SDA CRS’s for Dummies

ThomasDThomasD Posts: 258
edited April 2 in Vintage Speakers
Just checking out a vinyl store in Anchorage for some new spins and noticed they’re playing the vinyl through some 12B’s. Talking to the owner I find out he’s got a couple other pairs of Polks, some 7’s & 10’s. Then he mentions he’s also got an old pair of CRS’s with the 2 tweeters. He wasn’t impressed with them, says even with the IC they didn’t sound right. He’s bringing them into the shop tomorrow for me to hear. I’m not versed on these CRS’s at all. Just know these must be one of the first 2 generations because of the dual SL1000/2000 tweets, & blade/blade IC. Any suggestions on what to look for and are they going to be worth $150 with a possible bad driver?
Thanks
Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
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Comments

  • boston1450boston1450 Posts: 6,516
    they are the less desirable crs. I myself have never heard the 2 tweet crs so i cqnt comment. 150 mint cause its gonna cost you for replacement. Take a listen u may like them
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
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  • boston1450boston1450 Posts: 6,516
    edited April 2
    Should be the SL2000 (not 100%sure)... While listening to them disconnect the IC cord & you should notice a change.... Ive hear of members disconnect the outter tweeter & supposedly it sounds much better. If you were to buy them it may be worth a try. You could also change out the tweeters to RD-0194 if the sl2000 & then have Xovers done later. Good Luck
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
    Dta100a MITcables.Dedicated 100w Grape Solar
    panel 2d/c batteries 400w inverter
  • ddogddog Posts: 213
    Nice...I'll be in Anchorage next week on vacation. I'm always looking for music/vinyl stores. Could I get the name of the store...

    I'm not looking to bring home any speakers...lol
  • Dr_WuDr_Wu Posts: 166
    I'm enjoying my original generation CRS speakers as I write. Bought new in 1984. They will sound terrific with the IC, and a few modifications. First, replace one of the tweeters with Polk's RD0194-1. Disconnect the dimensional tweeter (on the right side of the right channel; left of the left channel). Now, consider replacing the capacitors and resistors (plenty of threads here, if you do a search). While you're at it, do the modifications on the cabinets that are recommended in the SDA Handbook, available here.

    IMO, the finished product will out-perform bookshelves costing upwards of a grand. Just be sure to feed them enough power. 200wpc will do nicely.

    Offer 100 bucks in light of the possibly blown driver, and the fact you'll have to buy 2 new tweeters for a hundred bucks. Good luck!

  • ThomasDThomasD Posts: 258
    ddog wrote: »
    Nice...I'll be in Anchorage next week on vacation. I'm always looking for music/vinyl stores. Could I get the name of the store...

    I'm not looking to bring home any speakers...lol

    Obsession Records
    Little strip mall at the intersection of Lake Otis & Tudor
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • ThomasDThomasD Posts: 258
    @Dr_Wu Are you saying to disconnect the SDA altogether?
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • ThomasDThomasD Posts: 258
    boston1450 wrote: »
    they are the less desirable crs. I myself have never heard the 2 tweet crs so i cqnt comment. 150 mint cause its gonna cost you for replacement. Take a listen u may like them

    Have my SDA 2a’s x/o’s being done by @westmassguy currently. Like that these are real wood veneered. Not sure on SQ of these generation’s.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • boston1450boston1450 Posts: 6,516
    ThomasD wrote: »
    @Dr_Wu Are you saying to disconnect the SDA altogether?

    No. Just the outter dimentional tweeter on each cabinet
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
    Dta100a MITcables.Dedicated 100w Grape Solar
    panel 2d/c batteries 400w inverter
  • ThomasDThomasD Posts: 258
    And by the way, where is the SDA Handbook located on this forum? I’ve looked before and only found it referrenced to but not listed. It’s probably staring me in the face here somewhere but I’m too blind to see it.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • boston1450boston1450 Posts: 6,516
    Dr_Wu wrote: »
    I'm enjoying my original generation CRS speakers as I write. Bought new in 1984. They will sound terrific with the IC, and a few modifications. First, replace one of the tweeters with Polk's RD0194-1. Disconnect the dimensional tweeter (on the right side of the right channel; left of the left channel). Now, consider replacing the capacitors and resistors (plenty of threads here, if you do a search). While you're at it, do the modifications on the cabinets that are recommended in the SDA Handbook, available here.

    IMO, the finished product will out-perform bookshelves costing upwards of a grand. Just be sure to feed them enough power. 200wpc will do nicely.

    Offer 100 bucks in light of the possibly blown driver, and the fact you'll have to buy 2 new tweeters for a hundred bucks. Good luck!

    Question. Can those be TL'd while at it ? So you can use the RD-0198 tweeter. Just wondering as i dont know much about 1st generation Crs speakers upgrade
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
    Dta100a MITcables.Dedicated 100w Grape Solar
    panel 2d/c batteries 400w inverter
  • ThomasDThomasD Posts: 258
    boston1450 wrote: »
    ThomasD wrote: »
    @Dr_Wu Are you saying to disconnect the SDA altogether?

    No. Just the outter dimentional tweeter on each cabinet

    Please pardon my ignorance. So are both tweets dimensional and you disconnect one on each channel or by disconnecting one tweet does it leave just the mid-woofer as dimensional?
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • boston1450boston1450 Posts: 6,516
    Left speaker Left tweeter----Right speaker Right tweeter... You can disconnect them so no cross talk from 2 tweeters on R & L speaker cabinets... The outter driver is dimentional driver. As long as you use your IC cord your SDA. Hope i said it right
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
    Dta100a MITcables.Dedicated 100w Grape Solar
    panel 2d/c batteries 400w inverter
  • ThomasDThomasD Posts: 258
    boston1450 wrote: »
    Left speaker Left tweeter----Right speaker Right tweeter... You can disconnect them so no cross talk from 2 tweeters on R & L speaker cabinets... The outter driver is dimentional driver. As long as you use your IC cord your SDA. Hope i said it right

    Does that just leave 1 mid-woofer in each channel as dimensional an the tweets as strictly stereo?
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • boston1450boston1450 Posts: 6,516
    edited April 2
    @Dr_wu might know. Im not 100% sure. But if you dont use your IC cord one of the tweeters might not work & also a driver too. I might be wrong here. Cant Remember Shat
    ...
    ...
    Randy / Maine
    SDA-CRS+ 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Stands w/Polk Logo & Spiked nicely
    RTA15TL 198 tweeters. WMG upgraded crossovers.
    Larry's rings. Gloss tops shine. Spiked nicely
    Cs1000p-Yamaha-Parasound-Acurus
    MIT speaker cables-Pangea powercords
    Camp: Klipsch Heresy ii's Dayton Audio
    Dta100a MITcables.Dedicated 100w Grape Solar
    panel 2d/c batteries 400w inverter
  • ThomasDThomasD Posts: 258
    monepolk wrote: »

    Thank you. I’ve been to that post a dozen times but on my Iphone it doesn’t show any actual link. @VR3 link works.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • ThomasDThomasD Posts: 258




    Question. Can those be TL'd while at it ? So you can use the RD-0198 tweeter. Just wondering as i dont know much about 1st generation Crs speakers upgrade


    A very good question indeed. Was going to ask @westmassguy if no one else responds.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • F1nutF1nut Posts: 43,111
    You cannot TL the original CRS.

    Disconnecting the SDA cable will result in the SDA tweeters not working and the SDA drivers only producing sound below 150Hz....maybe 100Hz, can't remember.
    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

  • ThomasDThomasD Posts: 258
    @F1nut I Understand about the IC. But what is the purpose of disconnecting the SDA tweeter as recommended above ?
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • F1nutF1nut Posts: 43,111
    Ok, if you disconnect the SDA tweeter the SDA driver still plays. I recommend doing that as the SDA tweeter makes things sound a bit too phasey.
    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

  • ThomasDThomasD Posts: 258
    Thanks F1. As @boston1450 said It sounds like these gen CRS’s are not the preferred model. Can RD-0194’s be used as replacements for either SL1000’s or 2000’s? Won’t know which they are until I physically see them.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • F1nutF1nut Posts: 43,111
    They should have SL2000's, so you can use the RD0194.
    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

  • pitdogg2pitdogg2 Posts: 14,909
    ThomasD wrote: »
    Thanks F1. As @boston1450 said It sounds like these gen CRS’s are not the preferred model. Can RD-0194’s be used as replacements for either SL1000’s or 2000’s? Won’t know which they are until I physically see them.

    Yes you can use the RD-0194 for replacement to both of those tweeters BUT the SL1000 has a differrent cut out and modifications to the holes will be needed. Although less desirable they are close and if price is right worth it as they do have a very good soundstage.
  • ThomasDThomasD Posts: 258
    Thought Id read that the first series CRS had SL1000’s. Maybe I am remembering wrong.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • Dr_WuDr_Wu Posts: 166
    @ThomasD,

    Sorry I had to log off earlier, but I'll try to help. Hope I've got this right. From what I understand from the great folks here, especially westmassguy, F1nut, VR3 and DarkeKnight, there were 2 generations of CRS with 2 tweeters and blade/blade ICs. The earliest of these had SL1000 tweeters, the latter had SL2000. Both can be replaced by the RD0194-1. They sound very good, too. These models have different crossovers than the later, CRS+ models. The CRS+ are more desirable because they can be TLd, and can also be equipped with a Dreadnaught for more amp variations, including non-common ground and mono blocks.

    Each speaker has a dimensional tweeter and mid-woofer, and a stereo tweeter and mid-woofer. You will still get the full SDA sound stage with the stereo tweeter and both mid-woofers.

    Disconnecting the dimensional (outside) tweeter in each cabinet is a breeze. If you have a version with fuses on the connector pan, just pull the one marked dimensional. If there are no fuses, remove the dimensional tweeter from the front baffle and disconnect the wires from the terminals.

    Yes, the RD0194-1 is a little larger than the recesses in the black fascia on the baffle. Your choices are to do a little woodworking to enlarge them, or cut the outer rim/flange off the RD0194 (a Dremel cutting wheel works well). Make sure you leave as much plastic around the mounting holes as possible. Buff the edges smooth. They'll now fit in the original cut-outs and mount flush to the baffle.

    To make going into and out of the cabinets easy and without the risk of stripping screws, fit the holes with hurricane nuts and buy 8-32 machine screws to replace the originals. If you're very lucky you might find a set of Larry's Rings which eliminate the need for hurricane nuts and to which the mounting screws attach.

    New caps: most often recommended are Sonicap Gen I or Clarity Caps. Resistors: Mills/Vishay Mills 12, Duelund, Munndorf seem to be the preferred brands. If there are polyswitch/safeties, replace them with a jumper or .5 ohm resistor. They can degrade SQ. The tweeter may sound brighter to you without a resistor (or you might prefer it that way). Internal wiring can be replaced, if you want. Connectors, too. Gimpod's larger boards for mounting the components are not available for the early CRS models.

    Inside the cabinets, seal the seams, glue the magnets on the drivers, Dynamat the driver housings, replace gaskets as needed, consider adding dampening material.

    You can also have a beefier IC cable made, and equipped with Neutrik Speakon connectors. High quality 5-way binding posts are also recommended.

    There are CRS upgrade threads galore here, many with great pics and how-to tips. And, I haven't found anyone here who has done these upgrades who isn't generous with advice. Hope this helps.
  • ThomasDThomasD Posts: 258
    edited April 2
    @Dr_Wu Thanks for the response. That pretty much explains what I was wondering. As far as the physical upgrades/mods, they are no problem as I've done them all for my 7c's & SDA 2a's (except for the elusive Larry's Rings). Don't consider myself very adept @ the x/o's so will probably send them out for updating, assuming the speakers are in decent shape and we agree on a price.
    Now, just to absolutely be clear, I seem to remember reading somewhere on this forum (unable to find the thread right now) that replacing the SL-1000's with RD-0194's in the early CRS's required some type of x/o mod (along with the physical mounting plate mod), resistor change, removal or something. Sorry, don't mean to be difficult but want to get all the information I can to at least seem somewhat intelligent on this purchase.
    Sincerely appreciate all the knowledgeable input here.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • Dr_WuDr_Wu Posts: 166
    ThomasD, I replaced SL1000 tweeters with RD0194s. No change in the crossovers was required, except that the 750pF silver mica bypass cap on each tweeter circuit should be eliminated. The newer tweeters make them unnecessary. You also need to be careful about resistor values depending on whether your set has fuses or polyswitches. The revisions from the earliest generation to the next are noted on the schematic.

    https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26679.pdf
  • ThomasDThomasD Posts: 258
    @Dr_Wu Perfect. Thank you
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
  • F1nutF1nut Posts: 43,111
    It's not the new tweeters that make the polyswitch unnecessary. It's when the crossovers get upgraded with film caps.
    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

  • ThomasDThomasD Posts: 258
    edited April 3
    F1nut wrote: »
    It's not the new tweeters that make the polyswitch unnecessary. It's when the crossovers get upgraded with film caps.

    So, I can safely just swap out the SL1000/2000 with the RD-0194's and do nothing else to the x/o's ?
    Edited
    Been reading the SDA Handbook and believe the answer to my question is 'yes'.
    Carver M4.0t, M1.0t, M200t, TX2, C1, C2, Marantz 2230, 2010, Rega Brio, Marantz Imperial 7's, Klipsch Heresy III, Quartets, KG4's, KG1's, 'The Sixes', R-12SW, Polk SDA 2a's, Monitor 7cTL's, SDA CRS's, 4a's, Zu Audio Dirty Weekends, Pro-ject Acryl TT, Cambridge 851N, 351C, Panamax 5300PM
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