Technical Pro VU Meter Review

[DWPress]

I still have one of those Realistic meters from the 80's, it takes speaker level input and I've got it hooked up to my bass channels. Nice subdued bit of bling with green and red LEDs about the same size as many modern DACs.

I voted Not Terrible. Meters like this have questionable use to begin with beyond being pretty and it does that even if not accurate. With the other added functionality of USB charge port and outlet strip it is useful at least compared to many other units like this. Just run an unbalanced input into this thing with some Y cables and don't use the output then you've got something useful, bling and no distortion at any level going to amps.

 

[norcalscott]

Radio Shack actually made a similar item back in the 80s that was somewhat useful and functional. Minus the outlet strip thing on the back.

I remember them being hooked up in the store, and it actually SHOWING a relatively accurate decibel rating.
Not perfection, but why can it not be done today, with even radio shack accuracy....sad.

Hahaha I used to have one of those and it was quite impressive - At the time I had a 12 volt power supply and a car stereo system in my room (I was in middle school) with car speakers (6x9's) that I built boxes for. This Radio Shack thing gave that whole ghetto sound system a bit of "class"

 

[Gregg Hermetech]

Crookwood.

hmm....

I've been using the large rack mount Crookwood VU meter daily for 11 years now, I love it.

 

[Andysu]

This is a review and detailed measurements of the Technical Pro dB30 LED VU/bar graph meter, outlet strip and USB charger. It is on kind loan from a member and sells for $59.
View attachment 186767

I really like the 1U rack form factor and solid metal box. The functionality is excellent with USB charging port in the front and outlet strip in the back:

View attachment 186769

So this is not just some pretty lights that take up space. You would replace your power strip with it and get a bonus level meter.

Technica Pro DB30 Measurements
The problem with previous budget VU meters we have tested is that they severely load down the input causing it to distort. Let's see if we have the same problem here:
View attachment 186771

There are two gain potentiometers (on the right) that are set to the detent center position as shipped. Using that, the analyzer starts to distort above 1.2 volt (blue line). Specification is 1 volt input so you could say that is fine but just about every DAC we have outputs 2 volts in unbalanced mode so we care what happens there.

Fortunately, if you reduce the gain with those pots so that 1 volt is the max on the LED, there is no impact at all on the device feeding it. But then you have a problem. All the LEDs shut off then at -16 dB. This is not much range and totally contrary to the markings indicating 5 dB to 140 dB. They are saying 135 dB range but we are only getting 16.

That is not the only problem. The major issue is instability. If I just set the analyzer to a level of say -5 dB, the LEDs jump forward and back by as much as 5 lights! Was hard to capture the full range with my camera but this should give you an idea:
View attachment 186773

Wait a few seconds and you get this:

View attachment 186774

The thing was just dancing back and forth with input level not changing at all. It would actually light up two red LED at times.

I don't know what you do with a VU meter which dances around on its own. And with such limited dynamic range.

Conclusions
A marketing genius came up with this functionality and another genius produced it so sells for just $59. If it only worked and did something useful, it would be a killer. But sadly, it doesn't work. I suspect it would only cost a bit of money to put a proper buffer in there and get rid of noise/oscillation and make this work. Hopefully they read this and fix the issues.

I can't recommend the Technical Pro dB30. I don't need an instrument here but do need stability of the display and wide dynamic range.

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i think has do with IC chip
i have something claims be american audio
the sensitivity response looks a bit compared with other vu led lcd meter displays cheap but bit of gimmick , so now i have to figure it out , cat litter box or let my cats Magic and Bear play with it

 

[Andysu]

Amir again saving us from wasting our money. Hooray!

if only i saw this post few no days earlier lol

 

[pseudoid]

I think @amirm may have that syndrome where people get hypnotized by flashing red-lights at intersections and freeze.