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EV MTL 4 question.

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Al Rettich:
Have a pair of original MTL 4ís. 800w into 4ohms.  Thought I had a pair of amps that put out 800w into 4 ohms, but I donít.  What I do have is a pair of Crown XTi 6002ís.  2100w into 4 ohms. I know I can turn down the volume, but trying to remember the voltage so I can set the limiter at 800w.  Can someone help a guy out?

Scott Holtzman:

--- Quote from: Al Rettich on December 21, 2023, 08:36:03 PM ---Have a pair of original MTL 4ís. 800w into 4ohms.  Thought I had a pair of amps that put out 800w into 4 ohms, but I donít.  What I do have is a pair of Crown XTi 6002ís.  2100w into 4 ohms. I know I can turn down the volume, but trying to remember the voltage so I can set the limiter at 800w.  Can someone help a guy out?

--- End quote ---


The simple answer is 56.6 voltage=current*resistance


It's ohms law.  Learn the formula and you can always answer these questions.


The problem with the simple answer is it will not get the most out of your speaker.  You have to consider the crest factor of your music and the speakers ability to handle transients.  Then you can set a voltage limiter.  Do the XTi's have a voltage limiter?


Much of this comes from having experience and blowing a few drivers along the way.  A good education isn't cheap.


Are you interested in 4 fully loaded and refurbed subs to go with them?







Mike Caldwell:
While your programming the amp set a high pass at 40hz Butterworth at least 24db for those.
The 800 watt rating was RMS so EV called it a 1600 watt program rating.

You could bump it up to 1200 watts and be safe / 70 volts.

Art Welter:

--- Quote from: Mike Caldwell on December 22, 2023, 09:00:47 AM ---While your programming the amp set a high pass at 40hz Butterworth at least 24db for those.
The 800 watt rating was RMS so EV called it a 1600 watt program rating.

You could bump it up to 1200 watts and be safe / 70 volts.

--- End quote ---
Mike,

The MTL4 is two "800 watt" four ohm loads, 1600 watts EIA RS426A, 6400 watts peak for for 10 milliseconds.
Fb (box tuning) is 37Hz, the minimum impedance at Fb is 3.45 ohms, 52.5 volts for 800 watts.

A BW24dB at 35 Hz would be safe, but over 52.5 volts for long term limiting could char those drivers.
The EV test signal using -3dB points at 100Hz and 1200Hz allowed 105 volts peak (3200watts)

45-50 volts RMS long term (a couple seconds..) & 70volts (1420 watts) as a peak limit should be a good start to keeping the drivers intact, if the horizontal pair have not already sagged too far ;^).

Art

Ivan Beaver:

--- Quote from: Al Rettich on December 21, 2023, 08:36:03 PM ---Have a pair of original MTL 4ís. 800w into 4ohms.  Thought I had a pair of amps that put out 800w into 4 ohms, but I donít.  What I do have is a pair of Crown XTi 6002ís.  2100w into 4 ohms. I know I can turn down the volume, but trying to remember the voltage so I can set the limiter at 800w.  Can someone help a guy out?

--- End quote ---
This is another audio myth.

"Turning down the gain reduces the power output of the amp".  WRONG

Unless you exceed the voltage rails of the input stage, you can turn the amp down to "1" and it will still be able to deliver full power to the loudspeaker.  It will just take a larger input signal to do so.

Limiters can be tricky to set up, depending on how many and what type you have to work with.

They are also like air bags in a car.  they can help protect against certain things, but driving it over a cliff don't expect them to protect you.  Responsible operation is the best protection.

If you don't have responsible operation, then BE SURE to set the limiters LOWER than what might be "normal".

For a single stage limiter, I suggest setting it between 1/4 continuous (not program) power (half voltage) or at the continuous rating.

It depends on the speed of the attack. If it is "automatic", then it is usually tied to the high pass filter time.

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