!
    mglhc83x41pq.jpg
    t9xyo4i030aq.jpg
    This was copied from a 1982 Stereo Review Article:
    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/
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    I have only pulled the one driver that is bad to get the number , have not looked at the rest . I agree about the covers they are stretched tight . I have cleaned several sets of grills with soap and water and am going to do that this weekend , plus give the speakers a general clean up .
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    Thank you for posting the review .
    · Share on FacebookShare on Twitter
  • soundfreak1
    soundfreak1 Posts: 3,414
    Very nice speakers. They will "work" on the marantz, however they need real power to reach thier full potential. 200 watts is a nice starting place. Ad stated before make sure they are in the "left/right" positions! They should be marked Land R somewhere. Enjoy them properly powered they are quite surprising speakers.
    Main Rig:
    Krell KAV 250a biamped to mid/highs
    Parasound HCA1500A biamped to lows
    Nakamichi EC100 Active xover
    MIT exp 1 ic's
    Perreaux SA33 class A preamp
    AQ kingcobra ic's
    OPPO 83 CDP
    Lehmann audio black cube SE phono pre, Audioquest phono wire (ITA1/1)
    Denon DP-1200 TT. AToc9ML MC cart.
    Monster HTS 3600 power conditioner
    ADS L1590/2 Biamped
    MIT exps2 speaker cable
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    Sounds like they are similar to SDA's , at least for power requirements . When I got my SDA speakers I had members on AK tell me to get a 200 wpc amp for them also , I hope that the RTA's will not dip to 2 ohm like the 1b's .
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    And yes they are marked left and right .
    · Share on FacebookShare on Twitter
  • soundfreak1
    soundfreak1 Posts: 3,414
    As far as going to 2 ohm ,not sure but wouldn't surprise me. Pick up something like a vintage Parasound HCA 1200 plays the 12b's very nicely and can handle any thing you can through at it cost ya around 3/4 hundo and well worth it.used it with mine and it was fantastic.
    Main Rig:
    Krell KAV 250a biamped to mid/highs
    Parasound HCA1500A biamped to lows
    Nakamichi EC100 Active xover
    MIT exp 1 ic's
    Perreaux SA33 class A preamp
    AQ kingcobra ic's
    OPPO 83 CDP
    Lehmann audio black cube SE phono pre, Audioquest phono wire (ITA1/1)
    Denon DP-1200 TT. AToc9ML MC cart.
    Monster HTS 3600 power conditioner
    ADS L1590/2 Biamped
    MIT exps2 speaker cable
    · Share on FacebookShare on Twitter
  • westmassguy
    westmassguy Posts: 6,850
    From the same review I posted, the lowest measured impedance was 3 ohms between 100 and 1500Hz. A quality amp that is rated for 4ohm loads will work fine.
    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/
    · Share on FacebookShare on Twitter
  • drumminman
    drumminman Posts: 3,396
    Re: setting up properly, mine were in storage for many years. When I pulled them out and set them up I had them reversed, i.e. left speaker on right, etc. Was easy to hear that something was wrong - no soundstage at all.
    "Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer
    · Share on FacebookShare on Twitter
  • WWA
    WWA Posts: 32
    I have been thinking about a Parasound for the SDA's , so if I get one at a later date I can use the Kenwood on the RTA's , but for now when I get the 12's fixed I am going to use the Marantz for a little while , it has been recapped so as long as I don't push it to hard it should be ok with the RTA's .
    · Share on FacebookShare on Twitter
  • soundfreak1
    soundfreak1 Posts: 3,414
    drumminman wrote: »
    Re: setting up properly, mine were in storage for many years. When I pulled them out and set them up I had them reversed, i.e. left speaker on right, etc. Was easy to hear that something was wrong - no soundstage at all.

    LOL did the same thing when I first got the 12b's, didn't know they were L/R sounded awful. Than by accident switched them around and WOW .

    Main Rig:
    Krell KAV 250a biamped to mid/highs
    Parasound HCA1500A biamped to lows
    Nakamichi EC100 Active xover
    MIT exp 1 ic's
    Perreaux SA33 class A preamp
    AQ kingcobra ic's
    OPPO 83 CDP
    Lehmann audio black cube SE phono pre, Audioquest phono wire (ITA1/1)
    Denon DP-1200 TT. AToc9ML MC cart.
    Monster HTS 3600 power conditioner
    ADS L1590/2 Biamped
    MIT exps2 speaker cable
    · Share on FacebookShare on Twitter