sloper Posted June 16, 2017 Posted June 16, 2017 Goodaye all When do people recap the electrolytic caps in a crossover? When there's a problem, after 20years or ???? regards Bruce
Full Range Posted June 16, 2017 Posted June 16, 2017 Answer When they fail When you want to upgrade When the sound is flat or has changed from normal Some electrolytic caps develop what's known as the plague and must be changed
Zaphod Beeblebrox Posted June 16, 2017 Posted June 16, 2017 2 hours ago, sloper said: Goodaye all When do people recap the electrolytic caps in a crossover? When there's a problem, after 20years or ???? regards Bruce Typical bi-polar electrolytic caps used in crossovers have a lifespan of around 2,000 hours @ 85 degrees C. Some may possess a longer operational life, but 2,000 hours is the norm. That said, the 2,000 hour figure is at the rated temperature. Given the fact that most crossover caps operate at temps well below 40 degrees C, then the 2,000 hour figure would typically be something like 10,000 hours or more.
sloper Posted June 16, 2017 Author Posted June 16, 2017 Thankyou. Time to change some 20 yearold caps. Say 3hrs a day, 20k hours, time for a change. regards Bruce 1
Zaphod Beeblebrox Posted June 16, 2017 Posted June 16, 2017 14 minutes ago, sloper said: Thankyou. Time to change some 20 yearold caps. Say 3hrs a day, 20k hours, time for a change. regards Bruce When you do, consider the following: * Where possible, use 100 Volt (or more) rated caps. * Use quality products, since they don't cost much more. * For mids and HF drivers, consider using a good quality plastic film cap. Be aware, however, that some manufacturers tailor their speakers for electros and the result may be a little 'hotter' at the HF end.
mwhouston Posted June 17, 2017 Posted June 17, 2017 I'd say if the caps are 20years sold I'd change them. If you can replace with polies that would be best, poly metal film next. Then NP electros then normal electros last would be the order of high grade to low grade caps. Jaycar yellow Xover caps are 100V rated and Metalised polies. Not up there with Solen polies but a close second.
sloper Posted June 17, 2017 Author Posted June 17, 2017 Only use quality caps. Prefer always to swap type for type, bigger voltage is a good idea. Its for the heathens surround sound mains, sounds a little flat compared to the same on the restored Marantz. And theres no way in hell here getting the Marantz. Bad enough the little Sansui is out there. regards Bruce
Addicted to music Posted June 17, 2017 Posted June 17, 2017 1 hour ago, Zaphod Beeblebrox said: When you do, consider the following: * Where possible, use 100 Volt (or more) rated caps. * Use quality products, since they don't cost much more. * For mids and HF drivers, consider using a good quality plastic film cap. Be aware, however, that some manufacturers tailor their speakers for electros and the result may be a little 'hotter' at the HF end. What at do you mean by "hotter" at the HF?
Full Range Posted June 17, 2017 Posted June 17, 2017 1 minute ago, Addicted to music said: What at do you mean by "hotter" at the HF? At a guess More dominant in the High Frequencies
Zaphod Beeblebrox Posted June 17, 2017 Posted June 17, 2017 1 hour ago, Full Range said: At a guess More dominant in the High Frequencies Correct 1
BLAH BLAH Posted June 17, 2017 Posted June 17, 2017 Certainly a noticeable difference after a re-cap...music is a tad faster and clearer... 1
GhostCoast Posted June 17, 2017 Posted June 17, 2017 there is no definite rule or measure to determine when they'd fail.. too many possibilities involved. some caps might perform fine after 30 years, some fail at 10.. but generally speaking 15-20 year old ordinary caps would be better replaced, and replaced with appropriate types evaluating the value of what you have, or what you want to achieve.. there is no point in spending 200 bucks on expensive caps restoring an ordinary speaker for instance.. unless you have own reasons to love it..
JPete9 Posted June 20, 2017 Posted June 20, 2017 There is definitive rules and measures. ESR, resistance and capacitance. Buy a cheaper esr metre from ebay and test them. If they are within spec, leave them.
GhostCoast Posted June 20, 2017 Posted June 20, 2017 46 minutes ago, JPete9 said: There is definitive rules and measures. ESR, resistance and capacitance. Buy a cheaper esr metre from ebay and test them. If they are within spec, leave them. you need lab grade equipment and knowledge to measure "on load" capacitance of a capacitor... and off load capacitance doesn't tell you much... especially the common cheap ones off ebay...
Sub Sonic Posted June 21, 2017 Posted June 21, 2017 (edited) Get this: http://www.daytonaudio.com/index.php/dats-dayton-audio-test-system.html A very useful and reasonably priced test system for all things speaker related, including capacitors, inductors and speaker impedance curves. Regards, SS Edited June 21, 2017 by Sub Sonic
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