Monitor 10A Crossover Upgrade/Fix

I've read that updating the crossovers makes a big impact on these speakers. Also, one of the two speakers' binding posts are gone with speaker wire soldered in place. This is how they were when I bought them. It works, but it's not ideal. (I've repaired the broken wire seen in the photo.)

I'm a dummy when it comes to understanding electronics, but I'm comfortable soldering when I know I have the right parts going in the right place. So, I'm looking for help identifying which parts to replace, what to replace them with, and what to do, if anything, about the binding posts.

eld9sqrfo12t.jpg
yy9n1m02k7o0.jpg
x5chan410jgk.jpg
«1

Comments

  • JayCee
    JayCee Posts: 1,474
    hazyIPA wrote: »
    I'm a dummy when it comes to understanding electronics, but I'm comfortable soldering when I know I have the right parts going in the right place. So, I'm looking for help identifying which parts to replace, what to replace them with, and what to do, if anything, about the binding posts.

    Welcome to Club Polk, @hazyIPA! I'll start by saying I love a good hazy IPA.

    Sounds like you have the basic skills to redo the XO's. Never had your 10A's but have modded multiple sets of Polks. I'm not too original so just got my read on using CP and did the "monkey see, monkey do" blueprint of other Club Polk members.

    Should be an easy upgrade and given the age of the speakers definitely in need of refresh, which will do wonders for the sound. Source the same value caps and resisitors. Sonicaps (http://www.soniccraft.com/index.php/sonicap-m-21) and Mills resistors are the preferred offerings but you'll also find lovers of other caps on CP.

    Binding posts can be upgraded but are not an immediate necessity. I have spare OE posts in my parts stash you can have for free, if you want to stay stock. Once you get your post count up and are able to PM I'd be happy to drop them in the mail if you send me your address.

    Also, consider upgrading the tweeters to replacement offerings from Polk depending on what you have. I'll let other's chime in with more experience w/the 10A's but in the meantime get your read on:

    https://www.google.com/search?q=club+polk+monitor+10a+crossover+upgrade+site:forum.polkaudio.com&sa=X&ved=2ahUKEwjlg9Xb95fnAhXQCTQIHcRPB9EQrQIoBDAAegQIBBAP&biw=1089&bih=735

    Again, welcome to the forum!

    John
    Speakers: Polk1.2tl's (Uber Mods) Pre/Amp/DAC: PS Audio BHK Signature & 250, DirectStream Cables/IC's: MIT S1Bi-Wire/S1 Balanced +Avel Lindberg 1000VA "Dreadnought" Power Conditioner: PS Audio P15 Power Plant Power Cords: Core Power Technologies Gold, DH Labs Power Plus DIY w/Neotech NC-P301 & P311ends Streaming: Roon ROCK on wifi'd NUC, TP-Link WAP, & Uptone EtherREGEN, AfterDark, Emperor Double Crown Clock, Black Modernize LPS, PS Audio AirLens⟿Ω☯☥☮⟿🔊♩♪♫♬♩♪♫♬♩♪♫♬
  • pitdogg2
    pitdogg2 Posts: 24,474
    10a should have the Peerless tweeter, nothing to upgrade there.
  • JayCee wrote: »
    Source the same value caps and resisitors.

    So, looking at the photo below, should all six parts be replaced? Which ones are capacitors / resistors?

    48o4iudu4smq.jpg

    And, thanks for the warm welcome!

  • Welcome to the forum Hazy IPA the item number 4 is an inductor no need to replace. The other items are either capacitors tube shaped or resistors rectangle shaped, much better parts are available do a search and you will see what I mean.
    Yamaha RXA1030, Yamaha CD-S2100, Yamaha AS-2200, Bluesound node 2i
    Polk SDA2btl highly modded
    Polk SDA 1C modded
    Polk CS350 LS x2
    Kimber 8TC
    Sony 55" Bravia
    Wish list SVS sub

  • JayCee
    JayCee Posts: 1,474
    edited January 2020
    hazyIPA wrote: »
    JayCee wrote: »
    Source the same value caps and resisitors.
    So, looking at the photo below, should all six parts be replaced? Which ones are capacitors / resistors?
    • Caps-2, 5, 6
    • Resistors-1, 3
    • Inductor-4
    As RandyCroissant stated, the inductor is not necessary to replace. There are better but are a bit tricky as you need exact values that are very critical to the voicing of the speaker. If inclined, replace at a later time with the expectation of lesser improvement. The caps and resistors result in the most immediate improvements.

    Caps can be replaced with values that are within 10% of what's printed on the cap, perfectly fine to do and within tolerances of how Polk did it, too. If one of the values is large, cost prohibitive or not available, you can combine 2 caps of lesser values, wired in parallel, to equal the required value. Example, 52 μF can be created w/2 26 μF caps. Of note for caps, depending on the manufacturer you choose and physical size, a challenge may be being creative when mounting the new cap(s) to the XO board. Don't let this dissuade you...IMO, it's part of the fun working with these old boards.
    Speakers: Polk1.2tl's (Uber Mods) Pre/Amp/DAC: PS Audio BHK Signature & 250, DirectStream Cables/IC's: MIT S1Bi-Wire/S1 Balanced +Avel Lindberg 1000VA "Dreadnought" Power Conditioner: PS Audio P15 Power Plant Power Cords: Core Power Technologies Gold, DH Labs Power Plus DIY w/Neotech NC-P301 & P311ends Streaming: Roon ROCK on wifi'd NUC, TP-Link WAP, & Uptone EtherREGEN, AfterDark, Emperor Double Crown Clock, Black Modernize LPS, PS Audio AirLens⟿Ω☯☥☮⟿🔊♩♪♫♬♩♪♫♬♩♪♫♬
  • tonyp063 wrote: »
    This is a good thread to look through.
    I will open mine up to confirm, but looking at tonyp063's helpful link, it looks like the values and my guess at replacements could be:
    1. 2.5 ohm resister - link
    2. 34 uF capacitor - link
    3. 2.7 ohm resister – link
    4. Inductor – Keep Original
    5. 12 uF capacitor – link
    6. 34 uF capacitor – same as #2
    Do those replacement look right? And, what level of “Precision Matching” would you suggest?

    JayCee wrote: »
    a challenge may be being creative when mounting the new cap(s) to the XO board.
    That definitely seems to be true looking at other crossover upgrades!
  • tonyp063
    tonyp063 Posts: 1,044
    Don't buy components until you look at what's actually in yours.
    L1 precision is fine. Don't forget that Polk used, at best, 10% back when.

    Don't forget binding posts too.
  • Gardenstater
    Gardenstater Posts: 4,136
    @hazyIPA be careful as I checked your links and the values are wrong. Check the decimal places. Gonna be quite a bit more expensive than those :#
    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
  • Gardenstater
    Gardenstater Posts: 4,136
    @tonyp063 I am also doing what the OP is doing, but on a pair of 7Bs. What binding posts would you recommend? Been checking prices and WOW !
    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
  • tonyp063
    tonyp063 Posts: 1,044
    heh. Yeah, The price diff between a 0.0033uF & a 33uF is *rather* significant.

    Cardas are not cheap, no.
    I used Solens when I did mine because I was getting my parts from Parts Connection
  • @hazyIPA be careful as I checked your links and the values are wrong. Check the decimal places.
    Doh! Good catch! How's this list looking now?
    1. 2.5 ohm resister - 2.5 Ohm Vishay Mills 5 watt MRA-5
    2. 34 uF capacitor - Gen I Sonicap 34 uF 200VDC
    3. 2.7 ohm resister – 2.7 Ohm Vishay Mills 5 watt MRA-5
    4. Inductor – Keep Original
    5. 12 uF capacitor – Gen I Sonicap 12 uF 200VDC
    6. 34 uF capacitor – same as #2
    I'll be sure to check the values on my speakers before moving forward.
  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    @tonyp063 Thank you. Found 'em and the price is reasonable. Gold plated brass and they have a male faston tab, probably .205". I guess to get gold plated copper billet you have to spend much much more. Don't know if the difference is audible?

    Oh could you tell me if they are for 1/4" ring terminals/spades or 5/16" ?

    https://www.partsconnexion.com/SOLEN-51541_ss43741.html

    5nldupj9hmji.png
    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
  • F1nut
    F1nut Posts: 49,707
    Copper billet with direct gold plating. Worth every penny.

    http://www.soniccraft.com/product_info.php/cardas-ccgg-binding-post-p-1387
    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

  • tonyp063
    tonyp063 Posts: 1,044
    @hazyIPA

    go for the 12W resistors rather than the 5W
  • hazyIPA wrote: »
    Doh! Good catch! How's this list looking now?
    I noticed a couple things I had overlooked...
    1. 2.5 ohm resister - 2.5 Ohm Vishay Mills 12 watt MRA-12
    2. 34 uF capacitor - Gen I Sonicap 34 uF 200VDC
    3. 2.7 ohm resister – 2.7 Ohm Vishay Mills 12 watt MRA-12
    4. Inductor – Keep Original
    5. 12 uF capacitor – Gen I Sonicap 12 uF 200VDC
    6. 34 12 uF capacitor – same as #2 same as #5
    Oof! If that list is right, that's >$250 in parts for the 2 speakers.
  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    Ha ha welcome to my nightmare as well lol! I love these speakers and get tremendous enjoyment from them though!

    @F1nut Those cardas binding posts are beauties no doubt and I really do want to stick to copper base metal, whether plated or not. I found these obvious made in China deals on amazon. Whadya think? They are short and I like the set screw, in addition to being solderable and they are pure copper conductor. All of these mfg's are pretty vague on details, especially the high end ones which gets frustrating. I mean am I to *assume* because it's Cardas that it is something like 4N copper or better....they don't say. I could use my Silclear silver platelet grease on the copper ones and maintain them every so often with the De-oxit.

    https://www.amazon.com/ZXHAO-Speaker-Amplifier-Terminal-Binding/dp/B07HYY1TQ1/ref=pd_sbs_23_2/140-6877126-1564253?_encoding=UTF8&pd_rd_i=B07HYY1TQ1&pd_rd_r=7c1bb6a6-b433-4955-9e9f-3ea09643f087&pd_rd_w=UB0Wn&pd_rd_wg=bLYX3&pf_rd_p=bdd201df-734f-454e-883c-73b0d8ccd4c3&pf_rd_r=07FJPX6SCBB7MZ357K34&psc=1&refRID=07FJPX6SCBB7MZ357K34

    0a23zfw8f5bp.png
    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
  • F1nut
    F1nut Posts: 49,707
    Roll of the dice, I would say.
    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

  • lmacmil
    lmacmil Posts: 119
    What's the rationale behind replacing the resistors? Is it because the original values may have drifted or is their some perceived sonic benefit with new or "better" resistors? I have 35 year old 7Bs that I need to re-cap (at least.) Not sure why I need to do resistors if they are still within the tolerance of their nominal values.
  • Gardenstater
    Gardenstater Posts: 4,136
    You can read here: https://www.hificollective.co.uk/components/mills.html

    "Mills Series Non-Inductive wirewound power resistors are very popular in audio, infinitely better than the ceramic "grey" type. An Aryton-Perry design with tinned copper leads, silver plated end caps. The core material is an alumina ceramic, providing significantly broader heat dissipation compared to that of normal steatite ceramic core. There are no magnetic materials used in these resistors. Applications include cathode resistors on valve output stages, power supplies, valve anode resistors and in speaker crossover networks. We stock MRA12, 12W range and the MRA05, 5W range. Please note it is sonically better to use a higher power resistor due to increased surface area. Tolerance is 5%."

    and here:

    "Non-magnetic, non-inductive, all welded construction
    greatly enhances frequency response. Combined with
    Aryton-Perry winding inductive reactance and signal
    loss are almost totally eliminated.
    Meets or exceeds the specifications in MIL-PRF-26
    for wirewound resistors.
    Meets the applicable specifications of MIL-STD-202,
    method 208
    Core: Alumina ceramic. This material
    provides significantly broader heat
    dissipation compared to that of
    normal steatite ceramic core.
    Element: Nickel-chromium or nickel-copper
    alloys used.
    Leads: Tinned Copper with Silver-plated
    endcaps."

    https://hfc-fs.s3-eu-west-1.amazonaws.com/s3fs-public/mills_data_0.pdf


    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
  • Viking64
    Viking64 Posts: 6,646
    RESIST NOT THE RESISTORS!!!!
  • Faustin
    Faustin Posts: 1,149
    In regards to replacing the resistors.............for the price of them, why wouldn't you? If you are going to replace the old, past their life caps, do the resistors as well. At the very least you know that everything is up to spec.
  • lmacmil
    lmacmil Posts: 119
    Faustin wrote: »
    In regards to replacing the resistors.............for the price of them, why wouldn't you? If you are going to replace the old, past their life caps, do the resistors as well. At the very least you know that everything is up to spec.

    And that's the best reason I've heard!
  • Navy_Goat
    Navy_Goat Posts: 375
    You could save a little coin by using some cheaper alternative caps in the lower frequency side of the crossover. You would need a schematic or someone to point ou the cap (caps?) which are in that side of the circuit. This hobby is like most others, the sky is the limit with most projects, but you can find cheaper alternatives which will not disappoint. Some research should lead you to more options. The members here are super knowledgeable and most are willing to help us newbs along. Good Luck with the project. Regardless of what you choose you will not be disappointed once everything is back together.
    SDA SRS 2.3tl, SDA 1C, SDA 2B (TL mod), Reserve 200
  • tonyp063
    tonyp063 Posts: 1,044
    If you go with Clarity CSA you will save about $30/crossover. They are the other well considered cap for vintage Polks.

    I have used them and I like them.
  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    I wasn't going to post this but here goes......this guy actually tested and reviewed tons of different capacitors and gave them relative ratings on a chart with the highest coming in at around 15 on a 0 to 20 scale, as well as gave his preferred ones! Must've cost him a fortune!

    http://www.humblehomemadehifi.com/Cap.html

    Sonic Craft Sonicap GEN-I MKP 220VDC - 5% tolerance

    Sound: Compared to a standard Mundorf M-Cap they are more transparent and clearer with lots more depth. Putting a 0,01uF Vishay MKP1837 parallel to them (a good tweak for nearly any capacitor) can create even more detail and separation! They reveal micro-information in a way that reminds me of a Hovland Musicap but without the Hovland loudness effect. I didn't find them to mix well with other caps - a 50/50 mix with a standard Mundorf M-Cap gave me the funny sensation of listening to two different cap's at the same time. I can advise them if you are looking for a high-end cap but are on a relatively tight budget. Quite nice :-)

    Verdict: 8,5

    Clarity Cap CSA MKP 250VDC and 630VDC - 5% tolerance

    Sound: The tonal character of the Clarity Cap CSA has in common with all Clarity Cap capacitors that is well balanced and never fatiguing. The CSA shows a pleasent intimacy combining the clarity (pun intended) of the ESA with the smoothness of the larger MR. Relatively speaking, I actually found the step up in sound quality from the ESA to the CSA to be greater than from an MR to a CMR. Both the CSA and CMR use Clarity Cap's Copper Connect Technology but it seems to have a greater effect on the SA range than of the MR range. Maybe it's easier to improve lower down the scale than further up it, I don't know, but that is how it cames across to me. Anyway, in direct comparison to the CSA the ESA sounds a little rougher, the CSA seems to produce a more civilized image that is at the same time more neutral. "S" and "T" sounds that were first maybe a little bit rough around the edges with the ESA (I am being very nit-picky here) become free from grain with the CSA. I also found the CSA to mix extremely well with the Jantzen Audio Alumen Z-Cap. A mix of a minimum of 20% Alumen Z-Cap with the rest Clarity Cap CSA enhanced realism of space and lushness of tone. They blend together seamlessly. All in all the Clarity Cap CSA is a well balanced, neutral capacitor that is a welcome addition to capacitors in the lower price range.

    Verdict: 9

    PS: you could save about $70 by going all ClarityCap CSA vs Sonicap Gen1, but I can only find a 33uF for ClarityCap vs 34uF desired. Having said that, I have already ordered Sonicap Gen1's for my crossovers so I hope they are better :smile:
    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
  • Gardenstater
    Gardenstater Posts: 4,136
    These ones are very high end apparently, and I see that a 12uF costs around $54 vs $28 for Sonicap Gen 1 and $18 for ClarityCap CSA. So we are going the wrong direction clearly with this choice.

    Jantzen Audio Superior Z-Cap 800VDC - 2% tolerance

    Technical specifications (according to manufacturer): "Double foil super PP capacitor featuring extremely high quality German made foil, metalized with aluminum and zinc particles. Featuring terminal leads made from PCOCC copper (oxygen free). Nitrogen filled instead of dielectric fluid, offering more foil per capacitor and eliminating risk of evaporation. Voltage rating 0,10uF - 0,33uF: 1200VDC or 600VAC, Voltage rating 0,47uF - 22uF: 800VDC or 425VAC, Non inductive construction, Terminal leads are made from Pure Copper Ohno Continuous Cast Wire (oxygen free), Capacitance tolerance : +/- 2%, Voltage rating: 800 - 1200VDC, Loss factor: 1K 0.00002 10K 0.00001, Non-polarized capacitor".

    Sound: Very neutral and coherent balance, they don't seem to high-light anything and I mean that in a positive way! They are a little flatter in presentation than their more expensive brother, the Silver Z-Cap but still better than the Clarity Cap ESA in depth and spatial information. In direct comparison with a Clarity Cap ESA they are less up-front in the lower treble and have a better texturing of acoustic instruments like a violin for example. In the upper treble they are slightly clearer than a Mundorf Supreme Silver/Gold which probably explains the good spatial information and separation. Compared to the Jantzen Audio Silver Z-Cap I find them the more musical of the two. The Jantzen Audio Superior Z-Cap is a no-brainer if you are looking for a capacitor that performs well in all area's and is very well balanced. One of my personal allround favourites :-)

    Verdict: 10+
    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
  • mhardy6647
    mhardy6647 Posts: 32,926

    0a23zfw8f5bp.png
    F1nut wrote: »
    Roll of the dice, I would say.

    One tends to get what one pays for. :|

  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    @mhardy6647 Aargh I know I know, but they say it is pure copper conductor and it's just a binding post with threaded components right? It's awful tempting to pay $18 for these vs $94 for the Cardas, which doesn't even have the set screw.

    I'm looking at the Chinese ones and it sure does look like it's gold plated (or worst case brass lol), I mean does that look like copper? Sent them a question asking same.

    I think it's pretty hard to verify whether something is made out of copper or brass unless you can weigh the under water and above water maybe to calc. the density. Could be lots of fake copper binding posts out there. Another way would be with a hardness tester because I think most certainly copper is softer than brass. Decisions decisions :s

    PS: Perhaps I will get the Chinese ones from Amazon and if I can scratch a pre 1984 copper penny with the sharp end of the binding post, I will assume it's brass and demand money back from Amazon (sounds like a plan lol)
    Post edited by Gardenstater on
    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
  • F1nut
    F1nut Posts: 49,707
    George, most of us here are very familiar with Tony Gee's capacitor site.

    As you noted with the Clarity caps, most of the choices out there do not have the exact values required for Polk crossovers. Jeff, the owner of Sonic Craft/Sonicap made sure to offer caps in the exact values we need, which is fortunate because Sonicaps work extremely well with vintage Polk speakers.
    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