727, altho I know a DMM is not an accurate method of setting gains, and never said so, please explain your accurate method of setting amp gains.

First to determine the clipping point of my iPod (Can't use CD's because they will skip before I even make it to half tilt) I hook up my 3.5mm to RCA cable that hooks to my Eclipse AUX-105 cable and set all EQ off on the iPod and slowly roll the volume up while checking the RCA lead with my scope for the slightest hint of a clip, at that point back it off one notch and remember that volume.

Second I hook that cable to my AUX 105, set volume on iPod to predetermined volume, set all EQ's on the head unit to flat (0 on all eq settings) with subwoofer level at it's highest setting (only way to acheive maximum preout voltage on most newer head units) hook the o-scope to the RCA leads going to the amp and slowly go up with the volume till it starts to clip, then back off again one notch and remember that volume.

Third hook the amp up, set all filters to their maximum level (subsonic off), bass boost obviously off, hook up the sub leads and insert the o-scope into the positive (can be done without a load but from my experience clipping point changes under load), gain all the way down put on a 40hz 0dB track on ipod and set both volumes accordingly, turn the gain up till the slightest hint of a clip then back off till it stops clipping.

Done on that point. I also check all of my music in audacity to make sure none of it contains any major clipping as well.

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What I thought is you are using an O-Scope. Of course, an O-Scope is the best way to set gains but I can't afford an O'Scope and neither can most people. Also, most people cannot audibly detect clipping, they think they can but what they are hearing is distortion after the clipping point. Sooo... a DMM is the best way for most DIY'ers to set their amp gains. I never said it is accurate, but it gets it closer than most can do with their ears and only requires a little simple math. If they have an iPod, they just need to turn it down to 2 or 3 clicks below max volume, turn amp gains all the way down, turn the head up until they start to hear distortion, back it down until it stops, use the appropriate test tone to set the amp gains with a DMM. Also, if you set the gains with all EQ flat, the gain is not going to be set the same when the EQ is adjusted.

In a case where you can't afford an o-scope I recommend something like the SMD DD-1. The DD-1 is a great device, but my only issue with it is the tracks they tell you to use when setting gains is -5, -10, and -15 but if you use track 1 (40hz 0dB) to set the gains instead of the ones it mentions it will work nearly as well as a scope. Around the same price as a good DMM as well.

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Again, someone who is going to install an amp or 2 and wants to set the gains well enough and leave them alone after that, is not going to spend money on that. They want to use their $15 autozone DMM.

You are completely missing the point. Using a DMM is no more accurate than doing it by ear, whether you match the RMS power or not. Once you start figuring in for voltage drop, impendence rise, etc you're amp will likely not be able to do near the power it claims it should. Most amps are rated using a resistor that doesn't rise and on a 14.4v constant with no drop. If you're wired at 1 ohm nominal on an amp rated at 800watts at 1 ohm, 600 at 2 ohm, etc at 14.4v and you set the gain for 800 watts, then when your box rise comes in to affect and you rise to say 2.3ohm where your amp even if it's a high quality amp should only be doing close to 600 watts you are still clipping the signal.

If you don't want to spend the money to do it the right way set your filters correctly, turn the gain until you THINK it's right, then back it off about an 1/8th turn. I've given that advice for years and haven't seen any issues out of it. Sure it's not scientific, but it doesn't even cost $15

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I believe you are wrong about the DMM. You are thinking only in terms of highend sub systems. I do believe an oscope is the best method, and have always known that.

Impendence rise, voltage drop, etc all the factors that affect actual power output are present in all setups, and esspecially on a cheaper setup where it takes absolute perfect conditions for your amp to do rated power. DMM method may work, but I wouldn't try to do it by claimed RMS power, maybe more like 75% of it or something of the sorts. Too many variables that will interfere with getting the power they claim it can do.

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Dances with wolves is a great movie.

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I'm forced to agree.

Totally off track, have you seen the new Discovery series "The Devil's Ride" it's pretty quality. I watched a few episodes last night, I'm hooked.

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I have not. but it cant be real. just like the moonshiners show. it has to be setup

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Most likely, it's still rather entertaining though. I do parts/service at a custom bike shop, so anything motorcycle oriented draws my attention to begin with.

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Man, I wish I got that channel !