hello. I recently changed my car's 4 speakers and I measured the polarity of them while wiring and it turned out that rear speakers output is the opposite. I confirmed it by removing the head unit and measured it with a multimeter and both rear left and right + is - fronts are ok. did they do it on purpose or it is a factory fault? I'm planning to crosswire the extension cable. did you notice something like this?
Huh? How did you measure with a multimeter?
Did you play a low frequency tone and check the voltage between the FL+ and RL+ on the AC range?
Renate said:
Huh? How did you measure with a multimeter?
Did you play a low frequency tone and check the voltage between the FL+ and RL+ on the AC range?
Click to expand...
Click to collapse
I turned up the volume and checked the dc voltage between RL + RL - and RR+ RR- multimeter showed - signal. for fronts it didn't show - .
esmeraldo18 said:
I turned up the volume and checked the dc voltage between RL + RL - and RR+ RR- multimeter showed - signal. for fronts it didn't show - .
Click to expand...
Click to collapse
No, that's not really a test. There might always be a little residual DC (at least as measured by a DC multimeter on a complex signal).
There are a zillion ways to check stuff, some just the electrical out of the HU, some the acoustic polarity out of the speaker.
If you put a signal into your HU you can compare the phase of the input signal vs that of a microphone sequentially in front of each speaker.
A low frequency assymetric wave can allow you to visually see which way the speaker cone is moving.
So that I wouldn't be caught out, I just checked my computer setup.
Channel ID came first, making sure that left is left.
Then I put 440 Hz tone out the computer.
Instead of locking to the PC output, I used a precision test oscillator which was certainly close enough to stay locked for a minute.
I used a microphone and compared the phase of the two signals.
I switched the microphone from in front of the two speakers alternately.
I could see that they both had the same phase.
The top trace is the microphone, the bottom the reference.
Ok, back to reality. You can check for electrical phase out of the HU by adjusting the channels evenly and connecting a speaker temporarily between FL+ and RL+. You should hear practically nothing out of the speaker.
so if I connect a speaker between FL+ and RL+ and hear nothing, does this mean polarity is correct. because I always measure the same polarity with multimeter for rears and same for fronts. I was completely sure that something is weird.
I tested this because when I turn up the volume for fronts only it has deep bass and good sound but when I start to turn up rears at balanced stage I hear no bass and when I turn up rears completely with turning down fronts I hear also deep bass. when the volume is balanced rear and front speakers cancel each other, that's why I tried to measure them, because I thought I connected speakers wrong but they were right so I removed the head unit and measured it also.
I used this video as a guide;
esmeraldo18 said:
I tested this because when I turn up the volume for fronts only it has deep bass and good sound but when I start to turn up rears at balanced stage I hear no bass and when I turn up rears completely with turning down fronts I hear also deep bass. when the volume is balanced rear and front speakers cancel each other...
Click to expand...
Click to collapse
Well, it does sound like a phase problem.
If it is, then switching things anywhere will fix it.
But if you want to treat this as a research problem you can look into exactly where this problem is.
Are the front and read speakers the exact same model?
It could be the HU, the wiring, the speakers.
esmeraldo18 said:
I used this video as a guide;
Click to expand...
Click to collapse
Yow! That's just wrong!
You cannot tune in your radio station and measure DC on speaker cables!
It's like a blind man measuring the size of an elephant by touching somewhere.
Your multimeter is taking a signal that changes thousands of times a second and trying to represent it with a number!
Yes, what he did with the little battery and the speaker is fine.
If you have a spare little speaker, hook it up between the FL+ and the RL+ with the F/R balance at zero.
It should get loud at all front or all rear and be quiet in the middle.
You can also check FR+ and RR+.
Then FL+ and FR+ (using normal L/R balance).
This just tells you that the HU is correct.
Renate said:
Your multimeter is taking a signal that changes thousands of times a second and trying to represent it with a number.
Click to expand...
Click to collapse
I got you. All I'm saying is I'm not trying to read some values or catch something with multimeter, it does not show a static number though. But it always shows same polarity no matter what radio plays. Isn't it something worth relying? And I'm pretty sure that hu is faulty because I'm measuring directly over the pins inside sockets and at the top there is a diagram that shows which pin is positive and multimeter gives negative results for rears. Fronts are ok. These units are mass production so I'm afraid many users have phase problems they don't aware yet.
Renate said:
If you have a spare little speaker, hook it up between the FL+ and the RL+ with the F/R balance at zero.
It should get loud at all front or all rear and be quiet in the middle.
Click to expand...
Click to collapse
I tested this, speaker was very quite when balanced at zero and loud all front or all rear. So what does it mean? Both cable is + and it shouldn't play anything right? But it plays when I change the balance?
esmeraldo18 said:
But it always shows same polarity no matter what radio plays.
Click to expand...
Click to collapse
It's showing nothing.
Moreover, since this is switch mode (class D) amplifier the signal is actually switching at 200-400 kHz.
esmeraldo18 said:
I tested this, speaker was very quite when balanced at zero and loud all front or all rear. So does it mean the unit is ok?
Click to expand...
Click to collapse
This means that the phase out of the HU is correct.
It's what I'd expect. It's pretty easy to get the design correct once.
Then they can make a million units and the phase will always be correct.
As I asked, are the rear speakers and the front speakers the exact same model, wired the same?
You can shrug your shoulders if you like and just switch the wiring so that the base is reinforced.
Renate said:
It's showing nothing.
Moreover, since this is switch mode (class D) amplifier the signal is actually switching at 200-400 kHz.
This means that the phase out of the HU is correct.
It's what I'd expect. It's pretty easy to get the design correct once.
Then they can make a million units and the phase will always be correct.
As I asked, are the rear speakers and the front speakers the exact same model, wired the same?
You can shrug your shoulders if you like and just switch the wiring so that the base is reinforced.
Click to expand...
Click to collapse
No, front and rear are different, because the diameter is different but I double checked the polarity before changing them and I'm pretty sure they were ok.
Update: Renate you were right, changing polarity made things worse, I believe lack of bass is related to another problem, probably different type of speakers causing this. Fronts are 16cm jbl stage 3 627f and rears 13cm sony xs-fb131e. I understand that using multimeter is wrong, thank you.
Related
When a sound in a certain frequency appears on my phone it comes with an annoying hissing sound especially on the left channel. it drives be bananas! i already sent it back and got a replacement and the bug is still there. Work arounds that didn't work for me: switching to ATR, Another audio cable, Sound About(my headphones is also detected as actual headphones), making a call.
I'm desperate for a solution. I hope it gets fixed with lollipop but if not i rely on you guys.
I already posted this on reddit and i keep you guys updated if i get a valuable answer.
i would really appreciate it if you got anything to help me out with.
retsam00 said:
When a sound in a certain frequency appears on my phone it comes with an annoying hissing sound especially on the left channel. it drives be bananas! i already sent it back and got a replacement and the bug is still there. Work arounds that didn't work for me: switching to ATR, Another audio cable, Sound About(my headphones is also detected as actual headphones), making a call.
I'm desperate for a solution. I hope it gets fixed with lollipop but if not i rely on you guys.
I already posted this on reddit and i keep you guys updated if i get a valuable answer.
i would really appreciate it if you got anything to help me out with.
Click to expand...
Click to collapse
Does it appear when using the headphones that came with the G3? And which headphones are you using?
in response
Xerionius said:
Does it appear when using the headphones that came with the G3? And which headphones are you using?
Click to expand...
Click to collapse
i'm using the ath m50x from audio technica. ****ty in ear headphones including the lg earbuds doesn't have this problem since they're not very sensitive.
thanks for your help mate
by the way it works perfectly fine on the s5 and my computer
retsam00 said:
i'm using the ath m50x from audio technica. ****ty in ear headphones including the lg earbuds doesn't have this problem since they're not very sensitive.
thanks for your help mate
by the way it works perfectly fine on the s5 and my computer
Click to expand...
Click to collapse
It's not about sensitivity, it's about impedance. Headphones with a low impedance always have this problem on the G3.
Unfortunately there is nothing you can do, except for using other headphones or soldering a resistor in row to your headphones, but that would ruin the HiFi-capabilities of the M50X.
In my experience, Headphones with 20+ Ohms work well, but it seems that the M50X (which have 38 Ohms) don't have a very linear impedance.
I've talked to LG about that issue, but their support doesn't know anything about anything. After a long discussion about it not being a defect, she just said that she will forward the complain to their engineers...
You're not the only one though
damn this is too bad. i hope it can be fixed with a software update unfortunately i can say that the support indeed is pretty bad at least from my point of view they doesn't seem to have any IT experience.
retsam00 said:
damn this is too bad. i hope it can be fixed with a software update unfortunately i can say that the support indeed is pretty bad at least from my point of view they doesn't seem to have any IT experience.
Click to expand...
Click to collapse
It can't be fixed via software. It's a hardware issue.
I think a headphone amplifier unit should 'correct' the issue assuming my understanding of wikipedia is incorrect
Output Impedance
Many headphone amplifiers have an output impedance in the range of 0.5 - 50 Ohms. The 1996 IEC 61938 standard recommended an output impedance of 120 Ohms, but in practice this is rarely used and not recommended with modern headphones. High output impedance can result in frequency response fluctuations, due to varying load impedance at different frequencies. In 2008 Stereophile Magazine published an article that showed that a 120-Ohm output impedance could cause a 5-dB error in frequency response with certain types of headphones. However, the author of the article also states: ″The ramifications for subjective assessment of headphones are more troublesome because it is usually unclear what assumptions the manufacturer has made regarding source impedance. ″ [2]
More importantly, low output impedance can reduce distortion by improving the control that the source has over the transducer. This is often expressed as damping factor, with higher damping factors greatly reducing distortion.[3] One company shows a 45 dB improvement in THD+N at 30 Hz for their low-impedance amplifier compared to a 30-ohm amplifier.[4] For example, a 32 Ω headphone driven by a headphone amp with a <1 Ω output impedance would have a damping factor of >32, whereas the same headphone driven with an iPod Touch 3G (7 Ω output impedance) [5] would have a damping factor of just 4.6. If the 120 ohms recommendation is applied, the damping factor would be an unacceptably low 0.26 and consequently distortion would be significantly higher. Conversely, the same iPod Touch driving a pair of 120 ohm headphones would have a respectable damping factor of 17.1, and would most likely not benefit from the addition of a lower impedance headphone amplifier.
In addition to output impedance, other specifications are relevant to choosing a headphone amplifier — THD, frequency response, IMD, output power, minimum load impedance, and other measurements are also significant. However, most of these will be improved by lowering output impedance and hence improving damping factor.
Click to expand...
Click to collapse
dryjoint said:
I think a headphone amplifier unit should 'correct' the issue assuming my understanding of wikipedia is incorrect
Click to expand...
Click to collapse
That's right, a dedicated headphone amplifier would fix this, because the input impedance is typically very high.
But most heaphone amps in the lower price range decrease sound quality significantly.
The problem I'm facing..
There is noise+distortion+hissing during call but ignore-able
And when headphones are connected I cant understand or listen to any thing I only hear wired noises..
Any fix guys ?
Dont know if its technical or software based issue
if technical then I bet it could be faulty ic chips
omr911 said:
The problem I'm facing..
There is noise+distortion+hissing during call but ignore-able
And when headphones are connected I cant understand or listen to any thing I only hear wired noises..
Any fix guys ?
Dont know if its technical or software based issue
if technical then I bet it could be faulty ic chips
Click to expand...
Click to collapse
To me that sounds like a hardware issue. I'd contact LG.
Xerionius said:
To me that sounds like a hardware issue. I'd contact LG.
Click to expand...
Click to collapse
I sent my G3 to service center and today they gave me a new replacement phone, that one had indeed technical problem and the main board replacement wasn't available :highfive:
I have a MTCD GS unit for an Audi TT and I get a feint electrical noise constantly through the cars speakers. If you have music or the radio on it is not too noticable but otherwise it is really obvious. It is definitely the unit as it isn't there with the stock head unit and if you hard reset the GS unit with the reset button whilst it is running it immediately goes away until the unit has booted. It was originally supplied with a RK3188/PX3 board running Android 5.0. I have since replaced the board with a PX5 board and have upgraded it to Android 8.0 (Malaysk). I isn't a software issue and is down to the hardware (I think...).
I have tried disabling WiFi and BlueTooth - although I don't think BlueTooth can be disabled as its not a native Android component of the system - and the noise remains. It is a feint pop and hiss noise that I think is an earth/grounding issue. I was going to replace the cable that goes to the WiFi antenna on the rear socket as this looks flimsy, however I am not sure it will make a difference.
Any ideas?
Andy
dirty power maybe? did you connect a chassis ground for the 0v on the unit.. my harness came with a ground with ring terminal..
Sent from my PH-1 using Tapatalk
I have exactly same problem. But when the colors on LCD screen black : electrical noise increases. Any other color : electrical noise decreases. I will check groundings of unit in this weekend. I ll write here if i find out anything.
stinger4321 said:
dirty power maybe? did you connect a chassis ground for the 0v on the unit.. my harness came with a ground with ring terminal..
Sent from my PH-1 using Tapatalk
Click to expand...
Click to collapse
It shouldn't be dirty power as it connects into the factory loom. I'll take it out at weekend and see if grounding the chassis of the head unit to the car does anything.
Andy
I had this problem on my ksp. Ultimately I found opamps under the sound processor with dirty ground on the feedback resistors. I substituted resistors to the processor board ground header lead. Now all I hear is my fan.
I took the head unit out last weekend and tried earthing the chassis to the car and it made no difference - you can still hear the feint pops and hiss (all I can think to describe it is radio interference?). I also noticed that it gets worse when the cars lights are on and the head unit backlights come on (via CANBUS telling it I assume?).
It is a MTCD GS unit and has an external 'dongle' that is covered with heatshrink that is inline with the audio outputs. This has something to do with the level of the audio out - however I am just guessing here TBH.
Any other ideas how to eliminate this noise?
Cheers
Andy
ADB100 said:
I took the head unit out last weekend and tried earthing the chassis to the car and it made no difference - you can still hear the feint pops and hiss (all I can think to describe it is radio interference?). I also noticed that it gets worse when the cars lights are on and the head unit backlights come on (via CANBUS telling it I assume?).
It is a MTCD GS unit and has an external 'dongle' that is covered with heatshrink that is inline with the audio outputs. This has something to do with the level of the audio out - however I am just guessing here TBH.
Any other ideas how to eliminate this noise?
Cheers
Andy
Click to expand...
Click to collapse
Try grounding the PX5 board heatsink with the unit chassis.
iRcKenny said:
Try grounding the PX5 board heatsink with the unit chassis.
Click to expand...
Click to collapse
I had the same noise issue when the PX3 board was installed and this has a much smaller heatsink than the PX5?
I'll give it a shot but its a bit more involved than just taking the unit out of the car though...
Andy
ADB100 said:
I had the same noise issue when the PX3 board was installed and this has a much smaller heatsink than the PX5?
I'll give it a shot but its a bit more involved than just taking the unit out of the car though...
Andy
Click to expand...
Click to collapse
So, you also have that noise before upgrading the core board, have you any chance to temporaly install another common radio like low budget Pionner, Alpine or similar? If yes check if the noise persist; some TT owners with noise from speakers said that the cause is the factory amplifier.
Have luck!
i have heard that the problem may be from the antenna, try getting a noise filter for the antenna
Record the noise with a video. Some quiet electrical noise is common, but we're talking almost silent and only when no music is playing at all.
ADB100 said:
I took the head unit out last weekend and tried earthing the chassis to the car and it made no difference - you can still hear the feint pops and hiss (all I can think to describe it is radio interference?). I also noticed that it gets worse when the cars lights are on and the head unit backlights come on (via CANBUS telling it I assume?).
It is a MTCD GS unit and has an external 'dongle' that is covered with heatshrink that is inline with the audio outputs. This has something to do with the level of the audio out - however I am just guessing here TBH.
Any other ideas how to eliminate this noise?
Cheers
Andy
Click to expand...
Click to collapse
I have the same thing on my A3 and although it doesn’t really bother me I’d be interested to see if someone finds a fix. On the A3’s it only affects the ones with Bose.
All my cabling is exactly the same as yours aswell.
I once emailed a company that sells the factory Bose amps for the audis and reconditions them and the bloke said that the signal sent to the Bose amp from the aftermarket headunit is different to the signal that is sent from the factory unit so I’d guess it’s something to do with that.
In regards to the dongle thing in heatshrink, that is a little board with a plug on it that the audio cables plug into. My speakers stopped working so I cut that open once and the connector had become unplugged inside. I think it’s there because the blue amp cable is connected through it aswell which is supposed to be for the amp to turn it on and that blue cable never used to be there on the older model units.
I have the same issue on my brand new dasaita 10.2 inch px5 android 8. Connected through RCA to my amp.
I will do some troubleshooting and see if I can figure it out.
BTW, there is a very loud static noise when my bluetooth is connected to my phone, I emailed dasaita about that particular issue.
checksum123 said:
I have the same issue on my brand new dasaita 10.2 inch px5 android 8. Connected through RCA to my amp.
I will do some troubleshooting and see if I can figure it out.
BTW, there is a very loud static noise when my bluetooth is connected to my phone, I emailed dasaita about that particular issue.
Click to expand...
Click to collapse
I have the same unit with the same issues. Hot Audio sent me a replacement bluetooth module to solder in. That fixed the bluetooth noise. I still have slight background hiss all the time.
could you guys please take a look at my issue which includes electrical noise - even when radio is off.
e.g.
- downloading maps on Sygic, there is a clicking that goes with the increase in % of the download.
- browsing the menu and / or selecting apps has a varying noise
Interestingly, the rear-camera power seems unstable as does the GPS.
I also noted, that i couldn't power the unit on the bench via the vw quadlock connector, i had to use the white connector.
Makes me wonder if there is some general grounding problem that is the problem.
https://forum.xda-developers.com/an...droid-8-px5-mtcelmv2-881-vw-multiple-t3884665
I have an equal problem with my eonon px3 7.1, which is then klyde. Light rustling always constant, then when I register with the front usb camera the noise is much higher and seems a squeak of mouse .. I changed mb sent by them but the problem remains, even connecting the ground to the chassis of the car. Quache solution please guys, I'm going crazy.
gwaitsi said:
could you guys please take a look at my issue which includes electrical noise - even when radio is off.
e.g.
- downloading maps on Sygic, there is a clicking that goes with the increase in % of the download.
- browsing the menu and / or selecting apps has a varying noise
Interestingly, the rear-camera power seems unstable as does the GPS.
I also noted, that i couldn't power the unit on the bench via the vw quadlock connector, i had to use the white connector.
Makes me wonder if there is some general grounding problem that is the problem.
https://forum.xda-developers.com/an...droid-8-px5-mtcelmv2-881-vw-multiple-t3884665
Click to expand...
Click to collapse
ADB100 said:
I have a MTCD GS unit for an Audi TT and I get a feint electrical noise constantly through the cars speakers. If you have music or the radio on it is not too noticable but otherwise it is really obvious. It is definitely the unit as it isn't there with the stock head unit and if you hard reset the GS unit with the reset button whilst it is running it immediately goes away until the unit has booted. It was originally supplied with a RK3188/PX3 board running Android 5.0. I have since replaced the board with a PX5 board and have upgraded it to Android 8.0 (Malaysk). I isn't a software issue and is down to the hardware (I think...).
I have tried disabling WiFi and BlueTooth - although I don't think BlueTooth can be disabled as its not a native Android component of the system - and the noise remains. It is a feint pop and hiss noise that I think is an earth/grounding issue. I was going to replace the cable that goes to the WiFi antenna on the rear socket as this looks flimsy, however I am not sure it will make a difference.
Any ideas?
Andy
Click to expand...
Click to collapse
I have the same isue, almost gone when changed the poor quality antenna from the WIFI (used a 9DB antenna)
Pick one from amazon,
https://www.amazon.com/gp/product/B07GDCLVPJ/ref=ppx_yo_dt_b_detailpage_o00_s01?ie=UTF8&psc=1
You can try to purchase a extension canble an antenna and put away from the unit and the engine.
In my case the pops and hiss almos gone and are barely noticiable.
The qualty of the original antenna is horrible.
jerrymh said:
I have the same isue, almost gone when changed the poor quality antenna from the WIFI (used a 9DB antenna)
Pick one from amazon,
https://www.amazon.com/gp/product/B07GDCLVPJ/ref=ppx_yo_dt_b_detailpage_o00_s01?ie=UTF8&psc=1
You can try to purchase a extension canble an antenna and put away from the unit and the engine.
In my case the pops and hiss almos gone and are barely noticiable.
The qualty of the original antenna is horrible.
Click to expand...
Click to collapse
by that token, simply turning off the wifi would prove it no?
gwaitsi said:
by that token, simply turning off the wifi would prove it no?
Click to expand...
Click to collapse
You would think so wouldn't you?
I have a couple of spare SMA WiFi antennas that I can try. If I get some time later today I'll try and get the head unit out of the dash and try them. I'll post whether it makes any difference (the spare antenna I have might also be crap though...).
Andy
What I found helped is that I put some ferrite beads on the power cables to the headunit and the speaker cables from the unit. It hasn’t totally removed the issue but it is certainly better and I haven’t lost any sound quality(if anything it’s slightly better as there’s less interference).
Hello,
I have an other problem, i have noise in the speakers like when i accelerate, the sound of the engine speed appears on the speakers !
All is ok between the HU, just i have 5/6 RCA that is not connected... Is it possible that is this RCA the problem ? What can i do please ?
Someone can tell me what can i do ?
Thank you !!
If it’s like a wining noise that changes with the revs, that’s usually caused by poor earth connection.
Sent from my iPhone using Tapatalk
Earthing issue, alternator whine, or just bad insulation on your speaker wires. Look at some isolators and noise filters.
it may be an issue with the am/fm antenna, try disconnecting and see if you have speaker wine then. If theres no speaker wine when the antenna is disconnected, get an antenna noise filter
skezza said:
Earthing issue, alternator whine, or just bad insulation on your speaker wires. Look at some isolators and noise filters.
Click to expand...
Click to collapse
Getting isolators, noise filters or suppressors is just papering over the cracks so to speak. They do get rid of the noise but they also reduce your sound quality. It’s better to find the problem and fix it rather than just buying noise filters etc.
Id tape up all the connections behind the unit, check all the ground connections, or if your car has a factory amp it could be that the amp isn’t getting any power so this is one of the side effects that you see. I have an Audi A3 with Bose amp and this is one of the problems you get with these units if there is no blue amp cable supplied with the speaker cables to be able to turn the amp on.
ab1702 said:
Getting isolators, noise filters or suppressors is just papering over the cracks so to speak. They do get rid of the noise but they also reduce your sound quality. It’s better to find the problem and fix it rather than just buying noise filters etc.
Id tape up all the connections behind the unit, check all the ground connections, or if your car has a factory amp it could be that the amp isn’t getting any power so this is one of the side effects that you see. I have an Audi A3 with Bose amp and this is one of the problems you get with these units if there is no blue amp cable supplied with the speaker cables to be able to turn the amp on.
Click to expand...
Click to collapse
I agree. Papering over the cracks is a perfect description. Another decent saying is needle in a haystack.
Come back in 12 months when you still haven't got rid of it. These things can be a nightmare to solve.
I installed this unit in wife's 2018 Highlander today. It sounds great if wifi is switched off, or if it's on and no data is flowing. I am using Network Mini to monitor data, and as soon as data is going up/down, the crackling starts.
I've reached out to Dasaita and am awaiting a reply
I have grounded the black wire with the ringlet directly to the frame but it makes no difference. I have NOT grounded the radio chassis yet. Also the noise goes away when the unit isn't crammed into the dash. When all the wires are in close proximity to radio is when it picks up
Anyone seen this issue. Love the radio otherwise...
Video:.
https://youtu.be/NhSzLh7CD_0
Wow - that's REALLY bad... I'm starting to get a little fed up with the interference noises from my Eonon MTCE-WWW unit as well. I don't have any issues when using the internal amp, but if I connect to an external amp with the line-out RCAs, I get interference from USB devices, the LED backlighting on the unit, etc. It's shame becuase I love the idea of an Android unit, but not sure I can deal with the subpar quality issues....
Going to try connecting to my amp via speaker-level outputs next and see if that helps at all.
Do you have a stock or aftermarket amp in your vehicle?
Cracks and noises for me as well with my Belsee BP3 PX5 unit.
For me too the noises seem to fade away when I turn off WiFi.
I upgraded the firmware of the unit with a Cs-x sound mod one (there's an recente one for Dasaita too) and it seem to have reduced the issue
https://forum.xda-developers.com/an...ent/mod-cs-x-mod-mtcd-e-mcu-firmware-t3816042
Maybe you can check this out ?
TheDiB said:
Cracks and noises for me as well with my Belsee BP3 PX5 unit.
For me too the noises seem to fade away when I turn off WiFi.
I upgraded the firmware of the unit with a Cs-x sound mod one (there's an recente one for Dasaita too) and it seem to have reduced the issue
https://forum.xda-developers.com/an...ent/mod-cs-x-mod-mtcd-e-mcu-firmware-t3816042
Maybe you can check this out ?
Click to expand...
Click to collapse
I suppose I could try updates, but I don't hold out much hope given that the problem seems to be related to proximity to the wifi antenna. It did this on the stock rom, as well as the Hal9k variant.
I'll update this thread if I manage to find an improvement.
The alternate sound-patched MCU's didn't make any difference whatsoever on my Eonon MTCE-WWW unit. I tried both the cs-x version and the wazdio verion. Same noise-related issues. You may help "hide" them a little by turning down the pre-amp value, but you can also do that with the stock MCUs, under the Factory Settings "Voice" tab.
To put it simply, I think they just use low-quality components with limited R&D - which is why these units are so inexpensive compared to more premium brands of plug-and-play units like Rosen, Dynavin, etc (they run WinCE though).
If using speaker-level outputs on the Eonon doesn't help in my case, I'll probably be going back to a WInCE unit, just becuase they seem to have much higher-quality audio components (better DAC's, 4V pre-outs, BBE processor, real 9-band EQ, time-delay, etc). I was really looking forward to an Android head-unit, but I'm just not willing to sacrifice sound quality to get the Android interface. Viper4Android helps a LOT in terms of sound-quality, but it can't help with the noise-related issues, which are more of a hardware thing...
Maybe some day they'll get there. I really wish they made low- and high-end versions of these radios - that way people had a choice between low-cost and high-quality.
That's a shame, as there is so much potential. I have a Hizpo PK5 in my (JBL-equipped) Sequoia, and it's completely noise-free. But this Dasaita for the Highlander is just very loud. It seems like it's a shielding issue. As stated previously, if I keep the head unit out with all the cables extended, the sound stops. I'm halfway tempted to buy an SMA wifi antenna with a cable long enough to get the RF signal away from the wires. The sound is exclusive to the left channel (both front and rear).
@TheDiB, missed your prior question. It's a JBL-equipped vehicle.
Yeah, your particular noise is REALLY bad (mine is more of something that you only hear if the music is muted or during really quiet parts of the music - and only in certain cases (but it still bothers me knowing that it's there).
Being that you can stop the noise by pulling the radio out, you may be able to figure out what is causing it. Maybe try disconnecting the AM/FM antenna to see if that has anytihng to do with it - I've read some cases where hte antenna was causing interference. Or just re-routing some of the wiring - or something along those lines.
In my case, the noises are present no matter what - but only if I use the RCA line-level outputs and an extrnal amp. If I use the stock built-in amp, there is no noise whatsoever. So mine seems to be related to the RCA line-level output hardware (shielding related, I'm guessing).
I would experiment some more if you are happy with the radio and sound-quality otherwise.
I'm hoping I hear something helpful back from Dasaita in the coming days. On this particular unit, the wifi antenna comes out about 1/2" above the main ISO plug for the radio. I suppose I could relocate the antenna by running the existing bulkhead SMA fitting through a screw hole elsewhere on the case to provide more distance. I'm not giving up yet The other issue is that it's the wife's car, so my access to it is limited.
I'm not using line-level outputs. The four pairs for the speaker output comes out of that ISO plug, and goes straight to the Toyota harness. Fader control (as well as a bunch of other controls/data) goes through the can bus adapter. But ultimately, those four speaker pair end up at the factory JBL amplifier.
Aside from the noise, the audio quality is equivalent to the stock radio. But, I'm not an audiophile, and I have the opposite of OCD...
So your stock JBL amp actually accepts speaker-level inputs? Usually, amps take line-level inputs. With the Eonon MTCE-WWW units for GM's, if your car has a stock Bose amp, there is a special "Bose adpater" that connects to the same port where you would connect the line-level RCA jacks for aftermarket amps, which is line-level - but instead of having RCA jacks at the other end, it just connects into the main wiring harness, so I guess it sends line-level signals through the speaker wires, to the Bose amp - and then the Bose amp amplifies them (that is just a guess though, based on the fact that the audio is coming from the same port that is used for an external aftermarket amp, which is line-level).
So the wiring harness you use for yours is exactly the same regardless of whether the car has a stock amplifier or not? Or maybe it's not an option on your car and they ALL come with JBL amps? Just trying to understand your setup a little better. Do you have a link to the unit you purcahsed?
jtrosky said:
So your stock JBL amp actually accepts speaker-level inputs? Usually, amps take line-level inputs. With the Eonon MTCE-WWW units for GM's, if your car has a stock Bose amp, there is a special "Bose adpater" that connects to the same port where you would connect the line-level RCA jacks for aftermarket amps, which is line-level - but instead of having RCA jacks at the other end, it just connects into the main wiring harness, so I guess it sends line-level signals through the speaker wires, to the Bose amp - and then the Bose amp amplifies them (that is just a guess though, based on the fact that the audio is coming from the same port that is used for an external aftermarket amp, which is line-level).
So the wiring harness you use for yours is exactly the same regardless of whether the car has a stock amplifier or not? Or maybe it's not an option on your car and they ALL come with JBL amps? Just trying to understand your setup a little better. Do you have a link to the unit you purcahsed?
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It must, because I'm not using any coax/low-level outputs. In fact, I haven't hooked up most of the pigtail connectors. The ISO harness has about 5 or 6 connectors that are used, and about as many that aren't (presumably for the non-JBL vehicles). I think the Toyota JBL set up is much like the Bose you described. In a previous Tundra, I had to buy an adapter that would convert the two-pair per speaker wires to RCA plugs which I could then use to connect my aftermarket radio (to use the low level outputs). That converter (made by Metra or Scoche, IIRC) also somehow tied into the canbus to power the amp and control the fader.
Ultimately with this PX5, I'm using the purple/green/gray/white speaker level outputs to go directly to the factory harness. No adapter in between. I can only assume the JBL amp is designed to accept this somehow. Both my Sequoia and now this Highlander are set up the same way.
Well, I am happy to report that I was able to resolve the noise by replacing the Dasaita wifi antenna with a full-sized SMA-equipped antenna from an old Asus router. The antenna was a female SMA, so I had to slip a small copper conductor into it so it would interface with the female SMA bulkhead on the radio - but once I did that, ALL the noise disappeared! So either something is wrong with the antenna they provided, or it's simply dumping too much RF right on top of the ISO connector with all the speaker outputs. Whew!
Very cool! Glad to hear that you got it resolved. So is the antenna now further away from the ISO connector - or is it just becuase it's a different antenna? You may to get an adapter or an antenna with the right connecter for long-term use (instead of using the wrong gender anteanna with a piece of copper wire installed).
Regardless, glad to hear that you figure it out! I wish my noise-related issues were so easy to solve.
Although, I did some brief testing this morning and it seems that using the speaker-level outputs is better than using the line-level outputs on mine (for connecting external amp). The noises are still there, but they aren't as loud when using speaker-level outputs for my external amp (usually, it's the other way around with higher-quality head-units).
These units are so close to being really good - it's a shame they have these noise-relasted issues...
jtrosky said:
Very cool! Glad to hear that you got it resolved. So is the antenna now further away from the ISO connector - or is it just becuase it's a different antenna? You may to get an adapter or an antenna with the right connecter for long-term use (instead of using the wrong gender anteanna with a piece of copper wire installed).
Regardless, glad to hear that you figure it out! I wish my noise-related issues were so easy to solve.
Although, I did some brief testing this morning and it seems that using the speaker-level outputs is better than using the line-level outputs on mine (for connecting external amp). The noises are still there, but they aren't as loud when using speaker-level outputs for my external amp (usually, it's the other way around with higher-quality head-units).
These units are so close to being really good - it's a shame they have these noise-relasted issues...
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Click to collapse
I didn't move the bulkhead SMA fitting. I would have had to break the factory seal, and I didn't want to jeopardize warranty just yet. The antenna I added is about 4x longer than the stubby they provided, so I suppose it is spreading the RF over a larger area. It has a hinge on it and if I aim it straight back the noise is still present. Bending it 90° away from the harness makes it totally silent - and there is no depreciation in the signal strength.
I have ordered a gender changer and a 3" SMA extension cable from Amazon, but I probably won't install it unless the problem returns. I figure why rock the boat.
Is the noise you're experiencing related to data transmission? Does it stop if you disable the wifi? I'm wondering if wrapping the first few inches of the wiring bundle with copper tape wouldn't provide shielding against induced RF noise.
Ah - I see. Interesting - so just a different antenna resolved your issue. Like you said, I guess it's spreading out the signal enough to avoid causing the interference. I'm sure someone else will find that info very useful in the future!
My noise issues are not realted to wifi. I have interference noises in the following situations:
1. If car is not running and radio LED backlighting is on (cuases a hum through the speakers). Mainly only noticeable when no music is playing (between songs, for example) or when there are very quiet parts of the music.
2. When using my headrest monitors.
3. Anytime the system accesses USB devices. The interference is pretty noticeable when reading/writing USB thumb drives - especially if they have LEDs on them.
4. If I my Eonon USB dashcam is active, it makes a strange intference noise from the speakers. Again, really only noticeable when no music is playing, but...
None of these are huge issues in of themselves, but at the same time, it just bothers me knowing that the interference exists. I've also noticed that the overall sound quality just isn't as good as my previous WinCE-based head-units - (much more expensive units - they have 4v preouts, higher-quality DAC's, etc) - even when using an external amplifier. Never had interference noises with them, so the Android unit is really a downgrade in terms of sound-quality, which is more important to me than having Android, I guess. I was hoping that there woulnd't be much difference in sound quality when using an external amp, but there still is...
At first, I thought the Android head-unit was awesome while testng "on the bench" - until I connected it in-car and used it for a few days, then I started noticing all of the "cons" (warning chimes and turn-signal sounds are horrible, button backlighting doesn't dim with the rest of the interior lights when dimmed, screen isn't as nice or as bright as previous units, super-reflecitive screen, the noise issues mentioned above, no true dual-zone for my headrest monitors, no XM tuner, having to jump through all kind of hoops just to get music to continue playing where it left off when restarting the car, etc). When I add up all of these "cons", I'm just not sure the Android unit is worth it for me. I'll probably be going back to my WinCE head-unit very soon (Dynavin N7 or Rosen GM1010/1210). The WinCE units are not as flexible as the Android units, but the sound quality is more important to me.
I'd *gladly* pay more for a higher-quality Android head-unit, but right now, they just don't seem to exist - which is unfortunate...
jtrosky said:
Ah - I see. Interesting - so just a different antenna resolved your issue. Like you said, I guess it's spreading out the signal enough to avoid causing the interference. I'm sure someone else will find that info very useful in the future!
My noise issues are not realted to wifi. I have interference noises in the following situations:
1. If car is not running and radio LED backlighting is on (cuases a hum through the speakers). Mainly only noticeable when no music is playing (between songs, for example) or when there are very quiet parts of the music.
2. When using my headrest monitors.
3. Anytime the system accesses USB devices. The interference is pretty noticeable when reading/writing USB thumb drives - especially if they have LEDs on them.
4. If I my Eonon USB dashcam is active, it makes a strange intference noise from the speakers. Again, really only noticeable when no music is playing, but...
None of these are huge issues in of themselves, but at the same time, it just bothers me knowing that the interference exists. I've also noticed that the overall sound quality just isn't as good as my previous WinCE-based head-units - (much more expensive units - they have 4v preouts, higher-quality DAC's, etc) - even when using an external amplifier. Never had interference noises with them, so the Android unit is really a downgrade in terms of sound-quality, which is more important to me than having Android, I guess. I was hoping that there woulnd't be much difference in sound quality when using an external amp, but there still is...
At first, I thought the Android head-unit was awesome while testng "on the bench" - until I connected it in-car and used it for a few days, then I started noticing all of the "cons" (warning chimes and turn-signal sounds are horrible, button backlighting doesn't dim with the rest of the interior lights when dimmed, screen isn't as nice or as bright as previous units, super-reflecitive screen, the noise issues mentioned above, no true dual-zone for my headrest monitors, no XM tuner, having to jump through all kind of hoops just to get music to continue playing where it left off when restarting the car, etc). When I add up all of these "cons", I'm just not sure the Android unit is worth it for me. I'll probably be going back to my WinCE head-unit very soon (Dynavin N7 or Rosen GM1010/1210). The WinCE units are not as flexible as the Android units, but the sound quality is more important to me.
I'd *gladly* pay more for a higher-quality Android head-unit, but right now, they just don't seem to exist - which is unfortunate...
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Click to collapse
Hello, have you found a solution, how you fix noise ?
jtrosky said:
Ah - I see. Interesting - so just a different antenna resolved your issue. Like you said, I guess it's spreading out the signal enough to avoid causing the interference. I'm sure someone else will find that info very useful in the future!
My noise issues are not realted to wifi. I have interference noises in the following situations:
1. If car is not running and radio LED backlighting is on (cuases a hum through the speakers). Mainly only noticeable when no music is playing (between songs, for example) or when there are very quiet parts of the music.
2. When using my headrest monitors.
3. Anytime the system accesses USB devices. The interference is pretty noticeable when reading/writing USB thumb drives - especially if they have LEDs on them.
4. If I my Eonon USB dashcam is active, it makes a strange intference noise from the speakers. Again, really only noticeable when no music is playing, but...
None of these are huge issues in of themselves, but at the same time, it just bothers me knowing that the interference exists. I've also noticed that the overall sound quality just isn't as good as my previous WinCE-based head-units - (much more expensive units - they have 4v preouts, higher-quality DAC's, etc) - even when using an external amplifier. Never had interference noises with them, so the Android unit is really a downgrade in terms of sound-quality, which is more important to me than having Android, I guess. I was hoping that there woulnd't be much difference in sound quality when using an external amp, but there still is...
At first, I thought the Android head-unit was awesome while testng "on the bench" - until I connected it in-car and used it for a few days, then I started noticing all of the "cons" (warning chimes and turn-signal sounds are horrible, button backlighting doesn't dim with the rest of the interior lights when dimmed, screen isn't as nice or as bright as previous units, super-reflecitive screen, the noise issues mentioned above, no true dual-zone for my headrest monitors, no XM tuner, having to jump through all kind of hoops just to get music to continue playing where it left off when restarting the car, etc). When I add up all of these "cons", I'm just not sure the Android unit is worth it for me. I'll probably be going back to my WinCE head-unit very soon (Dynavin N7 or Rosen GM1010/1210). The WinCE units are not as flexible as the Android units, but the sound quality is more important to me.
I'd *gladly* pay more for a higher-quality Android head-unit, but right now, they just don't seem to exist - which is unfortunate...
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Click to collapse
I also wanted to hear if you found out the problem .. since I myself have the same...
I recently purchased an Erisin head unit and for the most part I'm really happy with it. It was plug and play with my BOSE system although I am a little worried I haven't attached the amp control cable (not sure where its supposed to attach) and it still works with my BOSE system despite it having separate amplifiers.
There is however a fair bit of static noise which appears to be alternator noise as there is no noise when the engine is off and increases with engine RPM. I've been told this is a grounding issue. When people say this are they referring to grounding within the amp or grounding within my car? Also would shielding the amplifier and cables help? Reducing cable length by cutting and soldering them? I believe ferrite beads can work with EMI, would they work?
The main reason for this post is to ask whether anyone has successfully used a USB DAC with a PX5 unit as I read a lot about it not working with these units. If this is possible how is this done? USB DAC going back into the RCA analogue inputs? How does the amp then know that its audio is re-routed back to itself?
Cheers,
Mike
Your grounds need to stay away from any audio signal wires and need to be as short as possible to avoid picking up noise from other wires in the car.
Also your signal wires need to be as short of a run and try to keep away from other power cords. If possible rca wires are the easiest way to reject noise but that's only if the amp will actually reject the noise that the rca pick up.
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gjkrisa said:
Your grounds need to stay away from any audio signal wires and need to be as short as possible to avoid picking up noise from other wires in the car.
Also your signal wires need to be as short of a run and try to keep away from other power cords. If possible rca wires are the easiest way to reject noise but that's only if the amp will actually reject the noise that the rca pick up.
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So should I cut the RCA outputs from the HU and solder them to the RCA inputs on the supplied harness as short as what is reasonable? Then as for grounds, I assume the ground is within the same harness as all the audio, I should find a new ground for it?
Cheers,
Mike
Do not cut the rcas there best left how they are but if you dac isn't Meant to run in a vehicle that may be your issue it's not been set up to reject noise from in a car specially if it was cheap.
if you get something like a Rockford Fosgate Punch PBR400X4D if size is an issue would be better as far as not needing to deal with so much trouble shooting to get ride of the noise.
Most car amifiers know how to reject the noise from the cables these days thru rca I'm not so sure about home audio dacs.
I'm sure it is possible to do what you want to do but your going to probably need every trick to stay away from putting noise into the lines.
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gjkrisa said:
Do not cut the rcas there best left how they are but if you dac isn't Meant to run in a vehicle that may be your issue it's not been set up to reject noise from in a car specially if it was cheap.
if you get something like a Rockford Fosgate Punch PBR400X4D if size is an issue would be better as far as not needing to deal with so much trouble shooting to get ride of the noise.
Most car amifiers know how to reject the noise from the cables these days thru rca I'm not so sure about home audio dacs.
I'm sure it is possible to do what you want to do but your going to probably need every trick to stay away from putting noise into the lines.
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Sorry I maybe wasn't all that clear. The USB dac question was separate. I'm getting alot of what I assume is alternator noise as it's only when the engine is on and increases with rpm. Interestingly it goes when the car is moving and there's no throttle. Not sure if alternators run if there's no fuel input or something.
As of yet I've determined it's a grounding issue. Does that mean grounding within the amp? The unit is an erisin unit and was supposed to be plug and play which for the most part it seems to be but I know the bose pin in the audi is to ground the HUs internal amplifier and I'm not sure it the android unit does that.
As of yet I've not tried anything so any suggestions are good.
Mike
mh5039 said:
Sorry I maybe wasn't all that clear. The USB dac question was separate. I'm getting alot of what I assume is alternator noise as it's only when the engine is on and increases with rpm. Interestingly it goes when the car is moving and there's no throttle. Not sure if alternators run if there's no fuel input or something.
As of yet I've determined it's a grounding issue. Does that mean grounding within the amp? The unit is an erisin unit and was supposed to be plug and play which for the most part it seems to be but I know the bose pin in the audi is to ground the HUs internal amplifier and I'm not sure it the android unit does that.
As of yet I've not tried anything so any suggestions are good.
Mike
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Click to collapse
Yes the alternator will usually run all the time except in newer vehicles .
Ok that's good that you don't need to figure out if it's signal going to an external amp. Have you tried emailing the maker it shouldn't be an issue with ground inside the hu.
I'm surprised no one else is commenting on this but from this point I'd have to see pictures of what's going on and maybe a drawn out wire diagram.
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gjkrisa said:
Yes the alternator will usually run all the time except in newer vehicles .
Ok that's good that you don't need to figure out if it's signal going to an external amp. Have you tried emailing the maker it shouldn't be an issue with ground inside the hu.
I'm surprised no one else is commenting on this but from this point I'd have to see pictures of what's going on and maybe a drawn out wire diagram.
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Aye I'd assume they would but if I go down a hill and take my foot off the throttle, so the ecu would cut out the fuel supply, I'd assume the alternator would be generating a current as the engine is still moving but the noise stops.
Actually maybe I shouldn't sound so confident, my browsing of forums suggests it's a grounding issue but I actually have very little knowledge of electronics. All I know is that I've taken out an Audi Rns-e OEM head unit in a car with separate OEM installed amplifier as part of the bose sound system upgrade.
There's no noise when the engine is off, the noise starts when the engine is turned on and is effected when you turn screen brightness up, and when you touch the screen. It also increases with rpm. There is a range of low and high frequency noise.
The head unit bought:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/383205297789
They have offered me a refund if I want it but I do actually like the unit, the sound quality isn't bad and the functionality is so good. So if it's something I can fix Id rather fix it. They've suggested using a high to low converter in what I think is using the amps amplifier and converting that input back down to use as the line input for mine but I see no point in having a good amp to do that. But I suppose that should give some insight into where the issue comes from.