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#241
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Peak overload
"Roy W. Rising" wrote: Eeyore wrote: Peter Larsen wrote: Arny Krueger wrote: Good point. All a clipping indicator indicates is clipping or at best potential clipping. To put this in perspective, the clipping point for most pro audio gear is in a braod range from maybe +10 to +30 dBu. That's the irrelevant info, the relevant info is whether the indicator has lead and if so, how much and indeed whether its indication is credible. Peak operating levels through a console or a preamp should be at least 10 dB below clipping. Under those conditions, the clipping light is always dark, and unlikely to ever light. I don't get the point in that speculation. If you want maximum signal to noise ratio then you need to use the available dynamic range. Sometimes, for specmanship, the available maximum level is SO high (e.g. +30dBu) it would be nuts to try to use it. There are many Distribution Amplifiers (DAs) with +30dBm (yes, *m*) output capability. It's only dB*m* if there's actually a 600 ohm load connected. I very much doubt that's ever the case. In which case it's assuredly dB*u*, a voltage. I simply can't see the point of dBms today in a non-600ohm world. It strikes me as pointlessly retrogressive. Good systems design requires 18dB headroom throughout the chain. Where did you get your 18dB from ? For +4 dBm environments, that's +22dBm. +22dBu. The kind of op-amps I typically use (4560 4580 5532) will deliver +21dBu when operated on the +/- 17V supplies I favour. Additionally, I often operate the channels at 'reduced level', typically 6dB 'below external level'. That offers (21-4)+6 dB of headroom = 23dB. In the days of +8 dBm systems, +26dBm was needed. +30 dBm happens to be One Watt. It's a tidy number, and not just "specmanship". In what way is it ever practical ? If a piece of equipmet with such a spec is ever operated at these levels it'll usually simply clip the following equipment. We used to describe operators as VU "Meter Minders" or "Pin Pounders". For the latter, some downstream forgiveness saves a gaggle of problems. VUs are worthless things that simply provide minor entertainment IMHO. There have been many discussions about the level at which the "peak" indicator should light. Certainly it should be *before* clipping. No question about that ! Anyone with decent hearing doesn't need a red light to confirm what their ears are telling them. Sadly it seems too many clip light operate 'too late' to be much use. A good suggestion is an amber LED 6dB below clipping, and a red one 3dB below. Good operation would see some occassional ambers and almost never a red. I quite like the traffic light idea. It could be done perhaps with a single bi-colour LED which saves panel space. I tend to set my 'peak' indicators (as I currently call them) at 6dB before actual clip. Graham |
#242
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Peak overload
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#243
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Does anyone have a schematic for a Behringer CX3400
Arny Krueger wrote: "Marc Amsterdam" wrote course i mix by ear, i just dont set the gains by ear. How do you set the gain, when the console has no PFL metering? I doubt Marc ever uses such a thing. Graham |
#244
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Arny Krueger wrote: "Marc Amsterdam" wrote in message Not checking your metering when mixing is like not checking the speedometer when driving, or altitude when flying, NOT a good idea! Agreed - providing of course that there is a PFL meter to check with. NOT agreed here. It's almost never necessary. But then I have been mixing for 35 years. Newbies may feel the need to do it more 'by the book' than is actually necessary. You can tell from a mix if you've got any levels that are whackily out of kilter through simple experience. Graham |
#245
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Does anyone have a schematic for a Behringer CX3400
Arny Krueger wrote: "Phildo" wrote in message "Mr.T" MrT@home wrote in message So you don't understand the difference between "metering" (as you originally stated) and a simple clip "indicator" then. Besides the clip indicators are channel indicators, nothing to do specifically with the PFL bus (as you stated) in any case. No but they are metering Nope, they are warning lights. I guess Phildo this means that you always shift your car by revving it up while waiting for the oil pressure light to come on. It looks like Phildo and George both believe in the 'flickering clip lights' school of level setting. What ninnies they are. It's a recipe for a bad sound. Graham |
#246
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Eeyore wrote:
Arny Krueger wrote: "Marc Amsterdam" wrote in message Not checking your metering when mixing is like not checking the speedometer when driving, or altitude when flying, NOT a good idea! Agreed - providing of course that there is a PFL meter to check with. NOT agreed here. It's almost never necessary. But then I have been mixing for 35 years. Newbies may feel the need to do it more 'by the book' than is actually necessary. So, let me get this straight, you are saying that meters are for newbies? |
#247
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Eeyore wrote:
Marc Amsterdam wrote: Eeyore wrote: Marc Amsterdam wrote: wrote: is the clip light pre or post fade on the 95% of live soud mixig desks? this should be easy, even for you he would not know as he sets it by ear.... Don't YOU mix by ear ? I know I don't mix using the clip lights (or meters for that matter). course i mix by ear, Fine i just dont set the gains by ear. What's the point when you know how loud you want a channel in the mix using your ears ? Would you for example trim a channel according to the meters to get a nice strong signal and then operate the fader at -20 because you don't need to add much of that signal ? Graham That would improper gain staging, and I'm here to tell you that's not the way to do it anyway... |
#248
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Peak overload
Eeyore wrote:
There is always some special case - extremely high supply rail voltage comes to mind - but the general recommendation surely would be to use resistive attenuation so as to get clip levels reasonably aligned. Things that temporarily didn't matter in the "16 bit era" has begun mattering again, ref. the recent thread about the DCX. If the DCX is as noisy as suggested, that's due to indifferent design, not any issue with overload levels. The issue seems to me to be that its dynamic range is referenced to a voltage that is significantly above sensitivy for rated output from poweramps. Seems to be no different from how things would be it if was all analog. The solution is simple: reduce input sensitivity on power amps used with it. Graham Kind regards Peter Larsen |
#249
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Eeyore wrote:
Behringer uses no 'fancy' parts. I can readily get any required spares at low cost. These are generic parts that 'everyone' uses like dual op-amps for example. The hindrance is the absence of a schematic which will likely add an hour or more to the time required to service it. Understood and implied in my suggestion of diy repairs being realistic, thanks anyway. Graham Kind regards Peter Larsen |
#250
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Peak overload
Arny Krueger wrote:
"Peter Larsen" wrote in message Peak operating levels through a console or a preamp should be at least 10 dB below clipping. Under those conditions, the clipping light is always dark, and unlikely to ever light. I don't get the point in that speculation. A new commandment I give unto you: Blessed are they who operate without headroom, for they shall be known as producers of clipped sounds. Arny, you need to check what the criteria for audible clipping are. I got quite similar critique during one of the last recordings I made with my Panasonic DAT with its wonderful orange peak overload display. That because I put the program over the machines display, I was then confronted with the claim that I was "destroying the recording". As for why I didn't worry: I know what Audition can repair and I know what duration clip I can get away with. It was in a recordist club context, and we listen to each others recordings at monthly meets. My contribution that month was a sample of intentionally clipped audio with differing amount of clipping. The material was classical choir. The first 2 dB of clipping was inaudible to all, I just made the demonstration to get people to understand that it is possible to worry too much about technical perfection, so I didn't make any notes, but I think it was around some 4 dB of clipping that it was perceived as audibly deteriorated. What matters is not the amount of clipping, but rather the duration. A couple of milliseconds tends to be inaudible, this based on information provided at some AES event here in Copenhagen. If you want maximum signal to noise ratio then you need to use the available dynamic range. Mixing consoles have from about 90 dB (cheap analog) to 144 dB (24 bit digital) dynamic range. Nonsense, they can not have larger dynamic range than a line amp, but yes, a digital mixer can avoid the noise buildup of an analog mixer. Wbat is is discussed here is however the operation of a conventional analog mixer. And in that context you confirm my point, ie. that every single dB of dynamic range matters. The signals they amplify come from sources that have residual noise in both the acoustical and electrical domains. Rarely does the signal being amplified have more then about 75 dB dynamic range. That means that it is practical to allow from 15 to 69 dB for headroom, without significant reduction of the signal's dynamic range. To do that efficiently you of course need to know what you are doing. Exactly. It is a very common mistake to fail to leave enough headroom, and end up with unintended clipping when artists become a little extra exhuberant, etc. I don't always get it right, nobody ever does, but mostly I do get the enthusiasm allocation right. It is not difficult to get things right if you know your equipment and the implements of noise the musicians use. Also some of the time recklessly clipping things is what makes it all work ... for instance, aapls'rs please forgive my use of only recording based examples, I recorded some avant garde jazzclassical this May. The dynamic range was from playing a solid body unamplified to as loud as a drumkit and the same solid body amplified with a pair of small amps can get. There was also a concert not so grand, not always audible during the concert, but required to be audible in the recording. Guess what: I let that electric guitar clip some 8 dB in the fortissimos and unclipped it so as to not loose its ppppp's. When it is showtime, then it also the time for doing what works. I have recorded this musician previously with another example and therefore I was acutely aware that I ran the risk of running out of low range bits, it was - with a 16 bit recorder - a better choice to record a couple of extra bits. And one would have had to do the very same with an analog tape recorder, with the difference being that extrapolation can not save what it does to peaks. That recording is my reason for looking for something with more tracks and bits currently ... I don't like to have to clip recklessly, but I had not had a clean recording afterwards if I hadn't done just that. Your dynamic range math gives results that differ from my experience with these extreme dynamic range recording events ... vox that runs out of bits sounds plastic when lifted in post, at least 20 dB equipment range is required below the room sound, not just the 6 dB you seem to consider enough. Kind regards Peter Larsen |
#251
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Romeo Rondeau wrote: Eeyore wrote: Arny Krueger wrote: "Marc Amsterdam" wrote in message Not checking your metering when mixing is like not checking the speedometer when driving, or altitude when flying, NOT a good idea! Agreed - providing of course that there is a PFL meter to check with. NOT agreed here. It's almost never necessary. But then I have been mixing for 35 years. Newbies may feel the need to do it more 'by the book' than is actually necessary. So, let me get this straight, you are saying that meters are for newbies? No. Don't misrepresent what I said. Keeping an eye on the output levels is important. It's a simple fact however that a well-designed mixer with a sensible internal gain stucture simply can't be clipped if you're operating it competently and not for example using absurd fader settings. Graham |
#252
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Romeo Rondeau wrote: Eeyore wrote: Marc Amsterdam wrote: Eeyore wrote: Marc Amsterdam wrote: wrote: is the clip light pre or post fade on the 95% of live soud mixig desks? this should be easy, even for you he would not know as he sets it by ear.... Don't YOU mix by ear ? I know I don't mix using the clip lights (or meters for that matter). course i mix by ear, Fine i just dont set the gains by ear. What's the point when you know how loud you want a channel in the mix using your ears ? Would you for example trim a channel according to the meters to get a nice strong signal and then operate the fader at -20 because you don't need to add much of that signal ? That would improper gain staging, Would what ? Would be an example of ? Yes I agree. and I'm here to tell you that's not the way to do it anyway... Having a fader at -20 is not a sensible condition in an active mix. I know. Avoid stupid settings like that and the mixer won't clip anyway almost regardless of what you do with it. It's no different essentially from driving a car. You wouldn't attempt 100 mph in 2nd gear either. Graham |
#253
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Peak overload
Peter Larsen wrote: Eeyore wrote: There is always some special case - extremely high supply rail voltage comes to mind - but the general recommendation surely would be to use resistive attenuation so as to get clip levels reasonably aligned. Things that temporarily didn't matter in the "16 bit era" has begun mattering again, ref. the recent thread about the DCX. If the DCX is as noisy as suggested, that's due to indifferent design, not any issue with overload levels. The issue seems to me to be that its dynamic range is referenced to a voltage that is significantly above sensitivy for rated output from poweramps. Seems to be no different from how things would be it if was all analog. The solution is simple: reduce input sensitivity on power amps used with it. You mean operate at it an 'elevated level' ? That requires a higher mix level driving it too. Graham |
#254
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Peak overload
"Peter Larsen" wrote in message
Eeyore wrote: There is always some special case - extremely high supply rail voltage comes to mind - but the general recommendation surely would be to use resistive attenuation so as to get clip levels reasonably aligned. Things that temporarily didn't matter in the "16 bit era" has begun mattering again, ref. the recent thread about the DCX. If the DCX is as noisy as suggested, that's due to indifferent design, not any issue with overload levels. Used right, the DCX is not an noisy box. The issue seems to me to be that its dynamic range is referenced to a voltage that is significantly above sensitivy for rated output from poweramps. Seems to be no different from how things would be it if was all analog. The solution is simple: reduce input sensitivity on power amps used with it. Easy enough to do since most pro audio amps have input level controls. |
#255
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Peak overload
"Peter Larsen" wrote in message
Arny Krueger wrote: "Peter Larsen" wrote in message Peak operating levels through a console or a preamp should be at least 10 dB below clipping. Under those conditions, the clipping light is always dark, and unlikely to ever light. I don't get the point in that speculation. A new commandment I give unto you: Blessed are they who operate without headroom, for they shall be known as producers of clipped sounds. Arny, you need to check what the criteria for audible clipping are. Been there, done that. It has a lot to do with the length of time that the recording is clipped. I got quite similar critique during one of the last recordings I made with my Panasonic DAT with its wonderful orange peak overload display. That because I put the program over the machines display, I was then confronted with the claim that I was "destroying the recording". Yes, the ear has some sonic tolerance for clipping. But most agree that the best clipping is no clipping. As for why I didn't worry: I know what Audition can repair and I know what duration clip I can get away with. It was in a recordist club context, and we listen to each others recordings at monthly meets. My contribution that month was a sample of intentionally clipped audio with differing amount of clipping. The material was classical choir. The first 2 dB of clipping was inaudible to all, I just made the demonstration to get people to understand that it is possible to worry too much about technical perfection, so I didn't make any notes, but I think it was around some 4 dB of clipping that it was perceived as audibly deteriorated. What matters is not the amount of clipping, but rather the duration. A couple of milliseconds tends to be inaudible, this based on information provided at some AES event here in Copenhagen. The ear's tolerance for clipping can probably be inferred from the well-known information about temporal masking. If you want maximum signal to noise ratio then you need to use the available dynamic range. Mixing consoles have from about 90 dB (cheap analog) to 144 dB (24 bit digital) dynamic range. Nonsense, Easy to demonstrate. they can not have larger dynamic range than a line amp, As Graham points out, a simple line amp made up of a cheap op amp might have 110 dB dynamic range. If you bothered to read carefully, my 144 dB number comes from the digital domain. but yes, a digital mixer can avoid the noise buildup of an analog mixer. So it seems with my 02R96. Wbat is is discussed here is however the operation of a conventional analog mixer. Now, we're back to the 90 dB number. And in that context you confirm my point, ie. that every single dB of dynamic range matters. ????????????? The signals they amplify come from sources that have residual noise in both the acoustical and electrical domains. Rarely does the signal being amplified have more then about 75 dB dynamic range. That means that it is practical to allow from 15 to 69 dB for headroom, without significant reduction of the signal's dynamic range. To do that efficiently you of course need to know what you are doing. Exactly. It is a very common mistake to fail to leave enough headroom, and end up with unintended clipping when artists become a little extra exhuberant, etc. I don't always get it right, nobody ever does, but mostly I do get the enthusiasm allocation right. My standard allocation is about 10 dB. It is not difficult to get things right if you know your equipment and the implements of noise the musicians use. ...and your musicians are predictable. Also some of the time recklessly clipping things is what makes it all work ... for instance, aapls'rs please forgive my use of only recording based examples, I recorded some avant garde jazzclassical this May. OK. The dynamic range was from playing a solid body unamplified to as loud as a drumkit and the same solid body amplified with a pair of small amps can get. There was also a concert not so grand, not always audible during the concert, but required to be audible in the recording. Guess what: I let that electric guitar clip some 8 dB in the fortissimos and unclipped it so as to not loose its ppppp's. When it is showtime, then it also the time for doing what works. I have recorded this musician previously with another example and therefore I was acutely aware that I ran the risk of running out of low range bits, it was - with a 16 bit recorder - a better choice to record a couple of extra bits. And one would have had to do the very same with an analog tape recorder, with the difference being that extrapolation can not save what it does to peaks. That recording is my reason for looking for something with more tracks and bits currently ... I don't like to have to clip recklessly, but I had not had a clean recording afterwards if I hadn't done just that. Your dynamic range math gives results that differ from my experience with these extreme dynamic range recording events ... vox that runs out of bits sounds plastic when lifted in post, at least 20 dB equipment range is required below the room sound, not just the 6 dB you seem to consider enough. Where did I say 6 dB? |
#256
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Peak overload
"Eeyore" wrote in message
... There are many Distribution Amplifiers (DAs) with +30dBm (yes, *m*) output capability. It's only dB*m* if there's actually a 600 ohm load connected. I very much doubt that's ever the case. In which case it's assuredly dB*u*, a voltage. I simply can't see the point of dBms today in a non-600ohm world. It strikes me as pointlessly retrogressive. It's not entirely a non-600ohm world. Two places where 600ohm drive is needed: 1) Compressors of the 1176 variety. They're still popular (because they sound good) and show up in a lot of studios. They have 600 ohm input impedance. 2) Telephone lines. If you do any work in the broadcast world, sooner or later you'll need to feed a phone line. Yeah, I know, but sometimes you just plain have to, so you need gear which will do it. Good systems design requires 18dB headroom throughout the chain. Where did you get your 18dB from ? There have been several studies of required peak-to-average capability published, mostly in JAES, and they tend to converge on needing 17-18dB of headroom over "nominal" level (defined as "what you measure on the VU meter"). +22dBu. The kind of op-amps I typically use (4560 4580 5532) will deliver +21dBu when operated on the +/- 17V supplies I favour. Additionally, I often operate the channels at 'reduced level', typically 6dB 'below external level'. That offers (21-4)+6 dB of headroom = 23dB. Which should be fine. These days a lot of balanced outputs are made with opamps driving each leg; if the opamp can deliver +18dBu on each leg (which should be no sweat, even with 15V supplies) then the total will be +24dBu, which means you should never have clipping problems. We used to describe operators as VU "Meter Minders" or "Pin Pounders". For the latter, some downstream forgiveness saves a gaggle of problems. VUs are worthless things that simply provide minor entertainment IMHO. A common view in the UK, not so much here. Having worked with recorders possessing only peak-reading meters, I discovered the hard way how much closer a VU is to matching perceived loudness. Not as close as a Dorrough, perhaps, but a lot closer than the peak meters. Again, in a broadcast environment, where we were scattering insert edits through the tape, on deadline. Peace, Paul |
#257
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Peak overload
Paul Stamler wrote: "Eeyore" wrote There are many Distribution Amplifiers (DAs) with +30dBm (yes, *m*) output capability. It's only dB*m* if there's actually a 600 ohm load connected. I very much doubt that's ever the case. In which case it's assuredly dB*u*, a voltage. I simply can't see the point of dBms today in a non-600ohm world. It strikes me as pointlessly retrogressive. It's not entirely a non-600ohm world. Two places where 600ohm drive is needed: 1) Compressors of the 1176 variety. They're still popular (because they sound good) and show up in a lot of studios. They have 600 ohm input impedance. Where's the 600 ohms ? It has a standard bridging input. http://www.gyraf.dk/gy_pd/1176/1176sch.gif 2) Telephone lines. If you do any work in the broadcast world, sooner or later you'll need to feed a phone line. Yeah, I know, but sometimes you just plain have to, so you need gear which will do it. That's hardly what we're taking about here. But in any case most pro-audio kit WILL drive 600 ohms anyway. It's just not relevant to its everyday use. Good systems design requires 18dB headroom throughout the chain. Where did you get your 18dB from ? There have been several studies of required peak-to-average capability published, mostly in JAES, and they tend to converge on needing 17-18dB of headroom over "nominal" level (defined as "what you measure on the VU meter"). +22dBu. The kind of op-amps I typically use (4560 4580 5532) will deliver +21dBu when operated on the +/- 17V supplies I favour. Additionally, I often operate the channels at 'reduced level', typically 6dB 'below external level'. That offers (21-4)+6 dB of headroom = 23dB. Which should be fine. It is. These days a lot of balanced outputs are made with opamps driving each leg; if the opamp can deliver +18dBu on each leg (which should be no sweat, even with 15V supplies) then the total will be +24dBu, which means you should never have clipping problems. Actually, that configuration in itself doesn't help eliminate clipping since the extra 6dB is gained by the doubling of voltage in the output stage. Think about it. It's the way it lets you run the previous circuitry 6dB lower (as I mentioned above) that helps. We used to describe operators as VU "Meter Minders" or "Pin Pounders". For the latter, some downstream forgiveness saves a gaggle of problems. VUs are worthless things that simply provide minor entertainment IMHO. A common view in the UK, not so much here. So it seems. Having worked with recorders possessing only peak-reading meters, I discovered the hard way how much closer a VU is to matching perceived loudness. Loudness is irrelevant to clipping. To prevent clipping you need only to know the PEAK level and a VU is worthless for that. I imagine this is why so much US audio is heavily clipped. Graham |
#258
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Peak overload
The solution is simple: reduce input sensitivity on power amps used with it. as one would do as the last step of gain stageing ay system that is set the gain to deliver the needed volume at the delivered signal level george |
#259
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Peak overload
"Peter Larsen" wrote in message ... Peak operating levels through a console or a preamp should be at least 10 dB below clipping. Under those conditions, the clipping light is always dark, and unlikely to ever light. I don't get the point in that speculation. If you want maximum signal to noise ratio then you need to use the available dynamic range. To do that efficiently you of course need to know what you are doing. Yes, like not adding high levels of distortion just to gain a couple of dB of S/N ratio. MrT. |
#260
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Peak overload
"Eeyore" wrote in message ... Sometimes, for specmanship, the available maximum level is SO high (e.g. +30dBu) it would be nuts to try to use it. Or even impossible without overloading downstream equipment. MrT. |
#261
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Peak overload
"Eeyore" wrote in message ... If the DCX is as noisy as suggested, It isn't. MrT. |
#262
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Peak overload
"Peter Larsen" wrote in message ... The solution is simple: reduce input sensitivity on power amps used with it. Yep, I'm always amazed how many people always run the power amps at full gain without having a clue about the input levels. MrT. |
#263
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Peak overload
Arny Krueger wrote:
Your dynamic range math gives results that differ from my experience with these extreme dynamic range recording events ... vox that runs out of bits sounds plastic when lifted in post, at least 20 dB equipment range is required below the room sound, not just the 6 dB you seem to consider enough. Where did I say 6 dB? He : The signals they amplify come from sources that : have residual noise in both the acoustical and electrical domains. : Rarely does the signal being amplified have more then about 75 dB : dynamic range. That means that it is practical to allow from 15 : to 69 dB for headroom, without significant reduction of the : signal's dynamic range. 69 from 75 equals 6. You could have written clearer btw. Also, not quoted for clarity, you assert that the dynamic range of a digital mixer can be larger than the dynamic range of the analog stage that feeds signal to the AD converter and you assert that an analog mixers overall dynamic range of 90 dB - rough guideline - allows having a large unused headroom. I disagree, and it seems that it will save a lot of time and effort to agree on disagreeing, we seem to see this differently. An additional reason for disagreeing is that it is my general experience from applying proper gain staging that opamps to my ears tend to sound cleaner (less grainynes when driven hard. Kind regards Peter Larsen |
#264
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Peak overload
wrote in message ... There have been many discussions about the level at which the "peak" indicator should light. Certainly it should be *before* clipping. A good suggestion is an amber LED 6dB below clipping, and a red one 3dB below. Good operation would see some occassional ambers and almost never a red. and most manuals will give you the headroom once the peak blinks so it is a valid way of setting pfl, if others ways are not providied It may be the only way sometimes, but certainly not a satisfactory way. When the clip LED lights, you have no idea whether it is still within the "headroom" allowed, or if it has gone over. Except for the audible distortion of course! :-) MrT. |
#265
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Peak overload
"Eeyore" wrote in message ... and most manuals will give you the headroom once the peak blinks so it is a valid way of setting pfl, if others ways are not providied That results in setting a channel way too HOT. That's the kind of bad advice I recall seeing 30 years ago and it seems IDIOTS like George havn't moved on since then. George is an audio dinosaur if he reckons you should set channel levels so the clip LED blinks. So true, one wonders what the levels on the mix bus are like when he sets 16 channels to clipping point! :-) MrT. |
#266
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Does anyone have a schematic for a Behringer CX3400
wrote in message ... yes arii turn it up till it bliks then turn it back just enough so it doesn't Yep, sometimes the only way, never a good way however. or haven't you ever worked o low end desks where you had to understand how to use the clip meter to set your gain Funny, every Behringer desk I have used has PFL metering. maybe spend some time in the real world of audio The real world of audio often uses mixers with proper metering. I can't say I've ever seen a real studio mixer without a metering bridge! MrT. |
#267
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Eeyore" wrote in message ... Anyone with half a clue can set channel gains without PFL metering. I rarely need to resort to it. Near enough is good enough for you though it would seem. And you probably don't worry about overloading the mix bus either. MrT. |
#268
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
wrote in message ... the FACT ius behriger has a world class repair network ad desires ay repairs of thier products to meet thier standards if you cant abide by that buy something else Fortunately for Behringer not all their customers take that advice! MrT. |
#269
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Eeyore" wrote in message ... The hindrance is the absence of a schematic which will likely add an hour or more to the time required to service it. But you've already spent an hour complaining here! :-) MrT. |
#270
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
wrote in message ... So do you still claim that 95% of professional mixing desks do not have PFL metering? A yes or no will do fine Arnold. Many Yamaha desks do not unfortunately! I guess it depends on who is defining "professional mixing desks" :-) I've got a dozen yamaha desks , from mg's to o1v to the new ls9 they all have pre fade level The EMX series doesn't. which yamahas made in the last 10 years are without even a clip indicator? You consider a single clip LED to be "metering". You must be the only one I imagine. that is a pre fade level indicator and I believe even the emx has them , though I would have to look that up to say with confidence So you don't understand the difference between "metering" (as you originally stated) and a simple clip "indicator" then. Besides the clip indicators are channel indicators, nothing to do specifically with the PFL bus (as you stated) in any case. lets go back , way back, is the clip light pre or post fade on the 95% of live soud mixig desks? Which affects your ORIGINAL statements how exactly? MrT. |
#271
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Marc Amsterdam" wrote in message ... he would not know as he sets it by ear.... No, I'm the one that prefers proper metering. That way I don't have to wait to see the clip LED and hear the distortion, before I know something is wrong. You may prefer the sound of clipping however, my customers usually do not. MrT. |
#272
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
wrote in message ... I am trying to school Mr.T o the very most basic concepts of settig gain structure on live sound desks Thanks, but I'd rather do it right! MrT. |
#273
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Phildo" wrote in message ... How many times do you have to have the reasons for Behringer's decision explained to you before it penetrates your thick skull? I know what their policy is, I DO NOT have to agree with it just because you do. MrT. |
#274
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Eeyore" wrote in message ... The only reason I need a channel PFL is if I need to 'troubleshoot'. Like why the audience has to put up with the distortion :-) Any decent modern mixer with a sensible gain struture (and operated proficiently) is in no danger whatever of clipping a channel under normal mix conditions. As such, fretting over channel levels is a pointless and futile exercise. You are lucky that all the instruments you plug in have similar output levels then. MrT. |
#275
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Phildo" wrote in message So you don't understand the difference between "metering" (as you originally stated) and a simple clip "indicator" then. No but they are metering Thanks for proving my point, you don't know. MrT. |
#276
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Peak overload
Mr.T wrote:
"Peter Larsen" wrote in message ... The solution is simple: reduce input sensitivity on power amps used with it. Yep, I'm always amazed how many people always run the power amps at full gain without having a clue about the input levels. MrT. Power amps always run at full gain, they just have input attenuators |
#277
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Mr.T" MrT@home wrote in message ... "Phildo" wrote in message So you don't understand the difference between "metering" (as you originally stated) and a simple clip "indicator" then. No but they are metering Thanks for proving my point, you don't know. Hi Mr T. I enjoyed your Snickers ad, by the way, which I saw for the first time today. Do you actually have a tank licence? For some reason, this thread found its way to me in a totally non-related newsgroup. Some of your more caustic remarks seem to suggest that you are some sort of authority (without me sounding too sarcastic or getting the regs offside) and coincidentally I'm about to record all of my works. Spooky hey?? Presumably for some home recording by a halfwit (me, not the current posters), I'll learn something here? Rather than ask questions up front, which would defeat the exploration process, I might post an occasional question after I've made a total arse of myself on the HDD recorder thingy that I just bought. While Desert Bob (or whatever manner of creature it was that manifested itself in one of the groups that I inhabit) might be a complete ****wit, ummmm, no, that's all I have to say. -- George "Dude, you don't understand. I.. I'm a Jew. I have a few hangups about killing Jesus!" - Kyle Broflofski - 4 April 2007 |
#278
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
Eeyore wrote:
Romeo Rondeau wrote: Eeyore wrote: Arny Krueger wrote: "Marc Amsterdam" wrote in message Not checking your metering when mixing is like not checking the speedometer when driving, or altitude when flying, NOT a good idea! Agreed - providing of course that there is a PFL meter to check with. NOT agreed here. It's almost never necessary. But then I have been mixing for 35 years. Newbies may feel the need to do it more 'by the book' than is actually necessary. So, let me get this straight, you are saying that meters are for newbies? No. Don't misrepresent what I said. Keeping an eye on the output levels is important. It's a simple fact however that a well-designed mixer with a sensible internal gain stucture simply can't be clipped if you're operating it competently and not for example using absurd fader settings. Graham Fair enough. I see what you mean... |
#279
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Mr.T" MrT@home wrote in message ... "Phildo" wrote in message ... How many times do you have to have the reasons for Behringer's decision explained to you before it penetrates your thick skull? I know what their policy is, I DO NOT have to agree with it just because you do. MrT. we dont care if you agree with it they are satisfying MOST of thier customers and this is how thier policy is established there will always be a few who like to bitch about some no-existent problem and a smart company will just let you walk a dumb compay will go against the vast majoity of thier customers to satisfy a few you are the few if it means that much to you buy something else george |
#280
Posted to alt.audio.pro.live-sound,rec.audio.pro,rec.audio.tech
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Does anyone have a schematic for a Behringer CX3400
"Mr.T" MrT@home wrote in message ... "Phildo" wrote in message So you don't understand the difference between "metering" (as you originally stated) and a simple clip "indicator" then. No but they are metering Thanks for proving my point, you don't know. MrT. your point being what? a clip light is a very rudimetairy meter ad when its all you have it the best you have to work with otoh my ls9 has pages and pages of meters to allow me to see my sigal at miost ay poit I choose from iput to output this is what I perfer but you dont always get that |
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