Not following that. It very much does affect whether it's 'VU'. Ballistics are part of the definition.
About the "Ballistic".
There is not much of a usable definition. Apart from reverse engineer a vintage Vu meter with its driver, I did not see how to tackle this issue.
All I did was; Having a sound engineer look at it, He said it looked fine to him.
I was thinking to put a cap at the Vu meter coil in case it were too jerky.
There is not much of a usable definition. Apart from reverse engineer a vintage Vu meter with its driver, I did not see how to tackle this issue.
All I did was; Having a sound engineer look at it, He said it looked fine to him.
I was thinking to put a cap at the Vu meter coil in case it were too jerky.
Oh yes, the ballistics are part of the definition, as mentioned in my article (although not by name). But the ballistics of the meter don't affect how correct a reading it gives, long term.
Only the very best 'true' types have perfect ballistics engineered into the mechanics of the meter itself. And even then, it's a very good idea to stick a cap across the meter to ensure no nasty inductive effects of the coil play havoc with the rectifier and driving circuit if anything close to pure current drive is used.
You should only really be putting electrolytic (>1uF) values in series if there is significant overshoot. I personally prefer a slow response with no overshoot at all, but we are getting into personal preference here, as opposed to looking objectively at the VU standard
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Maybe you are used to slower meters? The non-standard meters can be very slow sometimes. Experiment with the parallel cap and find the smallest value that gives no overshoot.
Mike
Only the very best 'true' types have perfect ballistics engineered into the mechanics of the meter itself. And even then, it's a very good idea to stick a cap across the meter to ensure no nasty inductive effects of the coil play havoc with the rectifier and driving circuit if anything close to pure current drive is used.
You should only really be putting electrolytic (>1uF) values in series if there is significant overshoot. I personally prefer a slow response with no overshoot at all, but we are getting into personal preference here, as opposed to looking objectively at the VU standard
...Maybe you are used to slower meters? The non-standard meters can be very slow sometimes. Experiment with the parallel cap and find the smallest value that gives no overshoot.
Mike
I've used some "meters" for some friends who likes some gadgets, in some of my amplifiers (almost all times salvaged from old equipment). For simplicity I forget the ballistics scheme and simply adjusted an resistor value to correct reading at amp saturation in full scale.
Even so, I prefer Ge diodes because these people love to see VU's in operation, even at low volumes. At low volumes using Si diodes the VU don't move. With Ge diodes the VU have some movement, obviously due to lower forward voltage.
And even ignoring ballistics, a slow VU is always an slow VU, and a fast VU is always faster ths the mecanichally slow VU independently of driving, in my findings.
Since I only need to read peaks I always use a cap in parallel, big enough to flat response and small enough to not slowing it (a compromise value).
Even so, I prefer Ge diodes because these people love to see VU's in operation, even at low volumes. At low volumes using Si diodes the VU don't move. With Ge diodes the VU have some movement, obviously due to lower forward voltage.
And even ignoring ballistics, a slow VU is always an slow VU, and a fast VU is always faster ths the mecanichally slow VU independently of driving, in my findings.
Since I only need to read peaks I always use a cap in parallel, big enough to flat response and small enough to not slowing it (a compromise value).
You can use silicon diodes to achieve a better sensitivity than a conventional Germanium diode topology using the improved drive circuit listed in my article.
The big cap in parallel doesn't turn a VU meter into a peak meter unless the capacitor is driven with a VERY low impedance (far less than a conventional line output) and even then it is only a quasi peak meter.
The big cap in parallel doesn't turn a VU meter into a peak meter unless the capacitor is driven with a VERY low impedance (far less than a conventional line output) and even then it is only a quasi peak meter.
No, the meters will need to follow the music, at least with some of my friends. They hate the fake, slow or delayed (or following uncertain thing) moving meters from some el-cheapo audio systems (like some Philips micro-systems from early 2000) and even the el-cheapo rectifier make all the difference here...
But for some people I know you idea is very interesting...
They are not my "audiophile" friends, of course... for audiophiles is warranted refinements like these VU driver.
PS.: in my personal system I don't have VU and even EQ
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Voltmeter-1-analog
Another interesting VU driver (similar method but implemented in discrete form).
About using Ge, guys like me love to use obsolete technology (not in critical applications, of course), but since some people will not want or don't have access to old parts...
Another interesting VU driver (similar method but implemented in discrete form).
About using Ge, guys like me love to use obsolete technology (not in critical applications, of course), but since some people will not want or don't have access to old parts...
Yes, I clarified my usage in post 32 to not incenticate people to use this in line-level sources. My wording is generally confuse...
Ah, if tube aficionados plug the el-cheapo diode VU in their preamp, disaster is warranted...
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Due to my newbie non-native English wording, for a moment ago we are comparing apples to oranges (signal level vs power amplifiers).
For helping newcomers in VU land to not become confused, I will remark:
...my "normal" application for simple Ge rectified meters are in the output of power amplifiers. Here the levels are high, have plenty of current and generally have low driving impedance, and unless the "customer" are audiophile or amp has a low DF, the simple "Ge" meter cover the application in most amps and in this particular case the Ge option will have less components, hence my choice. But here Ge helps a little with low signals.
The thread proposition is reccomended for all remaining applications (precision readings, line level, low DF amps, audiophile, etc).
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