Mark Levison

[Radiance]

i have a problem with my Mark Levison System in my 2006 IS350....been to the dealears three times now but the problem still exists...... does anyone know if there are Mark Levison Specialists that can diagnose the problem. please advice.

the problem:

there is "intermitten" crackling sound in the left rear door speaker and all the sound seems to come from the front speakers and nothing from the rear.

service department reset the tre, mid, and bass levels and said the spearkers are fine since the service tech did not hear the crackling sound when the car was brought in.......they advice that i should leave all the settings untouched from factory setting because the ML processor will produce the best sound autmatically.....(which does not make sense to me)...is that true?

service tech also advice that the speakers in the rear are only for "fill" sound and they should be much softer in their output comparing to front speakers (which also does not make sense to me)...is that true?

finally service department identified the cracking sound was due to a blown rear door spearker and replaced it. i asked the service tech does that mean all this time i have no output from the blown speaker and why the crackling sound is only intermitten......service tech response was only certain sound frequencies were lost in the blown speaker and only when those frequencies are played will have the crackling sound and output is fine with other sound frequencies (which does not make sense to me, i think a blown spearker should have not output at all)....is that true?

with a new rear speaker, there is still cracking noise......and now i noticed that the middle spearkers on both rear doors have no sound output.

i am not confident that the service department can properly solve the prolbem, i would prefer to have a specialist that is familiar with the Mark Levison System to diganose the system once and for all so that i can have it fixed.

Please advice.

thank you very much.

[dcfish]

i have a problem with my Mark Levison System in my 2006 IS350....been to the dealears three times now but the problem still exists...... does anyone know if there are Mark Levison Specialists that can diagnose the problem. please advice.

the problem:

there is "intermitten" crackling sound in the left rear door speaker and all the sound seems to come from the front speakers and nothing from the rear.

service department reset the tre, mid, and bass levels and said the spearkers are fine since the service tech did not hear the crackling sound when the car was brought in.......they advice that i should leave all the settings untouched from factory setting because the ML processor will produce the best sound autmatically.....(which does not make sense to me)...is that true?

service tech also advice that the speakers in the rear are only for "fill" sound and they should be much softer in their output comparing to front speakers (which also does not make sense to me)...is that true?

finally service department identified the cracking sound was due to a blown rear door spearker and replaced it. i asked the service tech does that mean all this time i have no output from the blown speaker and why the crackling sound is only intermitten......service tech response was only certain sound frequencies were lost in the blown speaker and only when those frequencies are played will have the crackling sound and output is fine with other sound frequencies (which does not make sense to me, i think a blown spearker should have not output at all)....is that true?

with a new rear speaker, there is still cracking noise......and now i noticed that the middle spearkers on both rear doors have no sound output.

i am not confident that the service department can properly solve the prolbem, i would prefer to have a specialist that is familiar with the Mark Levison System to diganose the system once and for all so that i can have it fixed.

Please advice.

thank you very much.

Have the service dept. replace the headunit/amp. I take it this is warranty work...Correct ? Blown speakers can still have a degree of output.

[smooth1]

i have a problem with my Mark Levison System in my 2006 IS350....been to the dealears three times now but the problem still exists...... does anyone know if there are Mark Levison Specialists that can diagnose the problem. please advice.

the problem:

there is "intermitten" crackling sound in the left rear door speaker and all the sound seems to come from the front speakers and nothing from the rear.

service department reset the tre, mid, and bass levels and said the spearkers are fine since the service tech did not hear the crackling sound when the car was brought in.......they advice that i should leave all the settings untouched from factory setting because the ML processor will produce the best sound autmatically.....(which does not make sense to me)...is that true?

service tech also advice that the speakers in the rear are only for "fill" sound and they should be much softer in their output comparing to front speakers (which also does not make sense to me)...is that true?

finally service department identified the cracking sound was due to a blown rear door spearker and replaced it. i asked the service tech does that mean all this time i have no output from the blown speaker and why the crackling sound is only intermitten......service tech response was only certain sound frequencies were lost in the blown speaker and only when those frequencies are played will have the crackling sound and output is fine with other sound frequencies (which does not make sense to me, i think a blown spearker should have not output at all)....is that true?

with a new rear speaker, there is still cracking noise......and now i noticed that the middle spearkers on both rear doors have no sound output.

i am not confident that the service department can properly solve the prolbem, i would prefer to have a specialist that is familiar with the Mark Levison System to diganose the system once and for all so that i can have it fixed.

Please advice.

thank you very much.

Have the service dept. replace the headunit/amp. I take it this is warranty work...Correct ? Blown speakers can still have a degree of output.

Okay, first of all, I would ask the dealership which one of their certified mechanicsis also a digital electronics specialist. I doubt very much that they have one.

Before I can maybe diagnosethe problem, without the unit in front of me I have to ask you some questions.

1) Does the crackling sound increase with the volume? Either in frequency and in volume.

2) Does the crackling happen while adjusting the volume or after wards?

3) Does it seem to stress the crackiling noise if you increase the bass level, or treble level, or no change at all?

4) Which speakers exactly make the crackling noise? Does the noise go away when you use the fader to isolate the front speakers?

5) Which speakers have no output? If you again use the fader, balance controls, can you isolate those speakers and determine if it is a seriously deficient output or no output at all?

By the way, you don't need a Mark Levinson specialist. They use electronic componentry just like every one else. Although at one time, Mark Levinson was the best that money could buy. I have a No. 33 CD player and a 15 CD transport. 12 years ago it cost $35000.00 for that set up. trust me, they are not using that technology in your car.

BTW, the warrentee is a good point. Even if I diagnosethe problem, they are not going to open the unit and replace an oscilator or anything. they will end up replacing the whole unit anyway. ( Because they of course don't have an electronics specialist.) And one other thing, tell the tech who told you about the frequency thing and the speakers to back to working on his little red wagon! What an idiot. I think he was just blowing smoke at you because they have no clue.

The Mark Levinson system uses a digital sound processor to digitally focus the sound in the car. It is true that there are some speakers used for "ambient " purposes, but that will depend on the adjustments to the sound prefrence by the user. Are you using preset modes or custom sound tuning the system yourself?

What state do you live in BTW? I might have aplace for you to be able to take it in and find out for sure.

to be honest, I don't think you have a speaker problem. I'm at this point not even sure you have an electronics problem. So, please answer the questions at the top and I'l be able to atleast get you pointed in the right direction.

[Radiance]

Hello "Smooth1".

thanks for your expert advice.....

here are the answers to your questions:

1) Does the crackling sound increase with the volume? Either in frequency and in volume

Answer: Yes, both in frequency and in volume...however, it is intermittent....i can be playing the same songs....sometimes it has the crackling sometimes it doesn't.

2) Does the crackling happen while adjusting the volume or after wards?

Answer: crackling happens during the adjustment.....crackling will be louder and more audible at higher volume setting....around 25 to 30....and very loud at 35.

3) Does it seem to stress the crackiling noise if you increase the bass level, or treble level, or no change at all?

Answer: Very minor differnce....but i would say a little more with the bass level

4) Which speakers exactly make the crackling noise? Does the noise go away when you use the fader to isolate the front speakers?

Answer: the lowest speaker (near the foot) on the left rear door.

5) Which speakers have no output? If you again use the fader, balance controls, can you isolate those speakers and determine if it is a seriously deficient output or no output at all?

Answer: there are three speakers on each rear door - top one at the window, middle one near the door handle, and the lower one near the foot) and currently the middle speakers near the door handle on each rear door have no output.

I am in San Francisco, California.

too bad you are so far away, otherwise i would drive the car for you to see.

Anyway, much appreciate your advice.

thanks.

Jackie

[smooth1]

Okay, I think you have 1 of 3 possible problems here.

1) ( this is the one I think is right.) - You may have a bad cross-over. Mounted in the door is a cross-over network which seperates frequency ranges and sends them to the assigned driver. If you have a bad cross-over it may be causing a power draw which also explains the lack of output you are getting to those speakers. Could be short in the transformer, or bad wiring.

2) before we think this is the possible problem, I have to ask a few more q's.

A) does it matter if you listen to the tuner or CD player? Do you have any aux. input devices in use? does it do it with them also? So this could be a bad amp channel. there should be a seperate fuse built in the amp itself. I would have them check that fuse and also test the output of the amp itself, not the speaker's output. This may also explain if the first speaker was indeed blown, why it would be blown in the first place. Not just replacing the speaker!

3) It could be a deficient ground wire and you may be picking up interference. the DSP system may be recieving it and isolating it or maybe trying to process that as a signal. In the old days if you didn't use a line filter on the electrical system you would pick up buzz from the ignition system. While we now don't use a magneto any more, Lexus is noted for having a poorly grounded electrical system on their cars. I don't think this is really the issue here, but it is possible. It may explain the intermittance issue. But not the lack of output.

Hope this helps you out. Let me know what they come up with. You have my curiosity peeked here. I've never diagnosed a audio problem like this before over the internet. It would really have helped to hear the problem first hand. For all I know you may have some bad or loose screws on the door and you may be hearing a vibration coming from the door!!!

In any case, Good luck!

[MrL]

I disagree that this is likely to be a crossover problem. Most OEM premium car systems these days (including ML) use a separate amp channel for every speaker. The DSP acts as a digital EQ so crossovers aren't generally needed. There are some exceptions, but the crossovers rarely consist of more than a single capacitor in series with a tweeter.

This sounds to me like an electronics problem, either in the radio head unit or the amp itself. Have your dealer try both, I would start with the amp.

Intermittent noise in car electronics is usually caused by cracked solder joints which are pushed together or pulled apart depending on temperature. If warm weather or cold weather brings it on more, or if it only happens before or after the system is warmed up, this would suggest that as a prime suspect.

Severe but intermittent noise in speakers is usually the result of debris inside the speaker which can get there any number of ways. The chances of this happening in multiple speakers in your car is very slim and would still not explain the low output from other channels. "Blown" is not a term that has any real meaning at all. There are lots of things that can cause a speaker to sound hideous or not work at all. "Blown" is a catch-phrase for all of them when one cannot be more specific.

Good luck!