Upgrade my Polk 5jr+

Bigbang
Bigbang Posts: 233
edited June 2009 in Vintage Speakers
Club Polk,

I want to start small so here goes...

I have some big honking SRS's that I will eventually upgrade but I also have some Polk 5jr+'s that I have laying around that sound great. I'd like to modify them and since there is not much circuitry and I'm decent with an iron, I thought I would start with those. Here is what I think I want to do but please add your suggestions. Also, I'm a little new so you might have to really spell it out for me.

I have attached some pics...

1. replace the caps and resistors.
2. upgrade the terminals.
3. decide if I want to replace or get rid of the polys. They have saved me a few times.
4. consider replacing the tweeters if I can?
5. anything else to consider?

Any help would be appreciated.

David
I like to listen, tinker, listen and repeat.
5jr.jpg 104.3K
5jr2.jpg 118.6K
Post edited by Bigbang on

Comments

  • McLoki
    McLoki Posts: 5,231
    edited May 2009
    Sonicap is the performance leader for a moderate price. (percentage wise)

    Dayton (from parts express) has a very strong following at a very low cost.

    Mills (or I think the other recommendation was mundorf) for the resistors.

    You don't mention what tweeter you have in your 5jr's. If SL1000 or SL2000 - definately replace. If sl2500 or Pearless - I would keep them at least until you get the crossovers upgraded and decide if you need more.

    I assume you have the schematic. (it is available here on Club Polk)

    Other than that - take lots of pics and post back often with your project impressions and results.

    Michael
    Mains.............Polk LSi15 (Cherry)
    Center............Polk LSiC (Crossover upgraded)
    Surrounds.......Polk LSi7 (Gloss Black - wood sides removed and crossovers upgraded)
    Subwoofers.....SVS 25-31 CS+ and PC+ (both 20hz tune)
    Pre\Pro...........NAD T163 (Modded with LM4562 opamps)
    Amplifier.........Cinepro 3k6 (6-channel, 500wpc@4ohms)
  • Bigbang
    Bigbang Posts: 233
    edited May 2009
    McLoki,

    Thanks for the input. Can I assume that the blue cylindrycal object is the cap? Is this what I would replace with Sonicap/Dayton? Also is the rectangular white object the resistor that I would replace with the Mills/Mundorf? I'm a visual guy. Not very good with schematics but yes, thanks, I've got it.

    Should I replace the Polyswitches?

    I have the sl2000 tweets.

    Thanks David
    I like to listen, tinker, listen and repeat.
  • nduitch
    nduitch Posts: 316
    edited May 2009
    Bigbang wrote: »
    McLoki,

    Thanks for the input. Can I assume that the blue cylindrycal object is the cap? Is this what I would replace with Sonicap/Dayton? Also is the rectangular white object the resistor that I would replace with the Mills/Mundorf? I'm a visual guy. Not very good with schematics but yes, thanks, I've got it.

    Should I replace the Polyswitches?

    I have the sl2000 tweets.

    Thanks David

    Yes blue is the cap. You can replace it with whatever you want, depends on how much money you want to spend really. I have replaced monitor 7's with dayton and was pleased. I spent a little more money on my SDA to replace them with sonicaps on the tweets, so far after about 20 hours they are sounding really nice. So if you have the money to spend or if you want them to sound a little better, buy the sonicaps. White is resistor. You can also replace if you feel this will further improve sound quality. Poly switches can be removed if you feel they color the sound. Or leave them in if you have random kids messing with your gear.
  • Bigbang
    Bigbang Posts: 233
    edited June 2009
    Today I upgraded the crossover on my little Polk 5jr+ speakers. It is a simple matter to most but I wanted to give it a try before tackling my SDA SRS’s. There were three components on the crossover I decided to replace. This was by no means a very serious venture but I wanted the practice and wanted to see if I could hear the difference.

    First, the Capacitor. I consider this to be the most important upgrade from what I’ve read so I felt it needed to be replaced. I decided to use the Solen 12uF to replace the stock cap. It was quite a bit larger and had to be positioned on the back of the terminal board. The stock cap was a 12uF 50v and I replaced it with a Solen 12uF 400v. I’m really not sure what implications voltage has but it was what they had.

    Second I replaced the stock resistor with a Mills resistor. Some people say this has little bearing on the sound but I thought what the hell… While I’m in there…

    Lastly I replaced the Polypropylene. Most of you would say I should have just removed it and placed a jumper on it but again, I figured while I’m in there and it has saved my tweeter a couple of times… Plus I can always go back in and remove it.

    While I was in there I replaced the speaker bindings. Just some generic gold plated Dayton’s.

    I really have to say it was worth it. It took me a couple of hours but the difference in sound is very noticeable, even to my very modest ears. The highs have a more crisp natural sound and the bass has a tighter feel. These are now the speakers I remembered when I purchased them in 1989. I would recommend the upgrade even though it was just a pair of 5jr+’s.

    All for about 25 bucks for crossover parts. 11 bucks for the new binding posts and 10 bucks for shipping.

    Now on to the monoliths…

    David
    I like to listen, tinker, listen and repeat.
  • heiney9
    heiney9 Posts: 25,053
    edited June 2009
    Nice work! Wait until they break-in you're in for a treat. Do the tweets if you haven't already that's just as rewarding.

    I used Solens and Mills in my 5B's and felt it was a good compromise to pricier caps. My SDA's have Sonicaps and in that application they are worth every penny
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Pangea AC14SE MKII | Legend L600 | BlueSound Node 3 - Tubes add soul!
  • Bigbang
    Bigbang Posts: 233
    edited June 2009
    Thanks H9,

    Did you replace the tweets with the 194's?

    d
    I like to listen, tinker, listen and repeat.