Calculated Wattage Output. How far would you take it with my setup?

[n2audio 5,000+ posts]

not true....need a dmm and a birthsheet

Or just a DMM and a quality (accurately or conservatively rated) amp.

Not everyone has access to these pieces of equipment. Especially a O-scope.
And to even think that the average car audio user can't setup there equipment without it is, well retarded.

x2

It seems many others agree with you. I was under the impression that the gain setting thread was the accurate way to do things.

It is simple and effective, and going with the -3db tones IMO is "pusing it" as far as you should push it.

you can also detect clipping with a DC DMM measuring the DC Volts going to your speakers it should be minimum, should be all AC if you are noticing a great deal of DC then either your meter is inaccurate or you are clipping the output signal, don't put it past your meter to be inaccurate, the only meters I trust are my Fluke meters.... have seen strange things with all other brands of meters....).

Considering clipping is not DC - it is high frequency AC - how does this work?

 

[dB-r 10+ year member]

No way to know what output you have without both measurements. And birthsheet means nothing, all test circumstances are different and all systems impedances change with frequency etc etc... geez why do I even bother with these kinds of posts.

And yeah thinking about it now you are right about one thing, clipping is high freq AC so probably won't show up on a DMM on DC volts at all.

If you are a "normal" car audio guy no need for a scope, no, but if you are crazy you need one so you can "see" if your signal is being clipped or not, how can you argue with that? Maybe I am missing something? Those Velleman HPS10 are find for setting gains and other things and are only like $100, if you are crazy I recommend you get one, or come by my shop, you can borrow mine, I don't use it for anything on the bench as it is no where near as good as regular benchtop scopes, but does the job for measuring output signals to set gains etc.

 

[davidt487 10+ year member]

where are you located? texas is a big state

 

[badstang123 10+ year member]

I use two meters at once, they are Fluke 73III one has the 400A AC Fluke Clamp on it. You can use a cheap portable LCD O-Scope like the Velleman HPS10, I think you can get them for about $100 and will come in handy for all sorts of things not just setting gains, but that is one use, yes and yes to avoid clipping entirely you will need to adjust your gains properly with the scope, relying on your ears is good enough too (for most, some are more anal types and want to make 100% sure it's perfect, but as someone else pointed out here setting gains is a waste of time, it's really NOT necessary to be so anal about it unless you are a super duper sound quality freak, you can just set it by ear as long as you are experienced and have a good ear for clipping, you can also detect clipping with a DC DMM measuring the DC Volts going to your speakers it should be minimum, should be all AC if you are noticing a great deal of DC then either your meter is inaccurate or you are clipping the output signal, don't put it past your meter to be inaccurate, the only meters I trust are my Fluke meters.... have seen strange things with all other brands of meters....).
AC Volts x AC Amps = power output in watts

AC Volts / AC Amps = Actual impedance amplifier is seeing from the load at that specific frequency

So if I'm understanding you correctly you are doing this with the speaker hooked up instead of disconnected, as was explained in the other gain setting tutorial? And I would assume that you do this so you are getting more accurate feedback since the driver is connected as it would be during regular playback? Also, are you doing this while using a 1K sine wave or using a regular musical track with a wide range of highs and lows? And finally, if the answer to the previous question is a 1k sine wave do you risk damage to the speaker by having it hooked up and doing this? (I would just think the voice coil would heat up a lot under that kind of load) But again. I'm all ears.

And just so you know. You're posting in this thread because I listen and am eager to learn //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif For what that's worth. Thanks.

- Justin -

 

[gotparts90 10+ year member]

If you had AC voltage in your speaker you would be in a lot of trouble ! //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif


WB

just WOW how dumb just wow.

 

[dB-r 10+ year member]

Yes, you have to have the driver hooked up because without it there is no load on the amplifier.

You use a frequency range (using just tones), appropriate for your drivers. If your driver operates around 100hz and down you use 100hz and down tones, if it uses 1K and up tones you use 1k and up tones.

 

[n2audio 5,000+ posts]

No way to know what output you have without both measurements. And birthsheet means nothing, all test circumstances are different and all systems impedances change with frequency etc etc... geez why do I even bother with these kinds of posts.

I really don't know. Few people WANT to mess with a scope to set their gains, and even less NEED to.

Birthsheets mean something, so do power ratings of quality amps. Either of those and a DMM works fine.

If you are a "normal" car audio guy no need for a scope, no, but if you are crazy you need one so you can "see" if your signal is being clipped or not, how can you argue with that? Maybe I am missing something?

I wouldn't call it arguing. I just think it's a waste of time and money.

A lot of people seem to be getting their panties all in a bunch lately about setting gains. It's really not that complicated.

 

[dB-r 10+ year member]

I think it's not really even necessary, I was just advising the guy of the correct and most accurate way to do it. And if I recall correctly, you just like arguing with me.... LOL..

 

[badstang123 10+ year member]

Yes, you have to have the driver hooked up because without it there is no load on the amplifier.
You use a frequency range (using just tones), appropriate for your drivers. If your driver operates around 100hz and down you use 100hz and down tones, if it uses 1K and up tones you use 1k and up tones.

Thank you

 

[dB-r 10+ year member]

Your welcome.