Audio kit with network functions
Dear Forum Members,
I have decided to make something for myself. As I'm not happy with the market offerings (reasonably priced and accessible to me) of devices called streaming players, I decided to make something that would satisfy me. The basic premise was to design an audio track - reasonably good, but no fiddling - with a DAC added. This took the form of a single board. A controller (Cortex-M0) with a display is still to be made, topped off with a Raspberry Pi as a digital audio service centre (probably also with a display). Optionally, I may add some kind of UKF tuner with digital output to the set.
The attached files show the current state of the project and here I ask for everyone's feedback. It's well known that one pair of eyes often won't spot a mistake, and I'm hoping that maybe someone will see what I've missed.
Regards
.
I have decided to make something for myself. As I'm not happy with the market offerings (reasonably priced and accessible to me) of devices called streaming players, I decided to make something that would satisfy me. The basic premise was to design an audio track - reasonably good, but no fiddling - with a DAC added. This took the form of a single board. A controller (Cortex-M0) with a display is still to be made, topped off with a Raspberry Pi as a digital audio service centre (probably also with a display). Optionally, I may add some kind of UKF tuner with digital output to the set.
The attached files show the current state of the project and here I ask for everyone's feedback. It's well known that one pair of eyes often won't spot a mistake, and I'm hoping that maybe someone will see what I've missed.
Regards
.
Comments
On the raspberry a ready-made system will you use? Or something of your own? [Read more]
. Probably standard raspios. Quite a few libraries will be needed, so support is important. A few applications will need to be written, a remote desktop for these games will be useful. I don't know yet... [Read more]
As an FM tuner I strongly recommend the TEF6686 or the better TEF6687. You can test how it works with the right antenna. [Read more]
. I was tentatively considering the Silabs Si4743, but will look at what you suggest. Thanks. [Read more]
If you can, change the position of audio power circuits and sockets - to the other side of the PCB; then you will have the components on one side, thus the PCB assembly in the enclosure will be simpler,... [Read more]
I have made this arrangement deliberately. The connectors are planned on the rear wall of the case, of course, and above them, from the surface of the board upwards, I want to mount an outward projecting... [Read more]
Thank you for sharing the whole project! That's very kind of you. There are indeed quite a few modules, but looking for one, I wasn't quite satisfied either. If you drop me a PM, I'll send a small gift,... [Read more]
@gulson, unfortunately this is not the whole project yet, there will be at least one more album. The draft of the first disc, after the last corrections, flew the net (along with the corresponding amount)... [Read more]
I really like the layout although for now you have a stereo power amplifier with three analogue inputs, two digital inputs and digital volume control - unfortunately no control panel yet. As a project... [Read more]
. Thanks for your kind summary. You're very right in your comments, but with constructions like this that are singular and not based on previous experience, it's difficult to make precise assumptions... [Read more]
Interesting project. A question out of curiosity - why have resistors R93, R96 been included between the outputs of stabilisers U20, U21 and filter capacitors C97, C99? Do they not negatively affect the... [Read more]
. The data sheets for the LM337 and LM317 state to use an electrolytic or tantalum capacitor at the output, and such have ESRs of 100 milliohms or more. I inserted MLCC capacitors there with a negligible... [Read more]
. Where do you get such information from? A resistor is used if the charging current to the capacitor is likely to be destructive, in practice these are systems fed directly from the mains and the capacitor... [Read more]
manufacturer analyses (and more) suggest such a solution, e.g.: https://www.ti.com/lit/an/snva167a/snva167a.pdf https://www.ti.com/lit/an/slva115a/slva115a.pdf?ts=1726650016478 https://electronics.stackexchange.com/questions/258854/choosing-capacitors-for-a-linear-voltage-regulator ... [Read more]
To plant baboos in TI documentation? (second link). In the second figure (Figure2) the ESR unit is µF :) . Besides; it is clear from the description that the low ESR problem only affects old LDO... [Read more]
. The LM317 and LM337 circuits are from a time when large MLCC capacitances were not used (as can be seen in the data sheet in the description of the output capacitors). I prefer to take precautions,... [Read more]
These dilemmas with 0.1Ω and quibbles about the coupling loop in the stabiliser date back to the days when MSI digital circuits required a 100nF capacitor at each cube. At that time, with just 10 such... [Read more]
Interesting project - control from smartphone will be too? Description of the project interesting - could be an inspiration for someone else. [Read more]
I can write with satisfaction that the thing has moved and is playing! https://obrazki.elektroda.pl/2517939400_1728460162_thumb.jpg . In the photo you can see how it came out. You can also see the... [Read more]