Question about crossovers, etc.

**jchahn** · 06-09-2005, 12:31 PM

Some people use their sound cards as a crossover by setting certain channels to a high pass or low pass filter.

My question is this: Some amps have a high pass or low pass toggle switch or filtering setting built into them. If you have such an amp is it necessary to do the crossover thing with the sound card? Couldn't you just send the full range to the amp and let the amp do the filtering in this case?

Great forum and great site btw.

**sdashiki** · 06-09-2005, 12:40 PM

You can either set the crossover at the amp
or
on the sound card (software, head unit etc)

Doing it on the amp is not the BEST idea because if you want to change it, you have to physically touch the amp and move a switch.

Though IT IS a good idea if your crossover is **** and in that case the amps built in is better.

Just dont do double redundancy, like have the crossover set at 80hz AND the amp set at 80hz, thats dumb.

**jchahn** · 06-09-2005, 12:54 PM

I suppose it's possible that the filter built into the amp might not be ideal for the speakers. Meaning that the pre-set frequency of the high pass filter might be too high or low for the specific speakers in the vehicle, or the low pass filter might be too high or low for the subs. I suppose using the sound card has more tweak-ability and customization in that sense, but I would think that the amp manufacturers would design the filters in the amps to work well with most car speakers and subs, after all, that's what they are designed for.

**Jahntassa** · 06-09-2005, 02:06 PM

If you have variable crossovers on the amp (meaning: you can set where the hi/low crossover point is, not just hi/low), then it's probably better to go with the amp. Only reason I say so: Processing time. You're using software (maybe hardware, depending on your soundcard) to do the processing. That means you're taking away from other functions. In the amp, it's all solid-state and doesn't really affect anything, so it would be more efficient to do in the amp.

However, it doesn't really matter, as both crossovers are before the actual amp stage, and the amplifier will potentially get the same signal.

As far as 'adjusting' the crossover points. You should only have to do that once, with the inital install, or any time you change your speakers. Adjusting the crossover point should NOT be something you're doing while flying down the road.

**SickVette** · 06-09-2005, 06:36 PM

Alot of good advice. But before you determine which xover to use you need to determine the specs of the xover. Your amp xover might be adjustable but it is only 6db per octave where the sound card is 18db per octave. The db per octave is a measurement of how many decibles the music drops at the xover frequency. The higher the number the better the xover. Essentially you want to use the xover that is more adjustable and has the higher db per octave.