Sabaj A10h, We have done a 8kV ESD test before send out, and passed it. Take it easy.
I have addressed this issue. But here we are.
In house testing and out sourced testing are different. Everything is tested for parameters and regulations before released. That's true.
But when we are talking about ESD problem in real world and reproduce it in our own lab. It's very different. The thing is from the regulation it only needs to pass 4kV to 8kV. When in real world it can go up to 20kV to 50kV.
And we have to understand these are not basic stuff. You can just ground the chassis and call it a day. But in some cases like this one is not that simple. To get to the end of this, it requires a lot of deeper knowledge and investigation. But on the other hand you can prevent this using some extra components willy nilly. But how many things are like this? You can't just foresee all the issue and just smash everything onto the board. That doesn't happen.
The main issue is not ESD but the potential harm to headphones. Preventing that from happening, and everything else don't really matter that much do they?
It's either isolated from earth or grounded at the input ground to upstream device.
If the voltage is too high the esd will discharge through the power supply. As it's low energy it won't cause any damage. And in our in house testing there's no failure with continuous 15KV pulses either condition.
I would think so, but the legend on the remote photo does not actually say that.So this little amp has the remote to change the volume remotely?
Really great news. I was looking for an amplifier to use with the Xbox and the TV, but getting up often to check the volume is inconvenient. Now we just wait for the measurementsI would think so, but the legend on the remote photo does not actually say that.
View attachment 123402
ADD: Here is a link to the owners manual. The remote DOES control volume.
What you are describing is more likely a ground loop among the E30, L30, and power source. Are both the E30 and L30 plugged into the same power strip or wall power outlet?Not gonna lie, I'm curious about the A10d. Specific SE DAC with a -118dB SINAD. It seems to have a better noise floor than E30. Using IEM I can hear very very faint noise when there is no music with L30+E30 - my Galaxy S9 (S9>TRS to RCA>L30) is quieter, no noise at all. Maybe a defective E30?
Thanks for your input. It can be ground loop, but...What you are describing is more likely a ground loop among the E30, L30, and power source. Are both the E30 and L30 plugged into the same power strip or wall power outlet?
It can also be radio noise captured by the rca cables. It happened to my d50s+a50s stack.Thanks for your input. It can be ground loop, but...
Yes, they were plugged in the same power strip. Even when feeding E30 by S9 using an OTG cable I got the same noise. I did some measurements with a TASCAM US-366 connected to a notebook - the measurements were made on battery and with power plugged. Didn't get any 60Hz neither harmonics. I did it with other DACs as D10S, KTB (the loudest one), M500... This and E30 were the quiest ones, but still listenable. During normal usage the noise is completely irrelevant, but some times when I doing critical listening at night I can hear it. It's nothing that I can't live with, but I would like to try different DACs and see if they are less noisy. BTW, the noise is volume dependent, but most of the time L30 is at its max (0 gain) and I control the volume via software or remote control. And it reminds more a white noise than a 60Hz hum. I'm not gonna hate either dislike E30, it just something that call my attention
update the new image for you.I would think so, but the legend on the remote photo does not actually say that.
View attachment 123402
ADD: Here is a link to the owners manual. The remote DOES control volume.
Sabaj A10h, We have done a 8kV ESD test before send out, and passed it. Take it easy.
no opa1612 is hidden below the relay board.2: It looks like the amp section is only TPA6120A and does not have the same audio circuit but does combine 2 TPA6120A 'halves' to increase current. This amp does not have the same opamp that blew up in the L30.
it's the same as L30 --- nested feedback. it is very close to the tpa6120a2. you just can't see it --- it's below the daughter board.The question is whether it is used as a buffer or integrated in the overall feedback loop.
Given the distance and speed of the used components and parts around the TPA6120A I would suspect it is used as a buffer or just have something to do with gain structures. I think the 1612 needs to be really close physically to the TPA for this to work.
The higher input resistance, the distance from the TPA all suggest it is not an L30 with a different volume control and the given that the ESD issue is because of the low input resistance and direct path to the volpot shaft (which isn't the case in this amp) it is unlikely to suffer a similar fate or even have the same issue.
Cool!!I have offered the A10h to Amir for testing if he does not already have one on the way and fits into his schedule.