RT3000P Crossover

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I picked up a pair of these speakers last month that had the crossovers redone. Previous owner replaced stuff and just put back in cabinet with loose parts. They wanted to come back and mount everything to a new board but never did. I would like to mount everything to a piece of 1/2” MDF. I removed the crossovers tonight. I have the diagram for the crossover but still not 100% sure how to do it. Last crossover I did only had to replace one capacitor so fit back on original board. Previous owner said spent $200 per crossover. Didn’t look up prices gdvabtblwyi7.jpeg
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but does look like quality parts.
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Comments

  • pitdogg2
    pitdogg2 Posts: 24,559
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    That's some terrible looking work, no offense intended.
  • Polk_Denon
    Polk_Denon Posts: 27
    edited April 2023
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    pitdogg2 wrote: »
    That's some terrible looking work, no offense intended.

    Yeah it does look like crap. That was how the previous owner did it, that’s why I want to put everything on a new board. The one cross coil fell off the board when took it out of the cabinet
  • F1nut
    F1nut Posts: 49,794
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    Good Lord, what a mess.
    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

  • VR3
    VR3 Posts: 28,020
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    If you simply want to secure everything, remove it all and secure it to a mdf board and reinstall.if you want it to look like someone professionally assembled it? Deaolder everything and start over.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • VR3
    VR3 Posts: 28,020
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    The biggest problem I see is that there is no way those coils are a dcr match. This would change the voicing of the speaker tremendously, good or bad
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • pitdogg2
    pitdogg2 Posts: 24,559
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    VR3 wrote: »
    The biggest problem I see is that there is no way those coils are a dcr match. This would change the voicing of the speaker tremendously, good or bad

    I seriously was thinking the same thing.
  • Polk_Denon
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    VR3 wrote: »
    If you simply want to secure everything, remove it all and secure it to a mdf board and reinstall.if you want it to look like someone professionally assembled it? Deaolder everything and start over.

    That’s the plan. Never did a crossover before so even looking at the schematic, not sure how to lay all the parts out on the mdf board

  • Polk_Denon
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    It's not that difficult to have custom circuit boards made that can actually fit the components made. You need to have the original schematic and the dimensions of the coils, resistors and capacitors. I can help if you want to do it the correct way.

    I’d appreciate the help. Never did a crossover before so not sure on how to lay the parts out on a piece of mdf board.I have the schematic for these

    qt2wbnduox6a.jpeg
    235oidm02n5v.jpeg

  • F1nut
    F1nut Posts: 49,794
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    One huge problem you have is none of those inductors are correct. As previously noted, the DCR specs are way off.
    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

  • Polk_Denon
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    F1nut wrote: »
    One huge problem you have is none of those inductors are correct. As previously noted, the DCR specs are way off.

    If any of the parts are not correct, I will get the right stuff. Going to remove all the parts, hopefully tonight. Previous owner said his friend knew a lot about crossovers and he helped him with the parts but guess he didn’t know lol
  • pitdogg2
    pitdogg2 Posts: 24,559
    edited April 2023
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    Rather than trying to place everything on a piece of wood I would suggest having a printed circuit board made that would have all of the holes pre-drilled and plenty of space for each component. They can be made with the part number and line drawing of where each part is placed on the board. It might cost between $100.00 and $200.00 for the printed circuit board (called: PCB) file to be created (educated guess). And less than $50.00 to have 10 made.

    ummmm @gimpod had all kinds of trouble on his last go around for boards to get his correct....they were far more than that afaik
    Post edited by pitdogg2 on
  • VR3
    VR3 Posts: 28,020
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    Point to point is the way to go, IMO.

    As far as the inductors go... you can go to a lower DCR but it will change the sound. if you like the way they sound now... then... hey keep them and save the money. The parts quality is not in question
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • Polk_Denon
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    VR3 wrote: »
    Point to point is the way to go, IMO.

    As far as the inductors go... you can go to a lower DCR but it will change the sound. if you like the way they sound now... then... hey keep them and save the money. The parts quality is not in question

    Last night I hooked one up and compared it to another rt3000p I have that has the factory crossover parts yet. Sounded similar to me but then just had both sitting on workbench. Few months ago I had the ones hooked up in the living room that has factory crossovers yet, amps are bad in lower cabinets but thought the uppers sounds very good.
  • Polk_Denon
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    Ok got all the stuff removed from the board except the 2 blue caps. Here is everything….


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    fojod4r95ucu.jpeg

    dnzqa567df8s.jpeg
  • F1nut
    F1nut Posts: 49,794
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    Multicaps are SO yesteryear...yuck.
    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

  • Polk_Denon
    Polk_Denon Posts: 27
    edited April 2023
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    F1nut wrote: »
    Multicaps are SO yesteryear...yuck.

    What do you recommend?

    What is the cross coil? What did it replace on the schematic?
  • bcwsrt
    bcwsrt Posts: 1,591
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    From the 0.2 mH value, would appear to be the tweeter coil.

    Brian

    One-owner Polk Audio RTA 15TL speakers refreshed w/ Sonicap, Vishay/Mills and Cardas components by "pitdogg2," "xschop" billet tweeter plates and BH5 | Stereo REL Acoustics T/5x subwoofers w/ Bassline Blue cables | Rogue Audio Cronus Magnum III integrated tube amp | Technics SL-1210G turntable w/ Ortofon 2M Black LVB 250 MM cart | Sony CDP-508ESD CD player (as a transport) | LampizatOr Baltic 4 tube DAC | Nordost & DH Labs cables/interconnects | APC H15 Power Conditioner | GIK Acoustics room treatments | Degritter RCM
  • pitdogg2
    pitdogg2 Posts: 24,559
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    Polk_Denon wrote: »

    What is the cross coil? What did it replace on the schematic?
    It appears L1 in the tweeter circuit.
    Notice how that .2mh is .3 ohm.
  • Polk_Denon
    Polk_Denon Posts: 27
    edited April 2023
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    pitdogg2 wrote: »
    Polk_Denon wrote: »

    What is the cross coil? What did it replace on the schematic?
    It appears L1 in the tweeter circuit.
    Notice how that .2mh is .3 ohm.

    So it’s the wrong part compared to the original used from Polk?

    Looks like the red 3.0 coil is correct for the mids? Also the Mills 1 ohm resisters. Looks like is 2 on the mids but the resister on tweeter is 1.5 ohm. Am I looking at that correct?
  • F1nut
    F1nut Posts: 49,794
    edited April 2023
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    The inductor mH values appear correct, but the DC resistance (DCR) values are way off. All should be replaced with the correct values per the schematic.

    For the 3 and 9uF look at Sonicap Gen I or Clarity CSA. For the others due to the high values you'll likely have to stick with electrolytic caps.

    The resistor values are correct, you don't need to replace them.
    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

  • Polk_Denon
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    F1nut wrote: »
    The inductor mH values appear correct, but the DC resistance (DCR) values are way off. All should be replaced with the correct values per the schematic.

    For the 3 and 9uF look at Sonicap Gen I or Clarity CSA. For the others due to the high values you'll likely have to stick with electrolytic caps.

    The resistor values are correct, you don't need to replace them.

    Will take a look at those 3 and 9uf. What about the inductors?

    So it’s ok to use the mills 1 ohm resistor on the tweeter even though the schematic is a 1.5 ohm?
  • F1nut
    F1nut Posts: 49,794
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    I'm sorry, I thought you said you had a 1.5 ohm resistor already for the tweeter. If not, then yes it needs to be replaced with the correct value.

    For the inductors you will need to search online for ones that match the original values.
    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

  • Polk_Denon
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    F1nut wrote: »
    I'm sorry, I thought you said you had a 1.5 ohm resistor already for the tweeter. If not, then yes it needs to be replaced with the correct value.

    For the inductors you will need to search online for ones that match the original values.

    Will get a 1.5 ohm resister then. Looks like $10 from PE. What brands of inductors you recommend? Looked briefly on parts express from my phone but will have to search again when on the PC

  • F1nut
    F1nut Posts: 49,794
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    Whatever brand has the exact values required.
    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

  • Polk_Denon
    Polk_Denon Posts: 27
    edited April 2023
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    F1nut wrote: »
    Whatever brand has the exact values required.

    Was looking on PE at the inductors table and noticed solid core and air core. Does it matter which type use for the tweeter or mids?

    I did find a match for the one inductor on the mid(L3) 1.0MH DCR 0.3 ohm. Haven't found an exact match yet for the 0.2mh dcr 0.3 ohm or the 3.0mh dcr 1.25 ohm

    ms4tnttmdsf2.jpg
  • F1nut
    F1nut Posts: 49,794
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    Air core is better.
    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

  • Polk_Denon
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    Besides Parts Express, where are some other places to get inductors? They don’t have an exact match for the 0.2mh or 3.0mh
  • VR3
    VR3 Posts: 28,020
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    Hifi collective
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • Polk_Denon
    Polk_Denon Posts: 27
    edited April 2023
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    VR3 wrote: »
    Hifi collective

    no luck on that site either. When looking at the complete list on Parts Express I did see a .2mh dcr .29 On the schematic it's .2mh dcr .3 Would that work? Rated at 200 watts rms. How important is the wattage rating?

    With the 3.0mh I'm not seeing anything close to the 1.25 dcr on the schematic
  • F1nut
    F1nut Posts: 49,794
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    I believe you can custom order inductors from HiFi Collective and also try Parts Connexion.
    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