crosover components

[desnoumondo]

hello guys,

i am bussy with making my own speakers and with that my own crossovers. but how do i know i got the right capacitors?? and by that i mean the voltage that de cap can handle.

if someone can have a formula for that it would be great. or are there fixed values fore that??

thanks,

Desnoumondo

[johnnyrichards]

Re: crosover components

For the vast majority of applications, even 100V caps will suffice. 250V is about the standard, but there are caps up to 1000V and depending on who you believe - the higher the voltage, the better the sound.

[desnoumondo]

Re: crosover components

and how is it with power (Watt) handeling??

[Chris Roemer]

Re: crosover components

You can use electrolytic caps (the CHEAP ones, under $1 each) but you can NOT use the MOST COMMON (Polarized) Electrolytic cap, which can have VERY low voltage ratings, like 10v, 25v, and such. You MUST use NON-polarized electrolytics ("npe") caps, OR the next step up (price-wise) are (metallized) polypropylene ("pp"), which are probably used most often.

Unless you're using "Pro Sound" gear (high power / high SPL), 100v (or more) will be fine for your apps. Just the fact that you're asking this question, means that I hope you're not jumping into some high-power system for your first foray into design. There's a lot to learn here.

[desnoumondo]

Re: crosover components

Just the fact that you're asking this question, means that I hope you're not jumping into some high-power system for your first foray into design. There's a lot to learn here.

it is my first speaker building project

[1100xxben]

Re: crosover components

and how is it with power (Watt) handeling??

Caps do not (or at least SHOULD NOT) consume power. They are limited by voltage capacity. The power and impedance of your speaker should give you a rough idea of what voltages your speaker cabinet will see, but depending on where the cap is in your crossover circuit, the voltage will be lower than what the overall cabinet sees.

[desnoumondo]

Re: crosover components

okay i think i said it wrong. i meant how do i be sure my crossover can handle every Watt i be sending my speakers

[Chris Roemer]

Re: crosover components

All you need to know is how many volts your amp can push.
40v into an 8Ω load is 5a. 5a at 40v is 200w. (This is greatly simplified by using DC equivalent, and sound is AC, but it'll still be in the ballpark.)

If your amp is low power (< 50w?), 1st major problem is amp clipping, sending distortion to your tweeter, and possibly ruining it (which turns to most likely ruining it IF you thought you could cross it 1st order).
2nd major problem most likely would be amp clipping (if woofers are small, and have limited Xmax, THEY could go 1st).

If your amp is high power (> 50-100w?), 1st major problem is driving a smaller (lower Xmax) woofer into distortion, or possibly exceeding Xmax and actually physically ruining the woofer. 2nd problem is ruining a tweeter crossed 1st order, then amp clipping, which can also ruin the tweeter.

Your XO not being able to stand the power is definately 3rd, 4th, or 5th down the line after passing these other problems.

Go, you've got more important things to worry about now.

[desnoumondo]

Re: crosover components

Go, you've got more important things to worry about now.

actually this was my only worry about the XO