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    Icon32 How loud is 500 RMS of ~50 Hz?

    That's the question.. Say in a sealed box for the 12"s..

    I'm trying to see how much power the system will be eating from the Alt, but I'm trying to look at 2x12" @ 500 RMS (peak) and 2x10" @ 400 RMS... If I'm not mistaken, isn't that 1800 RMS? .. The amps are 2x500 RMS @ 2 ohm, one amp for each pair of speakers..

    So, how loud is that? is that a lot more than I will ever use for normal listening (the rest of the system is stock, the bass will be turned down on the HU so the stock speakers can run louder than they do now without distortion)...

    I don't have access to my bookmarks at the moment, so I can't find the calculator I'd normally try to use to get the dB level

    Any help would be much appreciated.. I'm in the process of trying to decide if 2 of the smaller amps are ok (2x500 RMS @ 2ohm) for all 4 speakers, of if I need to get one small one and one that's a bit bigger for the 12"s (2x650 RMS @ 2 ohm).. But, if I'm not gonna be turning up the system that high for a LONG while (read: once I get enough money to change out the factory comps) then I probably don't need the bigger amp for the 12"s (the small one 'should' run them, but I"m sceptical about 500RMS @ 2ohm).. Then, there's an amp I was looking at.. 800RMSx2 @ 2ohm.. just to make sure I have room to grow

    But, at 3200 RMS... (or so I think).. that's a LOT for an electrical system.. not sure I could ever run it without serious alterations (extra Alt? more batteries? etc etc)..

    Anyway... Probably a dumb question ...


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    Hmm.. yeah.. then it probably won't ever get turned up that high.. for now

    Guess I'm overkilling it here a bit..

    But, then.. next stupid question.. I recall seeing that if you have your gain turned down that you make the amp work harder.. is that only if you try to get it close to max power again? What I'm getting at is, I have to have some way to make the bass much quieter than the rest of the system (if full RMS is '). Isn't that what the gain is meant for? to restrict the input signal so the output signal is lower? If it's not gain I'm thinking about, then how would I control the pre-amp outs from the HU so the bass doesn't eat up all the rest of the music?




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    so.. 'gain' is an internal multiplier to the input signal? so that if I had a 4 volt going in, and the gain set at 4 volt (would that be the middle) all is good in the world of amp.. if I turn up the gain.. a 1 volt signal in 'looks like' a 4 volt signal because the gain mechinism magnifies that 1 volt in?.. To go the other way.. if I turn down the gain.. a 4 volt in looks like a 1 volt in (meaning I get quieter out) which doesn't cost anything in the world of amp...

    so.. if I have input ranging from 1 - 5 volt (just say).. gain at middle passes that straight to the amp circuts.. If I turn 'up' the gain.. 1 - 5 volt might look like 3 - 8 volt? If I turn down the gain.. 1 - 5 might look like 0.2 - 3 volt?.. that the idea?

    (Sorry.. bored here at work, figured I might as well learn something useful )




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    I think I kinda get it..

    If I have the gain turned down so it matches the rest of the system I will clip the signal if I try to crank it too much.. the 'rails' (fuzzy on that, sorry) are set to a max of say 1 volt.. if I turn it up too much and send a 2 volt signal in I clip?..

    Hmm.. now I'm confused again.. If the pre-outs put out a max of 4 volts.. and I have the system turned up, say, 75% (point where the stock speakers get twitchy).. I have 3 volts on the pre-outs.. correct? but if turning down the gain lowers the max signal you can get in cleanly then setting it to one volt will cause clipping, won't it? If I turn up the gain to (work with me) 10 volts, i have a LOT of room, I'm that much farther below the 'required' signal for max output.. that's better in this case, right? I mean.. if I had the gain set at 3 volt, and I had the system at 75 % (3 volt on the pre-outs).. the amp would be maxed (for RMS.. ~500 each sub).. if I set the gain to 1 volt, I'd be clipping.. right?.. if I set it to 9 volts, I'd only be at 1/3 full power (~165 RMS each sub).. is that right?.. so 'turning down the gain' is increasing the voltage needed to reach max power?

    *sigh* sorry.. some things are hard to explain to dolts like me who don't have the proper backgroud for this stuff.. circuts/ohms/watts/amps/volts/AND gates/OR gates/XOR gates/etc/etc.. I don't get that stuff as well as I'd like.. and knowing which way this goes when that goes the other way.. I get lost easy...

    But, is that the right idea (the last set).. turning 'down' the gain raises the max rail voltage needed for max power so that the pre-outs can never get that much juice out?

    *hopes that's right as he senses he's about to get pounced on if he's still not got it*




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    Oh.. and back to the main point a bit.. kinda..

    If I have 2 500 RMS 12" and 2 400 RMS 10".. is that really 1800 RMS? or is total RMS the max of any given part? I mean, as far as volume goes.. I only noticed a 2 or 3 dB increase on one of the calculators I was looking at one day when I added a second 12" of the same size/power .. I know I have 1800 RMS as far as the electrical goes, that's how much power is being ****** out of the system.. but as far as 'loud'.. it's really only as loud as the best RMS in the set-up.. right? with marginal increases with adding in more of the same? That is, 1 12" might go 130 dB, add another of the exact same and get 135 dB.. add a 3rd and get 137 dB.... so you don't really have, say 3 x 500 or 1500, you have 1 x 550? as far as loud goes...

    k.. I think I'm done making people pull their hair out now




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