Thanks for the feedback!
I just got an OPZ and on my first session with it I noticed the LED noise (not the usb charging noise). I then searched to see if anybody else has noticed this and here I am. So do all OPZ have the LED noise problem? or is it that the ones with LED noise are faulty?
Ehr, as you can read in this thread, thereās some evidence, that excessive led noise is not general, all units problem. But, you can contribute to this issue with asking for replace faulty unit and to let us know if the problem still exist with new unit.
I personally returned my OPZ and still waiting for some budget to rebuy (even that have I find out I can live without it 
). If Iāll rebuy, Iāll write here feedback, too.
Important thing is, to write to TE, that you have this problem and you want unit without this issue-more people will give this feedback, (I hope) more probability is, that they will take care of it (in some future?). Also, say this to your retailer, to not give your unit to somebody else (but to send back to TE). You may use this forum thread as reference of this problem, with official TE statement that they also consider it as not normal noise, too.
Good luck and please write back if youāll have new one.
Hello,
I am having the same problem and can hear the exact same noise as in the original posterās video when the LEDs are on.
I have only had my OPZ for a few weeks and I love it but this makes it pretty much unusable so I am going to contact TE and Andertons who I bought it from in the UK and get it swapped.
I will report back when I get the new one if it has the same problem.
ground loop isolator.
Hey and thanks for posting. I can hear the noise in your video, too.
I got my OP-Z yesterday and noticed that when using the microphone for sampling, a similar type of high pitched noise bleeds into the recorded signal.
This is an issue that can be experienced with different kinds of electronics and is often called ācoil whineā. You can experience it with certain phone chargers, lamps, power supplies, mainboards, graphic cards, etc. and is mostly depending on the workload the device is doing. So the device might squeal when idling, but shuts up when under load or the other way round, depending on many factors. (Some phone chargers are almost inaudible but start to squeal as soon as the phone is fully charged)
Itās a problem that many manufacturers are fighting against since decades and seems to be very complex depending on many other components used in the same system.
This has nothing to do with ground loops, since it can be found on (battery powered) devices without any connection to the mains supply, even with no connection to anything.
For me itās like partaking in a lottery each time when buying new gear:
Sometimes it helps to buy the same device twice and compare both, keep the better one, inform the dealer and manufacturer and return the faulty one. This is when youāre āluckyā and the reason is quality tolerances in the used electrical parts. If itās not and all the devices have the same problem, youāre out of luck though ā¦
on the OP-Z you have to deal with 2 thingsā-USB noise (avoid it by turning off battery charging or charge the battery before use) and the other one is a normal Feedback behavior between the mic and the speaker when the volume is turned up while recording and no line out jack is connected.
try to record something with volume down or put your thumb over the speaker holes.
Sorry but I have to disagree with you here.
This is neither a ground loop, nor a feedback loop problem.
The noise I described can be heard when having the OP-Z not connected via USB (no ground loop) and having headphones plugged in (no feedback loop, since the monitoring happens via the headphones and not the speaker).
So we have now at least four kinds of origins:
-
Noise that can be heard by holding the device to your ear (LEDs, CPU, whatever might be the cause)
-
Noise that bleeds into the microphone input due to bad shielding(?) which also gets recorded
-
A loud(!!) feedback noise that happens when monitoring the microphone input via the OP-Z-onboard speaker which can be solved by reducing monitoring volume, or using headphones
-
A buzzing/humming noise that comes when the OP-Z is connected via USB and charging which can also be solved by disabling USB-charging on the OP-Z (havenāt experienced this yet, but was definitely mentioned here on this thread)
This is the noise I am getting when recording via the internal microphone (please use headphones):
I gradually increased the the input gain of the OP-Z to make it very clear, but even with 0db of gain, the whining noise is audible.
I understand
It sounds like digital noise bleeding into the input analog signal path. It could be a fault codec IC or some other component, like a supply voltage filtering capacitor. It is a QC issue, TE call themselves āengineersā but donāt seem to be very good at thatā¦
Bolandross, so you donāt have this led noise problem (i.e. noise coming to output based on/reflecting led activity), but have the other?
TE really should take better care of shielding/QC with products which deals with sound.
And please, are there someone who exchanged OPZ after returning based on āled noiseā and have unit without this noise? Iām still interested in OPZ, but checking my chances to have noise-free unit
Hey Peter,
when using my headphones, Iām unable to hear the LEDs as you presented them in your video.
Iāll try to test again by connecting the OP-Z to my audio interface tomorrow and see if this changes anything. I have another theory that this might also be due to a different firmware version that you might have had on your device months ago. I updated to 1.2.8 yesterday, which might have changed something ā¦ but donāt let me fuel your hopes without having any proof.
Regarding my problem, Iāll contact TE and see what they say.