Car audio Rumours
09-30-2009, 02:24 PM
#71
Jstoner: What you are saying is true, that is it's purpous because there is no standard deck output, we need a gain to decide how much or little cliping we can take and we must be able to do so with whatever deck we connect to it.
However You can do it in reverse and there would be no difference: set your deck level so that you don't clip your amp when you raise the gain 3\4's up. It would get as loud and the amp would clip just a smuch or as little. Of course the noise floor might be different if there is noise in the system but that's the only difference in my eyes.
And just so it is clear, if you set it by ear, regardless of your settings you will have some amount lf clipping. If you set it with equipement in order to have no clipping at all, the system volume would be very very low even if your amp makes big power.
However You can do it in reverse and there would be no difference: set your deck level so that you don't clip your amp when you raise the gain 3\4's up. It would get as loud and the amp would clip just a smuch or as little. Of course the noise floor might be different if there is noise in the system but that's the only difference in my eyes.
And just so it is clear, if you set it by ear, regardless of your settings you will have some amount lf clipping. If you set it with equipement in order to have no clipping at all, the system volume would be very very low even if your amp makes big power.
09-30-2009, 02:39 PM
#72
have you ever felt a true 10hz at 143db ???..
it knocks crap off of neighbours shelves from across the street
I'd love to build a 150db @ 10hz system...might do so next year
and I bet I can do it with only 3200w rms and some 15" Icons
for example four 10" SSA Icon woofers on a Crown A3000gti (3200w rms)
it knocks crap off of neighbours shelves from across the street
I'd love to build a 150db @ 10hz system...might do so next year
and I bet I can do it with only 3200w rms and some 15" Icons
for example four 10" SSA Icon woofers on a Crown A3000gti (3200w rms)
it's those well thought out set ups that drop while taking your insides
down to the floor and keep dropping after the sound dissipates and
wobbles everything are the ones that deserve to be called sub woofers
down to the floor and keep dropping after the sound dissipates and
wobbles everything are the ones that deserve to be called sub woofers
most amps with a low damping loose control down that low and requier a
sub sonic filter (think about it...a "sub" woofer with a "sub" sonic filter...LOL)
sub sonic filter (think about it...a "sub" woofer with a "sub" sonic filter...LOL)
a true damping does make a difference but you pay for it....
the power is way more $$$ per watt and the amp is usually
a power pig and a half
the power is way more $$$ per watt and the amp is usually
a power pig and a half
09-30-2009, 03:10 PM
#74
damping factor...
let's say your amp have 5000 of DF
your sub is connected to it at, lets say, 4 ohms.
so the internal impedance of the amp is 0.0008 ohm.
Unless you use a BIG wire, your actual DF is a lot, a LOT less than that.
example: 0.05 ohm of wire = 0.0008 + 0.05 = 0.0508 ohm
actual DF is 4/0.0508 = 78
ohh boy, so low...
let's say your amp have 5000 of DF
your sub is connected to it at, lets say, 4 ohms.
so the internal impedance of the amp is 0.0008 ohm.
Unless you use a BIG wire, your actual DF is a lot, a LOT less than that.
example: 0.05 ohm of wire = 0.0008 + 0.05 = 0.0508 ohm
actual DF is 4/0.0508 = 78
ohh boy, so low...
09-30-2009, 03:19 PM
#75
Administrator
Join Date: Feb 2006
Posts: 16,855
Some other observations based on what I have read the last few pages..
The correct term for a "subsonic" filter should be an infrasonic filter, but the marketeers went another way.
The Marketeers however DO like to promote damping factor though because it's easy to make an amp make a nice big number. Reality is any amp you don't get in a blister pack has more than anyone will ever need. It's kind of like the battle in the 90s to get THD into insanely small numbers far far below what anyone could hear. Yeah.. jam up the negative feedback... THAT sounded good...
The low string on a 5string bass is generally tuned to B1, or 62 hz-ish. I don't think Michael Anthony played a 6+ string bass back in the day good luck getting that 20hz bass guitar. Good range for a ported box though. Remember, ported boxes rule.
lol, servo drive.. How many wires go from the amp to the woofer? Two, or two pair? Real servo systems use two pair and are rare, the others are marketing BS.
hmmm, what else...
How about some more common myths:
Sealed boxes sound better.
Expensive cables sound better.
4v+ decks are better than common 2v decks.
09-30-2009, 03:25 PM
#76
Administrator
Join Date: Feb 2006
Posts: 16,855
damping factor...
let's say your amp have 5000 of DF
your sub is connected to it at, lets say, 4 ohms.
so the internal impedance of the amp is 0.0008 ohm.
Unless you use a BIG wire, your actual DF is a lot, a LOT less than that.
example: 0.05 ohm of wire = 0.0008 + 0.05 = 0.0508 ohm
actual DF is 4/0.0508 = 78
ohh boy, so low...
let's say your amp have 5000 of DF
your sub is connected to it at, lets say, 4 ohms.
so the internal impedance of the amp is 0.0008 ohm.
Unless you use a BIG wire, your actual DF is a lot, a LOT less than that.
example: 0.05 ohm of wire = 0.0008 + 0.05 = 0.0508 ohm
actual DF is 4/0.0508 = 78
ohh boy, so low...
09-30-2009, 03:27 PM
#77
Jstoner: What you are saying is true, that is it's purpous because there is no standard deck output, we need a gain to decide how much or little cliping we can take and we must be able to do so with whatever deck we connect to it.
However You can do it in reverse and there would be no difference: set your deck level so that you don't clip your amp when you raise the gain 3\4's up. It would get as loud and the amp would clip just a smuch or as little. Of course the noise floor might be different if there is noise in the system but that's the only difference in my eyes.
And just so it is clear, if you set it by ear, regardless of your settings you will have some amount lf clipping. If you set it with equipement in order to have no clipping at all, the system volume would be very very low even if your amp makes big power.
However You can do it in reverse and there would be no difference: set your deck level so that you don't clip your amp when you raise the gain 3\4's up. It would get as loud and the amp would clip just a smuch or as little. Of course the noise floor might be different if there is noise in the system but that's the only difference in my eyes.
And just so it is clear, if you set it by ear, regardless of your settings you will have some amount lf clipping. If you set it with equipement in order to have no clipping at all, the system volume would be very very low even if your amp makes big power.
ya i agree with you completely on that. you can do it in reverse but you would have a low level of control over your system because it would be maxing out at a 1/10th of what your volume **** goes to and it would be impractical because the noise floor would be horrible. the whole idea is so that you can minimize amplification as much as possible. ...but it would be done nonetheless.
i geuss how i was trying to explain it is that, the bottom line is, MANY people correlate the word volume with power. if you turn up the volume on your deck, you are turning up the power it is putting out. if you turn up the "volume" on your amp, you are not altering its power levels, simply adjusting the sensitivity.
and as far as clipping, i agree, tuning by ear you will always have clipping. you are just trying to minimize it while still having whatever the listeners idea is of sound quality.
....lol so long story short, i agree with you, but people shouldn't correlate volume to power. ...or if you do, recognize where it does and does not apply.
...and gain is a misleading word, thats why many amps say sensitivity, which is more accurate.
Last edited by jstoner22; 09-30-2009 at 03:31 PM.
09-30-2009, 03:29 PM
#78
500 Watt CAFz'r
Join Date: Jan 2008
Posts: 537
09-30-2009, 03:35 PM
#79
Administrator
Join Date: Feb 2006
Posts: 16,855
Sorry Kevin - I did not mean that your time was incorrect. I meant that Jordy's supposition that caps are useless is incorrect. I guess you did agree with him so I am disagreeing with you too 
My opinion: With reasonable capacity, on music, a capacitor is a worthwhile addition to a car. For a bonkmobile playing test tones, it is not.
My opinion: With reasonable capacity, on music, a capacitor is a worthwhile addition to a car. For a bonkmobile playing test tones, it is not.
