4 Channel EQ?

I would like to put a passive EQ on my factory Toyota head unit but it has 4 channels. All of the EQ's I've seen are two-channel but have a fader control. How would I wire up a factory HU with separate grounds for each channel?

Would I have to utilize the EQ's fader control for my fron/back control?

Thanx,

Bud

You want to add 4-channels of EQ to your factory HU?  Well first you'll have to find one that will accept speaker-level inputs, and then if it's 2-channel, buy two of them (one for front, one for rear.)

No sale for you. An EQ is looked at one of two ways. First way that most people look at it is how you have (no offence intended, learn from it as others will as well). In this case it is a band aid. The second way to look at it is to solve an identified problem after all other avenues have been exhausted. Proper equipment with proper installation will take care of 95% of issues related to sound. If you need a band aid to make something sound better, then you have inherent and drastic flaws in the system design and installation. A EQ for the most part is also a breeding ground for noise and clipping due to it's manipulation of the audio signal. Now, if you have a system installed and operating to the best of it's abilities and you find that you have a monster midbass hump at 200 hz that is making the midbass overpronounced, then a EQ may be used to specifically tame that monster.

Always look at your signal as garbage in, garbage out. If you have a poor head unit with a poor output, then try and correct it with an EQ, sending a signal to a incorrectly set amp and incorrectly mounted and inferior speakers, well I'm sure you get the picture here. Post what you have for a system or what you are considering for a system before you go on the path of wanton destruction. There are quite a few people on the site that may have the same questions as you and there are some great people on this site that can answer them properly. I just happened to have a little time free this morning / afternoon, however my free time window is closing rapidly here.