How Do I Adjust A Subwoofer For Best Sound?

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I'll switch the amp to sub on the cross over and or set them anywhere around 50-80 khz. Depends on the mids used and size
 
Your 6.5's will likley "roll off" at a certain freq, so a filter may not be necessary at all*.

What does the crossover control say?

If the 6.5's will do 60 Hz, then technically setting the sub crossover at 60 would be "correct", however, your ears will tell you what sounds good.
You really need the actual spec of that 6.5" speaker to use as a starting point, otherise, just set to what sounds good to you.

*Putting in a hardwired filter before the 6.5 could theoretically creat a "hole" btween the 6.5 response and the sub response.
That's not necessarily a deal killer, but something to be aware of.

Personally, I like a hard 60Hz hit. It's a good sound for "rock and roll", and some electronic music.

If the "phase" is cancelling out frequencies, you should be able to hear that, and set it accordingly.
I've never seen an adjustable phase switch. Like above, they are usually "in" or "180*".

As you move the sub further away (like in the trunk) the increased time it takes for the sound waves to get to your ears could cause it so sound "out of phase" with the other speakers, cancelling out some frequencies. It certainly could compensite for the sub being wired incorrectly, but that's not the actual intent.
 
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Lots of good information here, but I’ll add what I can to see if we can confuse you some more.

As @273 said, it won’t be a set it once and be done thing. You can get it close, but as you listen to different music, you might need to tweak it now and then, eventually you get it where it sounds good on almost any type of music you listen to.

First, a crossover is a circuit that sends low frequencies to the speakers that can handle that, and high frequencies to speakers that handle those. The crossover dial on your unit should actually be labeled low pass filter. It sets the frequency at where the subwoofer starts to quit working. I say starts to quit because it is not a switch, it is a slope, and the number represents where the slope starts. Some manufactures like shallow slopes, some manufactures like steeper slopes, and more advanced electronics allow you to adjust the slope. This one does not.

The reason for the filter is the same as you don’t want too many cooks in the kitchen. You don’t want the subwoofer and the speakers trying to reproduce the same frequencies or it starts to muddy the sound. That’s why others have said to listen to music and figure out where, your speakers start to get kind of shy in the bass. 80 Hz is really a very good starting point. 6 1/2 inch speakers are usually pretty good down to somewhere between 70 and 100. A lot depends on the speakers enclosure (your door cavities), and a lot depends on the room, (the vehicles interior). Whereas the speakers have a slope in the other direction, they don’t just stop working like a cliff, the response “rolls off”.

The Crossover (or Low pass filter) will set the point at where the subwoofer starts taking over reproducing lower frequencies. (It allows the low freq to pass the filter to the subs amp and speaker)

First, in your case, listen to the system without the subwoofer. Since the subwoofer is driven off the rear output of your system, whenever you adjust the front/rear fader control, it will affect the balance of bass to higher frequencies. I prefer a little more forward presentation because I go to see music with the musicians in front of me, and add just enough rear to make it sound a little more full. Some people like more in the rear (like our old-school cars when we had decent 6X9s in the back and crap up front). Figure out what you like first. Once you figure that out, this would be the one control that you probably don’t want to change too often, or take note of your settings so you can return. (you might be able to use this to your advantage later-if something is a little too bass heavy, you have the option to either adjust the Bass control on the head unit OR give a little Fader to the front)

Your door speakers will definitely cover the range of female voice frequencies. They will cover all but the very lowest range of male voices, James Earl Jones being the exception. That point is generally between about 80 and 100 Hz. That’s the point that human hearing is able to pinpoint where a sound is coming from, below that we are less sensitive to direction. You don’t want the subwoofer contributing to directional cues, so you won't want to be to the higher end of the scale. Localization AND cooks in the kitchen- both bad.

At this point, it’s helpful to have somebody help you. Starting with subwoofer Volume at MIN, Crossover @ 80, and Phase at 0. Listen to a good recording of the type of music you will mostly listen to. If this is a vehicle that has air conditioning and you will usually have the windows up, then listen with the windows up and the AC running. Have your helper bring the woofer level Volume up from its lowest setting. Stop when you get a good balance between enough bass, yet not overbearing. Again, some back-and-forth might be necessary.
Now have your helper quickly spin the phase from 0 to 180. Do you notice more bass at 0 or 180? It will probably be somewhat subtle because this will affect the area where the sub and speakers overlap (they are both reproducing the same frequencies. If there’s more bass at zero, the “ideal” setting will between 0 and 90. If there’s more at 180, then ideal will be on the higher side.

If there was enough added bass, you may want to tweak the bass volume setting again. Get that leveled again, and see if you can discern a difference as someone moves the Phase within the 90° range you previously determined. It starts to get more and more subtle, but you are looking for the spot where it “just blends” or sounds “right”.

If this is a windows down vehicle, this is all mostly moot, because all the wind noise is going to mask most of these settings. Set it all with the engine running, but know that you are going to probably add a lot of bass later, but once you get the system to overcome the wind noise, stop the truck leaving the system playing at the volume and bass level you had, and make sure the system and or sub isn't all distorted sounding. If everything is distorted, bring it down to where it sounds clean, if just the bass is distorted, lower it level to the clean point, and that's about the limit of where you want to run it.

As said, over the next few days or even weeks, you might find yourself doing minor tweaks as you listen to different music and/or sources.

I think I speak for anyone here- Feel free to PM if I (or we) can offer any additional info.
 
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Thanks for all the help, yall. It's much appreciated, even though I don't understand 90% or more of it. Just to make it clear what I have, here are the door speakers:

Here is the head unit:

Here is the subwoofer:

I also have this I "could" add to the front speakers, but looking at the specs for this and the head unit, I don't think there's anything to gain. The head unit is rated at 40w x 4 and the Kicker is rated at 30w x 2. So I think the Kicker won't do any good, unless somehow the head unit and the Kicker are rated differently.

Lastly, here's a pictuer of the subwoofer and the small Kicker amps controls:
The subwoofer:
SUBWOOFER.jpg



And the Kicker amp. Any help is greatly appreciated.
KICKER AMP.jpg
 
The more I drive the truck and listen to it....although it sounds a LOT better than those two 6 x 9s in the those tiny boxes, I'm thinking the front speakers are over powered by the subwoofer.
 
The more I drive the truck and listen to it....although it sounds a LOT better than those two 6 x 9s in the those tiny boxes, I'm thinking the front speakers are over powered by the subwoofer.
A separate amp is almost alway gonna be better and louder than the head unit built in amp,

It’s relatively way easier to get volume out of subs than the front end, especially if powering the front from the deck.
 
Head units are usually rated at peak power, (read that as downhill with a good tailwind) whereas an actual amp is rated as continuous, or RMS.
Also, there are different ways to get to 40 watts if you know ohms law. Power (in watts) is achieved from Amps X Volts. You can achieve a lot of voltage with a little IC chip, but higher voltage won't control a speaker as well. 2 Amps X 20 Volts = 40 watts
But 5 Amps X 8 Volts also = 40 Watts.
Amperage gets the work done. A fast and furious turbo Toyota may have 400 horsepower, but you ain't gonna put a 24' trailer on it. A speaker is a load.
 
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The 30 Watt RMS Kicker would walk all over the 40 Watt peak head unit.
Picture shows 2 sets of RCA outputs on the back. The specs say 1 pair of outputs for rear. Maybe updated? If you have 2 sets of outs, Is the 2nd set for a sub, or for fronts?
If it is a front out, set the Input Level of the Kicker to Lo, If you are using the speaker outs of the head unit, set that to Hi.

If it only has 1 RCA output ( rear) I would consider using a couple simple "Y-cords" on the output, run both the Kicker and Blaupunkt off that, but still run the Kicker to the front speakers. Then get the 2 front speakers blended with the sub til it sounded good. Then add the rear speakers off the front output of the head unit as some fill. The clincher here would be that the Front/Rear Fader control on the head unit would be backwards. Other than operation, there's nothing wrong with that, it's just stereo, there's only 2 audio channels-Left and Right.
OR
Forego Fader control, run both front and rear speakers on the Kicker. Tweak the system with the gains (or Vol) on the amps, and the Crossover & Phase to get it as good as you can. Leave the Bas Boost set to zero on the Kicker. Try different musics and conditions until you get it "right".
Then, just use Volume, Balance, (L-R), Bass, & Treble on the head unit.
 
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I'm old school. Keep adding the sub until rust falls out of the rockers and quarter panels. Add a bit more for exhaust rattle, then a touch for the sound of a few bolts loosening. Then turn it down a bit. If a window blows out during the testing you've gone a bit far, so mark the dial so when the new glass is in, you know your maximum.
 
The 30 Watt RMS Kicker would walk all over the 40 Watt peak head unit.
Picture shows 2 sets of RCA outputs on the back. The specs say 1 pair of outputs for rear. Maybe updated? If you have 2 sets of outs, Is the 2nd set for a sub, or for fronts?
If it is a front out, set the Input Level of the Kicker to Lo, If you are using the speaker outs of the head unit, set that to Hi.

If it only has 1 RCA output ( rear) I would consider using a couple simple "Y-cords" on the output, run both the Kicker and Blaupunkt off that, but still run the Kicker to the front speakers. Then get the 2 front speakers blended with the sub til it sounded good. Then add the rear speakers off the front output of the head unit as some fill. The clincher here would be that the Front/Rear Fader control on the head unit would be backwards. Other than operation, there's nothing wrong with that, it's just stereo, there's only 2 audio channels-Left and Right.
OR
Forego Fader control, run both front and rear speakers on the Kicker. Tweak the system with the gains (or Vol) on the amps, and the Crossover & Phase to get it as good as you can. Leave the Bas Boost set to zero on the Kicker. Try different musics and conditions until you get it "right".
Then, just use Volume, Balance, (L-R), Bass, & Treble on the head unit.
The head unit has 2 RCA outputs as does the sub and the small Kicker amp. I'll have to add a low level adapter to the front side of the head unit to add that amp. If you think the amp will power the front speakers better than the head unit, then it might be worth doing. Thanks for all the advice.
 
I'm old school. Keep adding the sub until rust falls out of the rockers and quarter panels. Add a bit more for exhaust rattle, then a touch for the sound of a few bolts loosening. Then turn it down a bit. If a window blows out during the testing you've gone a bit far, so mark the dial so when the new glass is in, you know your maximum.
The sub has nice bass, but it's not that powerful. LOL
 
IMHO you got 40 watts to some entry level speakers. You can’t expect much. Your stereo should sound good without the subs.
 
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IMHO you got 40 watts to some entry level speakers. You can’t expect much. Your stereo should sound good with without the subs.
I have the same head unit in the Valiant and it sounds really good. It's also insulated with Killmat. The truck is a truck. Old and loud. As for the speakers, they are all I can afford. Feel free to send me a better pair.
 
When I say one out or two outs, I meant pairs. One out meaning a left & right (white/red) for rears. Two outs- apair for front and a pair for rear. I’m sorry.
 
Those 6.5's have impressive specs-

  • handles up to 30 watts RMS (300 watts peak power)
  • impedance: 4 ohms
  • frequency response: 40-22,000 Hz
  • sensitivity: 90 dB

Hard to find 40 Hz response in something that small.
However, the magnet looks tiny.

I've found "sound guy's intuition" judging of speaker by the magnet size to be basically true. Bigger magnet = better speaker.
The same can be said for amplifier power ratings.

Look at the phisical size (and weight) of that head unit...and consider what all else it has to do besides amplify.
...and it's rated at 4 channels of 40 watts or 160 watts total?
Then look at that seperate amp, it's size and weight (and cooling fins)...but "only" rated at 30 watts by 2 channels or 60 watts total.
Something doesn't add up.
 
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I've found "sound guy's intuation" judging of speaker by the magnet size to be basically true bigger magnet = better speaker.
The same can be said for amplifier power ratings.


I always followed that rule too, but I just got a new set of subs with neodyum magnets on them. Each sub weighs only a couple pounds and the magnets are smaller than a hockey puck. They hit harder than the JL's I used to run 20 years ago. I really wasn't expecting much out of them, based on magnet size, but with a 300x2 amp pushing them, it's usually turned down most of the way.
 
The speakers sensitivity is important spec especially for fronts that generally can't handle crazy power which is a problem since loudness (db) and an amps wattaged ain't linear.

Loudness is rated in db, 3 db is considered a barely noticeable change in volume 6 db is a very noticeable change and 10 db is double the loudness. It takes 10 times the wattage to double the loudness (10 db)
and it takes doubling the wattage to move up 3 db and 4 times to move up 6 db.

So it's a lot easier to gain loudness through speaker sensitivity a 95 db speaker gonna be twice aa loud as an 85 db with any given wattage.

One good thing about they way wattage works say you got a 50 to an 150 watt amp on the front to double the loudness you would need 500-1500 watts for most people be insanely over kill.
 
Adding speakers does a similar thing, generally you only do that with subs multiple fronts add phasing issues. Basically getting 10 db louder can also be done by 10 times the speakers and every 3 db by doubling the speakers adding a port also gives 3 db. So going from one seal sub to 4 subs in a ported box almost doubles the loudness by gaining 9 dbs.


Then you start adding in the effect of distance, Double the distance cuts volume by 6 db cut distance in half gain 6 db, you see why concerts have insane systems.
.
 
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I thought 90 was pretty effecient on those car speakers.
 
I thought 90 was pretty effecient on those car speakers.
A sensitivity of 90 db, is 90 db at 1 meter with 1 watt, so 1 meter basically listening position in a car, going 10 x to 10 watts gives you a 100 db, going 10 x again a 100 watts equals 110 db, can't really go up another 10x's and doubling to 180 watts only gives you a just noticeable change in volume.
 
A cursory glance at Crutchfield shows 90dB is the mid to higher end of sensitivity for 6.5" speakers they have available.

They are fine, but I wouldn't throw 300 watts at them with that smallish magnet.

With that 90dB sensitivity- means they will be efficient at lower wattage anyway.
 
oops, those speakers aren't coaxials, so yy1 is right, low freq. is 40hz. these speakers aren't designed really to run with a subwoofer, thats why the frequency response is so wide. i would still start around 80hz and probably work up the scale to find the best response.

if the bass is too loud just turn down the amp a number or so until it blends nicely. hope this helps.
 
oops, those speakers aren't coaxials, so yy1 is right, low freq. is 40hz. these speakers aren't designed really to run with a subwoofer, thats why the frequency response is so wide. i would still start around 80hz and probably work up the scale to find the best response.

if the bass is too loud just turn down the amp a number or so until it blends nicely. hope this helps.
The speakers in my doors are coaxials. That is, unless I don't know the definition. lol
 
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