RTA 12b SDA?

Options
FestYboy
FestYboy Posts: 3,861
in Vintage Speakers
Tried searching before posting this potentially dumb question, but has there ever been an attempt to SDA mod a pair of 12Bs? I've seen 10s go under the knife, and I'd assume 11s would take to it just as well seeing as they are so similar. But I'm more curious about the RTAs.
· Share on FacebookShare on Twitter

Comments

  • xschop
    xschop Posts: 4,684
    Options
    Throw in a set of CRS crossovers. Im running a mw6503 (higher ohm) as the dimensional driver and the SDA "effect" is all there.
    Don't take experimental gene therapies from known eugenicists.
    · Share on FacebookShare on Twitter
  • FestYboy
    FestYboy Posts: 3,861
    Options
    Changing the load changes the XO perameters... But the thought did cross my mind.
    · Share on FacebookShare on Twitter
  • xschop
    xschop Posts: 4,684
    Options
    Yes, but the dimensional driver will have lower excursion and to me, the mids cleared up a bit at higher volume.
    Don't take experimental gene therapies from known eugenicists.
    · Share on FacebookShare on Twitter
  • FestYboy
    FestYboy Posts: 3,861
    Options
    ^ and this is in on RTAs? Got any pics?
    · Share on FacebookShare on Twitter
  • xschop
    xschop Posts: 4,684
    Options
    No, I did this on my CRS. My point was you might like what you hear.
    Don't take experimental gene therapies from known eugenicists.
    · Share on FacebookShare on Twitter
  • FestYboy
    FestYboy Posts: 3,861
    Options
    Ah thanks for the clarification. I'll keep it in mind if I try it.
    · Share on FacebookShare on Twitter
  • voltz
    voltz Posts: 5,384
    Options
    Hey Arty

    I did it to my 10's and like the results as did Ronnie!

    I recently found a set of SDA 2B's which use the same crossovers as my CRS+'s with the TL mod. I already put hurricane **** on them added blackhole hole 5 on back wall in 3x12 strips starting at the bottom of drivers and going up towards top of cabinet.

    So i pulled my crossover from my CRS's and stuck them in it an the binding post cup so I could use my Dreadnaught Brother Dave made me and the RDO -198 tweeters instant up grade LOL :p

    I don't have a house to take advantage of the SDA 2B's close to the wall so the CRS which play better slightly out in the room more fits me better. but after rearranging furniture and doing what I could i was able to ROCK-T-House!!!
    a buddy at work made me swear a oath the if i sell the 2B's he gets 1st dib's :smiley:

    So if I had some RTA12's (as my buddy does that wants the 2B's when I explained to him they were like his RTA12's which a extra kick called SDA he then made me promise to remember him :) I would try it

    yes it can be a pain trying to find a place to mount the crossovers and such but it is worth a listen if you ask me! better then a Feista going down a really big hill ;)
    2 ch- Polk CRS+ * Vincent SA-31MK Preamp * Vincent Sp-331 Amp * Marantz SA8005 SACD * Project Xperience Classic TT * Sumiko Blue Point #2 MC cartridge

    HT - Polk 703's * NAD T-758 * Adcom 5503 * Oppo 103 * Samsung 60" series 8 LCD
    · Share on FacebookShare on Twitter
  • Schurkey
    Schurkey Posts: 2,100
    Options
    voltz wrote: »
    hurricane ****
    Someone at Vanilla needs their teslacles squidged.

    Ken? You there? Can you fix this?
    · Share on FacebookShare on Twitter
  • Viking64
    Viking64 Posts: 6,679
    Options
    knuts? ****? nuhts?
    · Share on FacebookShare on Twitter
  • westmassguy
    westmassguy Posts: 6,850
    Options
    FestYboy wrote: »
    Tried searching before posting this potentially dumb question, but has there ever been an attempt to SDA mod a pair of 12Bs? I've seen 10s go under the knife, and I'd assume 11s would take to it just as well seeing as they are so similar. But I'm more curious about the RTAs.

    Tinkering with a pair of Monitor 10s is one thing (I've done it). They're a dime a dozen relatively speaking. RTA-12s are a whole different animal. They are arguably the most accurate, "audiophile" stereo speaker Polk made back then. They were Polk's TOTL stereo pair. I personally would never dream of "Franken-Polking " them.

    If you own a pair, they're yours to do with as you please.
    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
  • FestYboy
    FestYboy Posts: 3,861
    edited September 2017
    Options
    @westmassguy
    Dave, the only reason I'm even considering it is the fact that I have spare parts AND if I do it right, it would be completely reverseable without damaging the originality of the RTAs. To that, you bring up the one point as to where this hair brained idea came from: they're super accurate. I think if I had a pair of SDA 2s, I'd mod them with RTA components first instead, but I haven't found a pair in a price range I'm willing to pay, yet.
    · Share on FacebookShare on Twitter
  • pitdogg2
    pitdogg2 Posts: 24,559
    Options
    SDA 2 is not time aligned like RTA is.
    If that makes a difference
    · Share on FacebookShare on Twitter
  • westmassguy
    westmassguy Posts: 6,850
    Options
    FestYboy wrote: »
    @westmassguy
    Dave, the only reason I'm even considering it is the fact that I have spare parts AND if I do it right, it would be completely reverseable without damaging the originality of the RTAs. To that, you bring up the one point as to where this hair brained idea came from: they're super accurate. I think if I had a pair of SDA 2s, I'd mod them with RTA components first instead, but I haven't found a pair in a price range I'm willing to pay, yet.

    Like I said, if you have a pair, they're yours to do with as you please. No harm, no foul. There's no Polk police that will break down your door, and take them from you.
    Keep in mind, the setback for the tweeter/crossover assembly was done for a reason, time alignment, and the inner and outer woofers on the B & C revision, receive different signals. The original RTA-12 is smaller, and doesn't have the woofer signal modifications.
    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
  • FestYboy
    FestYboy Posts: 3,861
    Options
    pitdogg2 wrote: »
    SDA 2 is not time aligned like RTA is.
    If that makes a difference

    Right. In my head, I'd remove the tweet from the enclosure and mount it ala the RTA... I imagine it would be easier to do that than mod the 12s, but I don't have a pair of those, yet... ;)
    · Share on FacebookShare on Twitter
  • xschop
    xschop Posts: 4,684
    Options
    The RTA-12 would allow you to experiment with tweeter position easily once you grafted in the SDA crossover. I prefer the tweet as close to stereo driver as possible.
    Don't take experimental gene therapies from known eugenicists.
    · Share on FacebookShare on Twitter
  • FestYboy
    FestYboy Posts: 3,861
    Options
    As do I, and in our case, a semi horn loaded tweeter would solve alot of issues in that respect. And if you really wanted to keep things in line, an X configuration (4 MW and a semi horn loaded tweeter in the center) would be rather effective. It would act much like a single point system.
    · Share on FacebookShare on Twitter
  • voltz
    voltz Posts: 5,384
    Options
    Also when I did it to my 10's it was easy to put them in and take them back out and I did not harm them and/or the crossovers.
    2 ch- Polk CRS+ * Vincent SA-31MK Preamp * Vincent Sp-331 Amp * Marantz SA8005 SACD * Project Xperience Classic TT * Sumiko Blue Point #2 MC cartridge

    HT - Polk 703's * NAD T-758 * Adcom 5503 * Oppo 103 * Samsung 60" series 8 LCD
    · Share on FacebookShare on Twitter
  • JayMX
    JayMX Posts: 435
    Options
    Funny, I had the same thoughts about my 12C's... if you do it I'm interested inhearing about the results!
    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 🤩
    Pairs that have passed through: Monitor 4b (Peerless), Monitor 5a (Peerless), Monitor 5b (SL1000), Monitor 5b (SL2000) (3x pair), Monitor 7b (Peerless), Modified Monitor 7c’s (194’s), Monitor 10a (Peerless), Monitor 10b (5x pair), RTA8, RTA8TL, RTA 11T, RTA12c (194's), SDA CRS, SDA 2 (2x pair), SDA 2a, SDA 2b, SDA 1b, SDA 1c, SDA SRS 2 (2x pair), SDA SRS 3.1TL (198’s) (2x pair)...and more to come, it’s a sickness.
    · Share on FacebookShare on Twitter
  • TNTsTunes
    TNTsTunes Posts: 751
    Options
    If you were going to try this I suggest using the low pass crossover layout from a 2b and the matching 6503 and 6511 drivers they use in combination with the stock high pass from the RTA12B's. Who knows? It might just sound great.
    "Make a man a fire and he'll be warm for a day. Light
    a man on fire and he'll be warm for the rest of his life."

    · Share on FacebookShare on Twitter