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.
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:
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:
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:
Wait a few seconds and you get this:
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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As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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:
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:
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:
Wait a few seconds and you get this:
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.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/