RGB LED Music Spectrum Analyzer - Transparent Acrylic Sound Sensing Display with Reduced Pressure Column for Audio & Electronic Enthusiasts | Perfect for Home DJ Setups, Gaming Rooms & Party Lighting

I got this because I was nostalgic over a Technics receiver that had one built in when I was younger. These do not seem to be included on any components anymore and it's a shame.It works as it should, but I felt the purchase was a bit of a roll of the dice. I did not really know what I was going to get.I liked what I got. It's not perfect, but it's better than spending $800+ on Etsy.It's an actual spectrum analyzer display. Low frequencies are shown on the left and high frequencies on the right.I have not used the line-in input. I have only used the built in microphone. It tends to favor the lower end of the spectrum. There is an overall sensitivity knob that is labelled as 'level'. The color of the LED stack can be changed with the color knob. When turned all of the way to the left the color will cycle smoothly through the available options.The top of the lighted stack has a sample and hold block that does not fall as quickly as the others. It has sort of a bouncing effect on top of the other lighted blocks. This sample and hold block has a color that is independent of the other blocks in the stack. Mine shipped with the sample and hold block set to blue. There is no manual included, but searching for similar (identical?) units found some for sale listings. A handful of these had English manuals. Reading those - there is a switch or potentiometer on the back of the base that can be turned (with a small screwdriver) to set the color of the top sample and hold block. I have not tried it because I want mine to be blue and I do not want to get it stuck on some other color.Here are the things that bug me:1) Sample and hold - I should be able to disable that completely so the stack just moves without the bouncing light on top.2) Sample and hold - changing the color should be a knob on the front, not a recessed plastic switch on the back.3) There should be a 'hollow' or line mode that only lights the top block and not the whole stack4) The silk sceeen paint on the front display cracked/shrunk as it was drying and made flaws. It's only noticeable up close, but annoying.