Tweeters or Capacitors First?

ben62670

Sorry. I meant http://www.soniccraft.com/mills_resistors.htm not Madisound.com

TennMan

That explains why I couldn't find them there.

PolkMaster1

TennMan wrote: »

I'm new to upgrading speakers and didn't realize the binding post would be so expensive. Are they really worth the extra cost?

Yes, they make a difference. I would go with the Vampires. I used the Cardas CCGR for a while but was never pleased with it. Sold it off and went with the Vampires that you see in the hyperlinks. It is FANTASTIC!!! However I used this in other equipment, not on the Polks - the Polk Binding Posts I have are fantastic!!!

PolkMaster1

TennMan wrote: »

While on the subject of improvements... I was thinking I might need to address the seals/gaskets for the drivers while I'm into it. Are gaskets available for the drivers in the 10s? If not what should I do to ensure a good tight seal?

I've read that no air leakage is important for good bass response and I can see why with the design of the cabinet with the passive radiator.

Use Mortite to seal the gaskets. You can get it at Home Depot for a few $$$. It is WELL WORTH IT!!! I do not recommend using any other substitute (such as other weather stripping material) based on what I heard - it does not substitute well as the Mortite does.

MJ

heiney9

Mortite works well, there are some minor precautions you should pay attention to. Those are posted here towards the end of the thread.

The photo's at the end are missing and I can't seem to get them from my Photobucket page currently after I moved them into their own folder. The narrative should suffice.

http://www.polkaudio.com/forums/showthread.php?t=51420&highlight=5b*

H9

TennMan

I'll have to see if the local Home Depot has the mortite.

h9 that is a long thread. You sure did a lot of work on those 5Bs. Sure would be nice to see the photos of the mortite being applied but I appreciate the description as well. It points me in the right direction to get started.

dcoil

When you call Soniccraft, mention that you are a CP member. They are very familiar with helping CP members get caps and resistors for XO'r upgrades. Ask to talk to the tech folks, not just the order people who, from my experience, didn't have near the knowledge as the Tech dept. They also gave me a pretty good discount :cool:

dcoil

Also, I almost didn't upgrade my tweeters on my SRS. I heard about the slight rise with the SL2000, but I also don't spend money on something unless I'm pretty sure (by gathering lots of info and opinions) I will be pleased with it. I had 8 tweeters to replace, and even at the CP discount of $48 each, this is a bit of change. But I kept reading over and over by the more seasoned forum members about how much better the RDO's sounded. So I bit the bullet and did the tweeters. Well, I am not disappointed! There are spots on several of my favorite tracks that I either had to turn down the volume or I would cringe just a bit (mostly sax, and a lone crash cymbal in one track). Now these spots sound great and in comparison much more realistic and accurate. Through this I have also figured out what 'fatiguing' means, as I can now listen for hours, and the end of my session sounds just as good and fresh as the beginning. :biggrin:

PolkMaster1

dcoil wrote: »

Also, I almost didn't upgrade my tweeters on my SRS. I heard about the slight rise with the SL2000, but I also don't spend money on something unless I'm pretty sure (by gathering lots of info and opinions) I will be pleased with it. I had 8 tweeters to replace, and even at the CP discount of $48 each, this is a bit of change. But I kept reading over and over by the more seasoned forum members about how much better the RDO's sounded. So I bit the bullet and did the tweeters. Well, I am not disappointed! There are spots on several of my favorite tracks that I either had to turn down the volume or I would cringe just a bit (mostly sax, and a lone crash cymbal in one track). Now these spots sound great and in comparison much more realistic and accurate. Through this I have also figured out what 'fatiguing' means, as I can now listen for hours, and the end of my session sounds just as good and fresh as the beginning. :biggrin:

I felt the same way and held off on replacing my SL-3000s for the RD0198s until last year. As you discovered - it was money well spent. I was able to sell my SL-3000s here on Polk to help offset the cost of the RD0198s.

PolkClyde

Schurkey wrote: »

"I" would fix what I had before buying more equipment.

Therefore, repair/upgrade the crossovers BEFORE buying new tweeters, buy new tweeters BEFORE buying another amp/receiver.

But, if you don't know how to up-grade the crossovers,then what do you do? it's hard to get someone from the forum to do it,that's understandable.I'll have to figure it out myself.

TennMan

That's some strong testimony to the value of changing to the RDOs. I'm starting to be convinced that they are that much better.

Thank you all for the information!

heiney9

They are very much worth it. I was skeptical for a long time and finally bought them and wished I had done it a lot sooner. These 2 mods (new caps/resistors and RD0 tweets) take the speaker to a whole new level and you'll be set for many years to come.

H9

heiney9

My Home Depot didn't carry the brand Mortite, but the MD brand is the exact same stuff. It has the consistency of putty, it's not foam.

george daniel

TennMan wrote: »

That's some strong testimony to the value of changing to the RDOs. I'm starting to be convinced that they are that much better.

Thank you all for the information!

Trust you ears,,IMHO totally worth it.YMMV.

TennMan

Thanks h9. A picture is worth a thousand words!

Schurkey

PolkClyde wrote: »

But, if you don't know how to up-grade the crossovers,then what do you do? it's hard to get someone from the forum to do it,that's understandable.

If you don't know how to fix your car...what do you do?

If you don't know how to install a water heater...what do you do?

If you can't shingle a roof...what do you do?

As The Wise Man once said: "Never underestimate the power of the greenie (dollars) to solve problems."

Having said that, there's really not much to it provided you have a soldering iron, appropriate solder and flux, and the skillset to use 'em and to recognize a capacitor from a resistor from an inductor. True enough, not everyone has that skillset--but there's no "engineering" involved, it's just a parts swap. Remove the old component, install an equivalent-or-better new component in its place. The most difficult thing aside from paying for the parts is that the new component may have a physically larger size than the original; and you might have to get creative in how the new piece is mounted to the board.

It helps to do one crossover at a time, and to take photos as you dis-assemble so you remember which capacitor lead went into which hole.

The original parts were slathered in hot-melt glue to provide stability to the individual components; do the same thing to the new stuff.

EXAMPLE: My SDA 1B crossovers had much larger (physical size) capacitors installed, I had to lift the one set on top of the other set, and then extend the leads to reach the circuit board with short jumper wires.



The new parts were MUCH larger than the originals:
Original parts were 1 130uf + 1 55uf (?) capacitor, total 185uf at + or - 10% (I think) tolerance.
New parts are two 91uf capacitors; total 182uf at + or - 3% tolerance.

Original parts were 2 34uf capacitors + or - 10% (I think) tolerance.
New parts are two 33uf capacitors + or - 5% tolerance.

PolkClyde wrote: »

I'll have to figure it out myself.

I tried for awhile to get a forum member to fix my crossovers; but it seemed like we couldn't ever connect to discuss the work. I heard later that he had some health issues and wasn't feeling well.

About a year later, I quit procrastinating and just dove in. I've done very little electronics work, although I can solder copper water pipes and vehicle wiring. My electronics background is limited to examination of circuit boards looking for crappy or broken solder joints. If I can do it...you can, too.

george daniel

wow,, you sure got em' packed in there--nice

TennMan

Schurkey,
Thanks for the encouragement. The photos helped me understand a little more about what is involved in replacing the caps. I have very limited experience soldering but I have lots of time on my hands to do some practicing before actually taking on the job of updating the crossovers. Everyone here has been very helpful and I appreciate it.

Schurkey

TennMan wrote: »

Schurkey,
Thanks for the encouragement. The photos helped me understand a little more about what is involved in replacing the caps. I have very limited experience soldering but I have lots of time on my hands to do some practicing before actually taking on the job of updating the crossovers. Everyone here has been very helpful and I appreciate it.

It's exactly the same for the resistors. Mills (brand name) resistors have been repeatedly suggested on this forum; and after using both Mills and Dayton resistors...the Mills will be all I use if I do this again. The reason is the physical size--Mills are smaller. Therefore they fit the circuit board better. Problem is, my supplier didn't have all the various resistors I needed in the Mills brand. I'd be mighty tempted to use the 5-watt resistors instead of 12-watt, too, again they'd be smaller and therefore easier to load onto the circuit board.

Finding space for the resistors was harder than loading those bigass capacitors.

As for the Mortite and Heiney9 saying the BD brand is the same...I bought the W. J. Dennis brand from my local Menards, and it's also sold by Ace Hardware in an Ace-labeled box. Again, same stuff. His photos of the product could be my photos of the product, but the box is different. If I had it to do over, I wouldn't buy white or grey, I'd buy brown--but it's not that important and if some squishes out and is visible...just scrape it off.

The latest upgrade seems to be replacing the inductors. That's way beyond my experience; I didn't bother. I don't think it's difficult; but inductors seem to be more complicated in terms of finding a suitable replacement--the electrical parameters seem more complex. I don't trust myself to find a replacement that meets all the various specs.

TennMan

The size is a good reason to go with the Mills resistors. They are highly recommended by most everyone here. I noticed that you used Dayton caps. They are more in my price range than the SoniCaps that seem to be so popular. Are you satisfied with them?

Schurkey

TennMan wrote: »

I noticed that you used Dayton caps. They are more in my price range than the SoniCaps that seem to be so popular. Are you satisfied with them?

Absolutely. They beat the hell out of the original equipment caps as supplied by Polk, and they aren't worn-out from 20+ years of use. They're a terrific upgrade. This does not mean they're the ABSOLUTE OPTIMUM; but I'm a firm believer in the 80/20 rule: 80% of the performance for 20% of the price (and price is a concern for me.)

The SDA 1B uses a pair of circular crossover boards, tied together with a tangle of wires. One board covers the high frequencies, one board covers the mid/bass and the SDA drivers.

This is the "before" photo of the two boards. It looks worse than it is.



I used Dayton 1% tolerance caps for the high-frequency crossover board, the caps are smaller-value and the price wasn't bad at all.

The low-frequency crossover board (pictured in my previous post, and the upper one in this photo) uses larger-value caps that aren't available as 1% tolerance through Dayton; the 5% tolerance Daytons are entirely satisfactory as far as I'm concerned. I would consider using just the 3% Erse caps in the low-frequency board instead of Daytons; nobody on this forum had mentioned the Erse brand, but the price was in line with Dayton; and they happened to have those 91uf units that added together were close enough to the 185uf spec for me. I think Dayton offered 90 uf, so the Erse were just a bit closer to Polk's spec, and the tolerance on the Erse is just a bit tighter as well--3% vs. 5% for Dayton.

http://www.erseaudio.com/Products/PulseX250v

The shortest possible story here is: Any of the aftermarket film caps are going to be WAY, WAY better than what Polk installed. Even FRESH cheap 'n' crappy electrolytic caps of the same style Polk installed will be better than the aged and degraded caps you have now. Don't obsess; or perhaps I should say "Don't obsess beyond your financial means."

TennMan

The Erse caps have a closer tolerance and are slightly cheaper. I'm not knowledgeable enough in electronics to know if tolerance tells the whole story when it comes to the best sound. There are a lot of other specs for caps that I don't know how to interpret. Do you feel the Erse caps are superior to Dayton for the crossovers?

Schurkey

TennMan wrote: »

The Erse caps have a closer tolerance and are slightly cheaper.

Yup. Well, closer tolerance than the 5% Daytons, but not closer than the more-expensive 1% Daytons.

TennMan wrote: »

I'm not knowledgeable enough in electronics to know if tolerance tells the whole story when it comes to the best sound.

Tolerance is CERTAINLY not the whole story.

TennMan wrote: »

There are a lot of other specs for caps that I don't know how to interpret. Do you feel the Erse caps are superior to Dayton for the crossovers?

I can't tell you if they're superior to other film caps. I suppose not, given the relatively low price. I'm confident that they're MUCH superior to what Polk installed to begin with; and film caps don't tend to degrade the way electrolytics do, so they'll likely be more stable than the Polk-supplied stuff, too.

I don't doubt that some folks are going to feel the more-expensive caps and resistors and inductors and circuit boards and internal wiring improve the sound. Somewhere out there is someone who fills the cabinet with pure nitrogen instead of ordinary air, like NASCAR does with tires. For me, it's price-to-performance that matters; and losing old electrolytics in favor of ANY brand of film cap has got to be a considerable improvement. That's all I was after.

TennMan

For me, it's price-to-performance that matters; and losing old electrolytics in favor of ANY brand of film cap has got to be a considerable improvement. That's all I was after.

I believe you and I are on the same wavelength when it comes to upgrading the crossovers. I would love to have the top of the line parts but I just can't justify buying the top of the line parts for the 10Bs. They are good speakers and I want to bring them up to factory specs or better but absolute perfection is not my goal. Like you, good sound at a reasonable cost is what I'm after.

I envy you having a pair of SDAs. I have never heard a pair of SDAs but I have read so much about them that I feel like I have. From what I have read they would be my next step up from the 10Bs. If I ever see a pair come up for sale within a reasonable driving distance from me I intend to take a look at them.

Schurkey

TennMan wrote: »

I believe you and I are on the same wavelength when it comes to upgrading the crossovers. I would love to have the top of the line parts but I just can't justify buying the top of the line parts for the 10Bs. They are good speakers and I want to bring them up to factory specs or better but absolute perfection is not my goal. Like you, good sound at a reasonable cost is what I'm after.

Agreed.

What folks lose sight of is that the first part of "upgrading" is to simply FIX defects that have cropped up over time. People buy a used "whatever", and then make some expert-approved modification...and "WALLA!" the product is much better, or faster, or more powerful, or whatever. But is it the magic modification that made the difference, or is is that an actual DEFECTIVE part was replaced? It's SO EASY to kid one's self into thinking that the magic modification is responsible for the big improvement, when merely installing a non-defective replacement part would have made nearly as much difference.

I gotta say, it's nice to "leapfrog"; where the original part(s) have become defective, and rather than replacing with OEM-quality, you go right to the improved parts. It can happen in audio, it can happen with motor vehicles; I suppose that sort of thing can happen in all sorts of human endeavors.

TennMan wrote: »

I envy you having a pair of SDAs. I have never heard a pair of SDAs but I have read so much about them that I feel like I have. From what I have read they would be my next step up from the 10Bs. If I ever see a pair come up for sale within a reasonable driving distance from me I intend to take a look at them.

Bought the 1Bs new, back in '86 or '87. Still have the receipt, somewhere. Store demos, getting blown out in favor of the new model--1C. (Too cheap to wait for the new model; I like discounts!)

Actually went through a love/hate/acceptance/love relationship with them.

Loved 'em when I bought 'em; they were new, shiny toys that replaced a chipboard home-built corner-horn system.

After awhile, and having gotten a subscription to Stereophile; I learned that Polk speakers were gimmicky and barely mid-fi. I had to admit that there was "something" in the sound that bothered me. A mid-range "phaseyness" that I can't describe adequately...but it's hateful. In addition, I never had enough treble to suit me.

Having no money to replace them, I just lived with 'em and their "weirdness" Got so used to 'em that I quit thinking about it. Actually, I neglected them.

Years ago, I figured out the "something" I hated had to do with the SDA circuitry, because it was G-O-N-E when I pulled the SDA interconnect cable. Listened without the cable for a couple years. Missed the imaging; but the tonal response was MUCH improved.

Eventually, I figured out the obvious: The 1B must have a common-ground amp, and my amp that I thought was common-ground actually had 20 ohms of resistance between the channels. A five-dollar home-made jumper cable strapping the grounds together allowed me to put the SDA-cable back in place. That was the single-largest "improvement" I ever made to the "speakers". (Note: All I did was provide what the speaker wanted, and the literature warned about. I shouldn't call it an upgrade or an improvement since it's nothing more than a "repair".) But HOLY CRAP! What a repair!

But that just got me started. From there, I wanted the crossover upgrades; I installed a pair (ONE pair, not both pairs--I'm too cheap!) of RDO 198 tweeters using a crossover modification pioneered by forum member insiredsports on his similar SDA SRS 2s. Which, by the way, was partly done in order to REPLACE one of the existing tweeters which had died somewhere along the line. I also bypassed the tweeter-protection polyswitches. At this point, I've got a pair of small aftermarket ribbon tweeters kludged on to the top of the cabinet, in parallel with the existing tweeters and crossed over at 10K or 11K, I kinda forget.

And I'm back to loving them. For awhile, I coveted the 1Cs...but not any more. My good ol' 1Bs are plenty good enough now.

(Which doesn't mean I'd walk away from some SRSs, if I found 'em at a really advantageous price.) ;>)

TennMan

Reading about your love/hate relationship with the SDAs jolts me back into reality. I had put the SDAs on such a high pedestal that I had never considered that they had problems just like anything else man made. Just goes to prove that the grass is not always greener on the other side. I'm glad that you finally got the bugs worked out and now like the SDAs. I hope that some day I have the opportunity to own a pair of them but until then I'm happy with what I'm hearing from my 10Bs and I'm looking forward to tweaking them to make them even better.

Thanks for all the information you have provided. I appreciate it.

ben62670

I have done about 100 crossovers and other projects for Polkies at a reasonable rates. If you try and contact me and loose touch please don't be offended or think it is intentional. Just remind me again and we'll git-R-done. I still try to help those that want to do it themselves no charge of coarse. As far as tolerence is concerned 5% is fine. When I have tested the Dayton's the 5% caps are usually much closer than that.
Have fun.
Ben

TennMan

Ben, I sent a PM but you were busy at the time. I'll try again later.
Thanks.

gp4jesus

PolkMaster1 wrote: »

...the Polk Binding Posts I have are fantastic!!!

I assume those (BP) that came w/your Polks. BTW: model? I'm a RTi A series fan.

Thnx tony

jcandy

TennMan wrote: »

I've not had my 10Bs long. I've been reading a lot about upgrading from the sl2000 tweeter to the RDO-194 and upgrading the crossovers with new capacitors and resistors.

I'm not quite ready to do either one right now. I want to get fully acquainted with the 10Bs current sound before I start changing anything but I do intend to do upgrades in the future. When I upgrade the 10s I want to do it in a logical step by step manner so I can evaluate each change before proceeding to the next step. What should be my first step? The tweeters or the xo upgrade? Or maybe a new receiver/amp?

Your comments are appreciated.

First, about the RDO, my own measurements, and subjective impressions, indicate that there is very little difference between RDO-194 and "good" SL2000s:

http://www.polkaudio.com/forums/showthread.php?t=106512

Pay attention in particular to post 5. These results generated a great deal of controversy and hostility on this forum, although I received supportive and thankful PMs -- it was almost as if people were afraid to speak their mind in public . Because I have not done a THD comparison between drivers, its possible that the RDO is a lower-distortion unit. On the other hand, people often do not find HF distortion objectionable, so my guess is that THD cannot explain why the RDO is believed to be better. You will note that removing the grill has about as much effect (via diffraction) as switching tweeters. A final possibility is that early batches of the SL2000 had problems that were fixed in later versions. But I have not heard any evidence for this. Maybe someday a Polk engineer will chime in and give us the real story.

Second, regarding other modifications, some posters have (rightly) pointed out that too often modifications are pointless (and can even cause a degradation of performance) unless they address component or enclosure defects. That said, it is known that capacitors can suffer degradation over time, so you may find that a capacitor upgrade is worthwhile (its also easy). Inductor upgrades are more problematic because (1) inductors do not change value over time, (2) inductors also have a DC resistance that should not be changed unless you are prepared to re-engineer the entire crossover. If I were to attempt to "refresh" the crossover, I would build entirely new ones from scratch (matching component values from the original spec), and then swap the new and old and see if there really was an improvement. Finally, doing all of this will be something like voodoo unless you have measurement capability (SPL and impedance). I am working on active 3-way project with a friend using drivers he had lying around. A few measurements showed that his midrange drivers (bought on sale from MCM) were defective. You don't want to be messing around too much with speaker mods without measurement apparatus.

Honestly, the original crossover for the monitor 10 is a rudimentary (that doesn't mean bad) 2nd-order HP, 2nd-order LP combination with a basic RC contour element on the tweeter. It on my (impossibly long) to-do list to completely redesign the crossovers for the monitor 5/7/10 series in order to improve the SPL and power response. As soon as someone volunteers their speakers I'll get started