how to tune an amp

[jharijan 10+ year member]

Can anyone explain to me how to accurately set an amp's gain?

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[mr.michael 10+ year member]

yea hold on ima post a vid

 

[mr.michael 10+ year member]

for subshttp://www.youtube.com/watch?v=xSUuBBJQ4Wk

for mids and highshttp://www.youtube.com/watch?v=tQDEkxD8ed8

 

[jharijan 10+ year member]

aren't oscilloscopes a little pricey?

 

[mr.michael 10+ year member]

yea they are but it beats taking your stuff to a shop. i hate shops. they act like YOUR equipment is theirs. im gonna get one eventually. just dont turn your stuff up that high and you should be ok until you set them properly

 

[jharijan 10+ year member]

there was a good link on the these forums about setting the gain but didn't really cover much on how to tune the bass boost, sub sonic and lpf on the amp

 

[thehardknoxlife 10+ year member]

You could do what 90% of the people here do and set it by ear.

Or you could read the Gain Setting Tutorial for the DMM method. Which is a sticky I might add.

The bass boost is easy, set it to 0. Subsonic is also pretty easy, just set it 5-10hz below the tune of your enclosure. If you hear the woofer making mechanical noise with low notes (below your box tune) turn it up more. LPF can be different depending on how high YOU like your sub to play, most people just set it between 70-80 hz. All this can be found numerous times via the search bar in greater detail.

 

[jharijan 10+ year member]

this might be a stupid question but how to you find the tune in hz of the enclosure?

 

[thehardknoxlife 10+ year member]

this might be a stupid question but how to you find the tune in hz of the enclosure?

The short and easy route would be to enter the box specs into an online calculator. It won't be 100% accurate but it doesn't have to be if it's just for setting the SS filter. I'd just set it to 20hz, thne work my way up if need be. If it's a sealed box then the SS filter needs to be off.

 

[Mass Car Audio 10+ year member]

aren't oscilloscopes a little pricey?

Depends if you buy a new one or a old school one. I got mine for $15 + shipping on ebay and it works like a charm for all my repairs I do.

 

[jharijan 10+ year member]

You could do what 90% of the people here do and set it by ear.
Or you could read the Gain Setting Tutorial for the DMM method. Which is a sticky I might add.

The bass boost is easy, set it to 0. Subsonic is also pretty easy, just set it 5-10hz below the tune of your enclosure. If you hear the woofer making mechanical noise with low notes (below your box tune) turn it up more. LPF can be different depending on how high YOU like your sub to play, most people just set it between 70-80 hz. All this can be found numerous times via the search bar in greater detail.

How do you accurately tune the sub sonic and lpf because on my amp there is like 40hz on one side and 200 on the other with nothing in the middle, like this http://www.mtx.com/caraudio/products/manualsQuickInstall/amps/XT_600XD_300XD_InstallSheet.pdf

how do you know your at the number you want to be at?

also I've heard some people say tune it 5-10 hz below the tuning of your sub and some say the tuning of your box, which one is correct? for a box tuned at 35hz below would be 25-30 right, now the other way.

 

[thehardknoxlife 10+ year member]

How do you accurately tune the sub sonic and lpf because on my amp there is like 40hz on one side and 200 on the other with nothing in the middle, like this http://www.mtx.com/caraudio/products...stallSheet.pdfhow do you know your at the number you want to be at?

also I've heard some people say tune it 5-10 hz below the tuning of your sub and some say the tuning of your box, which one is correct? for a box tuned at 35hz below would be 25-30 right, now the other way.

Be a good guesser, lol. Just use your ears man. If you think the sub isn't playing high enough for your taste, turn it up. If you feel it's playing too high, turn it down.
Regarding the SS filter, I can't remember the rule of thumb off the top of my head. It's something like 1/3 octave below the box tune, although don't quote me on that. To be honest, you don't really have to worry about it, just turn it off. Now if you listen to music that dips under 20hz often then it might be a problem(although I doubt it), but since almost no one uses frequencies that low it shouldn't really matter. I'd just turn it down, then if you ever hear mechanical noise on a low frequency, turn it up a bit. A high tuned box, and a shitload of power is really the only time you'd need it.

Oh and your link doesn't work.

 

[jharijan 10+ year member]

to find the voltage for the gain you multiply the rms watts by the ohms of your speakers then find the square root of that number right? if i'm wiring two 4 ohm subs to create two ohms would I multiply my amps watts by 2 or 4? That might have been a bit confusing, here is the specs of my setup.

600 watt rms x 1 amp @ 2ohms, two 4ohm speakers that will be wired at 2 ohms.

 

[jharijan 10+ year member]

anyone?

 

[phemps 10+ year member]

Depends if you buy a new one or a old school one. I got mine for $15 + shipping on ebay and it works like a charm for all my repairs I do.

!!!!! thats amazing i want an oscil for this **** cheap ha sounds like quite a deal im surprised at that cheap it works. handheld? or a full osciloscope?