Monitor 7 opened up to find a surprise

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ratpin
ratpin Posts: 85
in Vintage Speakers
I’m currently gluing a bunch of my mid drivers magnets.

I’ve had these M7’s for a few years and thought I tested them when I got them but can’t remember for sure. Anyway I opened one up to find something unusual inside. See picture. Any thoughts?

pipi5o0fmpxm.jpeg

3s4n7nc2bhzj.jpeg



Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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Comments

  • msg
    msg Posts: 9,475
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    Huh?
    No crossover?
    I disabled signatures.
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  • xschop
    xschop Posts: 4,720
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    5Jr crossover
    Don't take experimental gene therapies from known eugenicists.
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  • ratpin
    ratpin Posts: 85
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    Anyone have a spare M7B crossover?
    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • ratpin
    ratpin Posts: 85
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    m9cnse9j73lv.jpeg
    imsi0g6a5e9e.jpeg
    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • ratpin
    ratpin Posts: 85
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    Here’s a picture of the crossover in the other cabinet. This is the one I guess I need.

    irkn3x2p2ezl.jpeg
    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • xschop
    xschop Posts: 4,720
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    Im REALLY curious if the 5Jr crossover has the 34uf, 12uf caps and 2 ohm resistor grafted in?
    Don't take experimental gene therapies from known eugenicists.
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  • Toolfan66
    Toolfan66 Posts: 16,938
    edited August 2023
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    I would like to see the other side of that crossover.
    Post edited by Toolfan66 on
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  • ratpin
    ratpin Posts: 85
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    Toolfan66 wrote: »
    I would like to see the other side of that cross over.
    .

    Seems like this is as much as I can get without de-soldering.

    0uuknv9j8863.jpeg
    bt38k9pj7kwx.jpeg


    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • Toolfan66
    Toolfan66 Posts: 16,938
    edited August 2023
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    Ratpin,

    I will be upgrading my 7’s soon, and I plan on doing a point to point crossover, I am waiting on some inductors from HiFi Collective, if it looks like all will go as planned I will gift you a crossover, if you don’t find one between now and then.
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  • Gardenstater
    Gardenstater Posts: 4,195
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    Yes we need a view of the binding post side and underneath that PCB on the components side. The very early 7s had part of the crossover on the back of the tweeter, not that I'm saying that is what this is.

    You have Monitor 7Cs.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
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    Crown D150 amp
    Logitech Squeezebox Touch Streamer w/EDO applet
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    Custom Steve Wilson 1m UPOCC Interconnect
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    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
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  • ratpin
    ratpin Posts: 85
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    Toolfan66 wrote: »
    Ratpin,

    I will be upgrading my 7’s soon, and I plan on doing a point to point crossover, I am waiting on some inductors from HiFi Collective, if it looks like all will go as planned I will gift you a crossover, if you don’t find one between now and then. It is a perfect match to what you have..

    That would be great! And no I’m not in a hurry. Thank you!

    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • Toolfan66
    Toolfan66 Posts: 16,938
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    08osl0otny8g.jpeg
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  • ratpin
    ratpin Posts: 85
    edited August 2023
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    Yep that’s exactly what’s in the other cabinet.
    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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  • ChrisD06
    ChrisD06 Posts: 886
    edited August 2023
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    ratpin wrote: »
    Toolfan66 wrote: »
    I would like to see the other side of that cross over.
    .

    Seems like this is as much as I can get without de-soldering.

    0uuknv9j8863.jpeg
    bt38k9pj7kwx.jpeg


    That's indeed a 5JR/+ Series 1 crossover.

    h1z4o3c8vxza.jpg
    d62q4us283rm.jpg

    It doesn't appear to have any components from the M7 grafted on like Rob asked.

    Also you can get it further than that without desoldering. The resistance is just slack copper wire from the large inductor being very stiff. You can lift it straight up and it'll come out alot further.

    M5JR board is a PITA to rebuild. Anyhow, it looks like you'll be needing to find the correct crossover or make this one spec-compatible.
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  • Toolfan66
    Toolfan66 Posts: 16,938
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    Toolfan66 wrote: »
    08osl0otny8g.jpeg

    Not sure if you received my PM, but I shipped this crossover to you today..
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  • ratpin
    ratpin Posts: 85
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    Thank you!
    Polk: / SDA-CRS / SDA-1C / M-10B / M-7B / M-5 / M-5jr / RTA-11T / LSIM703 / LSIM704 / LSIM706 / RTI8 / CSI3 / CSI5 / RTI4 / RTI-A5 / CSI-A6 / RC80i / RC85i / RC6s / PSW300 / Atrium6 / Atrium4 / About a dozen pair of Atrium45 lol.
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