Polks SDA 2B TL mod

keck
keck Posts: 36
edited January 2020 in Vintage Speakers
Dear all, its been a couple of year since i own a pair of 10A and SDA 2B. I have done the recapped on my 10A previously and it sounds really great. Currently i am planning to do the SDA 2B TL mod. Would like to have any advice from anyone :smile:

Below are the parts i plan to purchase:
A pair of Gimpod boards
For High pass:
2 x 2.7 Ohm Vishay Mills MRA-12
2 x Gen I Sonicap 12 uF 200VDC
2 x Gen I Sonicap 5.8 uF 200VDC
2 x 0.22 Ohm Vishay Mills MRA-12
For Low pass:
2 x Clarity PX 20uf
2 x Clarity PX 40uf

I really wanted to go with all Sonicap, but is way over my budget.... :'(

Any other recommendation for other Low pass cap or should i stick with Dayton cap just like i did for my 10A crossover?
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Comments

  • Gardenstater
    Gardenstater Posts: 4,136
    I don't get the impression that Dayton's are all that well thought of by folks here. Your list shows you going with Clarity caps for the low pass though so I'm confused......
    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
  • keck
    keck Posts: 36
    My previous Monitor 10 recap was a mixture of Sonicap and Dayton. IIRC, the idea was from some passed thread, so i proceed with the recapp. Removed the fuse block and replaced binding post.

    6hgac3gmzydx.jpg


    Now planning in doing the 2B TL mod. Just curios if the selection of parts as mentioned above are ok? Athough i understand Sonicap is always the recommended cap.
  • Gardenstater
    Gardenstater Posts: 4,136
    Hopefully someone with experience will chime in, which is not me. I'm wondering what people think of the Erse Pulse X Polypropylene caps here: http://www.erseaudio.com/Products/PulseX
    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
    I don't see Clarity PX in 20uf or 40 uf here: http://www.claritycap.co.uk/products/px.php
    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
  • keck
    keck Posts: 36
    edited January 2020
    I don't see Clarity PX in 20uf or 40 uf here: http://www.claritycap.co.uk/products/px.php

    I found them in PartsConnextion
    xf2nsdj9vfzf.jpg
    anonymouse wrote: »
    I have been happy with Dayton on the low side. I have not done a set with Sonicaps on the low side though.

    Great to hear that. I was initially plan to use Dayton, but after reading the threads, some were saying to go for Clarity PX which is just a little more price differences 😀
  • pitdogg2
    pitdogg2 Posts: 24,478
    Yea I'd take Clarity over Dayton or Erse.
  • keck
    keck Posts: 36
    Thanks, i will probably go with Clarity PX.
    Also, is there any recommendation on the binding post other than Cardas CCGR L. Should i replace all the internal wiring?
  • westmassguy
    westmassguy Posts: 6,850
    Not sure where you're from @keck, but Madisound carries Clarity PX. You might want to consider 2 X 20uf instead of the 40uf, whether you're using the existing boards, or Tony's. If you want the Cardas posts, try Soniccraft (for Mills resistors too). I use the Cardas CCGG S posts on many of my builds.
    Home Theater/2 Channel:
    Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
    Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
    Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
    Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
    Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer

    dhsspeakerservice.com/
  • hauxon
    hauxon Posts: 161
    40uF caps in SDA 2B? You need six 20uF caps for the 2B low frequency part. You can see schematics and parts list in the Gimpod site (http://www.gimpod.com/parts2b.html).

    If you you want to keep the budget as tight as possible I think it is a good decision to buy better caps for the HF like you're planning. You could skip the Gimpods and buy Sonicaps for the LF, it would be harder to fit but possible. ..or just accept the added $10 more for each of the 20uF caps, not that much really. A TL modded 2B is a great sounding speaker an I dare to say it would be hard to find a better sounding modern speaker on this side of $2000. So an extra $60 is totally justifiable to me.

    I have TL modded 2B's in my home office/man cave and used ClarityCap ESA for the HF. I still haven't recapped the LF but plan on using ClarityCaps there too. The ESA sound great and the CSA too (used in my SRS 1.2TL).

    Hrannar
    SRS 1.2 TL | SDA 2B Studio TL | NAD M51 preamp/dac | DIY SET 300B tube amplifier | Cambridge Audio Azur 851W | Chromecast Audio | RoPieee Roon Raspberry Pi endpoint
  • K_M
    K_M Posts: 1,627
    I don't get the impression that Dayton's are all that well thought of by folks here. Your list shows you going with Clarity caps for the low pass though so I'm confused......

    Have used them before, and outside this forum, they are well thought of.
    DIY forums view this stuff FAR differently by the way.
  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    keck wrote: »
    Thanks, i will probably go with Clarity PX.
    Also, is there any recommendation on the binding post other than Cardas CCGR L. Should i replace all the internal wiring?

    I bookmarked this thread where someone (thanks gmcman) re-wired their 2.3TLs and reported outstanding results. I'm going to do this to my 7B's sometime, which should be much easier: https://forum.polkaudio.com/discussion/182947/cardas-litz-internal-re-wire-for-2-3tl#latest
    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
  • keck
    keck Posts: 36
    anonymouse wrote: »
    TBH, the binding posts and wiring are nowhere as much of an improvement as the caps and resistors, but they do give you the mental satisfaction that its all done. Use silver solder too. I've found Larry's rings and dynamat on the baskets are important.

    Thanks. Probably will go with the dynamat as well. Also where can i get the Larry's rig if i decided to install it?
    Not sure where you're from @keck, but Madisound carries Clarity PX. You might want to consider 2 X 20uf instead of the 40uf, whether you're using the existing boards, or Tony's. If you want the Cardas posts, try Soniccraft (for Mills resistors too). I use the Cardas CCGG S posts on many of my builds.

    Thanks West, i will go with 2 x 20uf instead. Just curious what is the difference in using 1 x 40uf?
    hauxon wrote: »
    40uF caps in SDA 2B? You need six 20uF caps for the 2B low frequency part. You can see schematics and parts list in the Gimpod site (http://www.gimpod.com/parts2b.html).

    If you you want to keep the budget as tight as possible I think it is a good decision to buy better caps for the HF like you're planning. You could skip the Gimpods and buy Sonicaps for the LF, it would be harder to fit but possible. ..or just accept the added $10 more for each of the 20uF caps, not that much really. A TL modded 2B is a great sounding speaker an I dare to say it would be hard to find a better sounding modern speaker on this side of $2000. So an extra $60 is totally justifiable to me.

    I have TL modded 2B's in my home office/man cave and used ClarityCap ESA for the HF. I still haven't recapped the LF but plan on using ClarityCaps there too. The ESA sound great and the CSA too (used in my SRS 1.2TL).

    Hrannar

    6 x 20uf Sonicap - $238.80
    6 x 20uf Clarity PX - $91.86
    I will probably go for Clarity. I was shock to see the price of Sonicap has went up quite a bit since my last purchase for M10 recap.
  • Larrys Rings are just a myth. Buy and install h nuts instead.
  • keck
    keck Posts: 36
    Larrys Rings are just a myth. Buy and install h nuts instead.

    Is this the correct size from partsexpress
    https://www.parts-express.com/parts-express-8-32-hurricane-nuts-50-pcs--081-1080

    With the H nut, should i replace the gasket with ArmaFlex Insulation Tape, or should i just leave the original gasket as it is, if they are not broken.
  • Gardenstater
    Gardenstater Posts: 4,136
    Larrys Rings are just a myth. Buy and install h nuts instead.

    I wonder about the Larrys Rings. If the material is thin comprising the ring, I'm not sure how much stiffness it adds relative to just the particle board alone. Also, another thing I've wondered about is whether or not some sonic advantage could be made by rounding over the inside edge where the woofers mount to decrease diffraction effects that might be caused by the sharp edge there. Larrys Rings would defeat this modification. The hurricane nuts could probably still be used if you did this and maybe epoxying them in also would be wise.

    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
  • K_M
    K_M Posts: 1,627
    edited January 2020
    Larrys Rings are just a myth. Buy and install h nuts instead.

    I wonder about the Larrys Rings. If the material is thin comprising the ring, I'm not sure how much stiffness it adds relative to just the particle board alone. Also, another thing I've wondered about is whether or not some sonic advantage could be made by rounding over the inside edge where the woofers mount to decrease diffraction effects that might be caused by the sharp edge there. Larrys Rings would defeat this modification. The hurricane nuts could probably still be used if you did this and maybe epoxying them in also would be wise.

    rounding over is good in theory, but the particle board used by Polk back in the day, crumbled fairly easily, and was not all that "Workable" overall, compared to Better types of MDF or actual wood.

    Not sure if it was the glue or binders or the particle size, but just not cleanly routed.
  • Gardenstater
    Gardenstater Posts: 4,136
    K_M wrote: »

    rounding over is good in theory, but the particle board used by Polk back in the day, crumbled fairly easily, and was not all that "Workable" overall, compared to Better types of MDF or actual wood.

    Not sure if it was the glue or binders or the particle size, but just not cleanly routed.

    I think some clear penetrating epoxy applied to the roundover area to consolidate the flaky particle board might take care of things, along with epoxying in the hurricane nuts. I'd most definitely use a brand new roundover bit, with a top bearing rather than the usual bottom bearing.

    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
  • polrbehr
    polrbehr Posts: 2,825
    K_M wrote: »
    I don't get the impression that Dayton's are all that well thought of by folks here. Your list shows you going with Clarity caps for the low pass though so I'm confused......

    Have used them before, and outside this forum, they are well thought of.
    DIY forums view this stuff FAR differently by the way.

    Well when you consider that outside of this forum (and even by some people inside this forum), SDAs are often considered a joke, it isn't too surprising that anything that upgrades them would be well received either.

    I think the mindset is, if you're going to redo the crossovers, you might as well get higher end components and be done with it.
    Larrys Rings are just a myth. Buy and install h nuts instead.

    Why do you say that?

    So, are you willing to put forth a little effort or are you happy sitting in your skeptical poo pile?


    http://audiomilitia.proboards.com/
  • westmassguy
    westmassguy Posts: 6,850
    Larrys Rings are just a myth. Buy and install h nuts instead.

    They're not a myth, @Toolfan66 has a life outside this forum. If and when he does another run, I'm sure he'll let us all know.
    Home Theater/2 Channel:
    Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
    Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
    Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
    Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
    Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer

    dhsspeakerservice.com/
  • westmassguy
    westmassguy Posts: 6,850
    @keck The Clarity caps are huge compared to other brands. @gimpod designed the boards with Sonicaps in mind. You can go with a single 40uf, but the board has provisions for 2 X 20 for the low pass shunt on the dimensional side. It's a neater looking job IMHO.
    Also, if you go Cardas, don't get the Cardas CCGR "L", get the "S"
    If you're reusing the OEM binding post cups, they're only 1/8" thick plastic
    Home Theater/2 Channel:
    Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
    Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
    Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
    Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
    Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer

    dhsspeakerservice.com/
  • keck
    keck Posts: 36
    Thanks West, i get it now. The 2 x 20uf is prefer over 1 x 40uf when use in Gimpods board. If using back the original board, either 2 x 20uf or 1x 40uf are fine.

    So i have decided to go with the b/m parts
    A pair of Gimpod boards
    For High pass:
    2 x 2.7 Ohm Vishay Mills MRA-12
    2 x Gen I Sonicap 12 uF 200VDC
    2 x Gen I Sonicap 5.8 uF 200VDC
    2 x 0.22 Ohm Vishay Mills MRA-12
    For Low pass:
    6 x Clarity PX 20uf

    As for binding post, should i go with Cardas CCR-S for $72(2 pairs) or just get a cheaper alternative from partsexpress. Will the binding post makes the sound difference? Anyone has experience to share with regards to binding post?
  • F1nut
    F1nut Posts: 49,709
    2 x 0.22 Ohm Vishay Mills MRA-12

    That should be 2 x 0.5 ohm.


    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

  • F1nut
    F1nut Posts: 49,709
    Larrys Rings are just a myth. Buy and install h nuts instead.

    I wonder about the Larrys Rings. If the material is thin comprising the ring, I'm not sure how much stiffness it adds relative to just the particle board alone. Also, another thing I've wondered about is whether or not some sonic advantage could be made by rounding over the inside edge where the woofers mount to decrease diffraction effects that might be caused by the sharp edge there. Larrys Rings would defeat this modification. The hurricane nuts could probably still be used if you did this and maybe epoxying them in also would be wise.

    Rounding over the driver cut outs is a complete waste of time as the basket edge is just about flush with the bezel.

    Don't wonder about Larry's rings, they are proven to work exactly as designed. They clamp the basket to the bezel.

    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

  • keck
    keck Posts: 36
    F1nut wrote: »
    2 x 0.22 Ohm Vishay Mills MRA-12

    That should be 2 x 0.5 ohm.


    Noted, thanks F1 for pointing out.
  • Gardenstater
    Gardenstater Posts: 4,136
    edited January 2020
    @F1nut said:
    Rounding over the driver cut outs is a complete waste of time as the basket edge is just about flush with the bezel.

    Appreciate your response. I just feel that rounding over the bezel should only serve to increase the air flow into and out of the 4 cutouts in the midwoofer baskets, and should make that airflow more smooth and laminar as well.

    @F1nut said:
    Don't wonder about Larry's rings, they are proven to work exactly as designed. They clamp the basket to the bezel.


    Thanks. Does it actually allow more torque to be applied to the mounting screws? I think the torque is limited by how stiff the basket lip is as well as the surface area of the screw head and relative thinness of the basket metal and also the desire to not oversquash the sealing gasket.

    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: 49,709
    There is a 2mm difference between the edge of the metal basket frame and the edge of the bezel. Rounding off the bezel edge will not make any sort of sound difference. However, it will make a mess of the bezel.

    Larry's rings create a sandwich effect, metal/*MDF or particleboard/metal. This allows the basket to become one with the bezel. The gasket should be paper thin as anything thicker defeats the purpose of the rings.

    *The 4th and 5th generation bezels are MDF.
    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

  • boston1450
    boston1450 Posts: 7,438
    Larrys Rings are just a myth. Buy and install h nuts instead.

    I take it you mean hard to get. It may happen thanks to Larry. Question = Have you installed these in any speakers yet ? I have used hurricane nuts on many speaker cabinets including Polk speakers & YES they work. Larry's rings I have installed 3 or 4 sets of them Crs+ 1c RTA15tl & 2b speaker cabinets & they are made well. If you install them you would know they have no choice but to be far better. Take a MW driver with 4 screw holes & put 4 hurricane nuts VS a complete ring you slide where the screw holes were. Snug as a bug. No slipping here :)
    ..
    ..
    ..
    Randy/Maine
  • boston1450
    boston1450 Posts: 7,438
    keck wrote: »
    Larrys Rings are just a myth. Buy and install h nuts instead.

    Is this the correct size from partsexpress
    https://www.parts-express.com/parts-express-8-32-hurricane-nuts-50-pcs--081-1080

    With the H nut, should i replace the gasket with ArmaFlex Insulation Tape, or should i just leave the original gasket as it is, if they are not broken.

    If the original gasket looks ok = reuse it.... If it has any wear or cut/slices on it = replace it. Usually they are reusable.... Not sure it was mentioned but fine time to glue your magnets & dynamate your baskets. Good luck
    ..
    ..
    ..
    Randy/Maine
  • boston1450
    boston1450 Posts: 7,438
    K_M wrote: »
    I don't get the impression that Dayton's are all that well thought of by folks here. Your list shows you going with Clarity caps for the low pass though so I'm confused......

    Have used them before, and outside this forum, they are well thought of.
    DIY forums view this stuff FAR differently by the way.

    Do you feel alone ? Lmao. I thought I post useless post & I do. But read this a few times & all I can do is scratch my head
    ..
    ..
    ..
    Randy/Maine
  • keck
    keck Posts: 36
    Hi all, as for binding post, should i go with Cardas CCR-S for $72(2 pairs) or just get a cheaper alternative from partsexpress. Will the binding post makes noticeable differences? Anyone has experience to share with regards to binding post?