proper way to set your gains

btw, i found the read i was looking for: So many people have their amp gains set wrong, and to be honest setting them by ear is quite a crapshoot. Doing it properly with a multimeter is actually quite simple. Here's how you do it: Set head unit volume to 3/4 of maximum. Turn off all eqs/presets in the head unit. DISCONNECT SPEAKERS P = Power in watts I = Current in amperes R = Resistance in ohms (effectively the nominal impedance) V = Potential in volts (Voltage) Knowns: Resistance (nominal impedance of your speakers) Power (desired wattage) Unknowns: Voltage (we'll measure this) Current Formulas: P = I*V (formula for power) V = I*R (Ohm's law) So after a little substitution to get Voltage in terms of simply power and resistance we get V = square_root(P*R) So, for example, say you have a 4 ohm load presented to a 150 watt amp. V = square_root(150*4) = 24.5 volts This means you should increase the gain until you read 24.5 volts AC on the speaker outputs of your amplifier. As a source, use a sine wave recorded at 0db at a frequency within the range you intend to amplify. You can generate tones in cool edit or use a program such as NCH tone generator. (credit for NCH to imtfox, IIRC) Additionally, you could use a scope to actually check if the signal is clipping, but I'm not going to get into that here as I doubt very few people have access to that type of equipment. UPDATE: After playing around with the following programs: Cool Edit 200 Test Tone Generator NCH Tone generator It seems that NCH tone generator does not save files at 0db. The tones generated by NCH were noticably quieter than tones generated by the other two programs, which seemed to be the same level.

Yes, the 0 db reference level is the major problem I had using Frequency Generator, too.  That's why I allow that the program is good for setting crossovers, not gains.  There have been some major players here who have argued that without a scope, using a DMM for setting gain is more of a crapshoot than the ear method (varying impedances at different freqs, etc.)  Taking it all into consideration, I say that the person who does both is most likely to be accurate in the long run.

thanks for the help newtone and stevdart I set my mrd-1000 on my type x 10 today and my front type x 6.5 components on a mrv-t320 the way you suggested.... boy does it impress me.... can't wait till my other set of x components come in