Boosting Bass by Gain versus EQ

[BigED]

My system is composed of a Kicker IX-405D amp running 115rms to one set of Focal Polykevlar 165K2s and 200rms to a JL Audio 10w3-2 stealhbox. I'm not running any rearfill.

I am trying to tweak my system to sound better. I don't have a separate EQ component, so I'm wondering what the best way to set it is.

My CD headunit has a loudness button, bass boost, and treble boost. My amp has a crossover frequency switch for the sub (70hz or 110hz - currently set at 70hz) and it has a Bass and a Gain Knob for the sub. It also has a treble and gain knob for main component speakers.

My question is - do I want everything to come out at a flat frequency curve from the CD deck and then tweak the amp controls, or do I want to do everything from the Deck. I can get the boom I want, but I'm looking for tighter midrange/midbass. The mid speakers in my component set are 6.5 inches and are in the door (running freeair, not sealed). I'm looking for more tightness.

Also, when I adjust the bass to the sub with the amp controls, do I want to raise the bass knob and raise the bass by EQ, or raise the gain knob and raise it by gain. I'm confused because both of them would raise bass. (I'm looking for tight over big boom)

[Reverend_Ezekiel]

It's best to keep the gain as low as you can go and still produce the sound you want! The course of action is, of course, to buy a seperate EQ. If you don't have one, then you'll have to make due with what you have. Fine tweak the EQ until you like the sound. Everyone has different tastes, it just takes time and patience.

If you want SQ, then tuning is made easier by listening to music in concert. Listen to a song at a concert, then try to tweak your car's system to sound as close to that concert sound as possible.

You sould use both the amp controls and the HU controls to tweak the sound of yokur system.

[Backfire]

Many "bass knobs" are like a single band parametric EQ. When you adjust them, you put a "hump" in the signal centered around a certain frequency, normally around 40Hz. If you adjust the gain, you are increasing the level of the all frequencies on that channal. If you have a high voltage head unit, it allows you to set your gains lower, which helps to reduce audible noise, while still playing at high volume levels. So, if you use the bass knob, the sub will play louder around the center frequency of the boost. If you use the gain, the sub will play louder on all frequencies.

Another criteria to determine which component to use is the quality of the EQ/crossover. If the headunit has built in crossovers, but are 1/6 octave, this will give you a gradual roll off. If the crossover is 1/12 or 1/18 octave, you will have a more rapid rolloff. The same is true for eq settings, some are very sharp and affect only a small range of frequencies while others offer a broader adjustment. The best choice would depend on what your system needs and what your components are capable of. Check in your owners manuals the specs on the eq adjustments to see how each is configured.

As for the tightness of the midrange speaker, what frequency are they crossed over at? This will affect the sound quality. Also, what have you done to your door panel? Any sound deadening or sealing? I used sound deadening on the entire door, and made sure the speaker baffle was sealed well to the door. This made a decent improvement in the response of my Boston RM6's. It is still a free air setup, but it does isolate the back waves from the cabin somewhat and helped to tighten up the response. A small, sealed enclosure would work wonders, but that is pretty envolved in our doors. When I had the RM6's in another car, I made sealed kickpanel enclosures for them, and they weren't half bad played as full range. But in the doors, they couldn't play as "energetically" as when sealed. I had to use a higher cutoff frequency and use the sub to make up for the midbass loss. Not ideal, but I wasn't willing to give up my footwells for speaker enclosures.

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by Backfire:
Many "bass knobs" are like a single band parametric EQ. When you adjust them, you put a "hump" in the signal centered around a certain frequency, normally around 40Hz. If you adjust the gain, you are increasing the level of the all frequencies on that channal. If you have a high voltage head unit, it allows you to set your gains lower, which helps to reduce audible noise, while still playing at high volume levels. So, if you use the bass knob, the sub will play louder around the center frequency of the boost. If you use the gain, the sub will play louder on all frequencies.

Another criteria to determine which component to use is the quality of the EQ/crossover. If the headunit has built in crossovers, but are 1/6 octave, this will give you a gradual roll off. If the crossover is 1/12 or 1/18 octave, you will have a more rapid rolloff. The same is true for eq settings, some are very sharp and affect only a small range of frequencies while others offer a broader adjustment. The best choice would depend on what your system needs and what your components are capable of. Check in your owners manuals the specs on the eq adjustments to see how each is configured.<hr></blockquote>
exactly.

[img]smile.gif[/img]

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by Backfire:
Many "bass knobs" are like a single band parametric EQ. When you adjust them, you put a "hump" in the signal centered around a certain frequency, normally around 40Hz. If you adjust the gain, you are increasing the level of the all frequencies on that channal. If you have a high voltage head unit, it allows you to set your gains lower, which helps to reduce audible noise, while still playing at high volume levels. So, if you use the bass knob, the sub will play louder around the center frequency of the boost. If you use the gain, the sub will play louder on all frequencies.

Another criteria to determine which component to use is the quality of the EQ/crossover. If the headunit has built in crossovers, but are 1/6 octave, this will give you a gradual roll off. If the crossover is 1/12 or 1/18 octave, you will have a more rapid rolloff. The same is true for eq settings, some are very sharp and affect only a small range of frequencies while others offer a broader adjustment. The best choice would depend on what your system needs and what your components are capable of. Check in your owners manuals the specs on the eq adjustments to see how each is configured.<hr></blockquote>
exactly.

[img]smile.gif[/img]

[TokFan]

I would put the bass/treble knobs on the head unit "flat" and then adjust the gain to where you feel it sounds as good as it can get. Then if you have to you can fine-tune the sound with the HU.

If we are going to get technical it is better to use an EQ (or the bas/trebble knobs) as little as possible. If you for example (like a lot of people) turn the bas knob to max you are going to get a phase shift in your sound (the bass frequencies will "lag behind" the rest of the sound).