I have a question about input sensitivity

[Rkrajnov 10+ year member]

I have some Hertz HSK 165s (rated at 150 rms) bridged to a jl 300/4 amp (which is rated at 150 rms 11-14.5v when bridged). First, is that any indication of how high I can turn my input sensitivity or not?

Also, has a high voltage setting which ranges from 8v to 800 mv and a low voltage setting which ranges from 2v to 200 mv. Right now its set about 1/3 of the way to the right on the low voltage setting. When playing songs I tested the alternating volts (set to the 200 on my multimeter) and even playing around the highest I turn the volume ever it wasn't going much over 6 alternating volts at all to the speakers. Speakers were very loud though, didn't hear any distortion or anything but I'm just concerned about blowing them. Theoretically does this mean these speakers should be fine at this level (i.e. that I won't blow them)? I did the math and the according to ohms law they shouldn't go above ~24v so does this mean they're safe where they're at or am I missing something major here?

If I'm wrong in my thinking here, please explain how. I just want to make sure I'm not going to damage my speakers.

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[winkychevelle 10+ year member]

when setting the highs you use a 1000hz tone and unplug the speakers from the amp turn the low voltage knob ifit is using rcas or the high voltage if u are tapped to speaker wires. believe it or not you will prolly only need 40-50w to be loud enough to be enjoyable. just cause u have 150w doesnt mean you have to use it. mose sq competitors will have 250+watt per speaker on tap but very rarely use 25w of that power which is why the distortion in there system is so low. headroom is a good thing. it good to be able to turn ur amps down ,

i say if it gets loud enough without having to turn it up more why turn it up more

 

[Rkrajnov 10+ year member]

when setting the highs you use a 1000hz tone and unplug the speakers from the amp turn the low voltage knob ifit is using rcas or the high voltage if u are tapped to speaker wires. believe it or not you will prolly only need 40-50w to be loud enough to be enjoyable. just cause u have 150w doesnt mean you have to use it. mose sq competitors will have 250+watt per speaker on tap but very rarely use 25w of that power which is why the distortion in there system is so low. headroom is a good thing. it good to be able to turn ur amps down ,
i say if it gets loud enough without having to turn it up more why turn it up more

I see what you mean and ya I was thinking about testing it, I was just wondering if this was enough of an indication that my speakers would probably be safe how I have them set. Since I don't have the input sens all the way up, I'm guessing I'm not using all of the power available, which would make me think they'd be fine, but my logic might be wrong there since I'm a noob with all of this.

 

[winkychevelle 10+ year member]

I see what you mean and ya I was thinking about testing it, I was just wondering if this was enough of an indication that my speakers would probably be safe how I have them set. Since I don't have the input sens all the way up, I'm guessing I'm not using all of the power available, which would make me think they'd be fine, but my logic might be wrong there since I'm a noob with all of this.

well the gain knob isnt a power knob in some cases u can have the amp all the way down and still be getting rated power. if u hve a headunit with 2v rca outs then you should be just about right but if its 4or5v outputs then you prolly have the amp turned up to much. the idea behind that knob is to calibrate when that amp makes full power.if u wanted it to make full power at volume #1 then it would have to be turned up quite a bit where as on the same unit at #30 it might be all the way down. read the sticky on setting gains i believe it is inn the amplifier discussion forum section