SDA1b (or early c) - opinions?

JayMXJayMX Posts: 124
edited October 20 in Vintage Speakers
Picking these up tomorrow for a song. No interconnect, but can build one. Opinions? Suggestions? Thoughts? Where do these fall on the ol Polk desirability scale?
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Upstairs 5.1.2:
Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

Downstairs 7.2.4:
Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

Office:
Cambridge Soundworks Amp
Monitor 4b (Peerless)

Spares:
Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

Repair pile: SDA2, SDA1b
...and more to come, it’s a sickness.

Comments

  • JayMXJayMX Posts: 124
    What are the differences between the 1B’s & early 1C’s other than driver loading?
    u3pcd5knzkc6.jpeg
    Upstairs 5.1.2:
    Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

    Downstairs 7.2.4:
    Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

    2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

    Office:
    Cambridge Soundworks Amp
    Monitor 4b (Peerless)

    Spares:
    Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

    Repair pile: SDA2, SDA1b
    ...and more to come, it’s a sickness.
  • mlistens03mlistens03 Posts: 2,244
    Looks like the SDA 1C uses the MW6511 for stereo drivers and 6510 for dimensional, 1B seems to use MW6509 for both. I’d guess one is easier to driver, or something.
    Value wise? No clue.
    Micah

    Main system: Technics SL3200, Shure M97xE, Lafayette LR1100 for tuner, Hagerman Audio Labs Bugle 2 phono stage, NAD C352 integrated, Boston Acoustics VR 2, Boston PV500, generic ICs, and BJC Belden speaker cables.

    Desktop: Dell Precision 690 running iTunes, Yamaha RX-v665, Monitor Audio R90s, Velodyne VA-907, generic ICs and speaker cables.
    I've always thought the goal of high-end audio was not to have your neighbors bang on the wall and say, 'Turn that darn music down' but to have your neighbors bang on the wall and say, 'Tell your friends to go home and you can practice later this week'.
  • westmassguywestmassguy Posts: 6,154
    Completely different generations. The 1B is 3rd, 1C is 4th. 1C is more desirable, and relatively easier to drive. 1B is 4 ohm, 1C 6 ohm nominal.
    Some early 1Cs used leftover circuit boards from the 1Bs.
    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
    Cables: Speaker: Furez 10/2 with GLS Locking Banana Plugs
    Interconnect: Furez 10/2 with SpeakONs
    ICs: Custom Furez by Douglas Connections
    Den:
    Bose 901 Series II Continentals Restored, Re-Built Equalizer with Elna Silmic IIs, Sonicaps, and Silver Mica Caps
    Carver CT-3 Pre, Carver C-500

    dhsspeakerservice.com/
    Exclusive Distributor of Gimpod's Custom SDA Circuit Boards

    "And keep her under 70, would you, huh? Betty likes a slow ride"
  • mlistens03mlistens03 Posts: 2,244
    JayMX wrote: »
    What are the differences between the 1B’s & early 1C’s other than driver loading?

    🤦🏻‍♂️Missed that, sorry.
    Micah

    Main system: Technics SL3200, Shure M97xE, Lafayette LR1100 for tuner, Hagerman Audio Labs Bugle 2 phono stage, NAD C352 integrated, Boston Acoustics VR 2, Boston PV500, generic ICs, and BJC Belden speaker cables.

    Desktop: Dell Precision 690 running iTunes, Yamaha RX-v665, Monitor Audio R90s, Velodyne VA-907, generic ICs and speaker cables.
    I've always thought the goal of high-end audio was not to have your neighbors bang on the wall and say, 'Turn that darn music down' but to have your neighbors bang on the wall and say, 'Tell your friends to go home and you can practice later this week'.
  • JayMXJayMX Posts: 124
    edited October 20
    Completely different generations. The 1B is 3rd, 1C is 4th. 1C is more desirable,....

    Some early 1Cs used leftover circuit boards from the 1Bs.

    So they may be C’s even if they are blade/blade... if are loaded with 6510’s & 11’s they should be usable with isolation transformer/mono blocks? Correct?
    Upstairs 5.1.2:
    Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

    Downstairs 7.2.4:
    Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

    2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

    Office:
    Cambridge Soundworks Amp
    Monitor 4b (Peerless)

    Spares:
    Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

    Repair pile: SDA2, SDA1b
    ...and more to come, it’s a sickness.
  • Dennis GardnerDennis Gardner Posts: 4,758
    edited October 20
    Those serial numbers indicate that they can't be used with monoblocks.

    https://us.v-cdn.net/5021930/uploads/attachments/6/4/8/2/8/9806.jpg
    HT Optoma HD25 LV on 80" DIY Screen, Anthem MRX 300 Receiver, Pioneer Elite BDP 51FD Polk CS350LS, Polk SDA1C, Polk FX300, Polk RT55, Dual EBS Adire Shiva 320watt tuned to 17hz, ICs-DIY Twisted Prs, Speaker-Raymond Cable

    2 Channel Thorens TD 318 Grado ZF1, SACD/CD Marantz 8260, Soundstream/Krell DAC1, Audio Mirror PP1, Odyssey Stratos, ADS L-1290, ICs-DIY Twisted , Speaker-Raymond Cable
  • MalbecMalbec Posts: 469
    These don't appear to be compatible with the isolation transformer.

    NOTE: Some early units of SDA-1C and all units of SDA-2B require plug adapters and some internal modifications to the crossover to be used with the Non-Common Ground Amplifier Interface. The affected SDA-1C units can be identified by serial number as follows:
    Right Channel #6001 through 6310 and #6501 through 6678 Left Channel #5975 through 6370 and #6532 through 6656

    If the serial numbers of your speakers fall within these limits, please contact Polk Audio for modification details.
  • JayMXJayMX Posts: 124
    perfect. This helps me with determining what to offer the guy selling. The cabinets look rough, hoping to get them for less than a Benjamin! We will see what this afternoon holds. Thanks all.
    Upstairs 5.1.2:
    Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

    Downstairs 7.2.4:
    Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

    2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

    Office:
    Cambridge Soundworks Amp
    Monitor 4b (Peerless)

    Spares:
    Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

    Repair pile: SDA2, SDA1b
    ...and more to come, it’s a sickness.
  • la2vegasla2vegas Posts: 2,887
    JayMX wrote: »
    perfect. This helps me with determining what to offer the guy selling. The cabinets look rough, hoping to get them for less than a Benjamin! We will see what this afternoon holds. Thanks all.

    I thought you said all you had to do to get them was to sing the guy a song. Now you have to give him money too? Pass.
    2.3TL, 3.1TL, SDA 2B, SDA II, 7B, 7C, 7 series 2, 10B, 5JR+, 5JR, 5A, 4.5, 4, RTA 11TL, RTA 8TL, RTA 8T, LSI9, LSI7 EBONY, LSI7 CHERRY, LSIC, RTI A7, RTI A3, CSI A4, CSI A6, F/XI A4, RTI4. That's all for now.
  • JayMXJayMX Posts: 124
    @la2vegas - if I actually sang, he would prob kick me out. He mentioned a hundo, ima see if I can talk him down a bit. Wish me luck!
    Upstairs 5.1.2:
    Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

    Downstairs 7.2.4:
    Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

    2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

    Office:
    Cambridge Soundworks Amp
    Monitor 4b (Peerless)

    Spares:
    Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

    Repair pile: SDA2, SDA1b
    ...and more to come, it’s a sickness.
  • la2vegasla2vegas Posts: 2,887
    May the force be with you.
    2.3TL, 3.1TL, SDA 2B, SDA II, 7B, 7C, 7 series 2, 10B, 5JR+, 5JR, 5A, 4.5, 4, RTA 11TL, RTA 8TL, RTA 8T, LSI9, LSI7 EBONY, LSI7 CHERRY, LSIC, RTI A7, RTI A3, CSI A4, CSI A6, F/XI A4, RTI4. That's all for now.
  • JayMXJayMX Posts: 124
    edited October 20
    Definitely B’s loaded with 6509’s. Pretty thrashed. Two bad tweets, three locked up mids. Cracked cabinet. Rough vinyl veneer. And free cobwebs! All for $80!! I will bring them back from the brink of death though. This I swear. 🤘🏻
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    Upstairs 5.1.2:
    Marantz NR1607, L/R - Modified Monitor 7C (194’s, Dynamat, Sonicaps, Mills, H-nuts), Center - Yamaha NS-C310, Surrounds/height/Atmos - (4x) Proficient in-ceiling, Sub - RBH TS10AN, Marantz DV7600

    Downstairs 7.2.4:
    Marantz SR6011, L/R B&W DM604, Center - RBH 700-CX, Surrounds - Monitor 5a (Peerless), Surround Back - Monitor 4a (Peerless), Height/Atmos - (4x) Polk RC60i, Sub#1 - JBL 12” frankespeaker, Sub#2 - Klipsch RSW12, Samsung bluray

    2CH: Kenwood KA-8150, Adcom GFA 555, L/R - SDA SRS 2, RTA12C (194's)

    Office:
    Cambridge Soundworks Amp
    Monitor 4b (Peerless)

    Spares:
    Monitor 10b (Peerless), Monitor 7b (Peerless), Monitor 5b (SL2000), Monitor 5b (SL1000)

    Repair pile: SDA2, SDA1b
    ...and more to come, it’s a sickness.
  • xschopxschop Posts: 874
    Halloween specials right there. Can't wait to see the resto-mod.
  • verbverb Posts: 3,681
    Nice find @JayMX ! Nothing that can’t be fixed! Just needs some love. Be sure to document your journey!
    Basement: Polk SDA SRS, Micro Seiki MB14 TT, VTL 2.5 Pre, Marantz CD6006 CDP, Conrad Johnson MF2300A Amp, Furman 15PFi Power Conditioner, AQ Diamondback (version 1) RCA IC's, MIT Terminator2 Bi-Wire speaker cables
    Office: PC, Cambridge CD transport, Marantz AMP-1, Acoustic Technologies Classic Speakers, Polk PSWi225 wireless sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable
    Spare Room: Dayens Ampino Integrated, Auris BluMe, Polk TSi200's
    Living Room: Pioneer SX-N30 Network Receiver, Pioneer PD10AE CD Player, Furman M8-LX Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi Subwoofer
  • honestaquarianhonestaquarian Posts: 2,007
    The very first SDA’s I ever owned were a pair of 1b’s that looked just like these. They forced me to buy a new Receiver as the impedance dips pretty low on these. I had a Realistic receiver (remember THOSE???) when I got these and it would play just fine until I turned up the volume. Then you would hear a loud *clack* come from the receiver and the sound would cut out (meaning the protection circuit would disconnect the amp from the signal path) Once I turned the volume down the sound would come back. I replaced it with an NAD receiver and was very happy (at least until a friend who liked to brag about his Luxman receiver accepted my challenge to bring it over and I discovered it sounded way better than my NAD! :s )
    Living room Home theater: Upgrade Company modified Onkyo PR-SC5509,Sunfire Cinema grand Signature 5 channel amp(1st gen),Carver TFM-45,Carver M-400a,Panasonic TC-P50ST60 50" Plasma(last gen before Plasma production stopped)Pioneer Elite DVL-91,Meridian 519 Dolby AC-3 RF Demodulator,Oppo Digital UDP-205,TiVo Bolt VOX,Nakamich BX-300,Technics SL-1200MKII,Shure V15 Type VxMR cartridge,Polk SDA-SRS 3.1 TL(with RD-0198 tweeters, upgraded with Larry's rings, black hole5,an Avel-Lindberg 1000VA isolation transformer, VR3 customer crossovers and internal wiring),Polk CS-1000P(with SL-6506 tweeter),Polk Monitor 5jr(with RD-0194 tweeters),Polk RT-35i (1),Polk Mini Monitors,Polk PSW150(4)Monster Power HTPS 7000 MKII Signature series,Monster Power AVS 2000 Signature Series,Various MIT,Monster,Upgrade Company and Belden interconnect,power,HDMI,Coax and Toslink Digital and speaker cables.

    Bedroom 2 channel system:Integra DTM 40.4,Nakamichi BX-100,TiVo mini,Musical Fidelity X-LPS,X-PSU,Carver TFM-25,Sony KV-34XBR970(last of the widescreen tube sets before production stopped)Technics SL-1200MKII,Shure V15 Type V MR cartridge,Polk RT-55(with SL-6506 tweeters),Polk PSW-200 in plexiglass(2),Sony Playstation 3 slim.Monster Power HTPS-7000,Monster AVS-2000, PowerVarious Kimber,Audioquest and MIT interconnects and speaker cables.
  • SchurkeySchurkey Posts: 1,770
    edited October 21
    Those serial numbers indicate that they can't be used with monoblocks.

    https://us.v-cdn.net/5021930/uploads/attachments/6/4/8/2/8/9806.jpg
    Malbec wrote: »
    These don't appear to be compatible with the isolation transformer.

    NOTE: Some early units of SDA-1C and all units of SDA-2B require plug adapters and some internal modifications to the crossover to be used with the Non-Common Ground Amplifier Interface. The affected SDA-1C units can be identified by serial number as follows:
    Right Channel #6001 through 6310 and #6501 through 6678 Left Channel #5975 through 6370 and #6532 through 6656

    If the serial numbers of your speakers fall within these limits, please contact Polk Audio for modification details.
    The early 1Cs are ABSOLUTELY compatible with an isolation transformer IF you are willing to add ~eight inches of wire and change the socket that the interconnect cable attaches to.

    In fact, if you're making your own interconnect cable to go with your Dreadnought, you just tie the ground side of the transformer to the negative binding post and you don't need the eight inches of wire inside the cabinet.

    Seems the "hot tip" is to remove the OEM socket for the interconnect cable, and replace it with a Speakon-style connector, so again you'd need a little wire added inside the cabinet.

    Many ways to skin this cat--IF these are early 1Cs. If they're 1Bs, you're pretty well screwed in terms of an isolation transformer.

    http://forum.polkaudio.com/discussion/131691/2b-and-early-1c-ai-1-modifications#latest

    Given the very-low serial numbers, I expect these are 1Bs, but a look at the midwoofer model numbers will confirm.

    I've had 1Bs since about 1986, bought them as "store demo" when the 1B was being replaced with the 1C. They're terrific-sounding speakers, even moreso when the crossovers are gone through, and you pull all the Dacron back up where it belongs, add the updated tweeters, etc.

  • F1nutF1nut Posts: 40,510
    Ummmm......."Definitely B’s loaded with 6509’s."
    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."


  • SchurkeySchurkey Posts: 1,770
    F1nut wrote: »
    Ummmm......."Definitely B’s loaded with 6509’s."
    Mia Culpa.
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