Here's the signal status display.
For reasons beyond me, Broadgun software refuses to do its regular thing and shrinks whatever. Still legible, though.
Response time for any (beside the power on, which optional) to react to signal changes is around 7 mS.
I usually put the ciruit on the amp board(s), not as a separate standalone PCB. However, as a separate PCB, it is fully functional as an add-on board to existing amps. If anyone is keen, I can. with much digging, find that versioncurrently off the PC.
For reasons beyond me, Broadgun software refuses to do its regular thing and shrinks whatever. Still legible, though.
Response time for any (beside the power on, which optional) to react to signal changes is around 7 mS.
I usually put the ciruit on the amp board(s), not as a separate standalone PCB. However, as a separate PCB, it is fully functional as an add-on board to existing amps. If anyone is keen, I can. with much digging, find that versioncurrently off the PC.
It is usable with any power input voltage of up to +60V (that's as far as I tried it).
As shown, using R7 and R10, it worked for 0 dB = 28.5V. Clipping LED lit at Vout= 32.5V because as I said, it does not show true clipping, rather that you are in dire straits and clipping may occur at any moment. I feel that if the clipping is already happening, you will probably heart it happening and won't need a LED to tell what you are already aware of.
@Kindhornman
I took it that your two way speaker will be biamped internally. If so, you will need two such circuits, one for each amp, to truly make sense, although if they do not produce the same power levels, this allows you readjust the values as you please.
As shown, using R7 and R10, it worked for 0 dB = 28.5V. Clipping LED lit at Vout= 32.5V because as I said, it does not show true clipping, rather that you are in dire straits and clipping may occur at any moment. I feel that if the clipping is already happening, you will probably heart it happening and won't need a LED to tell what you are already aware of.
@Kindhornman
I took it that your two way speaker will be biamped internally. If so, you will need two such circuits, one for each amp, to truly make sense, although if they do not produce the same power levels, this allows you readjust the values as you please.
Strictly, rms only has meaning for periodic waveforms. Which real music isn't. All else is some form of time averaging, but it's taken implicitly to mean 'that which has the same equivalent level as sine rms, dBu style. Or would read the same on ye olde dBu meter. Yer pays yer money and takes yer choice though.......
Yes, but time averaging over the length of a symphonic movement isn't meaningful here. What I mean is transients within a few seconds or tens of seconds involving louder passages - both the average level and transients within it need to be reproducible accurately by the playback system at realistic concert levels.
It's Mahler, he would have scored everything for brass given half a chance, even within loud passages there will be instantaneous massive transient SPLs. Natural brass instruments are fiercely loud, let alone when you're 30 ft away from a dozen of them at full tilt !
Yes 0dBFS is a hard limit, so programme material average or rms level as read by a Vu meter ought to be -12dB or so, if not there is already some compression or limiter built into the mastering of the recording, which there very often is BTW..........otherwise people would whine that they can't hear it in the car chiz chiz chiz.......
I can't hear my bruckner 9 on BIS in the car, even with the annoying speed controlled loudness function on (which I turned off)
At some point I need to hook up the Umik and see in my room what I get. Given its 10'x11' and I sit 6 feet from the speakers I am unsure I would want to try and replicate a concert hall volume in there.
But my gut feel is that for most of the music I listen to the average is lower than -12dB.
Ah well mahler 9 watching the VU plugin
At some point I need to hook up the Umik and see in my room what I get. Given its 10'x11' and I sit 6 feet from the speakers I am unsure I would want to try and replicate a concert hall volume in there.
But my gut feel is that for most of the music I listen to the average is lower than -12dB.
Ah well mahler 9 watching the VU plugin
This Mahler 9 by sir mark elder and the Halle is rather good. Product Details . Very dynamic. Scott would hate it 
. VU meter on Foobar (of unknown accuracy) rarely goes above -20 and no where near -12 but comparing peak meter (also of unknown accuracy) with VU I think I can see what you were getting at in that -12dBVU effectively means peak is FS.
Other than getting a feeling for level off the old ratshack sound meter not really sure VU has any real relevance in this modern computer audio world.
. VU meter on Foobar (of unknown accuracy) rarely goes above -20 and no where near -12 but comparing peak meter (also of unknown accuracy) with VU I think I can see what you were getting at in that -12dBVU effectively means peak is FS. Other than getting a feeling for level off the old ratshack sound meter not really sure VU has any real relevance in this modern computer audio world.
Don't you had seen the movie: "Spinal Tap" ?discovered that those old things could go beyond 11 and all the way up to TWELVE!!!
https://www.youtube.com/watch?v=KOO5S4vxi0o
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My volume control don't have any number. I presume it is because my 98dB/W enclosures and my 150W amp can deliver >120dB, witch is near infinity ?
(Never tried that loud)
In doing live symphonic concert work, headroom of 30 dB to me is transparent. 20 dB occasionally shows the ugly tail of clipping. 10 dB is fine for bus stations.
Every musician will tell you a forte is always a forte. My meter says it is 10 dB louder in a performance than at a rehearsal.
As most folks only play recorded music 20 dB headroom is probably all you get.
Currently popular music contract riders often call for 110 dBa at the mix position. But for that 10 dB of headroom is more than enough.
Every musician will tell you a forte is always a forte. My meter says it is 10 dB louder in a performance than at a rehearsal.
As most folks only play recorded music 20 dB headroom is probably all you get.
Currently popular music contract riders often call for 110 dBa at the mix position. But for that 10 dB of headroom is more than enough.
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Interestingly the Mahler was recorded both live and in rehersal. So far unable to locate any interviews with the engineer or producer to see what they actually did. and how the matched levels given a live FFF is very F as you say!
Edit: That was nice. The last couple of minutes of the 4th movement were under -55dbVU the whole way. I must listen to that again at home and see how that works in the domestic environment.
Edit: That was nice. The last couple of minutes of the 4th movement were under -55dbVU the whole way. I must listen to that again at home and see how that works in the domestic environment.
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Do they mean continuous or "Max"? Given that in the EU there are now max limits on headphones how have concert promoters avoided having similar limits?
Does that explain why so many pop concerts have a peak around 3 KHz?
RMS has meaning for non-periodic stuff as well. Heating power may be the best way to understand it. Noise needs to be qualified by bandwidth and crest factor. The EU standard for measuring sensitivity for headphones uses a specific crest factor to emulate music of around 2 which is probably valid for pop music.
They use a standard sound level meter set to "A" weighting. They expect this level without compression, but clipping is fine. (limiters!)
Pop concert peak is due to equalization and air losses.
Ed,
Do they also specify the distance from the stage for the mix console? That would surely change the measurements you are going to get depending on how far from the stage and the stack or hanging array you are. I stopped going to live shows of Rock and Roll, so many times the distortion levels and sound levels just made the show un-enjoyable.
Do they also specify the distance from the stage for the mix console? That would surely change the measurements you are going to get depending on how far from the stage and the stack or hanging array you are. I stopped going to live shows of Rock and Roll, so many times the distortion levels and sound levels just made the show un-enjoyable.
No! The old number was 102 dba @ 100' now it is wherever the mix position is located.
I was referring to the consequence of long term listening at those levels.
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So, if I only tell only tell you peak level within noise of unknown variance and sample time you will tell me its rms level...........and vica versa ?
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