Hello everyone
I tried to use the RCA Line-Level audio outputs of my Dasaita MTCD-PX5 unit to connect an external amplifier, but discovered that there's no signal coming out of them.
Do I need to enable them somewhere on the SW?
Thanks in advance
Max
Hi Max,
I am having the same issue, with Seicane PX30. I have temporarily spliced into the speaker wires since my amp can take high voltage input, however I have static/ clipping noise with high volume.
Please let me know if you figure this out!
SoakedCardinal said:
Hi Max,
I am having the same issue, with Seicane PX30. I have temporarily spliced into the speaker wires since my amp can take high voltage input, however I have static/ clipping noise with high volume.
Please let me know if you figure this out!
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Click to collapse
What did the reseller suggest.
currently in communication with support, sent them this:
I have purchased 2014 2015 2016 Subaru WRX Forester 9 inch Android 10.0 Head Unit.
There is no signal coming from the following RCA jacks:
• SUBWOOFER
• FL OUT
• FR OUT
• RL OUT
• RR OUT
They all register 0 volts using 40hz 0db test tone ¾ volume from bluetooth or auxiliary input.
Connecting AUX IN L/R to FL/FR OUT makes the cars 3.5mm aux jack work but there is still no output from the RCA jacks.
My unit has the DSP Sound System. I have seated the connector properly. All other functions are working normally.
How can I make it work?
Click to expand...
Click to collapse
they completely misunderstood my issue first go round . . will report back
SoakedCardinal said:
currently in communication with support, sent them this:
they completely misunderstood my issue first go round . . will report back
Click to expand...
Click to collapse
On my side, I never found a solution. Played around with several settings, but nothing...
Could this be a ROM issue?
Let me know if they ever reply back
marchnz said:
What did the reseller suggest.
Click to expand...
Click to collapse
maxiauer said:
On my side, I never found a solution. Played around with several settings, but nothing...
Could this be a ROM issue?
Let me know if they ever reply back
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Click to collapse
so . . they basically tried to bribe me $50 to stop bothering them.
I think I might be able to fix the crackliing by using my amp to sum the L + R speaker outputs instead of my homade y splitter from the stock speaker cables at the headunit . .
Sorry for the resurrection, but I just fixed this issue on my PX5 for anyone else running into this problem. TL;DR is that the harness does not have the RCA for Rear speaker outputs wired in but the PX5 DOES have the pins for it. The solution is to wire them into the harness.
SOLVED: Rear RCA Outputs for MTCE PX5
Edit: TL;DR The wiring harness does not have Rear RCA outputs (only front and subwoofer). I had to splice in the RCA for the rear because there are pins outputting signal. (See solution below for details) I'm running Hal9K Mod with Android 10...
forum.xda-developers.com
Hey guys!
I've just bought a PX5 Android head unit to Skoda Octavia 3, instead of MIB1 Bolero. Everything works fine, it's fast, but I have 2x2ch amps in car.
RCAs don't give any signal at all..... Nor rear or front, neither sub RCA-s. Wiring is perfect.
In Factory menu i could find a Power Amplifier Settings menu, but it's gray, can't be opened.
In the scroll down menu, no possibility to activate AMP.
Remote switches both amps, connecting a phone via 3,5mm jack to amplifiers, it works fine. When I connect back to the head unit, it stops working. I can only hear it working like 5% of the sound it should...
We measured if there is rupture with multimeter, we measured 0... no beep. Moreover we tried to measure the outcoming signal, but nothing. it's 0,00. On every RCA. Anyone any tips?
kukoladam said:
Hey guys!
I've just bought a PX5 Android head unit to Skoda Octavia 3, instead of MIB1 Bolero. Everything works fine, it's fast, but I have 2x2ch amps in car.
RCAs don't give any signal at all..... Nor rear or front, neither sub RCA-s. Wiring is perfect.
In Factory menu i could find a Power Amplifier Settings menu, but it's gray, can't be opened.
In the scroll down menu, no possibility to activate AMP.
Remote switches both amps, connecting a phone via 3,5mm jack to amplifiers, it works fine. When I connect back to the head unit, it stops working. I can only hear it working like 5% of the sound it should...
We measured if there is rupture with multimeter, we measured 0... no beep. Moreover we tried to measure the outcoming signal, but nothing. it's 0,00. On every RCA. Anyone any tips?
Click to expand...
Click to collapse
Send it back under warranty.
marchnz said:
Send it back under warranty.
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Click to collapse
The problem is, that is another week of waiting. I am in connection with the supplier, he asks the manufacturer about the problem. The way is good, since when I plug Front left to the Front left of the amplifier, I head very very weak sound from the front left speakers. But the outcoming signal is unmeasurable. In addition, in the Factory menu there is an option "Power Amplifier Settings", which is gray. Can't be reached..
Maybe somehow it is disabled in the menu, but I could not find in 3 hrs where.
kukoladam said:
Hey guys!
I've just bought a PX5 Android head unit to Skoda Octavia 3, instead of MIB1 Bolero. Everything works fine, it's fast, but I have 2x2ch amps in car.
RCAs don't give any signal at all..... Nor rear or front, neither sub RCA-s. Wiring is perfect.
In Factory menu i could find a Power Amplifier Settings menu, but it's gray, can't be opened.
In the scroll down menu, no possibility to activate AMP.
Remote switches both amps, connecting a phone via 3,5mm jack to amplifiers, it works fine. When I connect back to the head unit, it stops working. I can only hear it working like 5% of the sound it should...
We measured if there is rupture with multimeter, we measured 0... no beep. Moreover we tried to measure the outcoming signal, but nothing. it's 0,00. On every RCA. Anyone any tips?
Click to expand...
Click to collapse
As @marchnz .... send it back under warranty.
Every head unit I have ever had, there is no turn-on for the RCA's because they are already on. That includes my old px5 and new px6.... and I have been using RCA outs only for probably the last 40 years
What you could do is check the pins directly on the head unit plug to see if there is anything there. When you probe it with the multimeter try using a ground inside the machine instead of the ground on the plug.
Bob_Sanders said:
As @marchnz .... send it back under warranty.
Every head unit I have ever had, there is no turn-on for the RCA's because they are already on. That includes my old px5 and new px6.... and I have been using RCA outs only for probably the last 40 years
What you could do is check the pins directly on the head unit plug to see if there is anything there. When you probe it with the multimeter try using a ground inside the machine instead of the ground on the plug.
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Optical toslink between audio equipment is highly preferred.
Even with a common grounding point for -all- connected equipment the chance of an unsnubbed high frequency feedback loop is real.
If so it will likely blow all your twitters and possibly the power amp in seconds*.
If the amp's big enough you'll see smoke and fire
At the very least use a common grounding point for all pieces of equipment. Use heavy gauge wire and keep the wire length as short as possible.
*A high frequency typically 40hz or higher feedback loop when fed into and/or through a power amp will result in a huge wattage output at that frequency. It will cause the speaker bypass to shunt all of it through your tweeters and effectively short out the power amp
You probably know much more about this than I do, but a few things don't make sense to me. You said high frequency feedback loop, but then referenced 40hz. Did you mean 40khz? 40hz is a pretty low frequency and I would think would be cut out by both integrated HPFs and amp level HPFs. I am very familiar with toslink as I use them between my PC and home audio amplifier, but I've never heard of them used between a head unit and amp. Every head unit and amp I've ever owned have used RCA outputs. I'm not saying the risk isn't there but why would both head unit and amp manufacturers not use them if RCA is so dangerous? It really is an honest question, so please don't take offense.
blackhawk said:
Optical toslink between audio equipment is highly preferred.
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Well... toslink is preferred in high end equipment (bandwidth suffers in the cheap stuff).... and I would not describe these head units as "high end"
blackhawk said:
Even with a common grounding point for -all- connected equipment the chance of an unsnubbed high frequency feedback loop is real.
If so it will likely blow all your twitters and possibly the power amp in seconds*.
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Click to collapse
I think you misunderstand. I'm asking OP to look for a common ground FOR TESTING with his multimeter. If all the rca's are not working then there is a chance that something common (like the ground on the rca jacks) is broken.
objecttothis said:
You probably know much more about this than I do, but a few things don't make sense to me. You said high frequency feedback loop, but then referenced 40hz. Did you mean 40khz? 40hz is a pretty low frequency and I would think would be cut out by both integrated HPFs and amp level HPFs. I am very familiar with toslink as I use them between my PC and home audio amplifier, but I've never heard of them used between a head unit and amp. Every head unit and amp I've ever owned have used RCA outputs. I'm not saying the risk isn't there but why would both head unit and amp manufacturers not use them if RCA is so dangerous? It really is an honest question, so please don't take offense.
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RCA's are mostly used on automotive head units. They have been around for decades. toslink is the new kid on the block and there are a lot of problems with it... frequency issues, sample matching issues, select few apps to use toslink with... yadda yadda. Personally speaking, I wouldn't use toslink instead of rca in a million years. Now it does have the advantage of less noise pickup on long runs of cable, but manucacturers like pioneer, alpine, kenwood... etc have combatted the noise issues with high voltage output from the rca's (pioneers are now 4 volts peak to peak on the rca's while android is still something like 1.4 volt PtoP). Then on the other hand with toslink you need HIGH QUALITY dac's to avoid sample and frequncy issues... and these android head units are NOT what I would describe as anywhere NEAR "high end"+
toslink.... not me thank you... not at this low price level anyway.
As for blowing tweets with stray "40hz" signals.... hasn't happened to me in 40 years of using rca's
Bob_Sanders said:
Well... toslink is preferred in high end equipment (bandwidth suffers in the cheap stuff).... and I would not describe these head units as "high end"
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Click to collapse
Just a friendly old school warning so peeps never learn what driver coils smell like...
Cheap stuff will likely have less design fedback safeguards than high end equipment.
Regardless of the amp's frequency response the fed back will be on the high end. 10khz would still behave like 60khz as far as the crossover is concerned.
Regardless its best to wire/ground it proper for best performance and minimal voltage drops... wire is cheap.
I have a friend that saw this happen on a high end system. All they heard was a static like noise and in less than a second the tweeters were smoking. A couple hundred down the drain. It can get real expensive fast and by the time you realize it's happening, it's already done.
Yeah, I don't think anyone sees these as high end in the audio production department. I think they have become somewhat popular because a lot of the main players in audio head units have been a little slow in the freedoms that Android provides in terms of apps, navigation, etc. They are too busy pushing their proprietary interface crap.
blackhawk said:
Just a friendly old school warning so peeps never learn what driver coils smell like...
Cheap stuff will likely have less design fedback safeguards than high end equipment.
Regardless of the amp's frequency response the fed back will be on the high end. 10khz would still behave like 60khz as far as the crossover is concerned.
Regardless its best to wire/ground it proper for best performance and minimal voltage drops... wire is cheap.
I have a friend that saw this happen on a high end system. All they heard was a static like noise and in less than a second the tweeters were smoking. A couple hundred down the drain. It can get real expensive fast and by the time you realize it's happening, it's already done.
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Click to collapse
You can blow a simple ic chip with static so we shouldn't use them? Freak things happen. That's life.
Bob_Sanders said:
You can blow a simple ic chip with static so we shouldn't use them? Freak things happen. That's life.
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Click to collapse
No that's ignorance and ineptitude.
I handled thousands of IC's and flat packs without damaging them by heat or ESD.
On a high end system with 7 mains blowing them out alone would be over $2G in replacement parts.
Anything worth doing is worth doing right.
objecttothis said:
Yeah, I don't think anyone sees these as high end in the audio production department. I think they have become somewhat popular because a lot of the main players in audio head units have been a little slow in the freedoms that Android provides in terms of apps, navigation, etc. They are too busy pushing their proprietary interface crap.
Click to expand...
Click to collapse
Well... as far as I know the higher end units are still going RCA..... and if there is ever a change I suspect toslink will be passed over in favor of the MUCH BETTER hdmi standard anyway.
Related
I have an Xtrons PF75ATTAR and it has developed a fault. It boots up fine and everything works as it should however there is no sound.
I have reinstalled the original Audi head unit and this works fine so the fault seems to lie with the Xtrons unit.
I contacted Xtrons and as I am not the original purchaser they can offer no support at all and suggested I buy a new unit. It is just still within 12-months warranty so I am trying to get hold of the guy I bought it from to see if he can arrange an RMA, however I need to try other options just in case I can't get hold of him or he won't cooperate.
I am not much of an electronics person (I have a soldering iron and a multimeter....) so I am not sure how to troubleshoot this.
The unit has a 'dongle' between the audio out on the rear of the head unit. This is encased in heat-shrink and I am not sure what it does, but is inline with the audio outs so I am wondering whether it might be this that is at fault?
Any help is appreciated
Andy
ADB100 said:
I have an Xtrons PF75ATTAR and it has developed a fault. It boots up fine and everything works as it should however there is no sound.
I have reinstalled the original Audi head unit and this works fine so the fault seems to lie with the Xtrons unit.
I contacted Xtrons and as I am not the original purchaser they can offer no support at all and suggested I buy a new unit. It is just still within 12-months warranty so I am trying to get hold of the guy I bought it from to see if he can arrange an RMA, however I need to try other options just in case I can't get hold of him or he won't cooperate.
I am not much of an electronics person (I have a soldering iron and a multimeter....) so I am not sure how to troubleshoot this.
The unit has a 'dongle' between the audio out on the rear of the head unit. This is encased in heat-shrink and I am not sure what it does, but is inline with the audio outs so I am wondering whether it might be this that is at fault?
Any help is appreciated
Andy
Click to expand...
Click to collapse
Hi there, do you have any pics of this "dongle"?
I'm just wondering if the speaker outputs have been converted to a low level output so they can be used as a line-in on an amp. If this is the case then the speaker outputs will have been spliced and effectively diverted from the loom which would result in no sound until you either use the converted outputs into a separate amp or reconnect them to the original wires so that you use the standard speaker outputs from the head unit.
I may be well of the mark here but seeing as I have just completed an install in my friends van with this same "spliced" setup, its worth checking out.
sirleeofroy said:
Hi there, do you have any pics of this "dongle"?
I'm just wondering if the speaker outputs have been converted to a low level output so they can be used as a line-in on an amp. If this is the case then the speaker outputs will have been spliced and effectively diverted from the loom which would result in no sound until you either use the converted outputs into a separate amp or reconnect them to the original wires so that you use the standard speaker outputs from the head unit.
I may be well of the mark here but seeing as I have just completed an install in my friends van with this same "spliced" setup, its worth checking out.
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I didn't take these pictures myself, however this is the dongle.
It was working fine for about 6-months and I haven't changed anything. I got in the car one day and there was no sound. After about 20 minutes I started to hear some pops and feint audio. I stopped the car and turned the ignition off for a minute or so and then started it back up and the sound returned. The next time I got in the car there was no audio and stopping and starting didn't fix it.
ADB100 said:
I didn't take these pictures myself, however this is the dongle.
It was working fine for about 6-months and I haven't changed anything. I got in the car one day and there was no sound. After about 20 minutes I started to hear some pops and feint audio. I stopped the car and turned the ignition off for a minute or so and then started it back up and the sound returned. The next time I got in the car there was no audio and stopping and starting didn't fix it.
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Click to collapse
Ok, that's not what I was thinking....
That looks like the breakout for your line-out, do you run an amp with your head unit or just use the internal amp?
Your description of pops and feint audio with eventual lack of audio sounds like something has blown
sirleeofroy said:
Ok, that's not what I was thinking....
That looks like the breakout for your line-out, do you run an amp with your head unit or just use the internal amp?
Your description of pops and feint audio with eventual lack of audio sounds like something has blown
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My car has a Bose amp (factory fit).
Any ideas how to troubleshoot?
ADB100 said:
My car has a Bose amp (factory fit).
Any ideas how to troubleshoot?
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Click to collapse
Ok, I'm not familiar with Audi setups but I'm guessing the Bose amp still requires a 12v remote to switch it on, usually a blue wire from the head unit. Could be worth checking that for 12v on ignition.
My PX5 unit effectively has 2 blue remote wires, one called "ANT" and one called "AMP SWITCH" or something like that..... might be worth swapping those over if you have two like I do.
How is audio supplied to the amp? Is it via the line out RCA's or via the loom/harness?
Another thing to look at, and I know this will sound super silly but on my unit a couple of the connections on the rear are similar to one another and it could be relatively easy to plug something into the wrong port. I did it and wondered why my USB didn't work! I'm sure this is not the case but still worth checking.
sirleeofroy said:
Ok, I'm not familiar with Audi setups but I'm guessing the Bose amp still requires a 12v remote to switch it on, usually a blue wire from the head unit. Could be worth checking that for 12v on ignition.
My PX5 unit effectively has 2 blue remote wires, one called "ANT" and one called "AMP SWITCH" or something like that..... might be worth swapping those over if you have two like I do.
How is audio supplied to the amp? Is it via the line out RCA's or via the loom/harness?
Another thing to look at, and I know this will sound super silly but on my unit a couple of the connections on the rear are similar to one another and it could be relatively easy to plug something into the wrong port. I did it and wondered why my USB didn't work! I'm sure this is not the case but still worth checking.
Click to expand...
Click to collapse
The audio is supplied to the amp via a quad-lock connector. So the audio from the rear of the unit connects to this dongle on one side, out the other side of the dongle are four female RCA's. These are connected to four male RCA's that connect to the quad-lock connector. There are two blue wires labelled 'AMP-CON' that have male/female push-fit connectors and these are connected together - I am guessing this is the 12v to switch the amp on? There is also another blue wire labelled 'ANT' with a push-fit connector. This is connected to a green wire coming out of the antenna facra cable.
It was working and nothing has been disturbed so I am fairly sure its not been wired up incorrectly. I think something has broken...
I'll check with a multimeter that I am getting 12v on the AMP-CON cable from the back of the amp first.
Andy
OK, so armed with multimeter I decided to have a play with this earlier. It does appear that the AMP-CON wire is not delivering 12V and therefore not turning the Bose amp on.
If I disconnect the 12v wire from the dual fakra antenna adapter the sound kicks in, however the radio reception is dreadful. I believe the 12V wire is there to power an antenna signal booster integral to the car. If I measure the voltage with the 12v wire disconnected from the fakra adapter its 10.something volts, if I measure it with the 12v wire connected its 0.something volts. Is it likely this fakra adapter is faulty? It looks like a passive component?
Cheers
Andy
ADB100 said:
OK, so armed with multimeter I decided to have a play with this earlier. It does appear that the AMP-CON wire is not delivering 12V and therefore not turning the Bose amp on.
If I disconnect the 12v wire from the dual fakra antenna adapter the sound kicks in, however the radio reception is dreadful. I believe the 12V wire is there to power an antenna signal booster integral to the car. If I measure the voltage with the 12v wire disconnected from the fakra adapter its 10.something volts, if I measure it with the 12v wire connected its 0.something volts. Is it likely this fakra adapter is faulty? It looks like a passive component?
Cheers
Andy
Click to expand...
Click to collapse
Ah good, I'm glad that you've narrowed it down! As far as I'm aware, these wires are 12v switched and are there simply to provide the signal for whatever device to turn on. If the AMP-CON wire has no voltage, you may just be able to use the same wire you use for your Antenna. I have done this before where I used the 12v switched wire from an antenna in the boot instead of running a remote wire the full length of the car.
I would be curious to find out why the AMP-CON wire does not supply voltage, it could be down to a broken wire somewhere or even a dodgy solder within the unit.
sirleeofroy said:
Ah good, I'm glad that you've narrowed it down! As far as I'm aware, these wires are 12v switched and are there simply to provide the signal for whatever device to turn on. If the AMP-CON wire has no voltage, you may just be able to use the same wire you use for your Antenna. I have done this before where I used the 12v switched wire from an antenna in the boot instead of running a remote wire the full length of the car.
I would be curious to find out why the AMP-CON wire does not supply voltage, it could be down to a broken wire somewhere or even a dodgy solder within the unit.
Click to expand...
Click to collapse
Hi, thanks for taking the time to help out. I don't think I described the cabling correctly. The AMP-CON and the ANT come from the same pin in the connector that plugs into the rear of the head unit (one wire comes out and then it splits into two and there is a bit of heat-shrink around the join. If I disconnect the ANT cable from the green wire that comes from the fakra adapter there is sound and the cable goes +10v. If I connect it back up there is a low 'thud' as it makes contact, the sound stops and the voltage drops to 0.something. It seems the fakra adapter is dragging the voltage down, hence why I think this adapter might be faulty.
Andy
I have the same issue now. We’re you able to resolve this?
I am also having this issue.. My HU turns on. Everything works perfectly... Just no sound. None at all. No factory amp. In a 2002 Silverado. I don't know if its the internal amp or what. Ideas?
Hello,
I am having trouble passing meaningful audio to a Bose factory amp from my PX5 MTCD (said amp comes with my 2013 Mazda CX-9 but I believe that the same hardware can be found in other contemporary Mazda vehicles). Instead of audio I only get a 2Hz very loud beep. The best guess (by me and the PAC guys) as to what happens is that the signal level is too high for the Bose preamp (which is known to have a low impedance) so that the amp is overloaded. I am feeding said amp directly from the preamp outputs of the unit. I believe (but I am not sure) that the way the unit is interfaced with the CAN bus is immaterial to the issue. Indeed, I connected the unit using the included CAN bus adapter as well as a PAC RP4-MZ11 adapter with the same result.
So my question is, is there a way to control the gain of the preamp outputs of such a unit? Do you guys have any other advice on what to try to fix this issue? Wild guesses are welcome (I am willing to experiment).
Thoughts are much appreciated. Many thanks!
In my Audi B7, which also uses a Bose amp like this, I used 2:1 step-down audio transformers along with a resistor divider network on the SPK out from the android headunit. I found the line out level to be too low to drive the transformers, and couldn't connect line out directly to amp due to non-isolated ground.
JAmBer99 said:
In my Audi B7, which also uses a Bose amp like this, I used 2:1 step-down audio transformers along with a resistor divider network on the SPK out from the android headunit.
Click to expand...
Click to collapse
Great tip, thank you very much. I will try it as soon as I can. Do you happen to remember the overall resistance and the ratio for the divider?
JAmBer99 said:
couldn't connect line out directly to amp due to non-isolated ground.
Click to expand...
Click to collapse
So that's what causes the trouble. Good to know, thank you again. Much appreciated.
For the record, it turned out that my issue was caused by the CAN bus adapter rather than audio source. Strangely enough, the adapter requires that the car be turned on (and that's a full on, not just ACC) for the first time. If this is not the case then max volume beeps are all the sound that is produced by the amp. As soon as the car is turned on once the amp/head unit combination will work thereafter on ACC as well as on ON.
This appears to be a "feature" of the vehicle rather than the adapter, as the same problem manifested itself with two totally different adapters (PAC RP4-MZ11 as well as the adapter that came with the head unit).
With this proviso the preamp outputs of the head unit drive the amp well, so that there was no need for a line converter in my installation. The preamp level is pretty high (so volume beyond 25% or so is unusable) but this can easily be fixed by playing with the gain on the head unit.
Hi all,
I have purchased a PX5 unit made for my 2008 Mazda 6. Unfortunately, it suffers from an issue with the audio quality. Whenever the audio level is above 0, a static/interference noise can be heard, and the pitch of this sound changes when driving, similar to alternator whine.
This is relatively loud, and can be heard even when moving or when sound is at low volume. If required, I could create a recording of the noise. I have updated the MCU to the latest available version to no avail.
I am relatively confident at soldering and am willing/able to take the HU apart to make modifications if anyone has any recomendations as to what I can do? I have seen various hardware mods floating around, but nothing that conclusively seems to say it will help with my issue.
There is also a large amount of static/interference when using Bluetooth for calls, but mainly to the party not connected to the car (IE the person calling in can hear the noise). Unsure if this is related, but the noise appears to be a similar pattern and pitch.
This issue is present both with the car running and off, and also was present on a bench power supply during testing.
Any help would be greatly appreciated!
Should be an easy fix. https://www.crutchfield.com/ISEO-rg...car/noise_suppressors_installation_guide.html
Sent from my Z981 using Tapatalk
Thanks for the post, but unfortunately the noise is present even when connected to a bench supply, with no additional interference from the car present. There is no amplifier in this scenario, so I am fairly confident the issue comes from the HU itself. I'm not sure if there may be something I can re-route or shield inside the unit to minimise it? I don't mind if I can't eliminate it entirely, but I would. Like to minimise the issue.
Thanks!
I found that I was able to remove one aspect of the noise by turning off the colour cycling of the front LEDs. This was causing a kind of pulsating low pitch siren type noise in the audio.
It appears that having the front LEDs on anything other than full power or completely off causes the noise to varying degrees.
I still have a fair amount of cracking/static type noises, but I was able to somewhat lower the volume and improve the quality by attaching RCA cables directly to the outputs of the BD37033 chip. I'm not entirely sure what occurs after this chip in terms of sound processing, as in was difficult to trace out on the PCB. Interestingly, this modification means that the static is produced even when the unit is booting or on mute, which didn't occur before. I found this odd, as the mute functionality (And all other functionality as far as I was able to tell) is retained.
I assume the signal goes back to the MCU before going out to the factory RCA outlets and amp.
If anyone knows more, I would lose to hear it!
I have the same issue: https://www.youtube.com/watch?v=gTNJVWFpBlw&feature=youtu.be
There is a static / hissing sound when the volume is on, changing volume doesn't affect it.
I might to try to upgrade the amp chip to Pioneer PA2030A from TDA7851 to see if it will fix it...
Hi.
I have the same issue with my radio in Mazda CX-9 with Bose.
Version of the radio:
PX5 Malaysk 6.0.1 MXC89L 20170901.180527 MCU VERSION MTCD_KLD_V_2.57_1 - now I have the newest version, and the problem is still the same.
I have a lot of noise when searching for something on the radio, or connecting something under USB (at the rear panel - when I'm connecting in the front - it is OK), while listening to music quietly.
What I've done so far:
1. Upgraded to the latest version of Malaysk with of course wipe all data - nothing changed.
2. Installed: anti-interference voltage filter, it works because I can not hear feedback from the car's electrical system, the alternator is not audible anymore.
3. I wrapped the cables on the back with aluminum foil plus tape insulation - nothing changed, maybe a little less noise from the radio, but still I hear all the time.
4. I connected back to the original radio - no noise - absolute silence from the speakers
The most annoying is the increasing noise of the car during driving, I have to manually adjust the volume, which does not change anyway.
Is "the cheap" radio from China, I dont know what to do.
I think that the problem is that the radio does not work well with the Bose amplifier.
I had Mazda CX-9 without Bose, and installed cheap amp with cheap radio from China - and everything worked perfect, no noises at all ! Because the amplifier was cutting out this noise with no problem.
Here the Bose amp have huge problems with that noise, I don't know why.
This noise is nothing but the noise of data transfer over the radio, which I hear all the time once more quietly and louder, as I connect, for example, a car camera to the rear USB, this noise is unbearable.
The best solution, IMHO is to remove the Bose amplifier from the car and connect the radio to another A / B class amplifier, which is much better at reducing these disturbances.
But it is a lot of work to make the whole installation work perfectly.
Me too...
I have also got this issue with my MTCD GS unit. My car has Bose also. I have tried earthing various point/things with the head unit hanging out of the dash but no change. I have also tried disabling the WiFi & Bluetooth and again no change.
I noticed the other day when I put my headlights on and the backlights on the unit came on the noise increased slightly so there might be something in the LED thing.
Andy
Exactly same thing for me too. Cheap units..
Hi.
I'll try with:
Car Stereo Audio Wire to 4 Channel RCA High to Low Audio Level Converter Adaptor
And let you know if it is OK.
I wonder, after all, the Chinese radio has a low output to the amplifier, just through the RCA plug, it can try this connection yet.
Connect to the Bose amplifier via the RCA plugs
PRODUCT FEATURES:
4 Channel Hi/Lo Audio level converter
Converts speaker level audio to line level (RCA) output
Adjustable output level to allow input to suit various amplifiers
Also eliminates signal noise
Maximum input from speaker level: 100 Watts
The noise is even related to the touch screen on my side, touching the screen changes the hiss
Removing the Bose amp and connecting a new amp with just RCA cables has improved the issue, but not eliminated it. My next step is to remove the amplifier chip entirely and see if that makes a difference (As I am only using the low level outputs I do not need the amp chip)
kaise123 said:
Removing the Bose amp and connecting a new amp with just RCA cables has improved the issue, but not eliminated it. My next step is to remove the amplifier chip entirely and see if that makes a difference (As I am only using the low level outputs I do not need the amp chip)
Click to expand...
Click to collapse
Have you tried connecting via normale speaker lines, using a HLA? -> I also have a factory amp and using the RCAs got me ground issues - not present with the normal lines, so I ordered a HLA.
You can lower the output to max -15db in factory settings which I use in the meantime..
Xorit said:
Have you tried connecting via normale speaker lines, using a HLA? -> I also have a factory amp and using the RCAs got me ground issues - not present with the normal lines, so I ordered a HLA.
You can lower the output to max -15db in factory settings which I use in the meantime..
Click to expand...
Click to collapse
Hi, thanks for the answer.
I reduced the decibels to -9dB and noticed that it is much better, but of course the noises are only less audible.
I'm waiting for High quality audio converter to RCA cables, and let you know and let if I have eliminated the noise completely.
DD
dranet said:
Hi, thanks for the answer.
I reduced the decibels to -9dB and noticed that it is much better, but of course the noises are only less audible.
I'm waiting for High quality audio converter to RCA cables, and let you know and let if I have eliminated the noise completely.
DD
Click to expand...
Click to collapse
Should recieve my HLA today and will report back aswell. I have given up on the RCA jacks from the HU though.
I found that the RCA jacks were considerably better than the speaker level outputs as far as both noise and quality go. I was already using the speker level outputs when I initially noticed the issue.
kaise123 said:
I found that the RCA jacks were considerably better than the speaker level outputs as far as both noise and quality go. I was already using the speker level outputs when I initially noticed the issue.
Click to expand...
Click to collapse
I agree. I was able to tune the the "static noise" out of my system using a 3-way electronic crossover/ line driver buy turning down its gain till the noise went away. Lost a bit of volume, but just had to turn the head unit volume up a bit more to make up for it. Not much you can do with speaker level inputs except not to use them and use external amplifiers for all your speakers.
I believe the cause of the noise is an internal isolation problem, not to sure if any isolation can be added to the inside of the unit, When the wifi was on i was getting some bad feedback as well, but i was able to tune that out as well.
Guys, I was able to install the HLA today and beside I cant bring it to clip the sound has improved regarding base.
Turned the gain little up and am now satisfied with the result.
I had a hissing noise from the start even with oem radio and this is gone aswell.
All that using the speaker lines towards oem amp.
Octane70 said:
I agree. I was able to tune the the "static noise" out of my system using a 3-way electronic crossover/ line driver buy turning down its gain till the noise went away. Lost a bit of volume, but just had to turn the head unit volume up a bit more to make up for it. Not much you can do with speaker level inputs except not to use them and use external amplifiers for all your speakers.
I believe the cause of the noise is an internal isolation problem, not to sure if any isolation can be added to the inside of the unit, When the wifi was on i was getting some bad feedback as well, but i was able to tune that out as well.
Click to expand...
Click to collapse
I also believe this is related to the inside of the unit having poor power delivery and bad isolation. Unfortunately the audio is all routed on the main PCB itself so it is not easy to isolate it. I did improve things considerably by soldering directly to the output from the BD37534FV controller and then using this as my RCA output. I did try some further digging but wasn't able to trace the source of the noise back any further.
Next I am going to try adding a capacitor to the power supply, removing the built in TDAXXX amp chip and seeing if I can improve the ground connection on the unit.
Hi.
Finally, I achieved what I wanted more or less, I reduced the number of noises to a minimum, using RCA converters from high to low voltage, adjustable at the expense of the output volume, but I made up for it with the Viper4android module, making listening to music comparable to sitting in a concert hall. Cool effects can be obtained with this module.
That's enough for me, of course, the noise is still present, but it's not as bothersome as before. I do not have the effect anymore that while driving from 100 km / h up, the noise increases and the volume stays constant.
Still, unfortunately, I can not connect anything to the rear USB, because the speakers start to tweet data transmission, similar to the transmission of the modem only faster, I have a USB webcam connected to the front of the radio, unfortunately it is annoying but at least there is no noise.
Of course, to reduce the number of noises in the car completely, I would have to exchange Chinese cheap radio, for which I paid some 300USD for some better, eg from Xtrons radio, they are supposedly better done, but I would have to play with 2DIN frames and it will not be anymore perfectly fit in place of the old radio.
Thanks
DD
This is what I use:
ESX High-To-Low Level Converter ISC4
or
HIFONICS HCV4
I have a Dasaita PX6 4gb/64gb with DSP running android 9.
It seems like the subwoofer output is very low, I performed a standard subwoofer amplifier RMS tuning,
Disconnected Subwoofer from NVX Amp, Played a 50hz test tone, and turned up the volume to the maximum on the Head Unit. Then measured the speaker output of the amp with a multimeter. Even with the Level turned up to maximum, I only got about 9 Volts. I'm expecting an RMS level of around 34 volts (sqrt (2ohm * 600RMS))
I checked the settings in the "Amplifier" app and the subwoofer gain was turned up all the way.
With the volume on the stereo at a reasonable level, I was only getting 1-2 volts output of the amplifier.
Anyone have any ideas? is this a DSP/software problem Dasaita needs to fix?
Ive got similiar problem. Any advice how to get biggher preamp for the RCA connections?
I ended up buying an RCA line input booster, like this one
https://www.amazon.com/dp/B003LWV77Y/ref=cm_sw_r_other_apa_i_ARwjDb2NE3SJX
and that solved my problem. I think the voltage that the DSP is putting out is just way too low for most amplifiers to detect and isn't getting past the amp input gate.
I think this is a software fix Dasaita needs to make if their hardware can handle it.
I just installed my head unit and now my factory alpine subwoofer in my wrangler does not work... any ideas?
@hotaudio we have at least 3 people here that are having subwoofer output level problems, can you comment?
Has this gotten fixed? I am looking at buying a PX6 4gb/64gb desaita for outlander Phev 2014.
Sent from my Pixel 3 XL using Tapatalk
No updates that I am aware of. Again I was able to work around it by buying a line level booster.
evilflame2 said:
@hotaudio we have at least 3 people here that are having subwoofer output level problems, can you comment?
Click to expand...
Click to collapse
What have you measured the line output to be at 0db to ascertain 'problem'?
marchnz said:
What have you measured the line output to be at 0db to ascertain 'problem'?
Click to expand...
Click to collapse
I thought I performed this test with a 0db 50hz test tone, I measured 9volts on my amp speaker terminals, with every volume turned up to maximum (amp, head unit, bass boost etc...)
I expected to be tuning my amp to around 34 volts. After buying the line output amplifier, I was able to accomplish a standard amplifier tuning procedure.
If there is another test I should be performing let me know how to do it. Thanks.
You really need an external aftermarket amp if your expectation is having base. These units dont have a strong amp despite there being a sub out. I have an xtrons. Basic sound was ok, with a jbl amp behind it its mental. Even on the stock speakers. There is no head unit i know of that has good base(sub) out without an external amp.
ghost010 said:
You really need an external aftermarket amp if your expectation is having base. These units dont have a strong amp despite there being a sub out. I have an xtrons. Basic sound was ok, with a jbl amp behind it its mental. Even on the stock speakers. There is no head unit i know of that has good base(sub) out without an external amp.
Click to expand...
Click to collapse
That's interesting! I have zero experience with car audio, but love good sound...what amp are you talking about specifically?
Sent from my Pixel 3 XL using Tapatalk
ghost010 said:
You really need an external aftermarket amp if your expectation is having base. These units dont have a strong amp despite there being a sub out. I have an xtrons. Basic sound was ok, with a jbl amp behind it its mental. Even on the stock speakers. There is no head unit i know of that has good base(sub) out without an external amp.
Click to expand...
Click to collapse
Sorry if I was not clear, I do have an external amp 750w NVX.
Just to get the sub signal to pass the noise gate so the amp functions, I need the line signal booster on the sub output. That is unacceptable for the price we are paying for a product like this.
evilflame2 said:
Sorry if I was not clear, I do have an external amp 750w NVX.
Just to get the sub signal passed the noise gate so the amp functions, I need the line signal booster on the sub output. That is unacceptable for the price we are paying for a product like this.
Click to expand...
Click to collapse
My unit dasaita max6 that I have ordered but not received yet is supposed work with the cars Rockford fosgate system so I imagine it will feed the amp since the RF-amp is a separate unit from the original head unit. So hopefully that won't be an issue... Anyone else with this setup that can confirm/not confirm this working properly?
Sent from my Pixel 3 XL using Tapatalk
Rawb1 said:
My unit dasaita max6 that I have ordered but not received yet is supposed work with the cars Rockford fosgate system so I imagine it will feed the amp since the RF-amp is a separate unit from the original head unit. So hopefully that won't be an issue... Anyone else with this setup that can confirm/not confirm this working properly?
Click to expand...
Click to collapse
Most amplifiers have what is called a noise gate, which basically doesn't let the sound through until it reaches a certain threshold (voltage). I guess it would depend on how your car sends the subwoofer signal from the px6 to your amp. If it uses the sub rca jack then you may run into the same issue.
evilflame2 said:
I have a Dasaita PX6 4gb/64gb with DSP running android 9.
It seems like the subwoofer output is very low, I performed a standard subwoofer amplifier RMS tuning,
Disconnected Subwoofer from NVX Amp, Played a 50hz test tone, and turned up the volume to the maximum on the Head Unit. Then measured the speaker output of the amp with a multimeter. Even with the Level turned up to maximum, I only got about 9 Volts. I'm expecting an RMS level of around 34 volts (sqrt (2ohm * 600RMS))
I checked the settings in the "Amplifier" app and the subwoofer gain was turned up all the way.
With the volume on the stereo at a reasonable level, I was only getting 1-2 volts output of the amplifier.
Anyone have any ideas? is this a DSP/software problem Dasaita needs to fix?
Click to expand...
Click to collapse
Hi
Do you know the type of the DSP chip?
I have similar problem with isudar h53 unit. The subwoofer voltage lover than the 4 cahannel voltage.
The filter can be adjusted but the gain not works on sub channel.
DSP chip BU32107EFV
vegfokic said:
Hi
Do you know the type of the DSP chip?
I have similar problem with isudar h53 unit. The subwoofer voltage lover than the 4 cahannel voltage.
The filter can be adjusted but the gain not works on sub channel.
DSP chip BU32107EFV
Click to expand...
Click to collapse
How do I determine my type of DSP chip? thanks
evilflame2 said:
How do I determine my type of DSP chip? thanks
Click to expand...
Click to collapse
I opend the head unit and checked the chips. In my case the dsp chip was on the back side of main board.
Yesterday I added a signal amplifier for two front ch and the sub ch. Now I can got 3,6V without distorsion of the two front ch but the sub ch at same volume ~2,1V. Checked 50Hz test signal. At the moment Im waiting for the seller response, what about the loudness control and sub gain control why they not work.
Did you get an answer from dasaita about this?
vegfokic said:
I opend the head unit and checked the chips. In my case the dsp chip was on the back side of main board.
Yesterday I added a signal amplifier for two front ch and the sub ch. Now I can got 3,6V without distorsion of the two front ch but the sub ch at same volume ~2,1V. Checked 50Hz test signal. At the moment Im waiting for the seller response, what about the loudness control and sub gain control why they not work.
Click to expand...
Click to collapse
I have the same problem with my sub out channel on my PX6. I upped the gain on my amp to compensate. I have a audio control amp with distortion indicator and cranked it up to about 80% gain without distortion to get good sound out of my subwoofer.
---------- Post added at 06:25 PM ---------- Previous post was at 06:22 PM ----------
evilflame2 said:
Sorry if I was not clear, I do have an external amp 750w NVX.
Just to get the sub signal to pass the noise gate so the amp functions, I need the line signal booster on the sub output. That is unacceptable for the price we are paying for a product like this.
Click to expand...
Click to collapse
Yeah the RCA sub output didnt have enough to turn on my AudioControl amp either. I ended up running the remote turn on wire to the fuse box an tapped there for switched power.
I know this issue too.
Is this caused by the hardware in the radio or is this maybe some software issue? Firmware or MCU maybe?
Hi everyone,
I bought a car and in this car there is an android auto unit.
This unit is a PX5 MTCE_CZ with Android 8.
When a call someone in bluetooth, my correspondent heard a hiss at each acceleration.
So I décide to update the unit.
Firstly, I upgrade the MCU to 2.88 to 3.41.
Secondly, I would like to pass on Android 10. For that I use SDDiskTool and CHS7_PX5_10.0_IMG(20200603).zip file.
The update seems to be ok.
But the hiss are still here and now I can't put the wifi on.
I choose the CHS7 randomly, why there is CHS, GS, HA, etc?? What is the difference between this files?
Thanks
I can't help you with the software question, but the noise in the call is probably a hardware problem. The unit seems to be picking up the electrical noise from the car (spark plug, injectors etc). It can happen thru the air (electromagnetic) of thru the wires (ground loop etc).
Noise source is not easy to find so you will have to tinker on it.
A good way to isolate the problem is powering the unit using a small 12v battery without any electrical contact with the car, but having the unit in the usual place. If you can plug a external independent speaker is even better.
If the noise goes away when you power if from a full independent battery, the noise problem can be on the main 12v or some ground loop.
Noise from power source sometimes can be solved using a big capacitor in parallel to the 12v.
Ground loop is not so obvious to figure out (search for ground loop on google).
If it still picking up noise using an external battery the problem is not in the power or ground loops, so you will need to check the overall shielding of the unit/microphone. You can start changing the cable routing and go from there...
Hi,
thanks for your answers.
I will check with your method and I give you my feedback.