hello,
i have a few projects on the go and am wanting to add in some kind of limiter in case someone tries to run a to stronger signal through the amps inputs.
i'm using some 2nd hand old low wattage speakers so want to be able to prevent someone accidentally destroying them. im guessing it should go between the pre and power stages after any patch in the power section?
can any one please help with advice and or schematics that would work well for this. preferably some thing with an adjustable trim pot so it can be dialed in for the maximum safe speaker output for a start then replaced with a fixed resistor.
If any one can offer suggestions if this is the right way to go about doing this.i have seen a few schematics on the net though i think they are for hifi maybe and i am not good at calculating formulas to get the correct values.
also only have a few speakers to use and cant afford to get higher rated ones to match the amp atm. thanks
i have a few projects on the go and am wanting to add in some kind of limiter in case someone tries to run a to stronger signal through the amps inputs.
i'm using some 2nd hand old low wattage speakers so want to be able to prevent someone accidentally destroying them. im guessing it should go between the pre and power stages after any patch in the power section?
can any one please help with advice and or schematics that would work well for this. preferably some thing with an adjustable trim pot so it can be dialed in for the maximum safe speaker output for a start then replaced with a fixed resistor.
If any one can offer suggestions if this is the right way to go about doing this.i have seen a few schematics on the net though i think they are for hifi maybe and i am not good at calculating formulas to get the correct values.
also only have a few speakers to use and cant afford to get higher rated ones to match the amp atm. thanks
If you employ an MC3340 before the amplifier stage, control the attenuator with a rectified AC loudspeaker voltage. The higher the voltage the higher the attenuation. Just preset the knee point.
This is the correct way to control and limit the power output to your speakers and the way professional limiters work.
http://uploads.cq-dx.ru/pdf/MC12-MC99/MC3340RE.PDF
https://www.google.co.uk/search?q=m...ei=Av1gWNz9C8P4aqm0lpAD#imgrc=O0y0YMBAwUePKM:
This is the correct way to control and limit the power output to your speakers and the way professional limiters work.
http://uploads.cq-dx.ru/pdf/MC12-MC99/MC3340RE.PDF
https://www.google.co.uk/search?q=m...ei=Av1gWNz9C8P4aqm0lpAD#imgrc=O0y0YMBAwUePKM:
i have found this simple circuit with values included. i'm not sure about the 3340 because i wanted to try get away from running the signal through an ic..... and because im not really sure of the connections, could you please look at the mc3340 picture i edited and see if i am on the right track and am looking at the right schematic? thanks
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i thought about maybe using an led VU meter ic on the pre and a simple LDR to send the signal to ground when it gets to a set voltage but im worried the LDR may introduce to much noise when it activates? not sure if any one uses this method
on the MC3340 would i run a full wave bridge rectifier from the speaker + to pin 2 via VR1?
also would i need to add more capacitance to ground after the rectifier or is C2 there to do that? thanks
also would i need to add more capacitance to ground after the rectifier or is C2 there to do that? thanks
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That MC3340 sure has a LOT of distortion (1%) associated with it!! Perhaps a better approach would be to use an opto-isolator (Excelitas VTL5C4), as Rod Elliott does in his "Complete Powered P.A." project.
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