peteharvey

Here are some pages from my Lexus 3GS350 Manufacturer's 6 Volume Workshop Manual.
The simplist fix is to bypass the manufacturer's Mark Levinson amplifier under the boot lining, and install a much more powerful aftermarket amplifier.

Remember that loudness is proportional to the Wattage, to the power of three!
Thus, we must increase the Wattage 8 times, just to double the volume!
Hence, we want something many times greater than the OEM's 300 odd Watts.
900 Watts RMS would be good, considering that the 4GS has 835 Watts.

And don't worry about blowing up your speakers!
We will never crank the signal to its maximum.
The powerful amps work by not having to work hard, therefore less distortion.
The big amps work by working effortlessly to produce their power, hence no, or little distortion.
It's like comparing a lazy V8, versus a raucous in-line four working its guts out.

In the world of audio, the max output of the amp must be much higher than the max output of the speakers, so that the amp can work "effortlessly", at a fraction of its max capacity - free from distortion, to produce its power.
Of course, if you do really crank up the volume dial to generate a stronger millivoltage signal from the head unit, you will get more amplification from the amplifier in the boot, that can damage your speakers, but no one cranks the volume dial up to that level.

You could purchase a genuine 2012-19 4GS 835 Watt Mark Levinson amp from Lexus Sewell, but it would probably cost you an arm and a leg, and it will most probably not fit under your 3GS boot.
Best buy an aftermarket amplifier - many makes and models to choose from, but 900 Watts from a reputable manufacturer would be good.
Bolt the new aftermarket amp to the back of the rear seat back rest, in the boot.

You could change the speakers, but much more labor.
If you weren't satisfied with the amp upgrade, then the next step is to change all the speakers, but I'm sure most will be happy with a much more powerful aftermarket amplifier.
The Mark Levinson 300 Watt OEM amplifier under the boot lining is tiny.
Look at these photocopies from my Workshop Manual...








I do notice that you have a 2013 4GS with 835 Watts of power; it should sound wonderful.
Get it checked out.
Bring along your favorite 2-channel stereo CD and 5.1 channel surround DVD with music recorded in genuine Dolby Digital 5.1, and play it back to back, and side to side with another 2013 4GS at the dealership.
Compare your 4GS with the 4GS at the dealership.

If your 2013 4GS has no fault, and you still don't like the sound, then perhaps you are very picky/discerning, and you will need to actually change the speakers first.
The speakers are the weakness in the GS, because Mark Levinson does not really make speakers.
Mark Levinson does not specialize in speakers.
The GS will most probably use a generic brand of speakers.
And if not happy with the aftermarket speakers, then upgrade the 835 Watt 2013 4GS Mark Levinson amplifier.
The head unit of the GS with the digital radio, DVD player etc, normally puts out a very clean signal - just as well, because it isn't really upgradeable, without a lot of aftermarket modifications...

modthispny

driving home from work, i took your advice and turned off surround, it took a few seconds for my ears to adjust, but the overall sound is much more balanced and sounds better. with surround on, when i would turn it up to around 45, i felt as if the highs/treble were too high, even though it was set to middle in the settings, but with surrounds off, it sounds perfect.

non-audiophiles might think it sounds better with the surround on, but anybody that has a ear for sound will definitely go with surround off.

thanks!!

sam430

iTrader: (10)

Anyone have specs on the speakers and locations? Not that I'm going to upgrade but specs is very important to those that wants to do it.

I have these class GH amps that looks like oem. 1000 watts/ 500watt rms I believe.



I wonder what the spec is for oem.

ShermanMR2

Thank you so very much for the write up. I wholeheartedly agree with you about everything you said. I would consider myself a little bit on the picky side however my wife who knows nothing about sound commented that something was very wrong. My neighbor who is a sound engineer indicated to me that there are some holes in certain frequency ranges. Who knows maybe there is something wrong with the system. I will be going to Lexus tomorrow and will definitely indicate that I have concerns about this. My only problem is, that they will just dismiss me due to lack of their expertise about the system.

mso4

iTrader: (1)

I'm happy with the ML. I agree that it is not boomy but the sound natural and in my opinion excellent. Very crisp and clear. Currently I have surround and leveling ON so will switch it to OFF to see if it gets better. Luckily mine does not rattle.

I listen to mainly BT, AUX, and FM. I do not listen to XM that stuff sounds horrible.

SKA430

So were you able to get it checked out / compare its performance to another 4GS with ML? I wasn't able to get the color combination I wanted with ML, and although I am overall happy with the non-ML because I have to like it, I could hear a major difference when I tested the two systems side by side with my own music that I brought with me. My last 2 3GS's had ML and this is the one item I am heart broken not to have on this awesome car.

ShermanMR2

The dealer called me today and told me that all was fine with the system (surprise). On Monday when I pick up my car I will do some side by side comparisons.

BigAnthony

I had a ML system in my 07 GS350 AWD and it sounded very good. There were no ML, F-sport with AWD available as yet. I have a 13' GS F-Sport AWD with no ML and it does not sound that good. I think I will start with an amplifier upgrade and see how it sounds and go from there. Anyone upgrade the sound system in a new GS yet?

ShermanMR2

To continue the saga, I picked up my car from the dealer and to my surprise they didn't find any problems with the system. I did some A B testing with Daniel who is an audio guy that works at the dealer. It turns out that the system is CRAP!!! I have proof of this... We both agreed that the system wasn't tuned properly to the car and there was one very large omission on this system. Directional tweeters on the doors!!! How could they miss that?!? Well I guess it's off to the car stereo shop to see if I could fix Mr. Levenson's mistakes.

e39ng

Here's the specs of speakers for Standard and ML:

[URL="[ame=http://www.flickr.com/photos/34602213@N08/8429426682/][/ame]"]http://www.flickr.com/photos/34602213@N08/8429426682/[/ame]
[URL="[ame=http://www.flickr.com/photos/34602213@N08/8428336257/][/ame]"]http://www.flickr.com/photos/34602213@N08/8428336257/[/ame]

ShermanMR2

Thanks for posting this. I will get the bottom of this and let you guys know what I ended up doing.

sam430

iTrader: (10)

Thanks E39NG! also note that the only major difference are a few speakers that cost about 4 times more and speaker number 6 does not exist on nonML (the two speakers in the rear deck beside the wooofer). I posted on another thread. You can upgrade those to ML spec from sewell or upgrade the speakers all-together.

Note: If you go back and compare parts you'll see only a few major speakers differences.

Next part would be a difference in amp. Now, does ML have something before the amp?????

ShermanMR2

Actually I think the first thing would be some sort of interface between the head unit and amp to change frequency parameters. Second would be to change speakers or add speakers.

sam430

iTrader: (10)

Something like an MS-8 or factory ML "processor"? U can stick a pair of ms8 between the head unit and amp. The ms8 only needs left and right for input. Then you can time align each ms8. You can then customise each frequencies. Choose any amp you want for each output from the ms8.

KILLERGS4

http://news.cnet.com/8301-13645_3-57...udio-vs-wires/