The Tale Of 5 Tweeters - SDA Tweeter Replacement Guide

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Comments

  • It seems like they're on there permanently, right?

    We know the feeling.

    The guys^ got ya.
    The Thrifty Setups in Mah House Big thrifty stereo in the basement w/ my custom SDA-1C (built with help from kind forum members) * Beautiful 1966 MCM GE console upgraded w/ Bluetooth, Dual turntable, and Paradigm speakers in family room * Swanky 1980 Realistic system and great TEAC eq with dancing colored lights in the living room * Ye Olde college stereo in the garage
  • ^ same here.
    A few of mine were so tight I thought I was going to break something. Used a flat tip screwdriver as a pry to break the initial hanging on for dear life connection, then came off easy.
  • lzuo
    lzuo Posts: 3
    edited December 2022
    The prying with a flat head screwdriver idea is genius! One tweeter is replaced. One more to go. :)
  • Woohoo!

    Shared knowledge from shared stress = solutions to problems!
    The Thrifty Setups in Mah House Big thrifty stereo in the basement w/ my custom SDA-1C (built with help from kind forum members) * Beautiful 1966 MCM GE console upgraded w/ Bluetooth, Dual turntable, and Paradigm speakers in family room * Swanky 1980 Realistic system and great TEAC eq with dancing colored lights in the living room * Ye Olde college stereo in the garage
  • F1nut
    F1nut Posts: 49,560
    edited December 2022
    Most current fastons have a tiny clip that must be squeezed to remove it, but the vintage Polk fastons do not have them. Yours should pull right off. Try wiggling them a bit first.

    Edit: didn't see page 5 before I posted.
    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

  • Gardenstater
    Gardenstater Posts: 4,096
    edited March 2023
    Cool and nice speakers there! The top tweeter is the RD0194 and the lower one is the Peerless KO10DT, which Polk sometimes referred to as HF1000 or even SL1000 (in at least one informational advertisement in an audio magazine). The later made their own tweeter which they called SL1000 which was used as the replacement for the Peerless when they stopped making it in early 1983.

    The Polk RD0194 is not generally considered a replacement for the Peerless although it gets a little convoluted in my opinion, when Polk says the SL1000 was a replacement for the Peerless and the RD0194 is a replacement in specs but not size for the SL1000. It does get a bit bizarre.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Crown D150 amp
    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
  • Emlyn
    Emlyn Posts: 4,329
  • Wowza.
    The Thrifty Setups in Mah House Big thrifty stereo in the basement w/ my custom SDA-1C (built with help from kind forum members) * Beautiful 1966 MCM GE console upgraded w/ Bluetooth, Dual turntable, and Paradigm speakers in family room * Swanky 1980 Realistic system and great TEAC eq with dancing colored lights in the living room * Ye Olde college stereo in the garage
  • Gardenstater
    Gardenstater Posts: 4,096
    How well do those Primacoustic Isolation Pads work? Are these the ones you have?:

    https://www.sweetwater.com/store/detail/RX9f--primacoustic-rx9-monitor-isolation-pads-15-inch-by-11-inch-flat
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Crown D150 amp
    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
  • harmonic
    harmonic Posts: 6
    What's your opinion, forum: should I put the "old" Peerless back in, or stick with the RD0194? I also plan to recap the crossovers but haven't yet. (Usually when big e-caps fail, like in a power supply, it's pretty obvious; here not. I do have a capacitor tester so I'll be able to see exactly where they're at. They are 40 yrs old... With PS caps you're lucky to get 10-12 years out of em, but that's quite a different usage profile.)

    Re the Primacoustics. Yes, they're the RX9 and REW showed considerable improvement over the Auralex MoPADS. But even more mass would be better, eg a granite countertop remnant... I'm gonna circle back around on that thought later, doing some experiments after dampening the table they're on with bricks behind the monitors. But that may not be necessary once I solve the dominant problem in this room: low frequency modes, thanks to the dimensions. Next house will have a properly irregular shape....

    The back of this room has 6 Auralex T-Fusors, which may or may not stay after I put up the rest of the absorption in between them. There are newer and fancier diffusor designs, if you have the space for them, e.g., quadratic-residue defusers (QRD) and even Auralex has a newer model. So the room is set up in a dead-live configuration, where the mix position forward is "dead" via heavy absorption and the back of the room is 50/50 absorption/defusors. If that turns out to be too live, I can swap out any/all of the 2'x2' defusers for 2'x2' 4-inch cloth-covered mineral fiber panels.

    But I digress! Low-frequency (below 125Hz) needs more than even 4" acoustic foam; it needs bass traps, e.g., Helmholz resonator or diaphramic panel resonator. The design of these is fascinating! Both of these types of bass traps are constructed and tuned to a very specific frequency - in my case 42.5 Hz. Once I get that energy from bouncing back on itself and canceling out, aka standing wave, *then* I'll really be able to tell you if the Primacoustics were all I need. :-) I do know that they're better. My Sweetwater guy tells me that the RAB approach works very well, too. https://www.sweetwater.com/store/detail/Aperta200Bk--isoacoustics-aperta-200-isolation-stands-black-pair

    Sorry, I'm probably boring you all to death! If there's interest I can post some of my room acoustic measurement, made with a miniDSP UMIK-1 reference microphone (~$100) and the awesome and free Room EQ Wizard software (REW) https://www.roomeqwizard.com/index.html#.

    It's nerdy fun - but essential if you're trying to create a "critical listening environment." You'll also want a copy of "Master Handbook of Acoustics" [Everett]. While there's ample room for math geeking in the theory, you really don't need much more than arithmetic to measure and interpret room measurements. And there are even experts who will analyze it for you (hoping you buy their products, of course)

    -- jdm
  • F1nut
    F1nut Posts: 49,560
    The RD0194-1 is not a replacement for the Peerless. Besides that, your RD0194-1 doesn't fit the cut out making it a sonic and visual disaster.
    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

  • harmonic
    harmonic Posts: 6
    i'm not sure what you base that on. Polk sold me the RD0194 as an "upgrade" when I contacted them to get new speaker grill cloth - sometime in the 1980s, as I remember we were at our first house and the '11's were still just my stereo speakers. So clearly *they* thought it was a replacement.

    As far as the cutout, no, the cutout is just fine, as you can see by the pictures, where one has the Peerless, one has the RDO104. the only diff was that I had to drill two new holes for the RD0194's very slightly vertically-higher holes. I kept the same gaskets, even, and can post a pic if you like.

    Re which one is "better" I'm curious as to all y'all's opinion, if your opinion is based on listening tests (which are still notoriously difficult to do correctly). As an engineer by trade, so I will also be gathering data via REW to see if that tells us anything. Little wiggles are largely inconsequential and not a good basis for deciding "better." The final arbiter, of course, is how it sounds, subjectively. A famous recording engineer once said about the "right" settings for this or that, "if it sounds good, it *is* good; I don't care if you have to turn the knob around backwards!"

    We put a lot of stock into specs and charts for our audio gear, but there are many limitations to that, of course. For one, what we perceive is much (much) less than what test gear can measure. For example, raw frequency plots will show crazy lines, but the standard for comparing them is to use 1/3 octave smoothing, which is at least closer to our perception. Then there's the question of loudness on how we perceive frequency, i.e., Fletcher-Munson curves, and that includes not just volume but program material, too. But the really big biggie in whatever you are hearing is the effects of an untreated room. You can easily have peaks and troughs of *tens* of dB - and those likely change radically when you move your head 1ft.

    Of course I'm not saying that we shouldn't all strive to have good specs, only that there are a lot of other things that will impact the quality of what you hear under real-world conditions, so a wiggle in a speaker's frequency plot will likely matter a whole lot less than it looks like it might on paper. Realize that the world's most coveted microphones and preamps are coveted precisely *because* of their non-linearity, many extremely so. (And non-linearity here is not just frequency response, but also in distortion. Yes, that's right; while audiophiles are busy trying to spend their way to some sort of sonic purity Nirvana, recording engineers are busy running individual tracks and even the entire mix through distortion-inducing processes - analog tape, tube preamps, even guitar stomp boxes - on purpose!)

    Even in professional mixing & mastering environments, where the nominal goal is to have a "neutral" listening environment, there are very different, equally valid approaches. Some like the "non-environment" approach, where you try to come as close to an anechoic space as possible to "take the room out of it." More in vogue these days is the live-end/dead-end, using sophisticated, typically large diffusors, to instead make the room part of it, but make the room sound like a much bigger, better-behaved room. Unforuntately, that requires a lot of space - but could be quite useful in a large home theater or dedicated listening room. Or your living room, if your wife is very (very) understanding!

    As there are different approaches to the space itself, professional environments have even more variety for monitors. Most studios have big, fancy monitors as well as small, cheap speakers more representative of what their listeners will hear. I was surprised to learn that many producers use these "crappy" speakers 80% of the time or more, only listening loudly on the big speakers to check - and for fun, or to show off for clients or the label A&R guys. If you look in the middle of that pic I posted, you see two square speakers; these are Auratones, aka "Horror Tones" - single-driver speakers that have become a de facto standard for these crap speakers, or "grot boxes."

    At the end of the day, if you're mixing professionally, your mix has to work well on other people's systems, so you need a) a room that doesn't lie, and b) speakers you know like the back of your hand. Many producers carry a pair of speakers around with them to satisfy "b" - and these speakers aren't always so great: the Yamaha NS-10 became the industry standard near-field monitor a few decades ago, and a lot of producers still use them, notably Chris Lord-Alge, who now has is own line of 'em, called CLA-10. And since all the cool kids have gone to powered monitors, he also endorsed his own Class-AB power amps, like the CLA-200 I use with my Model 11s. Not coincidentally, both the speakers and the amps are made by Avantone, who now produces their own Auratone clones. Neither the Yamaha NS-10 or Auratone cubes are being made by their respective companies, anymore. My point being, Chris Lord-Alge (very accomplished producer) has spent so many years with NS-10s that he went to the extreme of starting a product line to keep making them - not because they're awesome sounding (they're not) but because he knows exactly what they're saying to him.

    So, at (very) long last is the point I've been getting to: regardless of which these tweeters is "better" - or, more broadly, if other monitors are better (as I said, all the cool kids are using powered near-fields in their studios now - and I don't know any others that are using Polks of any kind), your ears get used to and familiar with the one you've been using. Think about all the great music that was produced over many decades on speakers much (much) less capable than what you already have.

    If it sounds good, it *is* good! (And clearly I think Polks sound good, or I wouldn't keep using them in so many places - and in "critical" environments.)

    cheers,

    -- jdm
  • F1nut
    F1nut Posts: 49,560
    edited March 2023
    .
    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

  • xschop
    xschop Posts: 4,473
    Post 48,156 will go down in history... F1 lost words.
    Don't take experimental gene therapies from known eugenicists.
  • harmonic
    harmonic Posts: 6
    So I spent the entire bloody afternoon setting up REW tests, pitting the HF1000 (aka Peerless) vs. the RD0194 in my Model 11. I'll post the equipment and pictures of methods after this, but here is the plot of frequencies - which isn't the whole story, of course, but I thought it interesting given the attention paid to the "out of body" frequency response charts earlier in this thread, posted by DarqueKnight, e.g., (https://forum.polkaudio.com/discussion/182943/the-tale-of-5-tweeters-sda-tweeter-replacement-guide/p2). Nice work, DarqueKnight! Most people don't realize how much work goes into these kinds of things!

    What struck me was that opinions - sometimes strong opinions - were formulated based on these test, outside any speaker enclosure or even crossover. i.e., purely a spec sheet on the tweeter. One could quibble about the acoustic environment being untreated, and I didn't see any mentioning of impulse gating to filter reflections, but no matter; they were all tested the same.

    Since that work had already been done, I tested these two tweeters in the speaker cabinets (i.e., how one would actually use them) including the crossovers. I controlled for a number of variables (which I'll discuss) except for using the Left speaker for one and the Right speaker for the other. But they were tested in the exact same spot and setup.

    So here's the freq chart. Guess which plot is which tweeter? And which one would you say is "better" and why?

    3v5dslg6bp9g.png
  • harmonic
    harmonic Posts: 6
    Testing setup - pics first4dfhw6fhidc7.jpeg
    6xcf792ychvc.jpeg
    uydkz2mi48t5.jpeg
    7s9umq2y893v.jpeg

  • xschop
    xschop Posts: 4,473
    Orange/Yellow is the Peerless? A little less 'peaky', probably due to the metal bezel vs the crap plastic.
    Don't take experimental gene therapies from known eugenicists.
  • harmonic
    harmonic Posts: 6
    Tweeter testing setup:
    1. Room EQ Wizard (REW) on Mac, MacOS Ventura
    2. UMIK-1 USB calibrated test microphone
    3. Auralex acoustic foam "gobos"
    4. Universal Audio Apollo x8 multichannel audio interface
    5. Avantone CLA-200 power amp
    6. Milesey laser tape measure
    7. earplugs :-) As you can see from the chart, testing was done at quite high level. (Mixing/mastering these days has pseudo-standardized on 83dbC (or 85dbC for larger rooms), so this is louder than I normally work at.

    With this setup I controlled for:
    1. positional variation (i.e., both speakers were placed in the exact same spot in the room, with the same acoustic treatments)
    2. distances, both from the measurement mic to the tweeters (30cm) and distance to the floor (1.391m)
    3. using these calculations and the handy floor/ceiling reflection calculator at (https://mehlau.net/audio/floorbounce/), I controlled for floor reflections by setting the Right side of the IR Window. i.e., by knowing those distances, you can know how soon any reflection will come back to you. Setting that window sets a lower bound for how low of frequency you can test for. In this case, the first reflection would be at 72.41ms and thus we had a lower bound of 6.9 Hz. Pretty safe for tweeter testing ;-)

    I'm surely forgetting something, but you get the idea.
  • F1nut
    F1nut Posts: 49,560
    xschop wrote: »
    Post 48,156 will go down in history... F1 lost words.

    Nope, decided not to waste my time on someone listed.
    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

  • Gardenstater
    Gardenstater Posts: 4,096
    edited March 2023
    xschop wrote: »
    Orange/Yellow is the Peerless? A little less 'peaky', probably due to the metal bezel vs the crap plastic.

    My guess too (sticking my neck out). I think there will be some diffractions from that RD0194 due to the fact that it is not recessed in the cutout and cannot be flush with the baffle.

    Less smoothing would probably reveal it even more.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Crown D150 amp
    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
  • xschop
    xschop Posts: 4,473
    F1nut wrote: »
    xschop wrote: »
    Post 48,156 will go down in history... F1 lost words.

    Nope, decided not to waste my time on someone listed.

    That's great news. Thought we lost you to post gene therapy induced apraxia.
    Don't take experimental gene therapies from known eugenicists.
  • harmonic
    harmonic Posts: 6
    xschop wrote: »
    Post 48,156 will go down in history... F1 lost words.

    Sorry, I've been indisposed; didn't mean to leave all y'all hanging.

    The Orange is the RD0194; the blue is the Peerless.
  • F1nut
    F1nut Posts: 49,560
    xschop wrote: »
    F1nut wrote: »
    xschop wrote: »
    Post 48,156 will go down in history... F1 lost words.

    Nope, decided not to waste my time on someone listed.

    That's great news. Thought we lost you to post gene therapy induced apraxia.

    Would you like to buy a vowel?
    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

  • xschop
    xschop Posts: 4,473
    F1nut wrote: »
    xschop wrote: »
    F1nut wrote: »
    xschop wrote: »
    Post 48,156 will go down in history... F1 lost words.

    Nope, decided not to waste my time on someone listed.

    That's great news. Thought we lost you to post gene therapy induced apraxia.

    Would you like to buy a vowel?

    I just had a steak and beer at Joe's real inflationary rate , I'm wiped out.
    Don't take experimental gene therapies from known eugenicists.
  • xschop
    xschop Posts: 4,473
    I'll have to hold off buying that vowel again...

    ect5tu0tej8i.jpg
    Don't take experimental gene therapies from known eugenicists.