Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
Fons Adriaensen wrote: On Sun, Aug 23, 2009 at 07:27:18PM +0100, Dan Mills wrote: Lets say your card is aligned so that 0dbFS = +18dbu (EBU standard), then 0Vu = +4dbu = - 14dbFS, so a software VU calibrated for 0Vu = -14dbFs should read the same as an external Vu calibrated for +4dbu = 0Vu. If it does not then either a calibration setting is off somewhere or one of the meters is faulty. True. But even a definition such as 'dB FS' is ambiguous, and it's easy to make mistakes as a result of that. Consider a sine wave that is just below digital clipping. This would be called '0 dB FS', but the actual RMS level is 3 db lower. I've seen at least one context where this same signal would be called -3dB FS. Which somehow makes sense as well. AFAIK the first interpretation is the more common one. 'Peak level' vs 'intrinsic level': * 'dbFS' refers to 'peak level', 'full-scale square wave' * 'dbFS RMS' refers to 'intrinsic level, 'full-scale sine wave'. This is how is in Germany distinguished and because of the words on English, it might be an international way to distinguish it. actually fairly common with professional cards. And it avoids a lot of problems. Semi-pro cards will not have the correct levels, but some can be quite consistent between channels. For example my Terratec EWS88MT has less than +/- 0.1 dB variation between its 8 channels, both for input and output. But the actual level is just +3.5dBu for a FS sine wave. The real misery starts when (as reported in a recent post on LAU or LAD), a user finds four volume controls between his audio file and the physical output (plus of course a fifth one on his amplifier), and then of course gets confused on how to set all of them. I guess this is the leading point. Even professional IO amps at times need calibration. We should imagine a setup like 'sound card -- tube pre-amps -- mastering recorder'. For this scenario a VU meter needs to be an external one. Ralf ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
[LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Everyone, There is an updated version of the Invada LV2 plugins available. This release contains a new plugin, 'Meters', which features Peak, VU, Phase Spectrograph meters. Screenshot is here: http://www.invadarecords.com/images/downloads/Screenshot-Invada_Meters.png The amount of headroom between 0dB on the VU to digital 0dB is selectable from - -15dB to -3 dB. There is no right value for this, it really depends on the music, so just pick whatever value that causes the VU to spend most of it's time between +/- 3dB. (this stems from the fact that 0dB in the analogue world is the optimal level whereas 0dB in the digital world is the maximum level) Other Notable Changes: * Envelope attack decay for meters now consistent across sample rates. * Improved font selection and sizing for widgets. * Initialised uninitialised variables in the delay plugin (thx Damon). * Added LV2 'Portgroups' extension to RDF's (thx Dave). * 'DESTDIR' make option to help packagers (thx Philipp). * Various GUI tweaks. Download from here: http://www.invadarecords.com/Downloads.php?ID=0264 Ubuntu packages from here: https://launchpad.net/~invada/+archive/ppa Post bugs here: https://bugs.launchpad.net/invada-studio Send comments here :) Also packagers for distros may be interested on the 'nopkg' version of the tarball that contains no debian folder: https://launchpad.net/invada-studio/lv2/1.2 Final note: Please be aware that the 'External UI' extension the plugins use is due for a revision to make in fully compliant with LV2 spec V3 and above. When this occurs there shouldn't be any issues as I'll provide version of the GUI's compatible with both revisions. regards, Fraser -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFKkQSLNZroiEh4erwRAqM/AKDZ3+UWGtZuncD7URuAbuS/s1jpdgCfZQRW p7Pf1XIBpdgBIzhcIveu5ZM= =GHHe -END PGP SIGNATURE- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Fons Fons Adriaensen wrote: What's the point of using a meter if you adjust it to the signal ? You are not changing the signal, you are changing the amount of headroom the VU meter has. http://www.reference.com/browse/wiki/Headroom To put it simply, 0dB on analogue equipment is indicating the optimal level. There is an amount of headroom above that level before distortion will occur. In the digital domain 0dB is the absolute maximum level and distortion occurs at this point.. So whenever analogue equipment needs to work with digital equipment it is configured so that 0dB in the analogue domain is at some (hopefully calibrated and consistent) level below 0dB in the digital domain. The actual value is arbitrary and depends part on preference and part on the quality of your analogue gear. So if you elect to have 9dB of headroom on you analogue gear, then you'd select -9dB on the plugin, and then VU metering 0dB will have the peak metering -9dB. - -18 to -9 is common, but I've seen all sorts of things. Anyway the meter plugin freezes my machine if the signal is muted or removed. Probably due to denormals. I can't reproduce that. A clue may help. (distro, arch, kernel, soundcard, host etc). The plugins have been built on ubuntu studio (hardy) x64 and tested on ubuntu jaunty (x64), Arch linux (x64) AV linux (x32). The VU is not a VU, Correct since this plugin isn't in the analogue domain. It's a simulant. It does convey the 'perceived volume' of a signal better than a peak meter and does help if you are mixing to tape. the spectrum doesn't use valid 1/3 octave filters by any standard, please advise where this standard is. AFAIK there are just algorithms that simulate the behaviour of electronic RC circuits with varying degrees of success, and yes I have a munge. Sorry if it disturbs you. and the phase meter doesn't indicate anything useful. Apart from the relative phase difference between the left and right channels. With the demise of vinyl the importance of phase has been lost too to some extent so it doesn't surprise me you don't what this meter is for or what it's trying to tell you. On vinyl out of phase signals make the needle go up and down instead of side to side, this makes the needle bounce out of the groove. Worse still is what happens when you have low frequency out of phase sounds. The wave length (on the vinyl) is large enough for the cutter to go through the vinyl... = This is why everything below 200Hz is mono'd for vinyl during mastering in case you were wondering. A quick guide to interpreting the phase meter: * A mix that never goes +/- 20 is too mono. Pan something. Create some space with reverb. etc * A mix that spends all it's time between +/- 45 is as 'wide' as you want to get. You should able to see some variety in there of course, ie a verse and a chorus should be different widths. * If the phase meter spends any time over +/- 55 then audible cancellation will occur if the mix is mono'd or listened to from a distance. * Any travel over +/- 60 is trouble, there is something out of phase in the mix. although this may sound great with your head between the speakers it's going to suck when heard anywhere else. * If the meters stays at +/- 90 then the whole mix is out of phase :) regards, Fraser -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFKkWJ9NZroiEh4erwRAopXAKCd7WvN5FZLUw4upP9dpQb0K8SpjwCeOVAh KkDpklpsKFIKijiJAEV1PWo= =U2Yr -END PGP SIGNATURE- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Mon, Aug 24, 2009 at 01:38:37AM +1000, Fraser wrote: Hi! So whenever analogue equipment needs to work with digital equipment it is configured so that 0dB in the analogue domain is at some (hopefully calibrated and consistent) level below 0dB in the digital domain. The actual value is Just a note: I personally don't like VUs in the digital domain. I prefer Bob Katz' K metering system (K12, K14, K20) with well defined headrooms. Check out this page for a detailed description on the K metering system: http://www.digido.com/level-practices-part-2-includes-the-k-system.html Note that many commercial software vendors ship analyzer plugins using the K system, i.e. RME's DigiCheck. I'd suggest to go for this, too. Just my $0.02 -- mail: a...@thur.de http://adi.thur.de PGP/GPG: key via keyserver ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Sun, 2009-08-23 at 18:57 +1000, Fraser wrote: The amount of headroom between 0dB on the VU to digital 0dB is selectable from - -15dB to -3 dB. There is no right value for this, it really depends on the music, so just pick whatever value that causes the VU to spend most of it's time between +/- 3dB. (this stems from the fact that 0dB in the analogue world is the optimal level whereas 0dB in the digital world is the maximum level) You may want to increase the range of that reference level calibration, particularly as it applies to anything having a semi peak reading response. -16dbFS = +4dbu is not an uncommon place to run, and -20 is another common alignment. Regards, Dan. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
VU meter: Maybe you should call it 'analogVUemu'. Phase correlator: Yep, some people generally spilt frequencies at around 200, resp. 250 Hz before they add effects or they avoid to panorama deep sounds. A phase correlator can be mistaken, because of some single sounds that don't matter in the sum. I just check my mixes by listening to them in mono, but I agree that some people don't hear phases and they become trouble, because their tapes are forbidden to be played on the air. I didn't test your plugins and I don't believe in meters and phase correlators. I guess your VU meter is useless, but the phase correlator seems to be useful, the way both are described by you. Explanation: - Bad! Having a VU meter that can be adjusted to allegedly be in sync with some analogue VU meter never ever will be fine. Compare margin for your digital meters and the meters on your mixing console by playing the same song several times, they always will differ a little bit different, each time you play the song. It seems to be dangerous to have such a VU meter, similar to microphones with switches at the handle, a stupid idea that can cause a lot of trouble. - Okay! Broadcasting laws force to stick to limits for phase correlation and referring to your description it will be possible to see it by your phase meter. My 2 cents to the theory of your meters. Cheers, Ralf Fraser wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Fons Fons Adriaensen wrote: What's the point of using a meter if you adjust it to the signal ? You are not changing the signal, you are changing the amount of headroom the VU meter has. http://www.reference.com/browse/wiki/Headroom To put it simply, 0dB on analogue equipment is indicating the optimal level. There is an amount of headroom above that level before distortion will occur. In the digital domain 0dB is the absolute maximum level and distortion occurs at this point.. So whenever analogue equipment needs to work with digital equipment it is configured so that 0dB in the analogue domain is at some (hopefully calibrated and consistent) level below 0dB in the digital domain. The actual value is arbitrary and depends part on preference and part on the quality of your analogue gear. So if you elect to have 9dB of headroom on you analogue gear, then you'd select -9dB on the plugin, and then VU metering 0dB will have the peak metering -9dB. - -18 to -9 is common, but I've seen all sorts of things. Anyway the meter plugin freezes my machine if the signal is muted or removed. Probably due to denormals. I can't reproduce that. A clue may help. (distro, arch, kernel, soundcard, host etc). The plugins have been built on ubuntu studio (hardy) x64 and tested on ubuntu jaunty (x64), Arch linux (x64) AV linux (x32). The VU is not a VU, Correct since this plugin isn't in the analogue domain. It's a simulant. It does convey the 'perceived volume' of a signal better than a peak meter and does help if you are mixing to tape. the spectrum doesn't use valid 1/3 octave filters by any standard, please advise where this standard is. AFAIK there are just algorithms that simulate the behaviour of electronic RC circuits with varying degrees of success, and yes I have a munge. Sorry if it disturbs you. and the phase meter doesn't indicate anything useful. Apart from the relative phase difference between the left and right channels. With the demise of vinyl the importance of phase has been lost too to some extent so it doesn't surprise me you don't what this meter is for or what it's trying to tell you. On vinyl out of phase signals make the needle go up and down instead of side to side, this makes the needle bounce out of the groove. Worse still is what happens when you have low frequency out of phase sounds. The wave length (on the vinyl) is large enough for the cutter to go through the vinyl... = This is why everything below 200Hz is mono'd for vinyl during mastering in case you were wondering. A quick guide to interpreting the phase meter: * A mix that never goes +/- 20 is too mono. Pan something. Create some space with reverb. etc * A mix that spends all it's time between +/- 45 is as 'wide' as you want to get. You should able to see some variety in there of course, ie a verse and a chorus should be different widths. * If the phase meter spends any time over +/- 55 then audible cancellation will occur if the mix is mono'd or listened to from a distance. * Any travel over +/- 60 is trouble, there is something out of phase in the mix. although this may sound great with your head between the speakers it's going to suck when heard anywhere else. * If the meters stays at +/- 90 then the whole mix is out of phase :) regards, Fraser -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Sun, Aug 23, 2009 at 06:02:46PM +0200, Adrian Knoth wrote: I prefer Bob Katz' K metering system (K12, K14, K20) with well defined headrooms. Get jkmeter, also includes a real correlation meter. For VU and PPM meters that actually behave as VU and PPM meters, get jmeters. Both available on http://www.kokkinizita.net/linuxaudio/downloads Ciao, -- FA Io lo dico sempre: l'Italia è troppo stretta e lunga. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Sun, 2009-08-23 at 18:26 +0200, Ralf Mardorf wrote: - Bad! Having a VU meter that can be adjusted to allegedly be in sync with some analogue VU meter never ever will be fine. Compare margin for your digital meters and the meters on your mixing console by playing the same song several times, they always will differ a little bit different, each time you play the song. Of course they read different things! They are measuring different things! The VU is a slow response meter (300ms integration time IIRC)intended to (badly) track perceived volume, the meters on (most) DAWs are closer to digital peak meters intended to monitor absolute peak levels. Both are useful and both have a place. The differences each time you play are why we leave the thick end of 20db of headroom between 0 VU and 0dbFS, you should (in a production environment) never be going anywhere near 0dbFS (there is no need for it in the age of 20+ bit ADC noise floors). It seems to be dangerous to have such a VU meter. Why is it dangerous? it tells you something about RMS levels which you would not otherwise know (peak reading meters provide little guidance as to perceived volume). Now, I don't know about this particular implementation (I don't have an LV2 host to hand), but a good implementation of a VU would not be an inherently bad thing to have available. Regards, Dan. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Mon, Aug 24, 2009 at 01:38:37AM +1000, Fraser wrote: What's the point of using a meter if you adjust it to the signal ? You are not changing the signal, you are changing the amount of headroom the VU meter has. http://www.reference.com/browse/wiki/Headroom Yes, I know that. Still same question: what's the point of using a meter if you adjust it to the signal rather than adjusting the signal until the meter says it's OK ? Of course a slow meter must be calibrated to show 0 well below full scale digital. But that should be fixed. Anyway the meter plugin freezes my machine if the signal is muted or removed. Probably due to denormals. I can't reproduce that. A clue may help. (distro, arch, kernel, soundcard, host etc). I added some simple code to avoid denormals in the bandpass filter and in the 'envelope' calculation, and that removes the problem (just adding a small DC offset, 1e-20). The VU is not a VU, Correct since this plugin isn't in the analogue domain. So what ? If you call it VU and it looks like one, it should behave as a VU and have VU ballistics. This one surely doesn't. the spectrum doesn't use valid 1/3 octave filters by any standard, please advise where this standard is. For example IEC61260, or the BS/EN with the same number. and the phase meter doesn't indicate anything useful. Apart from the relative phase difference between the left and right channels. It measures an average of atan ((l-r)/(l+r))), which maybe related to phase for a sine wave with equal amplitude in both channels, but there it ends. Panning a sine wave L to R produces all values between 0 and 45. If it measures phase that should be 0. Anyway phase is not the thing to measure, correlation is. And this is certainly not a correlation meter, just compare it with a real one. Ciao, -- FA Io lo dico sempre: l'Italia è troppo stretta e lunga. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Adrian, Adrian Knoth wrote: Just a note: I personally don't like VUs in the digital domain. agree, their primary purpose is a bit meaningless. I prefer Bob Katz' K metering system (K12, K14, K20) with well defined headrooms. Check out this page for a detailed description on the K metering system: http://www.digido.com/level-practices-part-2-includes-the-k-system.html Note that many commercial software vendors ship analyzer plugins using the K system, i.e. RME's DigiCheck. I'd suggest to go for this, too. thanks for the link, I wasn't aware of that before. I'll have a look at implementing it. cheers, Fraser -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFKkXfQNZroiEh4erwRAlmvAKCtO1fJyCsLIL8gHwtFiY4ukK0E7ACg3cAa QtRxyD5wjABhBMZOCUdUeuI= =YRQA -END PGP SIGNATURE- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Dan, Dan Mills wrote: You may want to increase the range of that reference level calibration, particularly as it applies to anything having a semi peak reading response. -16dbFS = +4dbu is not an uncommon place to run, and -20 is another common alignment. H, I can see where this is going, I might be better off letting people dial in any value rather than giving them a few to choose from? somewhere someone could be using anything... cheers, Fraser -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFKkXiSNZroiEh4erwRAj8XAJ4zcr7JGzgggQpJjWamgTmTNA5nowCgg9dY 2y1eNH6vqDy5GyMPOeMuGY0= =NWIb -END PGP SIGNATURE- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Ralf, Ralf Mardorf wrote: VU meter: Maybe you should call it 'analogVUemu'. I'm thinking 'tascam analogue level meter', perhaps everyone will chill a bit then :) F. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFKkXncNZroiEh4erwRArePAJ4lF3/YJh2zd1XtZuF8QLyT/TIpWACgwjTH 7icBLkTuUOU3zI7v3HHDsGw= =vGxD -END PGP SIGNATURE- ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
Fraser wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Adrian, Adrian Knoth wrote: Just a note: I personally don't like VUs in the digital domain. agree, their primary purpose is a bit meaningless. I prefer Bob Katz' K metering system (K12, K14, K20) with well defined headrooms. Check out this page for a detailed description on the K metering system: http://www.digido.com/level-practices-part-2-includes-the-k-system.html Note that many commercial software vendors ship analyzer plugins using the K system, i.e. RME's DigiCheck. I'd suggest to go for this, too. thanks for the link, I wasn't aware of that before. I'll have a look at implementing it. cheers, Fraser This are recording techniques. You shouldn't apply them by any function to adjust the meter to any imaginary point. The only useful thing is to have a pre-adjusted meter, that can't be readjusted by the audio engineer. For people who like Katz's technique, some marks might be useful and/ or a function that shows the most low and the most loud level. There might be other rules of thumb, not only Katze's. Meters are used to adjust signals. I understand what you aim at, I also understand what switches on mics, to turn them on and of are designed to, but there are good reasons why such things shouldn't be done. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Sun, Aug 23, 2009 at 05:44:55PM +0100, Dan Mills wrote: The VU is a slow response meter (300ms integration time IIRC)intended to (badly) track perceived volume, The VU specs are based on what was possible 50 or more years ago. A typical VU would just be a diode bridge and a series resistor feeding a moving coil meter, and no active electronics (you had to drive them using a separate line amplifier to avoid distortion caused by the diode bridge). That means it measures the average of the absolute value (and not RMS), and the dynamics are defined by a second order filter acting on the rectified value. For a sine signal corresponding to 0 VU the meter should reach 99% in 300ms, and overshoot by between 1 and 1.5% before returning to the correct value. The differences each time you play are why we leave the thick end of 20db of headroom between 0 VU and 0dbFS, you should (in a production environment) never be going anywhere near 0dbFS (there is no need for it in the age of 20+ bit ADC noise floors). VUs are not very useful today. On one side, the digital domain does not overload as gracefully as magnetic tape, so you should be conservative and use e.g. -20dB digital = 0 VU. On the other hand some of today's commercial music is so heavily compressed that a VU calibrated like that and used on a final mix would go off scale well before there is any digital overload. In that case you'd want a different calibration, even less than the historical one which was around 9 dB below 'peak', with peak being a somewhat softer limit than it is today. So if you still want to use a real VU it almost has to have variable calibration, which is a bad idea as it doesn't allow you to form any stable mental picture of the relation between loudness and the meter indication. Combining a true RMS and a digital peak meter in one display without any gain difference between the two is IMHO the best way to go, and it is exactly what e.g. the K-meter does. Ciao, -- FA Io lo dico sempre: l'Italia è troppo stretta e lunga. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
TU Berlin: Lediglich bei den Rundfunkanstalten besteht wegen des Austauschs von Programmmaterial auch über die Landesgrenzen hinweg die Notwendigkeit von einheitlichen Richtlinien. Da- bei gilt in Europa ein Übernahmepegel von +18 dBu für 0 dBFS (EBU R68), in den USA +24 dBu (SMPTE RP155). On English, for international broadcasting you need different adjustments. But then it's important that the meter is informed about the analogue mixer of the sound card too ;). I guess it will become nearly impossible to fit a dBFS RMS meter to any VU meter outside the studio in the box. An external VU meter can't be replaced by one in the box for Linux using different sound cards. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
hollun...@gmx.at writes: The meter doesn't show up in lv2rack. It shows up in ardour2. zynjacku and lv2rack have cache of suitable plugins. Did you rescan the LV2 world after you installed the new version of Invada plugins? -- Nedko Arnaudov GnuPG KeyID: DE1716B0 pgp69OfHrJ8Ys.pgp Description: PGP signature ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
Dan Mills wrote: The key is that every stage has to have a known calibration, which is actually fairly common with professional cards. Okay :) I don't know professional cards for home recording myself and the professional studios I know have external VU meters. For my Envy24 based sound card I guess the converters aren't accurate, but even with this I might be wrong. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Re: [LAD] [ANN] Invada Studio LV2 Plugins 1.2.0
On Sun, Aug 23, 2009 at 07:27:18PM +0100, Dan Mills wrote: Lets say your card is aligned so that 0dbFS = +18dbu (EBU standard), then 0Vu = +4dbu = - 14dbFS, so a software VU calibrated for 0Vu = -14dbFs should read the same as an external Vu calibrated for +4dbu = 0Vu. If it does not then either a calibration setting is off somewhere or one of the meters is faulty. True. But even a definition such as 'dB FS' is ambiguous, and it's easy to make mistakes as a result of that. Consider a sine wave that is just below digital clipping. This would be called '0 dB FS', but the actual RMS level is 3 db lower. I've seen at least one context where this same signal would be called -3dB FS. Which somehow makes sense as well. AFAIK the first interpretation is the more common one. actually fairly common with professional cards. And it avoids a lot of problems. Semi-pro cards will not have the correct levels, but some can be quite consistent between channels. For example my Terratec EWS88MT has less than +/- 0.1 dB variation between its 8 channels, both for input and output. But the actual level is just +3.5dBu for a FS sine wave. The real misery starts when (as reported in a recent post on LAU or LAD), a user finds four volume controls between his audio file and the physical output (plus of course a fifth one on his amplifier), and then of course gets confused on how to set all of them. Ciao, -- FA Io lo dico sempre: l'Italia è troppo stretta e lunga. ___ Linux-audio-dev mailing list Linux-audio-dev@lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
