I just installed a new HU, speakers, and an amp. The speakers are rated for 60W rms and the amp is 50W rms. Does this mean that I could crank the gain to max, crank the volume to max, and the speakers won't blow or distort?

Does a gain setting of 0 mean the amp is not doing anything? That's where I have it now and quite frankly, it sounds good.

Finally, is a ground resistance of 10 ohms too much? I used one of the seat bolts but I didn't sand it first, so it's showing 9-10 ohms.

 

Gain controls are used to match the preamp levels of the headunit to the amplifier,
or sometimes to balance systems with multiple amplifiers. There is much on the
web about setting gains. Here's one link.
As for your ground resistance, 10 ohms is WAY too much. Should be well under 1 ohm.

 

Thanks for the link. I understand the procedure for setting gain, I'm just curious how reckless I can be (or my passenger) with the volume knob. Since my speakers can handle more than my amp provides, theoretically I should be able to crank it with no problems, right? I also want to know if my amp is providing any benefit when gain is set to 0.

I figured 10 ohms was excessive.

 

Your amp can't produce more than its rated power regardless if where you set the
gain. It is possible to set the gain such that the amp can't produce its rated
power no matter how high you turn up the volume on the headunit; conversely, if
you go the other direction the amp will max out before you have turned up the volume
all the way on the headunit, in which case you a) run the risk of driving the amp
beyond its capacity, in which case you will send a distorted signal to the speakers
which could theoretically damage them and will certainly sound lousy; and b) you'll
be driving the amp with a lower-voltage signal, which theoretically will have a worse
signal-to-noise ratio. Either way, you are decreasing your sound quality without
increasing your undistorted output.

 

10 ohms is bad - you should get close to 0 as possible... i check battery ground as they are very poor from factory on s2000

gain is not a volume knob, as stated before it is match voltage inputs from radio, to do it correctly you should use a o-scope, but that is rarely done,

 

Thanks guys. I was afraid that I wasn't using my amp to it's full capacity, I didn't realize that the amp could be driven beyond capacity. I'll use a multimeter tomorrow to set the gain using this formula: V = Sqrt(Wrms x R)

 

Here is the best easist way to set gains.

search for 0db test wav files at 1000 hz and burn to a cd and start it playing in a loop.

turn down amp gain to minimum
turn up head unit until sound clips. With the test tone it is very easy to hear the sound will change dramatically when it clips. Back off a little and note the volume level and never turn the head unit higher again.

With the head unit set to the highest "non clipping" level start turning up the amp gain until you hear it clip this is the max safe level.

generally you will find the max levels around 75% but it is the distortion (clipping) that blows speakers so it is good to know how far you can safely crank the volume.

 

All of the above it true. However a properly tuned system should be able to be turned all the way to Max volume on the HU without damaging anything or sounding awful. Its the safest way to do it. Its takes a while to get it right... you just have to stick with it. Its better to have a HU that can make adjustments. It is a bit tricky on the analog adjustment knobs to get it just right, but it can be done.

I've found using a mic setup and running pink noise a great way to really tune a system.

 

Anyone ever hear of a tri-way speaker connection (2 speakers + a bridged sub on a 2 channel amp) ? I have an excessively powerful Kenwood amp and I'm considering using some of that excess power on a sub. I know it's not an ideal setup but has anyone tried it?

 

I would not recommend doing that. You will have problems and more than likely damage something as the amp is not designed to run like that.

BTW how do you figure you have excess power from that amp?? You stated your speakers are rated at 60watts but the amp make 50watts... am I missing something? For all intents and purposes you've under powered the door speakers by 10 watts... although if you ask me and most guy that have been doing this gig for a while will tell you its always better to over power the speakers rather than under power them.

Just get a second sub amp and do it right.