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rhomanski
07-01-2009, 03:20 AM
hi.just signed up and i have a question.i want to recap some speakers that are old.i am having trouble finding the exact capacitance i need.should i go slightly higher 2.2 instead of 2 or lower 1.8 instead of 2.or does it matter either way.awaiting your replys.regards.ron.

mlsstl
07-01-2009, 04:14 AM
hi.just signed up and i have a question.i want to recap some speakers that are old.i am having trouble finding the exact capacitance i need.should i go slightly higher 2.2 instead of 2 or lower 1.8 instead of 2.or does it matter either way.awaiting your replys.regards.ron.

The answer is in the "it depends" category.

Older mass market speakers often used capacitors with as much as a 20% variance in tolerance to spec. For these type of products it probably isn't worth too much effort to be too precise.

In many modern, high performance speakers the parts tolerance is much tighter.

However, changing the capacitance will affect the frequency response of the crossover. The exact change will vary with where your 2 uF is in the circuit (for tweeter, mid or woofer), the order of the crossover (1st, 2nd, 3rd, etc.). You'd have to do the math to get a better idea of the impact.

You can also use two caps in parallel. Use a 1.8 uF with a 0.2 uF and you'll end up with 2 uF total capacitance. However, this may complicate the physical layout if there isn't adequate room for 2 caps on the crossover board.

rhomanski
07-01-2009, 04:26 AM
it's for a pair of pioneer cs 99a's.not the best speakers but trying to make them a little better for my brother.

JoeE SP9
07-01-2009, 06:00 AM
The values on the caps are the ideal for a given speaker. As mlsstl said, the actual values on inexpensive parts have a wide tolerance. Try to get as close to the ideal values as you can. If you need to place some caps in parallel to achieve this, so be it. This may mean you have to piggyback some of the parts in order to get them connected..Use plastic tie wraps or hot melt glue to securely anchor the parts to the PCB and each other.

Feanor
07-01-2009, 08:58 AM
hi.just signed up and i have a question.i want to recap some speakers that are old.i am having trouble finding the exact capacitance i need.should i go slightly higher 2.2 instead of 2 or lower 1.8 instead of 2.or does it matter either way.awaiting your replys.regards.ron.

In general 2.2 vs. 2 v.s 1.8 won't make a noticable difference, however there is another option.

Capacitors hooked in parallel to each other are additive, that is, two 1 uF caps in parallel are equivalent to a single 2 uF cap. In fact a 1.8 uF cap in parallel with a 0.2 uF will also work.

rhomanski
07-01-2009, 01:22 PM
thanks guys.i ordered the parts to get as close as possible.i just didn't know how the math would work out for that variance in capacitance.whether it would be audible or not.now i just have to wait for my parts.i'll update and let you know in a week or two.regards.ron.

Kevio
07-02-2009, 07:13 AM
Make sure you buy unpolarized capacitors.

JoeE SP9
07-02-2009, 11:27 AM
hi.just signed up and i have a question.i want to recap some speakers that are old.i am having trouble finding the exact capacitance i need.should i go slightly higher 2.2 instead of 2 or lower 1.8 instead of 2.or does it matter either way.awaiting your replys.regards.ron.


Michael Percy Audio has caps including 2uF from several different manufacturers in several price ranges.

http://www.percyaudio.com/Catalog.pdf