Audio source/amplifier selector with VU meters

Hi guys,
As it was difficult to me to find an audio source selector combined with amplifier-speaker selector, I decided to design my own. The design is almost finished, but I'd like to have your opinion, advices, proposals, etc., to make it really helpful and good designed. The project will be 100% open hardware. Attached are the preliminary schematic, PCB, pictures of the chassis and PCBs. The design has been made using Altium Designer 20.
Some info about GND planes.... The board is 4 layer, because I had to shield all signal tracks, even they are as short as possible, and are between audio relays and the RCA connectors. That means I have no critical GNDs. I can supply pictures of all layers, layer by layer for greater clarity. Tha chassis is standard form 430x300x70mm with two knobs - one for selecting from 5 sources, and one for selecting from 3 amplifiers. I left just one speaker output, because I have one pair of speakers. Also there are 2 x VU meter drivers because the chassis hasn't its own. The power supply is linear to avoid EMI.

Best regards
Nick
 

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  • Arsov-audio-selector-01.pdf
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Hi guys,
The device is ready. Some audio measurements left to be done - noise, channel separation, etc.
Some pictures attached. The LCD display displays the selected source and selected amplifier.
For hobbisysts - all files are available in Altium format.
 

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  • Like
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Hi @nickarsow ,
congratulations for the project, it looks very good.
I plan to make something similar that will be able to switch 4 signal sources, 4 amplifiers, 4 speakers and maybe i will add a motorized potentiometer from alps. their control should be done with a remote control or later directly from the phone app. My problem is that I'm not a software guy, here I need to talk with a friend to help me.
From where you bought the chassis?
Happy auditions!