Designing and Building a simple HP crossover

[jaygeorge1979 10+ year member]

oh i know, i love mouser....but i am not entirely sure which parts can be used for crossovers and which cant...when i built my passive in line level crossover, i used a buncha really small really cheap components from them...but when i built the filter used w/ my zaphaudio.com hivi b3s project, the components were bought from madisound and were more expensive...which 220 uF caps are acceptable? i have heard something about using either inductive or noninductive caps...i just dont know which...

thanks

 

[thch 10+ year member]

thanks for your post...you seem very knowledgable...for the record, i am going to school for electrical engineering right now...what do you do?
as for the filter, i may just end up using first order, cuz that inductor is gonna be too expensive...the guy i am building it for said he tried bass blockers, but they dont work??? im gonna suggest crutchfields bass blockers before building em

i'm an EE grad student.

all components have an associtated "quality" due to the capacitace across them and the lead's inductance.* for wirewound power resistors, the inductance can be signifigant. non-inductive resistors are prefered for crossovers.

*most small comonents will have the peak/minimum impedance above 1Ghz, making this a non-issue for most apps. this is why you often see small value ceramic capacitors in parallel with big electrolytics. the ceramic acts as a capacitor at higher frequencies.

 

[SlammeD_SiR 10+ year member]

if i buy compenents that come wit a crossover do i have to worry about all this?? or do i just neeed to wire it right n go pound away ?

i dun wanna do no calualtions n all

 

[thch 10+ year member]

SlammeD SiR:

the orignal poster's question was in regards to a passive highpass filter for the purpose of limiting the bass played by the speaker. This is useful to prevent the smaller speakers from overexurting. It also is useful in blending the sounds from the midrange with the sounds of the subwoofers, but only if maximized bass is not your goal.

The crossovers on component sets do not do this. The component set crossovers are only to blend the sounds from the tweeter with the sounds from the midrange. Many users will use an external amplifier for component speakers and this amplifier will have a highpass option. Some source units will also have a highpass option. Using a pre-amplifier high pass filter, the bass can be removed without need for a large passive filter.

Thus if you have a decent HU or amp for the components, you will not need to calculate anything. likewise if you really don't care about the sound and the speakers are not distorting due to excessive bass, you will not need to calculate anything.