hades281

I'm like others who think that the base stereo has muddy mids and lows. I'd like to clean that up. My goal is not to have a loud, powerful sub. I just want clean, high fidelity balanced audio. My '08 IS250 base stereo was satisfactory in this regard -- so you can understand what i'm after.

There is some thought that the subwoofer is to blame -- I havent unplugged it to see how things sound with it disconnected, but will do so.

If it is indeed the sub , here is the tentaive plan... Ideas, hardware suggestions?

1) Replace the factory sub with a shallow depth sub of the same diameter in the rear deck. I'm not interested in a sub box, and I don't want something overly powerful.
2) Use an inline crossover to the sub, so I can cut out mid frequencies to the subwoofer.
3) Use the factory amp to drive the sub.
4) Build harnesses and connectors to interface with the factory wiring so that there is no splicing of the factory harness.

Bass Mech

this will be a total waste of time and money..
the reason is because what you have here is whats called an infinite baffle subwoofer. it means that the sub itself suspension is for simplicity a spring.
a sub in an enclosure uses the air pressure in the box either sealed or ported as part of its mechanical design to control the movement of the speaker.
in an IB setup the sub itself does this as part of it's design.
the problem with an IB sub is 2 fold.
1 the spring or (compliance of the sub) needs to be a progressive one. in other words the suspension gets stiffer exponentially as the movement of the sub gets greater.
when you play rap music you also end up with bass tones that are near the resonant frequency of the sub itself. this causes it to over extend its mechanical limits making it sound distorted.
the other problem is that the trunk of a car is a difficult area to isolate the rear waves from the front waves and they will eventually cancel each other out.
so it is difficult to get any really low bass frequencies from this type of setup.

if you install a thin mount sub that was designed to be put in a small box your going to make the problem even worse because a shallow mount sub designed for a small box will have a fairly compliant (loose) suspension because it is going to rely on a fairly high pressure box. and the magnet or motor is going to be a high efficiency design because the additional motor strength is needed in a smaller box.
it will also have a fairly heavy weight cone.

taking this sub and installing it into a trunk which provides no spring or resistance and allowing it to play in free air will result in a sub that has basically no bass in the mid bass range and barely any low bass with a lot of mechanical noise because with a heavy weight cone it will have almost no ability to play the higher bass notes and will resonate at a low frequency well below the range that be heard out of an infinite baffle setup.

hades281

Hey Bass Mech,

Thanks for the insight! I saw your other post where you would consider putting together a 'DIY Kit' for us to clean up the sound in these cars. I'm very curious to see what you would come up with.

I wish there was an easy, simple to clean up the mids. Many people are describing the non-ML system as either "bass heavy" or "muddy." I agree with the muddy part and this is my primary complaint. I tend to think that the software is to blame; I wonder if we had control of the subwoofer crossover setting if that would allow us to restore a lot of clarity to the system. Since we don't, I wonder about adding a low-pass filter on the subwoofer signal wire, so it is only attempting to reproduce the lower frequencies. Does that sound plausible? Even with the lousy factory sub, at least it shouldn't sound muddy. It's bass hits may not impress but the sound should at least be staged well and clear.

Loe

I find the non-ML subwoofer very unrefined and lacks a warm bass response. I too would be interesting in a DIY set-up with a hideaway sub enclosure, perhaps something similar to this:

Dunhill421

zhifan1

Can you point me to the harness for the sub? Is it the same as the door speakers' harness? Thinking of doing the same thing... thank you.