[dunan]

Hey,


I was just looking at some different websites and came across this page, a user review for polk monitor 40's. The user changed out a simple capacitor, and claims much better sound all around - bass, mids, treble....is this possible? I mean I'm sure it is, but it can't be that easy, can it?


He used these caps and said this in his review:

http://www.parts-express.com/pe/show...number=027-288

Quote:
Just got them a week ago.They sounded okay but was lacking some bass.Naturally,I opened them up,pulled out the crossover and said "DAMMIT". Again, K-Mart cheap Chinese electrolytic capacitors..no wonder ! Well,out they went and immediately in went Jantzen Z-Standard poly caps. Much better,definitely more bass,solid midrange where vocals excell,and the tweeter is much cleaner sounding.


I'm starting to really like these speakers a lot since I swapped out the capacitors.Thats all i did on this set and it made a good 40% improvement thats not placebo.My 45 year old ears still work. Now I have $900.00 sound for $150.00(speakers) + 35.00(Jantzen Z-Standard caps). for $175.00 investment.

If so, the 35$ he spent on the caps looks like a worthwhile upgrade, but will obviously void a warranty. I'd like to do this to my monitor 70's/center channel if it will work. Changing the caps should be a piece of cake. Seeing as my monitor 70's are from 2006 (i think) i dont believe they'd be under warranty still, but I really doubt I'd need the warranty for them anyway at this point.


Should I try it and see what happens? I'm getting the upgrade 'itch' (looking for a cleaner sound) but have no $$, so if changing a couple caps will give a different sound all together, I'm willing to try it.



Suggestions?

 

[chashint]

Doubtful.

 

[Dennis Murphy]



Quote:
Originally Posted by chashint /forum/post/20859983


Doubtful.

I've participated in a number of blind A-B comparisons with caps, and they always yield the same results--no difference. The only possibly legitimate complaint about using NPE caps in the woofer circuit is that they might leak over time and change value. And I have tested one line of NPE's that had very wide tolerances. The Bennics from Madisound were spot on, however. If you have a little change lying around, and if the series capacitor(s) in the tweeter circuit are NPE's, you might replace it (them) with a decent poly cap like the Jantzens. Typical values for tweeter caps are 4.7 uf to 8.2 uf, and that shouldn't cause you much financial grief. I doubt that you will hear a difference, but you might sleep better. If by chance you do think you hear an improvement, (and it will probably just be your imagination), you might replace the woofer cap. It can't hurt, and it might be more stable over time. However, the bottom line here is that there's no objective evidence that cap upgrades help, and no logical explanation as to why they might help other than the issue of long-term stability and possibly poor quality control for some brands.

 

[tony123]

You can look through my construction thread and find where I documented my experience.


My LaScala were 30 years old and it is recommended by the manufacturer to replace capacitors because they dry out and fall out of spec over that length of time. It did, in fact, have an improvement on sound. I've since also experimented with polycarbonate and metal film bypass caps. I could percieve the polycarbonate, but not the metal film.

 

[Colm]

If there isn't something wrong with the capacitors in the first places, it is not likely replacing them will result in an audible difference. Obvious targets for replacement are electrolytic and paper in oil capacitors which generally do not age gracefully. Film capacitors generally don't need replacing.


Frankly, there is nothing wrong with electrolytics where they are typically used (where large values are needed) as long as they haven't degraded. They do tend to have more hysteresis than other types, but it doesn't seem to hurt the sound significantly.


Changing capacitors is not going to make a $150 speaker sound like a $900 one. At best it will probably return it to something closer to its original performance.

 

[Dave1027]

Is the OP talking about replacing the electrolytic caps with identical value film caps? Or modding by changing the values and yes, the tonal character of a speaker? Either one can yield positive results. The latter much more dramatic of a difference. My BICs are highly modded and they sound like a totally different speaker than stock. You better know what you are doing though. Getting the sound just the way you want it is not as easy as simply throwing in new caps. Getting the values correct with all the different variables is a major process.

 

[Colm]

OP linked to 33uF capacitor, which logically would be part of the woofer filter. Replacing a properly function electrolytic there with a film capacitor won't yield an audible result, let alone what the guy he is reading claimed.


If you start changing values, it might be possible to get a little better performance at the crossover points (measurable if not audible), if you know the actual impedances of the components at the crossover points. Individual components vary, and speaker manufacturers typically use the closest standard value instead of the exact value for crossover components. But that is probably beyond OP at this point.


Now, if you want to completely redesign the crossover, that is another story...

 

[dunan]

I'm sure you guys know your stuff, I was just curious to see if trying it would have yielded some good results.


I won't try it at this point, but if the responses were overly positive, I'd have experimented and seen what would have happened.

 

[truwarrior22]

I've upgraded basically my whole crossover in my BP7000SC, I can't say it made a night and day difference, but it does sound a little better. The time spent on proper speaker placement well out weighs the cost to upgrade the crossovers. If you don't like how your speakers sound now, I don't think you'll really like how they sound after replaceing the crossover parts.

 

[Bud Dickman]

Over the years I've done a number of Xover upgrades for my self and a few customers with results varying from slight improvements, to quite noticeable improvements. However there are a few "rules" to consider.


1. You cant polish a turd. If the speaker was very cheap such as a modern speaker in the $250/pair or less, you are usually dealing with cheap cabinets and internal wiring that will make Xover improvements much less noticeable. Don't spend a lot on trying to upgrade them or leave them alone altogether. Sometimes a cheap poly bypass cap with the stock electrolytic is about all you should try or you will be throwing your money away.


2. I've found the greatest improvements to be had on mid priced speakers, (~$400 - $1200). Some Klipsch classic series speakers come to mind here. I've done things to improve the seal of the cabinets, and upgraded the internal wiring to some basic Audioquest or Kimber, that helped the imaging quite a bit, and left the Xovers alone. Consider the complexity of the Xovers. I once owned a pair of B&W DM7mkII speakers that had a very complex Xover so I would have had to spend hundreds to upgrade them. It wasn't worth it so I left them alone.


3. Electrolytic caps do not make great Xovers, but manufacturers use them because they are cheap. You may wonder why a company didn't spend another $25 to use better grade capacitors and resistors, but that could end up meaning that the retail price would be $100 higher, and people are budget minded.


Bud

 

[Bud Dickman]



Quote:
Originally Posted by tony123 /forum/post/20860230


You can look through my construction thread and find where I documented my experience.


My LaScala were 30 years old and it is recommended by the manufacturer to replace capacitors because they dry out and fall out of spec over that length of time. It did, in fact, have an improvement on sound. I've since also experimented with polycarbonate and metal film bypass caps. I could percieve the polycarbonate, but not the metal film.

LaScalas, as well as Heresys, Forte II, etc. from he 70's and 80's are prime candidates for upgrades to internal wiring and upgrades that seal the cabinets better, dampen horn resonance, etc. I sold Klipsch for years and it was common for me to have pairs cranked up and feel the cabinets "breathe" around the joints. Even on ported speakers.


Bud

 

[tony123]

Bud, can you expand on some of the techniques used in dampening and sealing. I've also got the old nasty wires inside the cabinets. Next time I get back behind the screen I'll replace all that too.

 

[Bud Dickman]

Quote:

Originally Posted by tony123 Bud, can you expand on some of the techniques used in dampening and sealing. I've also got the old nasty wires inside the cabinets. Next time I get back behind the screen I'll replace all that too.

The last pair I did was probably 15+ years ago...you can dampen the horns (the back side) with plumbers putty and then if you don't like it, it can be removed. I generally did this with the older models that used metal horns, the ones from the late 80's and newer used plastic and "ringing" wasn't as much of an issue, so the putty trick may go too far. Generic Dynamat type material can also be used on the back of the woofer baskets. I've also used the plumbers putty (the rope kind) on the inside corner joints of the cabinet. Make sure you get the really sticky type and the surface is clean because you dont want it to come off and drop to the bottom of the cabinet. You can also use silicone caulking applied liberally and then smoothed out with your finger or a plastic putty tool. Whichever you use, make sure to push it in well so you get a good seal.


For replacing the wiring I had really good results with the old Audioquest Type 2 wire, but I'm not sure if they make that anymore. Basically use the round stuff thats less than $2 a foot, you dont need to go real expensive. If you can push it into the corners with the putty it will also help it from vibrating from internal cabinet pressure, which will help slightly to increase fine detail. Most of these tweaks are slight by themselves, but cumulatively can be pretty noticeable. Although one of my guys who owned Quartets only had time to do the wire upgrade on one speaker one night and said it was noticeably louder and clearer than the other until he had time to do the other one.


Oh, and if you can run your Klipsch with a tube amp and preamp, thats the best upgrade of all But that costs a bit more.


Good luck and happy listening!

Bud

 

[tony123]

Thanks Bud. I'll put all that on my list for the next time I have the cabinets pulled out. I'm pretty sure I have the metal horns, but also pretty sure I don't notice ringing. Still, I'll give it a shot.

 

[Bud Dickman]



Quote:
Originally Posted by tony123 /forum/post/20876371


Thanks Bud. I'll put all that on my list for the next time I have the cabinets pulled out. I'm pretty sure I have the metal horns, but also pretty sure I don't notice ringing. Still, I'll give it a shot.

I believe "ringing" is the technical term, but in reality it's usually perceived as a harshness in certain middle and high frequencies. The putty trick usually smooths things out. You CAN go too far with the putty, start off with a few small blobs mashed onto the back of the horn flares and then increase the amounts gradually until you get the desired results. You can remove some of it when you reach the point of going too far.


Bud

 

[twc5964]

I'm the one the op is referring too regarding the review on my capacitor swap out in the monitor 40's. Of course,I'm 1 1/2 years late finding this thread.I can say using the Jantzens made a huge improvement.I have since used the Z-Superior which made them sound even better.Been doing this for many years with all kinds of audio equipment-especially speakers.I also swapped out the caps with Jantzens in my Monitor 30's with dramatic improvement in sound.Considering the speakers are low end this is as far as I wanted to go with these speakers. Some claim it's a waste of time doing this and they are entitled to their opinion..I can say for a fact it has elevated the Polks to another level.Still using them-still loving them.

 

[mhrischuk]

Sorry for butting in. I have a question on this pair of old Infinity SS2003 speakers. I'm in the process of re-foaming them so while I have them apart I saw somewhere where they recommended a poly cap upgrade. Looking at these pics, can you guys recommend if it's worth it and which ones I should replace. Looks like there are two caps in place.


Thanks






Mike

 

[Bill Fitzmaurice]

Both of those caps are NPE. Chances are the smaller is in the high-pass filter, so it might benefit from swapping out for a poly. Then again, it might not. Just as with high priced wire chances are any improvement can be chalked up to placebo effect. If you're spending five bucks for a Dayton then what the heck, but if it's fifty bucks for a Mundorf, save your money.

 

[mhrischuk]

Thanks Bill.

 

[blake18]

I know this is an old thread, but I came across it in my search, and I must say my 2 cents. With respect, changing out Capacitors makes a huge difference if you use higher quality ones than stock. I put better (from PE) caps, resistors, and inductors in my Klipsch RF-3 II speakers and the difference is absolutely NIGHT AND DAY. Without question. Anyone I ask who heard them before the upgrade also confirmed there was a massive difference. Like buying all new higher quality speakers. Don't listen to those saying there isn't a difference, THERE IS.

A lot of speaker manufacturers skimp on their crossover networks, but I assure you, there is a huge difference in sound with better parts. For example, many manufacturers use crappy Electrolytic caps, where-as film and foil or metalized polypropylene caps sound far far better. Same thing with the crappy quality grainy resistors many use, Mills resistors sound far superior. Biggest place they skimp, however, is the inductors. Many speaker companies use horrible sounding constraining tiny gauge air core inductors. Upgrade them to some nice 12-14 gauge inductors, and the difference is astonishing.

I am unsure how anyone could possibly claim the crossover on the top (pictured below) doesn't sound better than the stock crossover on the bottom. It's simply a nonsensical thing to say. It is NOT placebo. Anyone claiming that has simply never heard a properly upgraded crossover network from a small low quality stock crossover. A quality crossover network is every bit as important as your drivers, bracing, and over enclosure design. It is the brains of your speakers, of course it makes a difference!!

Also note, there is not just a difference from swapping out old caps, as the caps on my personal speakers were still in good condition and fully function. Quality difference, like with drivers, makes all the difference.