Tweeter replacement for RTA 12B. This question may have been answered a thousand times before......

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dinocgeo
dinocgeo Posts: 8
in Vintage Speakers
Hi all. There's so many opinions or different answers on this. I've called polk customer service and they say there are no current replacement parts for the RTA 12B because it's so old now. Just look on ebay they say. Well, that's all good, but what would be the closest replacement tweeter for the 12B to try to get a hold of from ebay? The ones I have right now are perhaps the Peerless and seem to have the little hole in the middle of the dome. They do work, but I'd like to be able to have an idea of replacement parts just in case.

3pgjx7p2r1lk.jpg

Thanks to anyone who replies.
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Answers

  • Gardenstater
    Gardenstater Posts: 4,203
    edited August 2022
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    There isn't anything that I would attempt to substitute for the Peerless and ebay was the correct answer. Just make sure you get the 8ohm variety and try to get one from a Polk and that it has the hole (nobody else did the hole mod). Make sure they pack it in non-shedding material with a hole in it to protect the dome. I had a knucklehead on eBay send me one that had styrofoam particles and chopped glass fibers all over the sticky dome :s Was a lot of work to remove them one by one with sticky tape. It would've been so easy to just stick the tweeter first into a sandwich bag.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • dinocgeo
    dinocgeo Posts: 8
    edited August 2022
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    Thanks for replying. So the peerless "copy" or any other from Midwest Speaker Repair are not up to par with the original Peerless I guess? Don't seem to be many originals floating around at the moment.
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  • Gardenstater
    Gardenstater Posts: 4,203
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    It will not have the hole. Aside from that I don't know anyone that has taken a chance on those made in China "copies".
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • Gardenstater
    Gardenstater Posts: 4,203
    edited August 2022
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    I see a few but those don't have holes. Here's one that looks good except for a very slight crease that shouldn't affect SQ at all: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • dinocgeo
    dinocgeo Posts: 8
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    What was/is the purpose of the hole?
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  • dinocgeo
    dinocgeo Posts: 8
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    Gardenstater wrote: »
    I see a few but those don't have holes. Here's one that looks good: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs

    Thanks for that. I see that it's a "5514" I wonder if that would have a slightly different sound compared to the 7514...
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  • Gardenstater
    Gardenstater Posts: 4,203
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    Well depends upon who you talk to but I tend to prefer Polk's own advertising copy for my explanation. Note they hurt their credibility a tad by misidentifying the thing as an SL1000 LOL:

    1m02zdxe8rjk.jpg
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • xschop
    xschop Posts: 4,725
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    Gardenstater wrote: »
    It will not have the hole. Aside from that I don't know anyone that has taken a chance on those made in China "copies".

    Talking about the Wuhanless?
    Don't take experimental gene therapies from known eugenicists.
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  • pitdogg2
    pitdogg2 Posts: 24,630
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    If the peerless you buy doesn't have a hole you can always add one. Polk used a soldering iron the burn a hole in the dome.
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  • dinocgeo
    dinocgeo Posts: 8
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    xschop wrote: »
    Gardenstater wrote: »
    It will not have the hole. Aside from that I don't know anyone that has taken a chance on those made in China "copies".

    Talking about the Wuhanless?

    I don't know what that is.
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  • Tony M
    Tony M Posts: 11,019
    edited August 2022
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    Here's all you will need to read to understand what they are. ;)

    They are pretty good and cheap domes to replace certain old polk tweeters (SL2000) but unfortunately, I don't think they can replace Peerless domes in their magnet structures.

    https://forum.polkaudio.com/discussion/168239/a-real-sl-2000-hack-replace-stock-burnt-voice-coils-with-silk-diaphragm-dome/p1
    Most people just listen to music and watch movies. I EXPERIENCE them.
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  • Gardenstater
    Gardenstater Posts: 4,203
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    dinocgeo wrote: »
    Gardenstater wrote: »
    I see a few but those don't have holes. Here's one that looks good: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs

    Thanks for that. I see that it's a "5514" I wonder if that would have a slightly different sound compared to the 7514...

    If the dates of manufacture are close and the DC resistance measure very close or the same, that is all I would worry about.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
    · Share on FacebookShare on Twitter
  • dinocgeo
    dinocgeo Posts: 8
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    Gardenstater wrote: »
    dinocgeo wrote: »
    Gardenstater wrote: »
    I see a few but those don't have holes. Here's one that looks good: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs

    Thanks for that. I see that it's a "5514" I wonder if that would have a slightly different sound compared to the 7514...

    If the dates of manufacture are close and the DC resistance measure very close or the same, that is all I would worry about.

    I read that the 7514 was manufactured in Demark and the 5514 in the USA but they seem to be the same tweeter.
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  • Gardenstater
    Gardenstater Posts: 4,203
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    dinocgeo wrote: »
    Gardenstater wrote: »
    dinocgeo wrote: »
    Gardenstater wrote: »
    I see a few but those don't have holes. Here's one that looks good: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs

    Thanks for that. I see that it's a "5514" I wonder if that would have a slightly different sound compared to the 7514...

    If the dates of manufacture are close and the DC resistance measure very close or the same, that is all I would worry about.

    I read that the 7514 was manufactured in Demark and the 5514 in the USA but they seem to be the same tweeter.

    Well I have been gathering info. on that....mostly eBay seller's pictures.......and I have pictures of 7514s that also have a Made In USA sticker on them, and I have 5514s that are date coded before manufacture was taking place in the USA at all.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • dinocgeo
    dinocgeo Posts: 8
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    Gardenstater wrote: »
    dinocgeo wrote: »
    Gardenstater wrote: »
    dinocgeo wrote: »
    Gardenstater wrote: »
    I see a few but those don't have holes. Here's one that looks good: https://www.ebay.com/itm/144645015288?hash=item21ad83c6f8:g:74YAAOSwrsViz2zs

    Thanks for that. I see that it's a "5514" I wonder if that would have a slightly different sound compared to the 7514...

    If the dates of manufacture are close and the DC resistance measure very close or the same, that is all I would worry about.

    I read that the 7514 was manufactured in Demark and the 5514 in the USA but they seem to be the same tweeter.

    Well I have been gathering info. on that....mostly eBay seller's pictures.......and I have pictures of 7514s that also have a Made In USA sticker on them, and I have 5514s that are date coded before manufacture was taking place in the USA at all.

    I'm tempted to buy the one on ebay, that you found, just not sure right now in case it doesn't have the same sound. They look identical in everyway though.
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  • Gardenstater
    Gardenstater Posts: 4,203
    edited August 2022
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    Compare the date codes and the DCRs. If they are close I wouldn't worry. If the dates aren't close you could still buy a matching pair of Peerless as long as the DCRs are close to your ones currently in the speakers.

    PS: the date code on that one on eBay I gave the link to is 5th week in 1982 and he measures 7.6 Ohm with a fluke DVOM.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
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  • dinocgeo
    dinocgeo Posts: 8
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    The manufacture date is the same year...5 months apart
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  • Gardenstater
    Gardenstater Posts: 4,203
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    Not too far apart. DCR is most critical I'd say. I've bought some that measured as low as 6.8 Ohms and that is not a match for the ones I had that came with my speakers, which measured about 1 Ohm higher, and they did indeed sound brighter.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
    · Share on FacebookShare on Twitter