Audio Sound

Lecati · January 20, 2003

Hi everyone,

Currently I am test driving a GS300 Executive 2002, to replace my Is200. My question is. Does anybody sympathize with me that the radio just sounds awful for such a good car?! The CD is great. I can't find it but it seems that this one is equipped with a Mark levinson system.

What can one do to enhance the radio? Because hearing the CD indicates that the speakers are great. (I would says nearly as great as an IS series!)

The car I have in mind is not equipped with the Levinson system I believe, does that make much difference in quality?

I hope this improves because I don't like it much if the radio is not Ok, on the other hand it drives great.

regards

Lecati

L3X JG · January 20, 2003

Oh yes a big diff without marks presents. There is not much you can do abount the radio although i dont think it as bad as you might think maybe you were just in a bad area? does the one you are looking at have sat nav

Rodders_UK · January 21, 2003

Apparently this was a deliberate move by Lexus to attenuate the radio channel to "European ears" (go figure).

You can remove the attenuation and make the radio sound the same as the CD, but it involves removing a surface-mount capacitor in the amp, which is pretty tricky without the right equipment and a fair degree of knowledge.

I can prolly lay my hands on the instructions if you want to give it a try.

L3X JG · January 21, 2003

Well done Rodders if you can get me the destructions i will do it and post some pic to help others :hocus-pokus:

Dobbin · January 22, 2003

I've got the original instructions from justin Crockett for the mods that needed to be done to the Mk 1 radio. Its the same as Rodders is describing - I'll email the pictures to you but here are Justin's comments about the mod:-

Firstly, do you have experience of surface-mount technology? If not I suggest you don't touch the radio.

Secondly, do you know how to remove the radio from the dash? Again if you are not sure seek professional advice.

Now that that's over I've attached two drawings from the Pioneer manual.

The two capacitors to remove are C101 and C102 on the Tuner PC board. both are of 0.056mfd and are chip capacitors that shunt the junctions of R101/102 and Q101 and Q102 to earth.

They are fairly easy to locate, just follow pins 25 and 26 from connector U21 (in the middle of the board layout) through R101 and R102 and the two capacitors shunt signal to ground on the base of Q101 and Q102.

This is a totally unofficial modification, you carry it out at your risk.

Roughly the time constant of 2.2K ohms and .056mfd is: 123 microseconds, the correct UK FM de-emphasis time constant should be 50 microseconds, however this is already accomplished by C151/R151 and C152/R152 on the Tuner PCB (3.3K and .018mfd = 59 microseconds minus a bit for source impedance is probably 50 microseconds)

I reckon they mis-specified C101/102 they should be more like 560pf