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efinque View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote efinque Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 12:33am
Originally posted by JonB67 JonB67 wrote:

No, i didn't.  I asked a specific question about using measuring voltage to set limiters, which if you had read it you would know.

A limiter is a compressor with a ratio of 10:1 or more (I've heard audio engineers fight over this constantly)

You have an incoming signal of 5V which the limiter, set to 3V threshold will attenuate it to 3.2V because the voltage exceeding the threshold is 2V, and output is 2V/10 = 0,2 so that's 1,8V attenuation.

So the output from a 5V signal would be 3V + 0.2V = 3,2V.

But it's only in theory. In practice with program material (not many people listen to 5VDC) you'd get all sorts of stuff like upward compression, PSU ripple voltages, fluctuations etc.. analog compressors with MOSFETs/JFETs or tubes will surely add all kinds of flavours to the signal, and the built-in ones in amps are usually fixed, fire-and-forget types.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dylan-penguinmedia Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 12:51am
Originally posted by efinque efinque wrote:

Originally posted by JonB67 JonB67 wrote:

have you googled fluke?

I've used a Fluke IR thermometer to take readings from freezers.

The only analog multimeter I found online by a quick search was by Axiomet, and it was around 70e. A normal DMM costs about 20e (I had a Velleman earlier, now I have a Uni-T)

Jesus... put the keyboard down and have a word with yourself.

There’s good and expensive, as well as cheap and less good multimeters in both analogue and digital flavours. ‘A normal DMM costs 20e’ is another of your bollocks comments which means nothing to anyone. 

This is the problem with the internet. Someone crops up and says something with enough conviction, it becomes ‘fact’.
Someone else will read your comments and think it’s correct. Not just on about this post, but a few I’ve seen you comment on.

If you don’t know, say so. There are people that DO know, leave the answering to them.

/lesson


Edited by dylan-penguinmedia - 29 December 2018 at 12:52am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote concept-10 Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 6:38am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Elliot Thompson Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 8:18am
Originally posted by JonB67 JonB67 wrote:

Originally posted by Elliot Thompson Elliot Thompson wrote:

Originally posted by JonB67 JonB67 wrote:

Im wondering why people calculate their limiter settings.  

Im not particularly electronics or amp savvy. (Guess i wouldn't need to ask if i was)

Why can't you just unplug the speakers and measure the voltage with the amp set to 11 and dial the limiters down until its acceptable?

Its clearly not this simple as i can't find anyone suggesting this. What am i missing? 

The only thing that was not mentioned by the previous comments is... What exactly are you protecting? 

The majority of modern day amplifiers offer an on board limiter to prevent severe clipping. Most sound man use stand alone limiters to protect their loudspeakers from receiving too much power providing, the on board limiter in the amplifier is not adjustable. 

So are you protecting your loudspeakers from too much power or, are you using an amplifier that does not include an on board limiter in which, you need to use a stand alone limiter to prevent the amplifier from clipping?


Best Regards,  


Now that's a useful question. 

I've got a matrix 6004 which will give some useful clip protection,  and two numark dimension 4s which probably won't. I have a dcx and Im not  investing in new kit but want to make sure I'm making the most protection from what i already have. 

Primarily looking to not burn out my drivers by feeding them  more than they can handle.




Since you are aiming for loudspeaker protection, each amplifier should be limited differently according to the loudspeaker it is driving. Your Behringer DCX is more than enough to get the job done.

 

Your biggest challenge will be converting the output volts from the amplifier into watts to reflect the rating of your loudspeakers under their nominal load.

 

 

High frequency drivers are always an easy load to an amplifier whereas, mid to low frequency drivers can/will put a heavier load on the amplifier at times.  So even though you could get away calibrating the amplifiers with no load, you will need to limit the voltage possibly 2 – 3 volts more than the outcome to prevent any fluctuations of the loudspeaker load.

 

Your Fluke meter is all you need and some means of noise (White or Pink) as noise reflects more to wards dynamic music material than sine waves. If you have difficulty converting the wattage (Program Power) of your speakers into volts at the nominal load, post the numbers here as I designed such a calculator to execute such a fete when I bench test amplifiers.

 

 

 

Best Regards,

Elliot Thompson
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Father-Francis Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 9:06am
Originally posted by efinque efinque wrote:

Originally posted by JonB67 JonB67 wrote:

No, i didn't.  I asked a specific question about using measuring voltage to set limiters, which if you had read it you would know.

A limiter is a compressor with a ratio of 10:1 or more (I've heard audio engineers fight over this constantly)

You have an incoming signal of 5V which the limiter, set to 3V threshold will attenuate it to 3.2V because the voltage exceeding the threshold is 2V, and output is 2V/10 = 0,2 so that's 1,8V attenuation.

So the output from a 5V signal would be 3V + 0.2V = 3,2V.

But it's only in theory. In practice with program material (not many people listen to 5VDC) you'd get all sorts of stuff like upward compression, PSU ripple voltages, fluctuations etc.. analog compressors with MOSFETs/JFETs or tubes will surely add all kinds of flavours to the signal, and the built-in ones in amps are usually fixed, fire-and-forget types.
Quarantining is good for you , it’s gets you asking more than answering 🙀🤐

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Post Options Post Options   Thanks (0) Thanks(0)   Quote JonB67 Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 10:07am
Originally posted by efinque efinque wrote:

Originally posted by JonB67 JonB67 wrote:

No, i didn't.  I asked a specific question about using measuring voltage to set limiters, which if you had read it you would know.

A limiter is a compressor with a ratio of 10:1 or more (I've heard audio engineers fight over this constantly)

You have an incoming signal of 5V which the limiter, set to 3V threshold will attenuate it to 3.2V because the voltage exceeding the threshold is 2V, and output is 2V/10 = 0,2 so that's 1,8V attenuation.

So the output from a 5V signal would be 3V + 0.2V = 3,2V.

But it's only in theory. In practice with program material (not many people listen to 5VDC) you'd get all sorts of stuff like upward compression, PSU ripple voltages, fluctuations etc.. analog compressors with MOSFETs/JFETs or tubes will surely add all kinds of flavours to the signal, and the built-in ones in amps are usually fixed, fire-and-forget types.

Again, you make a statement as fact and back it up with spurious anecdote to make it sound valid. (The bit in brackets)

Then you give me something which isn't about using a multimeter to set limiters, but about how much a limiter might attenuate, which if im setting from a measurement at the speaker end, matters not. Would only matter what the end reading was.  

Then you end with the usual fluff and meaningless nonsense we associate with your posts.  

None of it was helpful. Im sure you mean well but this has to stop.  It  confuses, dilutes and derails threads,  and people post because they need help not a bs diatribe based on whimsy and assumption about a vaguely associated thing.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote JonB67 Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 10:10am
What i was hoping for it my guess was right, was to come up with a thread people can use as reference so they can grab their multimeter once the driver is warmed up, knock up as patch lead (if they want,  i think it makes sense) they can plug in between the cable and the cab, set limiters to max, read the voltage and reduce the limiter until its reading what they need.  

 If its viable it seems a simple solution compared to the reams and reams and hundreds of confused posts on this forum and others on calculating it. 

Im sure this method has issues, but if it works its got to be easier!

I'll have a play and post my results. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Elliot Thompson Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 12:15pm

How precise the limiting needs to be reflects the person at the controls.

 

Most of the time everything needs to be calculated for the person at the controls can be very heavy handed on the faders. So brick wall limiting is the only solution. This is very important when renting out your kit and, those who are experiencing their first sound system.

 

Those that are more conscientious on not over driving their system and fall within the single user realm can be easy going applying limiters. A little clipping once in a while won’t lead to having their loudspeakers reconed as they tend to reduce the gains instantly when clipping occurs.

 

Then there are very small group of individuals as myself that use no limiters whatsoever and devise other means of voltage restrictions to regulate the output. This usually stems from literally monitoring everything at all times in addition to having certain components distort (upstream) giving one the impression the system is operating at full tilt (down stream) when it is not if/when required.   

 

Some users are not content until they hear heavy distortion. Some users are aiming for the cleanest sound as possible and would sacrifice volume for very low distortion. And there are others that have tons of headroom at their disposal and use the extra power for momentary peaks.

 

Best Regards,

Elliot Thompson
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Danielr Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 2:25pm
Originally posted by Elliot Thompson Elliot Thompson wrote:

..components distort (upstream) giving one the impression the system is operating at full tilt (down stream) when it is not if/when required.   

Some users are not content until they hear heavy distortion.

:D love this.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Conanski Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 5:07pm
Originally posted by JonB67 JonB67 wrote:

What i was hoping for it my guess was right, was to come up with a thread people can use as reference so they can grab their multimeter once the driver is warmed up, knock up as patch lead (if they want,  i think it makes sense) they can plug in between the cable and the cab, set limiters to max, read the voltage and reduce the limiter until its reading what they need.  

 If its viable it seems a simple solution compared to the reams and reams and hundreds of confused posts on this forum and others on calculating it. 

Im sure this method has issues, but if it works its got to be easier!


The big issue with your method is it's only really applicable to low frequency drivers that can handle the full output of the amp. What if you're powering a 100w compression driver with a 350w or 500w amp, then you can't just let it blast away while you dick with measurements you need to have a limiter setting in place that is at least in the right ballpark before the driver is ever attached. Like it or not there will always be some math involved.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Earplug Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 6:36pm
Originally posted by JonB67 JonB67 wrote:

Originally posted by Elliot Thompson Elliot Thompson wrote:

Originally posted by JonB67 JonB67 wrote:

Im wondering why people calculate their limiter settings.  

Im not particularly electronics or amp savvy. (Guess i wouldn't need to ask if i was)

Why can't you just unplug the speakers and measure the voltage with the amp set to 11 and dial the limiters down until its acceptable?

Its clearly not this simple as i can't find anyone suggesting this. What am i missing? 

The only thing that was not mentioned by the previous comments is... What exactly are you protecting? 

The majority of modern day amplifiers offer an on board limiter to prevent severe clipping. Most sound man use stand alone limiters to protect their loudspeakers from receiving too much power providing, the on board limiter in the amplifier is not adjustable. 

So are you protecting your loudspeakers from too much power or, are you using an amplifier that does not include an on board limiter in which, you need to use a stand alone limiter to prevent the amplifier from clipping?


Best Regards,  


Now that's a useful question. 

I've got a matrix 6004 which will give some useful clip protection,  and two numark dimension 4s which probably won't. I have a dcx and Im not  investing in new kit but want to make sure I'm making the most protection from what i already have. 

Primarily looking to not burn out my drivers by feeding them  more than they can handle.




And - of course, the follow up question should be what drivers do you have? And loaded into what? And what kind of material will it be playing?

It will all influence how you need to set up the system, ie for live music, with more dynamics, you can 'loosen up' on the limiting, whereas playing highly compressed muzak, you need to be a bit more conservative, ie limit earlier in order to make sure that the average power to your speakers doesn´t pass the thermal limits, etc.


And for multimeter advice, look no further:

https://www.youtube.com/watch?v=gh1n_ELmpFI

LOL LOL LOL




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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dub Specialist Sound Quote  Post ReplyReply Direct Link To This Post Posted: 29 December 2018 at 7:33pm
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