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Why do you use a 50 or 60 hz test tone to set an amp whether then the lowest frequency the given speaker will be producing?

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I dont know the answer to this but wanna take a shot, I know more experienced and knowledgeable people in this field will chime in. I think its because it takes more power to make lets say a 20 or 30Hz to get as loud as 60Hz. So if you set it at 20Hz when your reaching full output at that frequency level, then you will probably be throwing to much power to the sub when it its a 60Hz tone or start clipping the amp. IMO but I may be wrong, Im waiting to see what the answer to this is.

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I was always curious too, doesnt the sub usually move further at lower frequencies given the same power?

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Because people seem to believe that is what multi meters are meant to measure is 50 or 60Hz.

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I dont know the answer to this but wanna take a shot, I know more experienced and knowledgeable people in this field will chime in. I think its because it takes more power to make lets say a 20 or 30Hz to get as loud as 60Hz. So if you set it at 20Hz when your reaching full output at that frequency level, then you will probably be throwing to much power to the sub when it its a 60Hz tone or start clipping the amp. IMO but I may be wrong, Im waiting to see what the answer to this is.

i am too, but thanks for the attempt

I was always curious too, doesnt the sub usually move further at lower frequencies given the same power?

yes i believe so

Because people seem to believe that is what multi meters are meant to measure is 50 or 60Hz.

true lol

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Hmm good question, . .

i'd like to see this answer too. i'm going to guess at it though.

The gain will have the same output for 30 or 60 hz , and it doesn't matter which one you use.

And will drawl the same voltage for either hert.

Just a hypothesis. i rely have no idea.

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1000 watts at 20 hz is the same as 1000 watts at 60 hz. If you use different frequencies but at the same reference level you will achieve the same output of the amplifier no matter what. It's just that somebody had to pick a frequency, and 50 or 60 hz I guess seemed easiest. Perhaps there are more readily available 60 hz tones than 20 hz ones.

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1000 watts at 20 hz is the same as 1000 watts at 60 hz. If you use different frequencies but at the same reference level you will achieve the same output of the amplifier no matter what. It's just that somebody had to pick a frequency, and 50 or 60 hz I guess seemed easiest. Perhaps there are more readily available 60 hz tones than 20 hz ones.

so if i understand this correctly. youre sayin it doesnt matter where u set it, it will play the same at either frequency?

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

Were both test tones of the same reference volume? Like both -3db, not something like the 50 hz tone at 0 db but the 35 hz tone at -6 db?

But I'll look around too and see if I'm wrong.

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

Were both test tones of the same reference volume? Like both -3db, not something like the 50 hz tone at 0 db but the 35 hz tone at -6 db?

But I'll look around too and see if I'm wrong.

its just a question. somebody asked on another forum what tone to use and i said 50 or 60 and somebody else said u need to use the lowest frequency it will b producing. so im just askin the question, which 1 is rite?

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Because people seem to believe that is what multi meters are meant to measure is 50 or 60Hz.

I personally wouldn't trust a cheap DMM to measure rather accurately at other frequencies.

1000 watts at 20 hz is the same as 1000 watts at 60 hz. If you use different frequencies but at the same reference level you will achieve the same output of the amplifier no matter what. It's just that somebody had to pick a frequency, and 50 or 60 hz I guess seemed easiest. Perhaps there are more readily available 60 hz tones than 20 hz ones.

so if i understand this correctly. youre sayin it doesnt matter where u set it, it will play the same at either frequency?

If you had a resistive load, yes it would have the same voltage output, no matter the frequency within the amps specified bandwidth. A speaker is an reactive load, so the impedance will change across the bandwith a lot when playing test tones.

i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

Were both test tones of the same reference volume? Like both -3db, not something like the 50 hz tone at 0 db but the 35 hz tone at -6 db?

But I'll look around too and see if I'm wrong.

its just a question. somebody asked on another forum what tone to use and i said 50 or 60 and somebody else said u need to use the lowest frequency it will b producing. so im just askin the question, which 1 is rite?

I don't understand the idea behind the 'lowest frequency it will be producing', because that way you'd have to set it at some absurd frequency. IMO, you should do it with your ears. Your ears should tell you when you are clipping the amp or sending the subwoofer too much power.

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

did you have any filters on? what amp was it? was there any eq?

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Because people seem to believe that is what multi meters are meant to measure is 50 or 60Hz.

I personally wouldn't trust a cheap DMM to measure rather accurately at other frequencies.

I'll give you that, but it seems whenever I see this type of topic people make it sound like that is all they can measure. Granted cheap DMM's only have a certain range of accuracy like ~45 to 1000Hz. I've had so much as a person tell me they are only accurate at 60Hz because that is what 90% of the world uses for their home lines.:Doh:

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

did you have any filters on? what amp was it? was there any eq?

The Phase is on O, the Bass EQ is on 0db, Sub Sonic Filter set around 21 hz. its on a hifonics 1610d. both of the test tones were 0db. they r the ones off of realmofexcursion.com.

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Why do you use a 50 or 60 hz test tone to set an amp whether then the lowest frequency the given speaker will be producing?

Because it is typically in between your sub-sonic and LP filter. If you are using an oscilloscope you are best off setting your gains with all the filters off.

It is also dangerous to set the gains at "the lowest frequency" for your system. The subs excursion will be at its maximum here and perhaps it won't actually take the power you are giving it if you are using a 0dB tone. 50-60Hz is much safer for that reason. In particular if you have a ported enclosure you need to be well above the port tuning as well so that the box doesn't unload and destroy the driver.

If you set gains by your ear, which IMO is the only real way to do it, then it is also dumb to use a low frequency tone as your hearing is not as good at lower Hz. Of course, the reason I set by ear is to blend together with my front stage. I am not into getting output out of my sub as IMO that is not at all why I have them, but instead I use the sub to fill in where my midbass falls off. If you are into max output then an oscilloscope is truly the way to go.

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i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

did you have any filters on? what amp was it? was there any eq?

The Phase is on O, the Bass EQ is on 0db, Sub Sonic Filter set around 21 hz. its on a hifonics 1610d. both of the test tones were 0db. they r the ones off of realmofexcursion.com.

Try turning the subsonic off and remeasure.

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Because people seem to believe that is what multi meters are meant to measure is 50 or 60Hz.

I personally wouldn't trust a cheap DMM to measure rather accurately at other frequencies.

1000 watts at 20 hz is the same as 1000 watts at 60 hz. If you use different frequencies but at the same reference level you will achieve the same output of the amplifier no matter what. It's just that somebody had to pick a frequency, and 50 or 60 hz I guess seemed easiest. Perhaps there are more readily available 60 hz tones than 20 hz ones.

so if i understand this correctly. youre sayin it doesnt matter where u set it, it will play the same at either frequency?

If you had a resistive load, yes it would have the same voltage output, no matter the frequency within the amps specified bandwidth. A speaker is an reactive load, so the impedance will change across the bandwith a lot when playing test tones.

i used 50 hz test tone when i did my gain and then i used a 35 hz test tone and my voltage was different. i dont remember what the numbers were but i believe it dropped down like 10 volts.

Were both test tones of the same reference volume? Like both -3db, not something like the 50 hz tone at 0 db but the 35 hz tone at -6 db?

But I'll look around too and see if I'm wrong.

its just a question. somebody asked on another forum what tone to use and i said 50 or 60 and somebody else said u need to use the lowest frequency it will b producing. so im just askin the question, which 1 is rite?

I don't understand the idea behind the 'lowest frequency it will be producing', because that way you'd have to set it at some absurd frequency. IMO, you should do it with your ears. Your ears should tell you when you are clipping the amp or sending the subwoofer too much power.

Why do you use a 50 or 60 hz test tone to set an amp whether then the lowest frequency the given speaker will be producing?

Because it is typically in between your sub-sonic and LP filter. If you are using an oscilloscope you are best off setting your gains with all the filters off.

It is also dangerous to set the gains at "the lowest frequency" for your system. The subs excursion will be at its maximum here and perhaps it won't actually take the power you are giving it if you are using a 0dB tone. 50-60Hz is much safer for that reason. In particular if you have a ported enclosure you need to be well above the port tuning as well so that the box doesn't unload and destroy the driver.

If you set gains by your ear, which IMO is the only real way to do it, then it is also dumb to use a low frequency tone as your hearing is not as good at lower Hz. Of course, the reason I set by ear is to blend together with my front stage. I am not into getting output out of my sub as IMO that is not at all why I have them, but instead I use the sub to fill in where my midbass falls off. If you are into max output then an oscilloscope is truly the way to go.

thank you!!! fing05.gif

so this will go for setting components as well (he said use the lowest frequency as well, instead of a 1000 hz tone)?

Edited by sostl

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You HAVE to use a frequency that is well within the passband of the crossover for gain setting. I'd also NOT pick the lowest again as you will really stress your woofer if you are pushing the limit.

Typically 1000Hz is a good number for a component set as you will be above the HP and well below the LP. 500Hz would be fine as well though.

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You HAVE to use a frequency that is well within the passband of the crossover for gain setting. I'd also NOT pick the lowest again as you will really stress your woofer if you are pushing the limit.

Typically 1000Hz is a good number for a component set as you will be above the HP and well below the LP. 500Hz would be fine as well though.

thank you again.

just wanted to ask some real knowledgable people that actually know what their talking about!!

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Why do you use a 50 or 60 hz test tone to set an amp whether then the lowest frequency the given speaker will be producing?

Because it is typically in between your sub-sonic and LP filter. If you are using an oscilloscope you are best off setting your gains with all the filters off.

It is also dangerous to set the gains at "the lowest frequency" for your system. The subs excursion will be at its maximum here and perhaps it won't actually take the power you are giving it if you are using a 0dB tone. 50-60Hz is much safer for that reason. In particular if you have a ported enclosure you need to be well above the port tuning as well so that the box doesn't unload and destroy the driver.

If you set gains by your ear, which IMO is the only real way to do it, then it is also dumb to use a low frequency tone as your hearing is not as good at lower Hz. Of course, the reason I set by ear is to blend together with my front stage. I am not into getting output out of my sub as IMO that is not at all why I have them, but instead I use the sub to fill in where my midbass falls off. If you are into max output then an oscilloscope is truly the way to go.

Thats what I was trying to say, it just didnt come out that way

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Typically 1000Hz is a good number for a component set as you will be above the HP and well below the LP.

Plus it's easy to tell if the signal is clipped / distorted or not.

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