Are amp filters less important with a DSP headunit??

[LoudSound]

Hello guys, my 2nd post. I'm pretty much a total noob at caraudio so please bare with me. Trying to gather info before I buy an amp for my 4 front speakers.

I don't see why I Need to use redundant filters that try to accomplish the same task on both devices. In my understanding, I must have an idea of how I'm gonna need filters set on a particular speaker and the headunit filters should be paired with amp filters to create bandpass type filter but shouldn't be used redundantly. Am I correct?

in other words, I shouldn't have 100hz hpf set on the headunit and 100hz hpf set on the amp? right? my "mentor" is telling me to get an amp with "good" filters but I'm not sure what "good" filters are. This is just for a 2way front stage I'm building. Allz I gotta do is set hpf on the mids at like 100-200hz depends how loud I wanna play them, possibly not even use LPF because they play to 6-7k.. and just set hpf on the HU for the tweeter at like 6khz, should be good to go. the tweeters have a built in 4.5khz 2nd octave crosover, so that'll act as a 2nd wall against tweets playing mids, and destroying themselves.

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[LosIsATool 5,000+ posts]

You will bypass all amp filters when using a DSP.

 

[ilikeradios 10+ year member]

You will bypass all amp filters when using a DSP.

Yes this

I set all my amps to full output and control all crossovers at the Headunit / DSP

 

[trumpet 5,000+ posts]

I don't see why I Need to use redundant filters that try to accomplish the same task on both devices. In my understanding, I must have an idea of how I'm gonna need filters set on a particular speaker and the headunit filters should be paired with amp filters to create bandpass type filter but shouldn't be used redundantly. Am I correct?
in other words, I shouldn't have 100hz hpf set on the headunit and 100hz hpf set on the amp? right? my "mentor" is telling me to get an amp with "good" filters but I'm not sure what "good" filters are. This is just for a 2way front stage I'm building. Allz I gotta do is set hpf on the mids at like 100-200hz depends how loud I wanna play them, possibly not even use LPF because they play to 6-7k.. and just set hpf on the HU for the tweeter at like 6khz, should be good to go. the tweeters have a built in 4.5khz 2nd octave crosover, so that'll act as a 2nd wall against tweets playing mids, and destroying themselves.

Most full range car amplifiers have simple 2nd order, or 12 dB/octave, filters. That's standard. "Better" crossover filters are, in my mind, more flexible than the standard FULL, LPF, HPF selectable option with a wider range than, say, 50 Hz - 250 Hz. 3rd or 4th order slopes will protect speakers better in high power scenarios. That in itself isn't necessarily better, as there are always other factors to consider depending on how precise you want the results to be. The frequency range can be extended either with a knob(potentiometer) with a larger range or a multiplication switch(usually marked x10). The 50 Hz - 250 Hz range now can become 500 Hz - 2,500 Hz, for example.

Why does this stuff matter with a DSP? Amplifier crossovers can still be used for backup as protection when set outside the range specified with the DSP, stacking two 12 dB filters at the same frequency to make a 24 dB filter, or possibly in conjunction with a DSP's filter to create a bandpass filter.

Bandpass filters are both a High Pass Filter and a Low Pass Filter on the same channel. We see this often with subwoofers run in a ported box, so the low end is less likely to cause damage and the upper end is cut for better sound quality.

It's usually a good idea to set up a bandpass filter for mids because the upper end response normally gets colored by what we call breakup. A lot of component sets don't cut the top end of mid-woofers, but I believe this is a cost-cutting measure to hit a target price.

 

[LoudSound]

thank you for the answer boss, your explanation is much appreciated. So it's a matter of having the flexibility with your filters to get the results that you want..

midwoofer=midbass? aka speaker that plays to 200hz tops?

 

[trumpet 5,000+ posts]

thank you for the answer boss, your explanation is much appreciated. So it's a matter of having the flexibility with your filters to get the results that you want.. midwoofer=midbass? aka speaker that plays to 200hz tops?

Mid-woofer is the woofer in a typical two-way component set that plays something like 80 Hz to 4 kHz or so. Actual top end performance varies. Cutting the top end with a low pass filter is often desirable.

 

[LoudSound]

cool cool. definitely my mids will need to be cut off with LPF. I looked at the frequency response graph and the deebeez go way down after 5khz i guess that's the point where the speaker stops playing its optimal range.

 

[LosIsATool 5,000+ posts]

cool cool. definitely my mids will need to be cut off with LPF. I looked at the frequency response graph and the deebeez go way down after 5khz i guess that's the point where the speaker stops playing its optimal range.

A 6.5 shouldn't have to play over 2.5k. That's the point it starts to lose its dispersion

 

[LoudSound]

my speakers are 8inch faital pro's. I got them specifically because I've seen people running them in 2 ways and they sound great..

 

[wew lad 5,000+ posts]

Generally larger midrange drivers will begin breaking up and beaming at a lower frequency requiring a roll off earlier/lower in frequency than normal

 

[LosIsATool 5,000+ posts]

The only way to use a 8in in a 2 way is with a HLCD or a 3in that can cover the top end.