Differences in Crossover upgrade options for SDA SRS 2s (Blade/Blade)

Karn

Hey everyone,

Before I ask my questions, I wanted to preface that I read through two pages of searches here on the site for the information I was looking for, and specifically read these links:

https://forum.polkaudio.com/discussion/27025/sda-srs-rebuild-my-crossovers?utm_source=community-search&utm_medium=organic-search&utm_term=SDA+SRS+2+crossover+rebuild

https://forum.polkaudio.com/discussion/74946/sda-srs-2-crossover-parts-list/p3

https://forum.polkaudio.com/discussion/78812/i-would-like-to-tl-my-1986-sda-srs-2s?utm_source=community-search&utm_medium=organic-search&utm_term=SDA+SRS+2+crossover+rebuild

https://forum.polkaudio.com/discussion/48222/sda-srs-srs-1-2-srs-1-2tl-srs-2-3tl-crossover-design-and-progressive-point-source?utm_source=community-search&utm_medium=organic-search&utm_term=SDA+SRS+2+crossover+rebuild

https://forum.polkaudio.com/discussion/161991/calling-all-sda-srs-2-srs-2-3-srs-2-3tl-owners?utm_source=community-search&utm_medium=organic-search&utm_term=SDA+SRS+2+crossover+rebuild

https://forum.polkaudio.com/discussion/133384/all-the-polk-sda-upgrades-located-in-one-place/p2

I did not find the answer to the specific question I am looking for so I posted here. Apologies if it has been answered elsewhere, I just did not find it.

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I am currently running ~1986 SDA SRS 2's (Blade/Blade) w/RD0194s. At this time I do not desire to switch to the tweeters to RD0198s ('ve read that other users have attempted/succeeded in doing so however).

I have all matching MW6509 woofers installed w/ the stock SW150 PRs.

I know the crossovers are original and due for a refresh, as I have been inside the enclosure for inspections, cleaning and replacement of incorrect woofers and tweeters and PR repair.

I notice that there are handful of premade options for "upgrades" to the crossovers, ranging from $600 to $2000. I notice the component topology is quite different between the various "upgrade" options. Some of the more expensive options obviously have some extreme modifications being performed -and I don't know why/to what benefit

My question is this. Assuming I want to keep my drivers and tweeters stock, what are the benefits, if any, to changing crossover topologies versus just a simple re-cap and resistor/inductor swap-out (which I can do myself)?

I also read mention of a user who posted a step-by-step refresh/rebuild/upgrade process, named Raife(?), but I could not find this information -when I checked the VR3mod user's sticky, the links were either dead or the images/websites were no longer hosted.

Thank you everyone.

Karn

Edit - update (couldn't update original post)

I managed to find:

https://www.vr3mods.net/polk-sda-updates-information

and this:

https://forum.polkaudio.com/discussion/55888/polk-audio-speaker-wiring-schematics-more-stereo-dimensional-array-sda#latest

Wonderful website resources, however, I'm still curious as to what the modern crossover upgrade options exist to offer.

F1nut

I notice that there are handful of premade options for "upgrades" to the crossovers, ranging from $600 to $2000. I notice the component topology is quite different between the various "upgrade" options. Some of the more expensive options obviously have some extreme modifications being performed -and I don't know why/to what benefit

Please provide links/exact info of each otherwise your question cannot be answered.

FYI, in the links you provided ignore anything suggested by Ben.

Karn

F1nut wrote: »

I notice that there are handful of premade options for "upgrades" to the crossovers, ranging from $600 to $2000. I notice the component topology is quite different between the various "upgrade" options. Some of the more expensive options obviously have some extreme modifications being performed -and I don't know why/to what benefit

Please provide links/exact info of each otherwise your question cannot be answered.

FYI, in the links you provided ignore anything suggested by Ben.

Good point, sorry I missed that.

More expensive option:

https://www.vr3mods.net/product-page/polk-audio-sda-srs-2-1987-linh-series-crossover-build

The second option is no longer available from the seller via ebay, and their website does not show past work, so unfortunately this example is null but here is the seller in case anyone recalls their work:

https://www.ebay.com/sch/i.html?_dkr=1&iconV2Request=true&_blrs=recall_filtering&_ssn=crossoverchef-com&_oac=1&_nkw=sda

Attached are some images of my stock crossover. I also notice that the VR3mod version states for "1987" revision.. concerned this would not work for the Blade/Blade 1986(?) variant I have.

pitdogg2

The RD-0194 is the only option you have. There was no sanctioned Polk upgrade to use the RD-0198 tweeters in the blade/Blade or Pin/blade. It was talked about but to my knowledge none that Polk sanctioned.
Your best bet is to replace all caps, resistors and inductors.
Jantzen air-core perfect lay inductors is what most of us used in our rebuilds.
With good quality poly caps and resistors (not sandcast or ceramic)you can take them to the next level.
Most have used Sonicaps and Clarity caps. Resistors have been replaced with 10 or 12 watt Vishay-Mills, Jantzen or Mundorf.

Karn

Thanks for that info pitdogg2.

I also notice in the upgraded crossovers there's a higher amount of inductors. Can anyone explain what these are doing for the crossovers versus the stock amount/size inductors? Also notice the VR3mod in particular has what appears to be parallel caps or at least stacked caps. If they are parallel, is this done to get equivalent modern values?

F1nut

You can ask Trey (VR3) your questions about his work either through his site or here.

I can say the 2 crossover versions are very different, so yours does not look like the 1987 version.

The eBay guy...those are a joke.

VR3

The last post here is my latest 1986 build

https://forum.polkaudio.com/discussion/141740/polk-audio-sda-srs-2-crossover-modification-thread/p2