I have a WONDOM/Sure JAB3+ amp and the demo program causes a thump on the line output when there is no signal every few minutes. It is a double thump. Biphasic?
I created a subwoofer program based off their demo and it does the same thing.
Clicking the mute button does not fix it. Disconnecting the external speaker amp from the JAB3+ does fix it which makes me think the problem is with the JAB3+ not the external amp.
Has anyone else experienced anything similar?
Playing music at really low volume also prevents it.
I created a subwoofer program based off their demo and it does the same thing.
Clicking the mute button does not fix it. Disconnecting the external speaker amp from the JAB3+ does fix it which makes me think the problem is with the JAB3+ not the external amp.
Has anyone else experienced anything similar?
Playing music at really low volume also prevents it.
I have found the answer.
http://www.audiodevelopers.com/jab3-250-wifi-speaker/
There is a microcontroller which is dedicated to monitoring the input signal and turning off power to the ADAU1701 if nothing is detected for a few minutes to save power when batteries are used.
It seems this is the cause of the thump on the lineouts which basically makes it unusable. The internal power amp does not seem to be affected by this so it is just really bad design.
My (somewhat unsatisfactory) solution is to solder a wire between 3.3V for the board and for the ADAU1701. This bypasses the high side switch controlled by the PIC. See attached photo for my fix. It does not require the heatsink to be removed. Sorry I used a black wire - kind of hard to see.
http://www.audiodevelopers.com/wp-content/uploads/2018/09/JAB3_schem.png (attached as well)
The circuit has changed quite a lot from when this was done but it is a good start.
I thought this board was pretty good until I found this. They are trying to make it do too much and focussed on the battery aspects too much. Really poor quality control on their part this has not been fixed yet. This mod will void warranty but for me it is far more important that I have a usable subwoofer amp
http://www.audiodevelopers.com/jab3-250-wifi-speaker/
There is a microcontroller which is dedicated to monitoring the input signal and turning off power to the ADAU1701 if nothing is detected for a few minutes to save power when batteries are used.
It seems this is the cause of the thump on the lineouts which basically makes it unusable. The internal power amp does not seem to be affected by this so it is just really bad design.
My (somewhat unsatisfactory) solution is to solder a wire between 3.3V for the board and for the ADAU1701. This bypasses the high side switch controlled by the PIC. See attached photo for my fix. It does not require the heatsink to be removed. Sorry I used a black wire - kind of hard to see.
http://www.audiodevelopers.com/wp-content/uploads/2018/09/JAB3_schem.png (attached as well)
The circuit has changed quite a lot from when this was done but it is a good start.
I thought this board was pretty good until I found this. They are trying to make it do too much and focussed on the battery aspects too much. Really poor quality control on their part this has not been fixed yet. This mod will void warranty but for me it is far more important that I have a usable subwoofer amp
