Clipping, Setting gains = Confused

[RLB910]

Hi, new here and this is second post.

I have been trying to get my system straight and the vid Steve has on setting gains with an O-Scope helped me understand those things better than ever. Thanks Steve.

Now on to my confusion but first let me give you my system.

Alpine IVA-D901 HU

Alpine PXA-H701 Digital Processor

Alpine MRV-F345 4 channel amp 75 watts RMS per 4ohm

Alpine MRD-M605 Mono amp 600 watts RMS 2ohm

Cadence CVL-6K 6" front

Infinity Kappa 462.9 CFP 4X6 REAR

Alpine SWR-1042D in a sealed enclosure.

Part of my problem is my volume control. When it is at full volume it produces 5.4 volts no clipping, yes I said no clipping on 1k test tone 0 db and a 40 test tone 0 db. (the HU is rated 4v so not bad). Now what is messing me up is how the volume indicator looks ( http://img233.imageshack.us/img233/8960/120ymp.jpg ). The last bar before it goes yellow is level 24. The last bar before it go red is 28. Where would y'all set the volume at before setting gains?

The second part in my confusion is the HU sub control ( http://img828.imageshack.us/img828/6862/123tcf.jpg ). I set the gains with it at 0. The last bar before yellow is level 9 and the last bar before red is level 11. Now as I am running the test tone and have the gain set at now clipping I wanted to see what would happen by turning up this control. I clip as soon as I move it. When I listen to anything I here a little bass so I have to turn it up to get any real response out of the sub. So I set gains with it at level 9. Now when I turn it down I have VERY little to no bass. To hear any bass and get the sub to respond I have to go past 9 which would clip the test tone. So where do I set gains at and how do I know I will start clipping the signal. different music and different sources all have different levels. Even my CD's have different levels depending what year they were pressed. A CD from the 80's is not as load as a CD pressed today.

All of the EQ settings are flat and all enhancers Alpine has are off. And volume was set at level 24.

So how do y'all do it? How do you set gains on you systems and be able to turn up you Epicenters without clipping? My mono amp clips at 34.7 volts and my 4 channel clips at 17.4 volts. How do I set mine up so I can use the sub control, get good solid bass and not worry about clipping?

Thanks

[zrkie]

Im currently fooling around with the same type of 'thinking'.

This is how I see it: If u metered the HU with volume at max, 35 with no clipping. Great. With Subw Level at 15 and volume at 35, do you get clipping? If not, then this is where u want to be.

The subwoofer level control usually only regulates the output of the subsignal, without adding filters. Therefore, it should be fine to run it at max as long as it doesnt clip.

[RLB910]

Im currently fooling around with the same type of 'thinking'.

This is how I see it: If u metered the HU with volume at max, 35 with no clipping. Great. With Subw Level at 15 and volume at 35, do you get clipping? If not, then this is where u want to be.

The subwoofer level control usually only regulates the output of the subsignal, without adding filters. Therefore, it should be fine to run it at max as long as it doesnt clip.

I did look at that. With volume at max ans sub control at max the amp clips. Lower either one of those out of the red, if you looked at the pictures, and I get no clipping. At that setting the amp is at its minimal setting of 8 volt input. If I set the amp at 4 volt input then the other control needs to get out of the red. Either way I don't get ANY hard hitting bass. There has to be something I just am not getting yet.

This stuff is really starting to mess with my head. It was better when I didn't understand any of this. Now that I am learning it and trying to figure it out it makes my head hurt. There is a reason I didn't take electrical engineering and went structural.

Oh yea, thanks man.

[byers319]

you see where your head unit clips BEFORE seeing where your amp clips

the music on your cd's or whatever you so chose to use could be a clipped song, meaning everything after that clips as well

[RLB910]

you see where your head unit clips BEFORE seeing where your amp clips

the music on your cd's or whatever you so chose to use could be a clipped song, meaning everything after that clips as well

My HU does not clip. I turned it up to max, level 35, on both a 40hz tone 0db and 1000hz tone 0db. No clipping 5.4 volts comming out of a HU spec with 4 volt.

[byers319]

Well I'm not sure what the problem is then?

[Neo_frog]

I suggest trying to tune it with -3dB tone reference. Do the same process. Using 40-45hZ tone, turn up HU with flat everything, then turn up sub control until it clips off the RCA (amp side). BTW, I can't see pics so I don't know what kind of sub control you're talking about.

Tune the amp with the same tones on your reference volume. This may help you a bit, but not solve your problem. I've had similar problems in the past where tuning properly yielded almost nothing for bass. Sometimes with proper tuning, that's what you get though.

[SounDigital]

Tuning with an o-scope is a good practice, but we shouldn't be so worried about it, because this gain tuning is done without load. The problems start when you load the equipment down, playing music e.g. The battery voltage will drop and the amp's power supply internal voltage will drop, making the initial setting prone to generate clipping if you use the max level that was considered safe.

The only way to fix this is by using power resistors emulating the loudspeakers (or amps with clipping indicators).

That being said, I never worried too much about clipping, just build something able to play louder than you are willing to listen.

[cgrez33]

Tuning with an o-scope is a good practice, but we shouldn't be so worried about it, because this gain tuning is done without load. The problems start when you load the equipment down, playing music e.g. The battery voltage will drop and the amp's power supply internal voltage will drop, making the initial setting prone to generate clipping if you use the max level that was considered safe.

The only way to fix this is by using power resistors emulating the loudspeakers (or amps with clipping indicators).

That being said, I never worried too much about clipping, just build something able to play louder than you are willing to listen.

Haha Sound Digital is awesome

[kalilac619]

^^^^^^^^What he said!!Lol