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I have a HP Voltmeter.... now what?


Coytee

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I've had this for probably 3 years? I've not even looked at it for 2 years. It is probably the 400GL verses the F model.

I don't even remember exactly why I bought it. So... now, I wonder..... here I have this. Just exactly what might I use it for? Is it really something that is going to be terribly useful to a techno-stupid person like me?

Keep it, sell it, donate it?

HP 400.pdf

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it may come in handy for reading power going into a speaker, or AC voltage, and the like

Ok... notice I did admit to being techno-stupid. How would I read the power going into the speaker? (something that would interest me a small amount) Would I put it on the leads to the drivers as the speaker is playing?

Given that I'm biamping, how would I correlate the power being used with the fact that I have two sources of it? If for example, the HF is using 4 watts and the LF is using 16 watts... would I simply defer to say that I was listening while using 16 watts since it's the higher number? (meaning, I don't think I add them and say I was using 20 watts)

I really wasn't kidding when I said techno-stupid [:D]

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How would I read the power going into the speaker? (something that would interest me a small amount) Would I put it on the leads to the drivers as the speaker is playing?

Hook the VM leads to the speaker. With the VM on AC volts take a reading with music playing. You will see less than 1 volt in most cases (with efficient speakers like yours). Multiply the voltage reading by itself then divide by the impedance of the speaker. The result is the power in watts going into the speaker, usually way less than one watt with Klipsch.

Given that I'm biamping, how would I correlate the power being used with the fact that I have two sources of it? If for example, the HF is using 4 watts and the LF is using 16 watts... would I simply defer to say that I was listening while using 16 watts since it's the higher number? (meaning, I don't think I add them and say I was using 20 watts)

You add the two power readings together to get total power going into the speaker system.

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The result is the power in watts going into the speaker, usually way less than one watt with Klipsch.

Heh... you need to Honk your Horn loving Hiney to my place once.... just once.... [A] [8]

You add the two power readings together to get total power going into the speaker system

So, as per the scenario of 4 watts going to HF and 16 going to LF, you would then find it accurate to say that I was using 20 watts at that given time? I would have thought since the 4 watts only brought the HF up to sonic par with the LF that it wouldn't be additive.

Mind you, not that it really matters, I'm just showing my thinking patterns.

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I agree that is a good idea. Also, you can use the current part of the meter and see how much current is going to you speakers. So, if you take your voltage and multiply it times your current, you just might get a rough idea of the power that your using (watts). The biggest and most interesting thing you will notice is how LITTLE voltage and current your using compared to what everyone "says" you need. If for example you are using approx 1 or 2 watts, you need headroom of approx 20 times that, or about, 80 watts. See? you don't really need 400 watts per channel with a Klipsch set up. Now if you had speakers with an 86 or 87 DB sensitivity, then you would need a ton of power.

The reason you want 20X your normal listening power is so when you have a spike in the sound (home theater!) your system can deliver what sounds to your ears as a perfect spike in the system. This will happen even though technically that spike could be a 100X spike. You will not hear it as your ears are not as sensitive as an O-scope. So, get out your meter and have fun. Oh and make SURE, DOUBLE SURE you don't let any strands of wire touch across the terminals as you will instatnly blow out your output transistors. It takes about 1/100th of a second and they are gone! Good Luck!!!

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I have a Fluke Multimeter. Had it for about five years. What should I do with it?

I've had this for probably 3 years? I've not even looked at it for 2 years. It is probably the 400GL verses the F model.

I don't even remember exactly why I bought it. So... now, I wonder..... here I have this. Just exactly what might I use it for? Is it really something that is going to be terribly useful to a techno-stupid person like me?

Keep it, sell it, donate it?

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Richard - I always use my meter to check and make sure a circuit is dead after I flip a breaker.

Neo - I've had my Fluke for about 15 years and use it all the time.

Depending on the model:

Checking resistance (these meters are autoranging which is nice)

Check voltages (AC or DC)

Current (up to 10 amps, but the meter has to be in the circuit unless you measure the voltage across a known resistor and calculate the current [how amps like Dynaco measure bias current]. A simple ohm's law pie chart is a handy thing. You can find one on line)

Some will measure frequency, but mine only will do 60Hz.

If you get a tool, you should learn what all it can do and how it can help you. I want a scope, but for the few times I need one, I can't justify the cost.

Bruce

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Just exactly what might I use it for? Is it really something that is going to be terribly useful to a techno-stupid person like me?

If your so inclined and willing to obtrain a signal generator, a frequency counter and a couple of resistors you can measure loudspeaker impedance using the constant current method which calibrates the reading of your AC meter to impedance.

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