Passive highpass filter for bass horn

[WaVeInFoRm]

Can one use a passive highpass filter for a tapped horn at say 30hz, or would the component be tooo large to have a 24db steep pass filter at such frequency

 

[woody]

Here is a crossover calculator for you to play with.

2-Way Crossover Designer / Calculator


But I think you will see the components will be huge and expensive
it would be a lot easier and cheaper to use an active filter.

 

[WaVeInFoRm]

Aye. Cheers

 

[AllenB]

For practical purposes it may be useful to put a part of a passive filter at the input to the amp.

 

[hottattoo]

Your cap and inductor values are going to be expensive if you buy high quality components. You would be better off going active IMHO sound wise.

 

[WaVeInFoRm]

Has anyone ever put a mini crossover, simply at line level between output of say a sound card, and phono imput on the amp, or does it have to be powered?

 

[AndrewT]

I used a pair of cascaded single pole RCRC filters at the input to the power amp driving a bass only speaker.

It sort of worked.
An active filter with low pass for the bass to mid crossover and with the horn/vented protection high pass added on will be far better.

If you are using opamps, then four opamps give you a 4pole LR low pass and a 4pole protection high pass.
Two dual opamps would be ideal.
moxlite Thread has lots of details showing how this can be done.

 

[AllenB]

I've done complex EQ passively in a single stage at line level. What makes it work is the response shape, not the method.

 

[zettairyouiki]

Filters for subwoofer use (low frequencies and high power) get expensive real fast because they need large components, especially if you want to do steep slopes. Totally possible in theory but it is not cost effective at all. Active crossovers or DSP are way cheaper.

 

[nigelwright7557]

I would not bother using a high pass crossover unless you are going to drive the speaker hard.