RomanTPA

I have used Polk Audio db840DVC 8-Inch Dual Voice Coil Subwoofer for 2 years now and it's amazing (amazon ~$50)

Rear speakers I have no clue what they are. sound stock

Apparently fronts were 6.5" 130w max cheap Polk duals.

buggs384

Question are you using the stock amp? Thanks all this information you're giving is very helpful

PRSUIT460

iTrader: (3)

And here I wish I had a non Nav non ML car so i'd have a separate climate control to be able to put in a nice aftermarket head unit easily..

RomanTPA

Stock amp is pushing everything

RomanTPA

I've seen many people replace indash disk changer with an aftermarket headunit that interfaces with existing nav screen and also adds DVD playback

RomanTPA

Kicker 40CS654 6.5" 2-way sound terrible.

Ordering Polk Audio DB651 6.5-Inch Coaxial Speakers. Previous owner had those installed front and back. Sounded great before Front-Driver speaker blew up.

How-to is finished. Check top of first page.

PRSUIT460

iTrader: (3)

I've seen that also but not sure about having 2 screens. We are going to put a scope on the output of the factory ML and see how much it drops off when the volume turns up. If it's not that bad we will keep and use the ML NAV unit.

yuri.ber

iTrader: (7)

Hi. My sub is starting to go and I wonder if I should replace it with the same Kicker COMP88 or something else.
I found this sub:
http://www.parts-express.com/bc-8ps2...-ohm--294-5917
Would you recommend this? It's 16 ohm but the rms power is 200w. Will this strain ml amp more than the kicker 8ohm sub?

RomanTPA

Check out front page for sub info

yuri.ber

iTrader: (7)

Yesteday I installed a Polk Audio sub. Boy have I forgotten it's a ***** to get to remove and install a sub. Anyway, first impressions: less distortion at low to moderate volume levels. Some distortion at high to max volumes but only on some songs, less bass intensive songs sound great. Also kicker sub I had in hit lower than this Polk Audio sub. Maybe I just have to brake it in. I'll update in a month or so.

buggs384

Roman how the sound on the new front speakers?

2KHarrier

Well, I hope I'm not asking a dumb question here, but I read through this entire thread, and I have to ask... I just bought a Polk Audio DB40DVC sub, on the recommendation of RomanTPA, and I just realized that in series, it will be rated at 8 ohms total. Should I be worried that it's so much lower than the rating of the amplifier?

rkw77080

Amplifier output signals work somewhat differently than a regular electrical load, such as a light bulb. Instead of drawing a steady current like a light bulb, the current delivered to a speaker varies according to the volume and frequency of the sound it will produce. So the impedance/resistance rating for a speaker is its “nominal” or something similar to the average value.

The LS430 ML amplifier specifies 8-ohm resistance for the door speakers, and 14.5-ohm for the subwoofer. If the replacement speaker’s resistance is too low, the amplifier will tend to overheat and a greater fraction of power is used up in the amplifier than is deliver to the speaker. At low output volume, this will not likely to harm the amplifier, but at sustained higher output volume, this can cause overheating and potentially damage the amplifier's output circuit.

The amplifier will deliver maximum power/volume to the speaker when the speaker impedance matches the amplifier’s output impedance.

So to recap, resistance is simply restriction to current flow in the circuit. For example if you touch any "hot" wire in your car to ground (zero resistance between + and -), the fuse upstream of that hot wire will blow because there's no restriction of current flow through the circuit and the fuse simply cannot handle the excessive current flow. Likewise if you hook up a lower-than-specified resistance speaker to your amplifier, it will allow higher-than-specified current to flow, as such, you can do one of 2 things: 1) Wire the speaker directly to the amplifier and feed the speaker with current it's designed to handle, which will risk overheating and damaging the amplifier, or, 2) Introduce additional resistance to the circuit to limit current flow to protect the amplifier and starve the speaker. In either case, you're limited to the lowest common denominator.

All that being said, you should be OK if you don't run your ML consistently at over 50% volume. Most solid state amplifiers are typically equipped with an overheat protection circuit that will shut itself down before any real damage is done - I'm not sure if the ML has such protection. Can anyone confirm?

2KHarrier

Thanks for the assistance Brother

2KHarrier

Well, I installed the Polk DB40DVC Sub yesterday. It went pretty straight forward, as far as installations go. I have to say, I'm not overly impressed with the low end response of the Polk VS. the original ML. I will be ordering the re-foam kit for the sub and reinstalling it later this month. I guess there is no substitute for OEM...