hello friends
as I wrote above my amp is 3000W@8 ohm, and my speaker is 500W@8 ohm. How to limit power ?!
The audio processor i use has no peak limit. There is only an rms limit. How to measure and limit the amplifier so it doesn't overload out the speaker...
I have an idea that I don't know if it's a good one. To measure the lowest impedance in the area in which the speaker will work and to calculate how many volts in the output of the amplifier I should have for 500 watts.
I have smaart and clio , can i use some of them ?
as I wrote above my amp is 3000W@8 ohm, and my speaker is 500W@8 ohm. How to limit power ?!
The audio processor i use has no peak limit. There is only an rms limit. How to measure and limit the amplifier so it doesn't overload out the speaker...
I have an idea that I don't know if it's a good one. To measure the lowest impedance in the area in which the speaker will work and to calculate how many volts in the output of the amplifier I should have for 500 watts.
I have smaart and clio , can i use some of them ?
just how much SPL is needed?
and with no knowledge of speaker efficiency that becomes a very convoluted question to answer.
if your clipping a 3000 watt amp and it's not loud enough there something wrong....
and with no knowledge of speaker efficiency that becomes a very convoluted question to answer.
if your clipping a 3000 watt amp and it's not loud enough there something wrong....
I once made an input (soft) limiter with LED's and some resistors.
You need to measure the gain of the amp.
Calculate the max rms voltage you want +/- 60volts for 500w/8ohm
divide by the gain ( lets say 40) so you need to limit your input voltage to 60/40 = 1.5 volt rms 2.1 peak.
So use two anti-parallel green LEDs and use a 200 series resistor (2x100 if symmetric).
Is this a bridged amplifier? Can you it Single Ended against ground? Then you have the other one as spare.
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Job #1 is to know the conditions for those specs. Peak @1 kHz, 10% THD, one channel driven is entirely different from RMS @20 Hz - 20 kHz, 0.01% THD, both channels driven. The same for the speakers, Peak vs. RMS, long term vs. short term...
We also need the input sensitivity and impedance of the amp. Then we can propose some sort of soft clipper that will operate at the right signal level. mvs0's circuit above will work but introduce a lot of distortion even at levels well below the start of clipping. An active circuit will work much better.
We also need the input sensitivity and impedance of the amp. Then we can propose some sort of soft clipper that will operate at the right signal level. mvs0's circuit above will work but introduce a lot of distortion even at levels well below the start of clipping. An active circuit will work much better.
I have carefully measured the circuit, it has low distortion 3db before peak clipping level, I will check if I find back my measurements. Peak power , one or two channels , impedance does not matter as this amp will never reach anywhere it's max spec.
Even in simulation, which is always overoptimistic, I get a lot of distortion with this type of arrangement... Can you show the schematic of your circuit? The power spec conditions do matter to establish or at least ballpark the actual output power of the amplifier. Unless the clipper is buffered, the input impedance is required to adjust properly the voltage divider of which the clipper is part.
Grmbggh, 3000w @8 ohm calls for 155VRMS and 27. 5 Amp peaks if speaker would be flat resistor, which it's not.
To get that PS must be + and - 220 V DC, and that if output is rail to rail...
I'm really really interested to see circuit diagram of this.
Otherwise, if this is right spec, you can always reduce mains input V by some autotransformer or buckling transformer. Reducing input power V will reduce PS rails V and make amp live much longer, unless PS is regulated which I hardly believe at this power
To get that PS must be + and - 220 V DC, and that if output is rail to rail...
I'm really really interested to see circuit diagram of this.
Otherwise, if this is right spec, you can always reduce mains input V by some autotransformer or buckling transformer. Reducing input power V will reduce PS rails V and make amp live much longer, unless PS is regulated which I hardly believe at this power
Most instruments like voltmeters and likely your audio processor do not actually measure true RMS but simply assume 71% of the peak voltage. So, an "RMS" limiter should be just fine. A real RMS limiter would actually be better because it would corelate to the heat in the speaker voice coil.
And it is dangerous to use a calculated value of doubtful wattage values. If you provided model numbers of your equipment, perhaps we could verify the power ratings.
And it is dangerous to use a calculated value of doubtful wattage values. If you provided model numbers of your equipment, perhaps we could verify the power ratings.
the schematic:
The circuit is driven from the XLR out of a Marantz AV10 (75 ohm output impedance?)
Output is going to the XLR in of a Quad Artera Mono amp. (10k input impedance)
I will see if I can do the measurements again today..
a 2cent passing thought >
Speakers can handle transient peaks of higher W than continuous power. A lot of music by its nature is transient, with bass usually representing
higher power levels and a more sustained time-nature.
If your speaker has a reasonably flat impedance, there is actually a VERY SIMPLE way to 'power protect' and provide single band compression in one.
* If you pick the right wattage 'filament globe' and run it in series with your speaker, it will provide audio compression and 'soak up' excess power.
At low to moderate power levels, it will be essentially inaudible. As high power starts, it will start to glow and increase in resistance providing protection.
Such a method is actually most effective at low frequencies where you find high energy/power levels. Believe it or not, the compression is very 'musical'.
As a somewhat useful byproduct, when acting, it also reduces the load on the amplifier making things to run cooler 🙂
https://thelightingoutlet.com.au/pr...500w-halogen-r7s-globe-warm-white-3k-dimmable
PS.
American 110V globes are far more useful for the purpose than 220/240V globes.
Speakers can handle transient peaks of higher W than continuous power. A lot of music by its nature is transient, with bass usually representing
higher power levels and a more sustained time-nature.
If your speaker has a reasonably flat impedance, there is actually a VERY SIMPLE way to 'power protect' and provide single band compression in one.
* If you pick the right wattage 'filament globe' and run it in series with your speaker, it will provide audio compression and 'soak up' excess power.
At low to moderate power levels, it will be essentially inaudible. As high power starts, it will start to glow and increase in resistance providing protection.
Such a method is actually most effective at low frequencies where you find high energy/power levels. Believe it or not, the compression is very 'musical'.
As a somewhat useful byproduct, when acting, it also reduces the load on the amplifier making things to run cooler 🙂
https://thelightingoutlet.com.au/pr...500w-halogen-r7s-globe-warm-white-3k-dimmable
PS.
American 110V globes are far more useful for the purpose than 220/240V globes.
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@desislavov
Does a trained DJ hear when the drivers / boxes begin to compress and distort and just controls by the ear what the speakers can stand?
Or is it a protection for people using your equipment?
What about some lightbulbs in series well dimensioned and compressing visibly the excessive watts?
Usual trick for tweeter protection.
Maybe useful for whole boxes if well designed from the wattage.
Does a trained DJ hear when the drivers / boxes begin to compress and distort and just controls by the ear what the speakers can stand?
Or is it a protection for people using your equipment?
What about some lightbulbs in series well dimensioned and compressing visibly the excessive watts?
Usual trick for tweeter protection.
Maybe useful for whole boxes if well designed from the wattage.
Nice idea, but most of the speakers are far from flat especially at the resonance frequency
Do keep in mind that at 'higher ohm resonant frequency' the power is automatically reduced to start with.
If the impedance went up from 8ohms to 16ohms, the power 'consumed' would be half > a bit like a 'head start' regarding power-handling.
If the impedance went up from 8ohms to 16ohms, the power 'consumed' would be half > a bit like a 'head start' regarding power-handling.
the measurements:
Done with the (ancient) E-MU 0404, XLR in/out
Note: the soft clipper has an insertion loss of 8dB, the input of the E-MU clipped at -10dB in the loopback measurement.
This is to illustrate that a passive soft clipper with LED's can have low distortion.