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Crown XTI 2 limiter

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Hello

how can I discover that out signal is max and limiters are correct out signal?

I need it to control input signal from my mixer

in case whith xti 1, we have red indicate from panel, when limiter correcting out signal

what about xti 2?

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I'm not sure exactly what you mean... You want to know if the signal your mixer is outputting into the XTi is at its max level so you don't push it more or you want to know when is the limiter engaging?

Avi

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Thanks!

How can I now, when limiter starting to engage and limiting xti2 ?

xti1 have clip limiter, xti2 haven't it.

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Excuse me,

I was changed limiter threshold from max to min, volume changed too, but indicators was only in green ...

May be clipping off...?

I have 4 xti6002 with vrx900.

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I'm terribly sorry but I'm having a hard time understanding your questions. Not that I'm comparing but I'm having the same problem with my wife :)

In the XTi2 the limiter settings are dBFs units and threshold and release values in ms so I don't know what those Max and Min values are...

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indicator was not clipping when I changed limiter threshold from MINimum (dBFs=0) to MAXimum (-40) value :)

in which cases limiter clipping?

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In this case the limiter is used to limit the power of the amp, not as an anti clipping device but rather as a speaker protector. The clip indicator is a simple comparator of the signal in the input Vs the signal in the output, for instance you can feed the amp a clipped signal and as long as the clipping is not created in the amp the clip LED is not going to light.

At 0 dBFs there is no limiting done and at 40 dBFs (or -40 to be exact) you're limiting the amp to 1/1000 of its power so for sure the volume will be effected.

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I may be wrong, but on the main panel (as seen in System Architect 3.4) there are two limiter indicator, one for each channel, that lit up 'yellow' when the limiter is 'limiting'. It is not red on my panel. I haven't checked with Band Manager but I feel it should be similar.

To really know if the limiter circuit is functional, you could use a sine wave generator and monitor the output with a multimeter or oscilloscope. Multimeter may read RMS but the scope reads peak 2 peak. You may need to convert from RMS to peak because limiter values are in VDC.

Alain

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I may be wrong, but on the main panel (as seen in System Architect 3.4) there are two limiter indicator, one for each channel, that lit up 'yellow' when the limiter is 'limiting'. It is not red on my panel. I haven't checked with Band Manager but I feel it should be similar.

To really know if the limiter circuit is functional, you could use a sine wave generator and monitor the output with a multimeter or oscilloscope. Multimeter may read RMS but the scope reads peak 2 peak. You may need to convert from RMS to peak because limiter values are in VDC.

Alain

Thanks, this is true

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Ok

For example.

I load preset for my speakers VRX932LA1. Then, I send signal to the input of amps (from the mixer) and calibrate it with output signal (after DSP).

How can I know: DSP limiting signal in the output or not (from the FOH place)? I need to monitor maximum signal in the output.

(Using dbx260 or another DSP, you can control input signal from the mixer and monitor limiting signal in the output by clipping on panel)

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All you need to do is connect the XTi to a laptop with SA, wirelessly or not, and monitor the limiter indicator. There is minimal support for connecting this amp to your computer wirelessly so you'll need to do your own research from previous posts here and on other forums.

Here is a good thread to start:

http://www.crownaudio.com/forums/index.php?showtopic=4392

Let us know how you plan to continue...

Avi

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Could it be that you get confused between clipping and limiting? Make sure you understand exactly what each one of those mean!!!

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All you need to do is connect the XTi to a laptop with SA, wirelessly or not, and monitor the limiter indicator. There is minimal support for connecting this amp to your computer wirelessly so you'll need to do your own research from previous posts here and on other forums.

Here is a good thread to start:

http://www.crownaudi...?showtopic=4392

Let us know how you plan to continue...

Avi

Many thanks!

I find this as the only possible solution

But does not understand the lack of gain redaction of limiter.

Gain reduction is essential to calibrate the system.

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Could it be that you get confused between clipping and limiting? Make sure you understand exactly what each one of those mean!!!

I mean red flash on front panel, when limiter correct signal in the output, but this related only xti1, unfortunately.

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Another note on Clipping indicators: Most amps monitor input AND output for clipping. The limiter circuit can limit (acting like a quick acting compressor) the output signal with minimum distortion; If Clipping is visible while limiter is functionnal, clipping may come from the input circuit! Of course, if the input signal is hot enough and not clipping the input circuit, Clipping may still occur at the output.

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I have not received an answer to my main question, which related with speaker protection.

When the threshold is exceeded by the signal, my speakers get maximum power (for example: dbfs=0) !!!

When did threshold is exceeded by the signal???

What can point to it???

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Limiter indicators in SA and BM: My bad: No such indicators in either app. Only Clip, Ready and thermal indicators.

As for the previous post, could it be that the Clip indicators flash because the input is clipping and not the output?

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I can't find signs when the threshold is exceeded by the signal, in SA and BM !

How can I calibrate PA, after load preset, in this case not understand ... :unsure:

Crown%206002.jpg

1.png

2.png

Can you look at the pictures above and answer, the threshold is exceeded by the signal or not ??? :o

Riddle? ))))))))))))

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I would like to first describe how the limiter works: When the threshold is exceeded on the output side of the amp for a longer time then the attack time, then the limiter engages and limits the amplifiers power to MAX_AMP_POWER-THRESHOLD for as long a time as the exceeded signal continuous, plus the release time.

Now for a real world example: If you need to power and protect a 200W RMS speaker that has 800W peak power, at 8 ohms, you first need to choose an amp that has about enough power output for the speakers peak power rating. For an 800W peak power at 8 ohms the XTi4002, which has 650W at 8 ohms is a pretty good match. Now we need to limit the amps RMS power to about 200W, so the formula for calculating is this:

10 X Log(P1/P2)

If we feed our data we get:

10XLog(200/650)= -5.11 dBfs

That's what you enter the limiter in the amp.

I know it's a bit complicated but that's always the case when you really dig into things :)

Also you need to allow long enough attack and release time to allow this limiter to function as an RMS limiter.

Also you need to remember you only protect the biggest driver in your cab and not all the drivers!!!

In edition to that I sent Eric from the SA forum a question about monitoring of the limiter action.

Avi

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