Amp settings, general rule of thumb?

[MillerSHO 10+ year member]

Wanted to know if there were some starting points for the different settings for a dedicated sub amp.

So far what I've read:

Low pass filter: 80-120hz depending on taste and how much midbass your fronts put out.

Subsonic filter: 5hz below what your box is tuned for.

Bass EQ setting: keep to 0

Avoid using kind of "bass gains" on your HU, pass through to amp and let amp adjustments do the work.

Does this sound correct?

Setup in question is a MRX-M50 amp and JL W3 2ohm with JL spec ported box.

Thanks

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[butterMilk 10+ year member]

close enough, not sure bout the subsonic but for the low pass I personally don't go over 80

 

[TaylorFade 10+ year member]

You can make EQ adjustments or sub level adjustments. The "bass gain" to avoid is the "loudness" setting. Everyting else looks good.

I assume you've searched on how to set the gain correctly?

 

[eddie_93 10+ year member]

You can make EQ adjustments or sub level adjustments. The "bass gain" to avoid is the "loudness" setting. Everyting else looks good.
I assume you've searched on how to set the gain correctly?

Question on this. I've read that the "subwoofer level" should be maxed out, on my Kenwood HU the subwoofer level goes from -15 to +15. Is this true? Then the "bass level" and "bass boost" should be set to 0 or is it generally ok to add a small amount?

 

[TaylorFade 10+ year member]

Question on this. I've read that the "subwoofer level" should be maxed out, on my Kenwood HU the subwoofer level goes from -15 to +15. Is this true? Then the "bass level" and "bass boost" should be set to 0 or is it generally ok to add a small amount?

The bass level, I'm assuming, is your EQ. It's ok to use EQ as long as you're not boosting the crap out of the frequencies. You want to try to cut peaks instead of boosting dips in the response.

Bass boost in any form should be avoided if possible. It's usually just a boost centered around 45hz anyway. No thanks.

Some HU's sub level is just an attentuation. Meaning that max level is basically what the HU pre out voltage is. So, if your HU is a 4v, then +15 on your sub level is 4v. Not all HU are like this though and I can't tell you if yours is. What I'd do is set it up at 0db and have the +/- 15 as headroom.

 

[MillerSHO 10+ year member]

You can make EQ adjustments or sub level adjustments. The "bass gain" to avoid is the "loudness" setting. Everyting else looks good.
I assume you've searched on how to set the gain correctly?

I believe so.

My confusion comes with the subwoofer setting on the kenwood HU, should it be at -15, 0 or +15?

If I could get this pinned down I feel like I can move on to making sure the gains are correct but I need the starting point figured out first.

 

[MillerSHO 10+ year member]

close enough, not sure bout the subsonic but for the low pass I personally don't go over 80

I can't seem to find people agreeing on the range.

80hz-120hz seems high, I was more happy at 60hz-70hz.

I have decent midbass with hertz 6.5 and rear 6x9's though so I don't know if that's the difference.

 

[butterMilk 10+ year member]

When I ran the auto tune on my HU, it set the low pass at 80hz. Not saying that the HU know exactly what its doing, but 80 seems to be a number that lots of ppl use. its personal preference right.

 

[maylar 10+ year member]

The +15 setting would be maximum level. Most of us like to leave a bit of adjustment to allow bumping songs that were recorded with low bass, so I'd pick about +10.

The LPF would depend on the midbass of your main speakers. Some people like to HP the mids at 120 so they can crank some power to them and let the subs handle there and below. If your main speakers can play down to 65 that's great. You can run the subs lower and not get blown out of the car with midbass from the subs. 60-70 is where I like it too.

 

[cdc351jeferson 10+ year member]

i like to use a lc-1 as my sub level . mine on deck is at 0 and i just use the lc-1 . amp was set with dd1 works out good for me

 

[MillerSHO 10+ year member]

Setting the subsonic filter to to 5hz below what the box was tuned for appears to not have enough "feel" in the bass note.

My subsonic filter goes from 5hz to 30hz and my box is supposedly tuned to 35hz.

Setting subsonic filter around 25hz seems to give me the grunt down low, settings for 30hz just wasn't enough.

I checked the settings on my fronts and 90hz is actually where the high pass is set and my sub is set for 70hz on low pass.

My rear 6x9's are set to 70hz for high pass.

Think I have all the HZ ranges covered at this point and the bass sounds clean.