Audiophile Re-cap active speakers...Which products?

Despite my total ignorance, I plan to refurbish the electronics in my old Meridian DSP5000.2 active speakers. I have a list of recommended parts to solder in place, but can't find two items:


Ansar "Supersound" caps, 3.3uF and 2.2uF 400V
UK distributors are instead selling a brand called Monacor?


Nichicon 100uF 63V caps #UFG1J101MPM which are out-of-stock


I visited Humble Homemade Hifi to learn which 400V "audiophile" caps are out there today, and now wonder if I should simply replace the Ansar with Audience Auricap XO but don't understand anything about component electronics parts compatibility for Meridian amplifier boards.


Please help a confused Newbie.
 
Buy any good brand, those are tiny local probably out of production.
Standard trustworthy are: any Japanese, German, US or Taiwan brand, and Keltron in India.
2.2 and 3.3 /400 V are used in a tube amp?
And too many fakes, buy from reputed sources with a proper warranty and returns policy.
 
If your ansar supersound caps don't have "NP" after the voltage rating, they are plastic film caps. Plastic film caps do not age like electrolytic caps, which evaporate the water out through the seal. Caps marked "NP" after the voltage are electrolytic non-polar caps.
US speaker parts distributor parts-express is selling 2.2 & 3.3 uf 400 v polyprophylene dielectric caps from a house brand, also Audyn, also Jantzen. These are metalized film. Film & foil caps are available, and more expensive.
400 vac speaker caps are used in PA service where voltage can go to 185 peak to peak. If a speaker is unplugged at full volume, the inductive spike can force voltage to 400 or above.
 
No reason to spend crazy money for "audiophile" caps - Meridian makes a great product already and if the caps you are planning on replacing are NOT electrolytic, you don't need to replace them. But go ahead and replace them if you must on only one speaker, then, have an assistant connect one of the speakers in mono and listen to it, then the other without knowing which has the new caps. You won't hear a difference.

Additionally, there is absolutely no need to install 400v caps unless you're dealing with a tube amplifier. Capacitors are more expensive the higher the voltage rating. No reason for it, if the circuit voltage is only 65vdc you will be absolutely fine with even crazy as 100v caps but no need to go 400v. That's rediculous.

Finally, the electrolytics you're planning on changing - are they bulging at the tops? Is there a performance defect you notice audibly? If so, you can find the caps you want at Digikey, Mouser, as well as several other distributors. The main thing you want to ensure is that the caps you're replacing are low ESR and it should say on the cut sheet posted on the distributors website.

Don't buy caps on Ebay - trust me - if they're from a reputable manufacturer most likely a guy found a bunch in the garbage that didn't make the cut when tested, or they're just counterfeit. Stay with a reputable electronics distributor, and don't go nuts for some 'audiophile' 400v extra special blah blah. I guarantee you it's a waste of money.
 
Additionally, there is absolutely no need to install 400v caps unless you're dealing with a tube amplifier. Capacitors are more expensive the higher the voltage rating. No reason for it, if the circuit voltage is only 65vdc you will be absolutely fine with even crazy as 100v caps but no need to go 400v. That's rediculous.
So you never tripped over a wire & disconnected a speaker during a loud stage show? Speakers are INDUCTIVE, and inductors produce high voltage when the current is shut off suddenly. Automobile manufacturers used this effect to fire spark plugs back in the early days.
Tube amp has nothing to do with it, tube amps have a transformer to get voltages on speaker down to the 25 to 50 vac used in 8 ohm speakers.
If the OP is using a 10 vac (12 W) out amp, he could be fine with 100 vac rated speaker caps. If he has a 600 w/ch PA amp that can routinely put out 53 vac, he should use 400 v rated caps. Or expect wonky sounding speakers after the MC, roady, or a groupy trips over the speaker wire in mid-song.
A heavy fall can pull the wire out of a speakon. At least those won't short the amp the way a 1/4 phone plug pulled out 1/4" will. Never heard of this, ask a music shop repairman about shorted output transistors in bar band amps.
You can even estimate the voltage peak. A kappa-pro 15a driver has 1 mH of inductance. Say it is playing at 22 amps, which my PV-1.3k will put out. Say the current shutoff happens in a microsecond. DI/DT is 22 million amps/sec. * 1 mh get 22000 volts. You can't get that fast a shutoff with a switch, the points will arc. But a yanked wire achieves a great air gap in microseconds.
 
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Additionally, there is absolutely no need to install 400v caps unless you're dealing with a tube amplifier. Capacitors are more expensive the higher the voltage rating. No reason for it, if the circuit voltage is only 65vdc you will be absolutely fine with even crazy as 100v caps but no need to go 400v. That's rediculous.

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You're right.

Electrolytic capacitors should ALWAYS be replaced with the indicated working voltage.
They can be replaced - in case of not getting the correct value - by a SLIGHTLY higher value, but going from 65 Vdc to 400 Vdc, significantly alters the capacity of the original, which is very bad for the correct performance of the circuit.


*Duda al sustituir electroliticos de mayor voltaje

" We all know what a capacitor is, they are two plates separated by an insulator called a dielectric.
In the particular case of electrolytics, there is no insulator between the two aluminum plates, but they are submerged in a liquid that when applying voltage forms a thin oxide film on the plates that is insulating and that is what the dielectric forms.
An electrolytic fresh off the production line is not such until voltage is applied that forms the dielectric.
For this reason a capacitor needs a certain voltage for this oxide to occur. The difference between two capacitors of different insulation is the separation between plates, in the high voltage ones it is more, and if the voltage is not enough, the oxide does not form, or not to the necessary extent and therefore the capacitor loses its characteristics.
In practice, a capacitor of this type should not be placed with more than twice the maximum voltage."
 
They can be replaced - in case of not getting the correct value - by a SLIGHTLY higher value, but going from 65 Vdc to 400 Vdc, significantly alters the capacity of the original
If the capacitance is the same, its the same. A higher voltage rating than needed won't change the capacitance or the circuit behaviour (except possibly being somewhat more linear, and slight difference in leakage current).

But higher voltage rating means a much larger capacitor, this is why you don't use unnecessarily high voltage rating - double the rating, 4 times larger volume of cap, all else being equal. (This is because energy content of a capacitor is 0.5 C V^2)

So changing 63V to 400V is replacing with a device about 40 times larger, heavier and more expensive - not a rational act, so unlikely to happen!

Over time aluminium electrolytic capacitors degrade, whether charged or discharged, bipolar or unipolar, and this degradation is mainly a function of temperature, meaning that usually it happens mainly during operation when the equipment internal temperature rises. The best defence is choosing quality brand and a range rated for 105C or higher.


One way to assess capacitors for deterioration is measure the ESR - this rises steeply once the device has reached end of its useful life.