Lack of bass after front speaker install

[joemac]

I've got a Kenwood KDC-MVP8025 on the stock OEM non-Bose speakers in a "02 CC with center console. Just last week I installed a pair of Infinity 6002si in the front doors.

 

The speakers sound absolutely awesome, great fullness (bass) when you have your head down toward the drink holder. Or closer to direct alignment of the speakers. I notice that as you sit upright going toward a normal driving position the bass seems to greatly disappear. It's like a night and day difference.

 

I'm using the speaker wiring adapters that came with the speakers. One end plugs into the GM harness, the other side positive and negative plugs into the speaker. Since the speaker side of the connection uses a wide plug for the positive and a narrow plug for the negative it’s pretty much idiot proof. I highly doubt there's a phase the speakers sound awesome the more inline your ears are between the speakers. Also in moving the balance from full left or to full right doesn't produce more bass as I would expect if there was a phasing problem.

 

Any ideas on the large difference in perceived bass and fullness when sitting in a normal driving position? It's hard to believe difference is this dramatic.

 

I used the supplied foam to encompass the rear backing of the speaker plate to ensure a good seal on the door panel. Could the lack of sealing on the speaker adapter legs that mount through the door cause this major of a difference. I noticed the OEM plastic speaker retainers/mounting had foam that encompassed the entire speaker back side and the three mounting legs where they poke through the sheet metal of the door. The aftermarket adapters didn't have this foam present on the mounting legs Don't know if this would cause any issue. Again moving your ears closer to the speakers nets a much more rich and full base response. Issue is best summarized as like the direction of bass from these speakers is more focused rather than spread out over a larger area. The mid and high coming from these speakers sound fine. I did leave the OEM tweeters plugged in. I think I'm gonna opt to unplug and not use the OEM tweeters upon getting into the door panel again.

 

I've ordered a set of Kenwood KFC-1669S 6.5". I'm gonna use this different brand/model speakers and replace the Infinity's to see if there's any difference.

 

Any ideas, opinions, and guesses are appreciated.

[SteveSierra]

I've got a Kenwood KDC-MVP8025 on the stock OEM non-Bose speakers in a "02 CC with center console.  Just last week I installed a pair of Infinity 6002si in the front doors.

 

The speakers sound absolutely awesome, great fullness (bass) when you have your head down toward the drink holder.  Or closer to direct alignment of the speakers.  I notice that as  you sit upright going toward a normal driving position the bass seems to greatly disappear.  It's like a night and day difference. 

 

I'm using the speaker wiring adapters that came with the speakers.  One end plugs into the GM harness, the other side positive and negative plugs into the speaker.  Since the speaker side of the connection uses a wide plug for the positive and a narrow plug for the negative it’s pretty much idiot proof.  I highly doubt there's a phase the speakers sound awesome the more inline your ears are between the speakers.  Also in moving the balance from full left or to full right doesn't produce more bass as I would expect if there was a phasing problem.

 

Any ideas on the large difference in perceived bass and fullness when sitting in a normal driving position? It's hard to believe difference is this dramatic.

 

I used the supplied foam to encompass the rear backing of the speaker plate to ensure a good seal on the door panel.  Could the lack of sealing on the speaker adapter legs that mount through the door cause this major of a difference.  I noticed the OEM plastic speaker retainers/mounting had foam that encompassed the entire speaker back side and the three mounting legs where they poke through the sheet metal of the door.  The aftermarket adapters didn't have this foam present on the mounting legs  Don't know if this would cause any issue.  Again moving your ears closer to the speakers nets a much more rich and full base response.  Issue is best summarized as like the direction of bass from these speakers is more focused rather than spread out over a larger area.  The mid and high coming from these speakers sound fine.  I did leave the OEM tweeters plugged in.  I think I'm gonna opt to unplug and not use the OEM tweeters upon getting into the door panel again.

 

I've ordered a set of Kenwood KFC-1669S 6.5".  I'm gonna use this different brand/model speakers and replace the Infinity's to see if there's any difference.

 

Any ideas, opinions, and guesses are appreciated.

 

<{POST_SNAPBACK}>

 

 

The Kenwood speakers, believe it or not, will most likely sound better. A starting range of 58 Hz(the Infinitys) is not low enough. Something in the 25-30 Hz - 22,000 Hz range would be ideal. The Kenwood speakers start at 35Hz. Pioneer makes a 6 1/2" speaker that starts around 28Hz. You also really need to boost the signal with an amplifier. Aftermarket stereos can sound, in some cases, weaker than the factory stereo without an amp. If you are using the factory amp, that will help only minimally. You really need to boost those speakers with something like a decent 60x4 amp. I had a similar HU, Pioneer 6 3/4 front speakers, and a JL Audio 10" sub in a homemade MDF downfiring box in my old 2500HD EC. With 2 channels of the amp going to the front speakers and 2 channels going to the sub, it was waaaaaaaay more than bassy enough no matter what direction my noggin was in LOL.

For a budget amp, I would suggest the Kenwood KAC-8402. It's only 250 bucks, and that's basically the amp I used in my truck. Leaving the OEM tweeters plugged in won't make a big difference. I left them plugged in in the HD.

[Wingnut]

Yup, what he said.

 

The factory speakers are designed to play the full spectrum of sound, so you get highs, mids, and lows out of the door speakers.

 

Aftermarket speakers are purpose designed to play very specific frequency ranges, so you will lose bass when installing aftermarket mids/tweets unless you add a subwoofer.

 

Not sure about going as low as 25 hz with midrange speakers though. Humans can only normally hear down to 20 hz, so I would think that a sub should be handling anything below about....Oh...60hz or so. That's just off the top of my head though, I don't remember where mine is set to crossover.

[100R1]

I would check the Polarity of the speaker wiring from the head unit to each speaker. If only 1 speaker is wired incorrect your bass responce will greatly be reduced.

 

Do you have a factory amp and sub ?

 

The speakers you installed have a freg range of 58-21,000 HZ AND A sensitivity of 92 DB

 

but we dont know where they roll off at. you may just need a larger amp to push the power in the lower freq. DIfferent mfg speakers have different effecency at different octaves/range. Yours probally just need more juice.

 

How many watts are you pushing to the speakers ? (@ what Ohm?)

 

If you don't have a sub you need to add one to reinforce the lows below 60 HZ

 

almost all quality door speakers cut off around 60 HZ and it's really hard to get GOOD low sound below 60 HZ from door speakers.

 

You have the foam surround baffles behind the speakers this should help with a tight sounding bass (thats a good thing), but the doors just don't go down low enough to rattle your cage.

[mmmikkke]

I second the polarity issue. I submit that both your front speakers are out of phase with your rear speakers.

 

I replaced all the factory speakers, and noticed that the factory speaker has the "+" on the opposite side as the aftermarket Pioneers that I installed.

 

When viewing the Pioneer speaker as it sat face down on the table, the negative was on the left and the positive was on the right. The factory speakers were the opposite of this.

 

Maybe your adaptor ignored this subtle difference.

[masterp2]

Certainly isolate the fronts from the rear, but I think you may find the same thing. Notwithstanding phase problems between fron and rear, the answer may be "this is normal". While possible for some door drivers to create some significant "midbass", they will not provide significant bass output, 10-60HZ. Physics. But this is not an acoustics tutorial. Much of what we consider bass is mid-bass, 60HZ and up. It is very audible, moreso than lo bass.

 

When using a door to house a driver, we are trying to use something that is not designed for acoustic output, as the only place with some depth. But a door is far from being a good steward of acoustic performance. In the bass region, a sealed enclosure's effectiveness depends wholly on its ability to absorb/cancel the backwave (keep it from getting out). If the backwave is finding its way out of the door panel, it will cancel the frontwave. We know that doors are notoriously leaky and resonant, etc. You can minimize this by locating drivers by your ears, as in your head between your legs, making the frontwave "less diffuse " to your ears than the backwave. (BTW your observation of increased performance proves that your fronts are in-phase.) The problem can be improved by making your door a better sealed enclosure, or at least infinite baffle. Pull off the panel, seal up any holes you can (except the drain holes on the bottom), deaden the skins with dynamat. put some fiberglass batting or acoustic foam between the door panel and inner skin. This is huge, the foam absorbs much of the backwave that tries to to leak back into the listening environment. Just remember, any backwave that mixes with the frontwave is analogous to wiring 2 lo-freq frivers out of phase.

 

The BEST solution is to lo pass the doors, around 60HZ, and let a dedicated sub, in a true sealed enclosure, handle the challenging lower octaves. Your mids will love you for it also, they really do not like trying to handle lo bass. You will get much louder volumes out of them without distortion, and will be less likely to blow them. I would never cross door mids lower than 50, no matter the rating or "specs" ha ha. Nor would I ever put a driver in there trying to get "bass". Trash is all you will get, though a few hacks will mistake that for bass.

 

A single dedicated 8" in a .75 cf mdf enclosure will make the system come "alive". Of course 2-10's will be beautiful. I build and sell CC cabinets with 2-10's behind the back seat, that has flat response to 5HZ. It is shocking how good they make the mids sound.

[SlamminL5s]

you know with my personal experience with kenwood they sound pretty much like stock.... and their subs blow easy... i would bring that stuff back and get some power acoustik or jl

 

p.s i had a complete KFC set up in my moms cavy... didnt last more then 3 months

[joemac]

Summary of the scenario:

 

Kenwood head unit, all OEM speakers. Full range normal GM muddy sound. Bass output perceived as normal.

 

Only change install front pair of Infinity speakers. Serious loss of bass depending on seating position. Normal driving position = no bass. Move your head toward the center console bass response dramatically improves.

 

Got the Kenwoods in hand and went to town. First was to assure polarity was correct on the front Infinity speakers. Cruchfield was nice enough to assist with this on the phone. Polarity assured correct added addition foam sealing for the mounting of the front speakers. Then disconnected the OEM tweeters, will no longer use these.

 

Tested system, slight improvement believed from additional sealing.

 

Installed the Kenwoods in rear doors. Applied good amounts of foam sealing to the back side of the speaker.

 

Tested system, an incredible improvement. Bass is actually strong or strongest in the normal seating position or biased slightly toward the rear. No longer incurring the odd acoustical drop out of bass depending on seating position.

 

End result is very good. There's good full sound, much cleaner than the OEM setup. Speakers sound like they are powered moderately well.

 

Thanks for all the tips and suggestions.

 

Next addition will be a small powered sub like the Kenwood or Infinity offering.

 

Thanks again.

[Wingnut]

If you add a sub, you would like the Infinity's more up front.

 

Okay, maybe not, as everybody is different....But I sure would.

[SlamminL5s]

Infinity is a really good brand... their subs slam, amps are pretty good, speakers loud and clear and last long, good crossovers... i would rate them 9 outta 10