I’m building a media streamer (Wi-fi, Pi local USB and Spotify) consisting of Volumio running on a Pi 5, RPi DAC Pro, Fosi amp and a small display for the album art.
I’ve tested the Volumio “now playing” plugin to a HDMI monitor connected to the HDMI port on the Pi. Seems to work fine.
This hardware will all go into a timber box I’ll make. I’d like this box to be as low profile (height) as possible.
What I’m after is a high resolution colour display of >=50mm in physical height. As said, I’ve proved the HDMI connection but I can’t find a small display with HDMI. I assume I can do some other protocol (SPI?) via the pass through pins on the DAC Pro?
Looking for display suggestions please.
Also looking for suggestions re a VU meter. Could be LED bars, a round (wearable I assume) LCD or god forbid (!) a back lit analogue dial. No idea re SW/HW design to make this part work as yet.
You need to be a little bit careful here. The analog VU meter is not just a moving coil meter with a VU marked dial.
To be accurate it has some pretty stringent specs including the actual meter ballistics. It is designed to present an impedance of 7k5 to a 600Ω properly terminated line. The meter itself has a resistance of 3k6 or 3k9 I forget which now and is intended to be used with a series resistor of 3k9 or 3k6 to make up the 7k5. Adjustment as to what exact level is required for 0VU is done with attenuators.
I think there are electronic Bar or Dot VU displays which simulate the definition of a VU meter electronically. These seem to have a peak hold feature which catch audio peaks and linger for a time before dropping off. Don’t quite know how this is done and have had no reason to investigate personally but I think they are sold as “VU Meters”.
I am sure a search on “VU meters” would turn up the specs and possible sources.
I actually have an analog VU meter which I made up to check audio phasing during installation and commissioning of TV studios. I remember the actual meter was purchased as a "VU meter from Farnell (now Element 14) and was pretty damn expensive.
Cheers Bob
Wikipedia article here
