Hi
I have two-way speakers, which are nearly 25 years old but in excellent condition. However, there are a mix of electrolytic as well as polypropylene capacitors on both the tweeter and bass sections on the cross over which have never been changed.
The question is; do I change just the one electrolytic capacitor for polypropylene in the tweeter section and leave the other polypropylene caps alone? Or, change all the electrolytics out on both tweeter and bass section for polypropylene? Alternatively, change all caps, both electrolytic and polypropylene for new polypropylene so all caps are the same age and quality?
I have two-way speakers, which are nearly 25 years old but in excellent condition. However, there are a mix of electrolytic as well as polypropylene capacitors on both the tweeter and bass sections on the cross over which have never been changed.
The question is; do I change just the one electrolytic capacitor for polypropylene in the tweeter section and leave the other polypropylene caps alone? Or, change all the electrolytics out on both tweeter and bass section for polypropylene? Alternatively, change all caps, both electrolytic and polypropylene for new polypropylene so all caps are the same age and quality?
If you were changing tyres on your car I could see this retaining the original handling characteristics. This is not the same.
Polypropylene caps should not age. I wouldn't waste money replacing them. Electrolytics do age badly (the liquid electrolyte dries out). They also have different electrical characteristics to poly, so expect a different sound even if the electrolytics are new. You may want to check the equivalent series resistance of the electrolytics and add a series resistor to the poly replacements. Series resistance can sometimes be important. Also note that the inductance of the two types may be different, which may be audible.
Mike, in order to to return your speakers as closely as possible to the way they sounded 25 years ago, simply renew the electrolytic capacitors.
The new caps will be good for at least another 25 years!
As the others imply, doing otherwise involves access to the appropriate measurement tools.
The new caps will be good for at least another 25 years!
As the others imply, doing otherwise involves access to the appropriate measurement tools.
The easiest thing would be to measure the electrolytics, it's not certain they are a problem. We could assist with some basic simulating if OP wants a rough idea of what parts will affect what.
These are hardly vintage speakers, so the electrolytics are probably still within tolerance.
Do you have a Capacitance and ESR Meter with which to measure the electrolytics, Mike?
https://cpc.farnell.com/peak/esr70/esrcapacitance-meter/dp/IN06855
Do you have a Capacitance and ESR Meter with which to measure the electrolytics, Mike?
https://cpc.farnell.com/peak/esr70/esrcapacitance-meter/dp/IN06855
@Galu
"These are hardly vintage speakers, so the electrolytics are probably still within tolerance."
Given the fact that any speaker//amp/etc., is vintage, its capacitors installed at the factory are from vendors of various brands when it was manufactured.
Some last ages, others don't.
My 1988 'vintage' Advent Maestro speakers have no audible signs of deteriorated caps in their crossovers.
Last time I checked them, in 1994 when I replaced the rotted woofers with a better driver, those crossover caps were dead-on fine.
So with that said, I'm not going to bother with what so many seem to succumb to.
Which in this case is that annoying and overblown internet-driven paranoia of "recapping".
"These are hardly vintage speakers, so the electrolytics are probably still within tolerance."
Given the fact that any speaker//amp/etc., is vintage, its capacitors installed at the factory are from vendors of various brands when it was manufactured.
Some last ages, others don't.
My 1988 'vintage' Advent Maestro speakers have no audible signs of deteriorated caps in their crossovers.
Last time I checked them, in 1994 when I replaced the rotted woofers with a better driver, those crossover caps were dead-on fine.
So with that said, I'm not going to bother with what so many seem to succumb to.
Which in this case is that annoying and overblown internet-driven paranoia of "recapping".
I agree with the last few posts. Obviously, the easiest thing is to treat the electrolytics as innocent until proven guilty. Beyond that it's a bit of a judgment call. In my judgment, polys are better than electrolytics if only because they are not as microphonic, and the speaker cabinet is a very loud space. I think listening comparisons are the surest way to choose between capacitor options.
@Mikeinstereo Is there any other reason that you feel like changing the caps is necessary other than their age? Has the sound quality changed or diminished in some way or is this one of those "change for the sake of change" kind of deals where you're just looking for something to tinker with?
If Mike is indeed suffering from a case of what is clinically known as crossovus upgraditus, the simple act of renewing the electrolytics may be sufficient to provide a cure. 🙂
And certainly cheaper that first buying a £70 Capacitance and ESR Meter to test the old ones!
Out of interest, I wonder if Mike will tell us which make and model of two-way speakers he has?
What are you looking to achieve? Do you like these speakers? Want them better? More clarity and willing to put some money into them? If all yes, to my mind the objective is to put better parts in all the way around with particular focus on removing any and all electrolytics . From there look at the resistors and inductors, move to wire wound resistors, air core inductors, but then it starts to add to the overall bill, and a determination must be made as to what the limit is. Age alone, probably not a huge factor, quality - yes.
If they are low end speakers, it is quite likely that the cheapest caps were used.
Even then I would not replace them unless damage was apparent.
It will be lipstick...unless you change the drivers as well, not going to achieve much.
Speaker aficionados here will tell you that cone thickness, cone material, voice coil clearance, magnet quality, and so on have a real effect on performance. Even the crossover, cabinet material and stuffing are important.
And we all lose hearing range as we grow older. So it becomes difficult to tell between superlative and regular speakers.
My advice is to get another set of speakers, should be available used at a price which will be less than the repair cost.
And should you decide to change them, use high quality ordinary caps, most of the audiophile capacitor nonsense is just that.
Further, graphic type multi meters are sold here, prices starting about $15, and can measure capacitance...do not trust them more than telling you if they are out of whack.
And sometimes capacitors will reform after some hours of use (after long periods in storage), so measure them after regular use.
Even then I would not replace them unless damage was apparent.
It will be lipstick...unless you change the drivers as well, not going to achieve much.
Speaker aficionados here will tell you that cone thickness, cone material, voice coil clearance, magnet quality, and so on have a real effect on performance. Even the crossover, cabinet material and stuffing are important.
And we all lose hearing range as we grow older. So it becomes difficult to tell between superlative and regular speakers.
My advice is to get another set of speakers, should be available used at a price which will be less than the repair cost.
And should you decide to change them, use high quality ordinary caps, most of the audiophile capacitor nonsense is just that.
Further, graphic type multi meters are sold here, prices starting about $15, and can measure capacitance...do not trust them more than telling you if they are out of whack.
And sometimes capacitors will reform after some hours of use (after long periods in storage), so measure them after regular use.
Thanks for all of the replies. There is certainly plenty to think about. I will put aside some time this summer to experiment!
Get some nicer film caps and put those in, do the resistors while you're at it, they're relatively cheap. Looking for more adventure, replace the wire with something nice and solder it all direct to the endpoints. That will change them to the best they'll probably be. Break them in for a week+, it will be a rewarding experience I'm sure.