Wanting to upgrade Polk RTi-150 crossovers, but how far to take it?

A number of years ago I replaced the small value caps with Dayton poly caps and the others with electrolytic caps, real budget job. Since then I’ve been pleased with their sound and felt they sounded better then newer/higher end speakers. Then I picked up another pair and was quite disappointed with the sound, until I realized it must be the crossover making the difference. So now I want to do a better job on the second set and see where that takes them, but the cost is prohibitive. The mid woofer uses a 400 uF cap and the woofers use a 130 uF, going with basic Solen poly caps will run $466.52 just for these two, total cost in the $700-800 range going for very mid range parts. What are your thoughts?

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2 x all the items below:
Caps: 2x 0.47 uF, 8.0uF, 18uF, 130 uF, 400 uF
Inductors: 0.2 mF, 1.2 mF, 2.0 mF
Resistors: 2x 1.5 Ohm, 5.7 Ohm
- Wes
Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10

Best Answers

  • treitz3
    treitz3 Posts: 18,230
    Answer ✓
    Member since 2005 and only 3 posts? You are gonna have to ease it up on the posting man! :*

    Here are my thoughts. I have a set of Tyler Acoustic speakers that the crossover upgrades cost about what the speakers did. Just the parts for the crossovers, that is.

    I would pay no mind to the cost of the upgrade versus the cost of the speakers. I have heard $10.00 speakers (found on Craigslist by a buddy of mine) that had crossover upgrades into the multiple hundreds of dollars, pushing the 1K territory.

    Just speaking on these two speakers? To me (and to my buddy), the upgrades were more than worth the time, effort and cost put into them. The sonic differences simply brought them to the next level.

    Is it worth it to you? Only you can answer that. You already have experience with your first upgrade and you now know what an upgrade can do. My advice would be to do two things. Get what you can afford at this moment in time (upgrades to the upgrades can always be done in the future). Get only those upgrades that will actually fit in the cabinet without taking up too much internal volume, otherwise you will affect the sonic characteristics of the speakers.

    Oh....make sure that all of the cold solder joints are corrected/done correctly. ;)

    Tom
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • Emlyn
    Emlyn Posts: 4,346
    Answer ✓
    I had a couple pairs of RTi150 back in the day. I'm not certain, but I think they may have been the last product line that came out of the Mexico plant before Polk shifted production to China. Mine were swapped out for the RTiA9 thanks to Circuit City's trade in deals and then those were quickly replaced with a combination SDA-1C and LSi system. I tried the LSi15 as mains and also wasn't happy with their bass performance.

    I do remember the RTi150 would handle a lot of power and ran a Rotel RB-1090 with them to good effect. Fun speakers to rock out with but they did need a hefty amp to do that. $800 would only buy a pair of bookshelf speakers so it may be worthwhile to try upgrading the crossovers if you really like the sound of the RTi150s.

    The Reserve speakers would be a definite BIG upgrade over stock RTI150 and the Legend would look better cosmetically at a higher price.
  • pitdogg2
    pitdogg2 Posts: 24,481
    Answer ✓
    3m double sided adhesive tape for the caps works great. It comes in different strengths like 15lb and 30lb. You put some of that between the caps and on the bottom nothing moves and it also acts like a shock adsorber because of the thickness and its softness. I've used hot melt glue on caps (never resistors) in the past. I usually raise the resistors of the board to allow heat to dissipate better. One of our member years ago covered a couple of resistors, if my memory is correct they were double the wattage of the factory 5watts to 12 watts. They pictures of the resistors were very memorable for me. They looked like somewone had held a heat gun to them, scorched real bad. You may get lucky and have no problems, best practices would be better off keeping glue off them.

Answers

  • VR3
    VR3 Posts: 27,970
    So I am all for crossover upgrades. That series from Polk was one of the shortest run series in history, replaced in under 2 years. They simply didn't sound the best in their price class

    If it were me I would sell them and go to the Rtia9 if to wanted to stay with the rt series or go to the new reserve
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • westly197
    westly197 Posts: 13
    edited June 2022
    I know these speakers are rare, but I’ve wondered if it wasn’t how they were setup versus them not sounding as good? I’ve found they want power, you hook them up to a cheap receiver and not great. You hook them to a nice powerful amp and they sound amazing. I’ve not tried the A9, but I wondered if the RTi150 lack of popularity was not a combination of their old school look and need for a good amp versus being a sub par performer when properly implemented? I’ve compared them to my LSi15’s in their current state and everyone I asked thought the RTi150’s sounded better in my setup powering them off an ATI Signature 4002 dual mono amp. Was that because of the $50 crossover upgrade, possible, would love to hear more on if this model is a poor choice to upgrade versus just a misunderstood model.

    As far as only 3 posts, I don’t understand that, perhaps I had another login I forgot? I did lots of research back when I had the RT3000P’s and rebuilt both plate amps, but perhaps I found everything I needed, hard to say. I did minor crossover updates to several of my previous speakers, but always kept it on the low cost side. I recently upgraded the Magnepan LRS with better components and was blown away with the improvement, so started thinking perhaps it’s worth taking it a lot further. If I can make a $600 speaker sound close to a $3800 speaker with $260 in parts, perhaps I’ve been missing something…

    Every time I’ve sold speakers, I’ve compared them and these RTi150’s have won out every time, it’s the only reason I still have them. I recently sold my second pair of LSI15’s in favor of keeping these because they sounded better, could have been a mistake… perhaps the LSi’s would have won out with a few dollars in crossover upgrades. I was never crazy about the bass woofer in the LSi, the three woofers in the RTi 150 are fast and tight with good power.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • treitz3
    treitz3 Posts: 18,230
    Ah, as far as the post count goes? A few years back, the Polk forum switched from one software to Vanilla (the current software). During that switch, many log-ins were compromised, many posts were deleted and many users lost their post count.

    I was just razzin' ya', Wes. Post count means nothing to me, honestly. I just thought it was funny to have been a member for so long and only have 3 posts.

    IME, better parts means better quality sound.....but, just like everything.....cost does not necessarily equate to better sound. It's best to simply ask questions, be patient and rely on some folks who have direct experience with crossover upgrades. Many on this forum (as you know) have done upgrades in this department.

    You may want to entertain the thought of upgrading the wires themself as well.

    Tom
    ~ In search of accurate reproduction of music. Real sound is my reference and while perfection may not be attainable? If I chase it, I might just catch excellence. ~
  • VR3
    VR3 Posts: 27,970
    The entire line only lasted a little under two years.

    If you like them, definitely upgrade them. You can just bypass those large values and see gains
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • westly197
    westly197 Posts: 13
    edited June 2022
    I’d definitely consider looking for a different speaker to upgrade, I’ve even thought of building my own speakers from a kit - still debating if I want to get into that much work. I just would not want to move away from these if they are actually better, but just require more to be better. Sometimes harder to drive speakers are better than more efficient speakers when driven by sufficient power, but the masses will often favor the ones that sound better on low end equipment. The finish on these also doesn’t compare to the look of some of the ones that came after, though it’s probably a tad bit better material. I also had the impression the newer models had a cheaper look I was not crazy for, I skipped up to the LSi and do like the Polk Audio Reserve series more but have only heard the R900 I’m using for Atmos. I honestly don’t know, it’s why I’m posting here, don’t want to waste my money. These are used in a two channel system only, if that makes any difference.

    If I move forward with this XO upgrade, I will replace everything, new wires, complete new XO parts point to point twisted together and soldered, new connections removing all the ferris metal and tin, etc. I was going to use copper ribbon inductor on the tweeter and open air copper on the mid and bass. Solen for the high value caps and possibly sonicaps for the others. Possibly better for the bypass, but the cost was getting crazy so that’s when I hopped on here to reconsider. I was also going to break up the crossover into 2 - 3 parts as this speaker is heavily braced internally, so It would be easier to place a couple smaller XO’s and will allow the inductors to be far apart.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • westly197
    westly197 Posts: 13
    VR3 wrote: »
    So I am all for crossover upgrades. That series from Polk was one of the shortest run series in history, replaced in under 2 years. They simply didn't sound the best in their price class

    If it were me I would sell them and go to the Rtia9 if to wanted to stay with the rt series or go to the new reserve

    The only problem buying a new & current speaker set is the big cost for the speakers, which still need to be upgraded. I’ve bought a few new speakers, but tend to buy used speakers to save $$ I can use on upgrades. Also helps if I decide to move on to something else as I can usually get back what I paid when bought used.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • VR3
    VR3 Posts: 27,970
    If you are open to used, in the price point I would look for older Tyler acoustics linbrook or taylo

    Can find them used 750 to 1500

    Whole other ball game than the rti150
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • K_M
    K_M Posts: 1,627
    edited August 2022
    westly197 wrote: »
    I recently sold my second pair of LSI15’s in favor of keeping these because they sounded better, could have been a mistake… perhaps the LSi’s would have won out with a few dollars in crossover upgrades. I was never crazy about the bass woofer in the LSi, the three woofers in the RTi 150 are fast and tight with good power.

    This may simply come down to personal preference.

    Having owned Lsi15 in the past, and in fact most of the Lsi line, Their bass was their only weak point to me. ( a bit boomy or bloated and not quite deep enough for their size)

    Are you saying you thought the Rti 150 trounced the mids, highs and imaging of the Lsi 15 also?

  • westly197
    westly197 Posts: 13
    edited August 2022
    So I still have a full set of LSI speakers, LSI12’s, LSIC, LSI/FX that I use in my surround setup with a huge SVS tube subwoofer. I’ve always been happy with it, running off an Emotiva RMC-1L and XPA-7 Gen 2. I always felt the highs were better and mids more clear then my older Polk’s. The center has some box sound, I added no-res foam damping material to it and is very much improved - no other modification at this point.

    So when I got a deal on another pair of LSI12’s I picked them up and put them in my 2 channel room. Over the next few years I tried several speakers and upgraded from a vintage Adcom system system to an ATI 4002 Signature Amp, Emotiva differential XSP-1 Gen 2, Marantz HD-DAC-1, Etc. With each configuration changes I listened to both the stock LSI-12 and the partially upgraded RTi-150, and every time I found I enjoyed the RTi-150 more. I asked my wife and a couple neighbors, and they also came to the same conclusion. They don’t seem as crisp, but very natural and believable. I also picked up another RTi-150 pair and was always disappointed with them and quickly went back to the upgraded 150’s as the stock ones just didn’t impress after listening to the upgraded ones.

    So now I bit the bullet and moved the partly upgraded x-over and put it in the second set, used in a loft basic secondary system - wanted to keep them as spares. I added no-rez, built all new x-overs in 3 parts due to the size. I used a Sonicap for the tweeter with a Jantzen Z-Superior capacitor .47mF as well as the optional one on the schematic from Polk, better resistors, and quality air inductors and installed at 90 degree angle to the mid woofer as far away as possible. Used the Solen caps for the mid woofer due to the high values, same for the rest of the components. The 3rd crossover I installed on the original location with all ferris metal removed, Auden 68 uF and Solen 62 uF to hit the 130 uF value, same for the rest of the parts. The sound is improved nicely, and I’d describe it more as making the speakers disappear. It just sounds more natural and doesn’t sound like it’s coming from the speakers at all or from boxes, perhaps not quite the level of open baffle, but much improved. I can listen at decent levels for multiple hours with no fatigue, have great imaging but perhaps less precise then some speakers. I think they sound far better then the $800 I spent on them (great deal when I bought them), and in many ways better then $3800 speakers I tried in the same room. So far quite happy with the upgrade.

    I’m not sure how much the LSI could be improved, they are starting from a better place with better wires and a couple basic poly caps, not super great, but several steps from what came on the RT & RTi lines. I am tempted to upgrade my LSI front 3 speakers and see where that gets me. They have lower value caps so will be less costly, but I paid more for them so I’d have more invested. I also can’t access the center channel schematic and the author is no longer on the forum, I can try to measure the inductors, but it’s not always completely accurate.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • h4vbnjcq2ctr.jpeg
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    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • I spent an hour writing a post that just disappeared?
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • pitdogg2
    pitdogg2 Posts: 24,481
    edited August 2022
    Check your draft's
    Quick links at the bottom on mobile or right side top on pc
  • F1nut
    F1nut Posts: 49,711
    edited August 2022
    Never cover a resistor in hot glue or whatever that goo is. BAD...BAD...BAD!

    And what's up with those twisted leads!?!
    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

  • Clipdat
    Clipdat Posts: 12,560
    Looks like maybe he just twisted and glued vs soldered? Not sure.
  • westly197
    westly197 Posts: 13
    edited August 2022
    Oh no, it’s all soldered very well. Makes sense that the glue could hold in heat, so probably would have been better to keep away from the resistors, but they should be ok as they are double the wattage rating of the originals. Really the glue was to prevent any vibration, the original Polk parts were glued down, but only on the bottom, I might have gotten carried away. The crossover was made point to point, twisted together, then soldered, glued, and zip tied down. Also keep in mind I still had to attach the wires once the crossover were in place, and more solder was added at that point. Twisting together is far superior to just soldering, having the leads directly in contact with each other provides a superior connection with better materials then solder, it is then sealed with solder. If you read around you will find this is common for upgraded crossovers. PS, I was going to correct the name, not LSI12, it’s LSI15 but the post disappeared and didn’t Re-appear until it was too late to edit.
    Post edited by westly197 on
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • F1nut
    F1nut Posts: 49,711
    edited August 2022
    Not sure where you read it is common, I've never seen it before. AK perhaps? Anyway, twisting lead wires is a very bad idea. The proper joint is a soldered hook.
    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: 49,711
    Out of curiosity I spent 10 minutes or so searching for images of point to point speaker crossover solder work. Not a single example of twisted lead wires, not one. Plenty of hook type joints though.
    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

  • westly197
    westly197 Posts: 13
    edited August 2022
    Well I give you it’s not scalable or sustainable for mass production, it has some risk of damage to the parts if done incorrectly, and will offer only a very, very minimal electrical advantage. It is also harder to service if ever necessary, but I and many others won’t agree it is inferior electrically or not a good way to build a custom hobby crossover where you don’t have a circuit board. I’ve seen hundreds done this way and feel it offers no downside for sonics or ease when doing a single one-off project. I do agree it’s not the way to do it for any kind of production run, so your statement is not wrong either. I did not come up with this idea, I actually copied what others had done and the recommendation of the company I purchased the majority parts from. They had better pricing and offered help and advice on the project.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • F1nut
    F1nut Posts: 49,711
    You've seen hundreds!?! Where? Post some photos of them please.

    BTW, I wasn't speaking of mass production.
    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

  • westly197
    westly197 Posts: 13
    edited August 2022
    Just a few from a 30 second search:

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    1czaxhdjjmcf.jpeg
    dl3vlbrttdbf.jpeg
    jautok28xge5.jpeg
    hcfz0v8ow3zz.jpeg
    Post edited by westly197 on
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • pitdogg2
    pitdogg2 Posts: 24,481
    edited August 2022
    I'd never do that. IF I was it would only be the ends while holding one side in pliers so my twisting the ends never progressed back toward the caps, resistor or inductors.
    That just doesn't look like good connections, even after solder.
  • Clipdat
    Clipdat Posts: 12,560
    Visually I do not like how that looks.
  • Looks wise some like, some don’t. This is the first time I did it this way, last time I did it the soldered hook method.

    [l4l7tkhoyupt.jpeg

    A long time ago I also used an etching kit to make a circuit board, too much cost and effort, and for no advantage.

    I think it look fine and I’ll probably never see it again except in a photo, and I think functionally it is superior and took less effort and time for a one off, a win in my book.
    - Wes
    Current: Polk LSi15, LSiC, LSiFX, R900, RTi150, CS400i, PSW650, SVS 2039 PCI, SVS SB1000 Pro, Magnepan LRS, Magnepan 1.6QR, Airmotiv B1+
    Former Polk Speakers: RT3000P, RT1000, RT800, RT55, CS400, CSi3, FXi5, RTi70 PSW10
  • F1nut
    F1nut Posts: 49,711
    westly197 wrote: »
    Just a few from a 30 second search:

    ahaismjq2a6q.jpeg
    nj5ly9oeijl6.jpeg
    zzuwkzauw8zw.jpeg
    1czaxhdjjmcf.jpeg
    dl3vlbrttdbf.jpeg
    jautok28xge5.jpeg

    Horrible, just horrible.
    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: 4,137
    I would say WBT oxygen free copper crimp sleeves would be the way I would go. I really don't like all that twisting. I would want closer to a single point connection that is rock solid. Maybe backfill with a minimal amount of silver solder. I think if you crimp it really well there is no need for the solder and it is almost a pressure weld joint.

    For serviceability in the future you can leave a little slack in the leads.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
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