Thoughts on AWFUL hissing with LC7i???

Hey guys.

So today I had my local shop install an LC7i along with a JL Audio XD500/3v2 and a pair of Focal PS165FX speakers, and the hissing coming out of the speakers at ALL volume levels is absurd! Even with the head unit powered off there is still a hissing noise.

My shop said it's because the Bluetooth in the factory head unit never shuts off, and there is nothing they can do, but that was the whole reason I went with a high-end LOC like the LC7i instead of just a cheese-ball LOC.

The shop I had do the work is the best shop in town and they do tons of high-end sh*t, so I know they did the install right, but I'm super pissed right now cuz all this stuff was NOT cheap.

Can anyone offer any help to get rid of this damn hissing? (besides the smart ass answer of "replace the factory head unit" cuz I don't want to!)

Thanks!

 

I doubt that the bluetooth has anything to do with it, to be honest...

Troubleshooting signal interference with aftermarket integration is always a crapshoot. Where is everything that was installed located?

 

Yeah. I turned the BT off on the headunit and hissing was still there.

The amp is under the driver seat and the LC7i is under the passenger seat. Was thinking maybe the ground for the amp was crap but like I said, this shop knows what they're doing, so you'd think they'd know how to ground my amp properly.

 

You could try adding resistors to the speaker wires between the LC7i and the head unit to emulate factory speaker resistance but that might not do anything. Like I said, troubleshooting this stuff is always a crapshoot. The most effective solution would probably be to control the total system volume with an Audio Control level control knob hooked up to the LC7i. That should make it so that the hiss will be less noticeable at low volumes.

 

I have tried both the audio control as well as a JL cleansweep in my other car and could never get rid of the hiss. The cleansweep was a bit better regarding the level of hiss, but it was still present. You can chase cures forever and not find it. Might try to add an inline noise filter on the rca's. Those are cheap, quick, and easy to try. Only real fix though is to go aftermarket HU.

 

Damn.

Well on that advise I went ahead and ordered up a Pioneer DEH-80PRS from Crutchfield.

One of the main reasons I wanted to keep the factory head unit was because I really like the touchscreen, and none of the big brands seem to be focused on sound quality with their touchscreen head units. All they care about is bells and whistles.

So instead, I went with the baddest mamma-jamma of a single-din head unit around. Well, excluding the Pioneer Stage 4 head unit, but that thing is stupid expensive, and the DEH-80PRS has a lot of the same tech in a MUCH more affordable package.

Anyone wanna buy a 2 day old LC7i?

 

Maybe see if you can exchange it for an Audio Control equalizer? Having that kind of tuning control can really do wonders for your stereo.

 

The DEH-80PRS already has some pretty killer DSP and tuning capabilities so I'll think I'll be good with just that for now.

 

How much for the lc7i?

 

I paid $190 shipped from Crutchfield, so I'd go maybe $150 shipped to the lower 48?

 

I'm in the almost EXACT same boat with the stock head unit. I even went with the ground loop isolator, didn't change a thing. I don't mind going aftermarket but would want to use the stock mic for the phone. Were you able to do that?

 

Don't think anyone makes an adapter for that, but I'm sure it can be done. Just have to splice into the wires for the factory mic. Why would you want to though? Almost every single aftermarket mic is gonna blow the shitty factory mic out of the water.

 

Are your PA165Fxs in the front door? If so, what adapter did you use to get them to fit?

 

As an installer myself, in a town with lots of audio shops, I've seen some AWFUL work come out of ALL of them at some point in time.

I also find it very hard to believe that the bluetooth in the head unit "stays on" because this would keep pulling power. Even at low draws, that would kill the battery after just a few days of sitting still.
I also don't know if if I believe this because toyota radios are very basic in their power systems. They all have a 12v accy wire in the harness which means the radio is either on or off.

Hiss typically comes from bad grounds, or gains set too high. I've seen lots of shops have a bad habit of setting gains way too high. It's easy to do without the right equipment.

 

Turn your gains down

 

Fresh system came into the shop with a heavy hiss, gain was set too high on the LC6i. Turning it down fixed the hissing issue.

Side note: 4ch amp was set with fader on, so the front door speakers were about 60% quieter than the rears.

 

https://www.tacomaworld.com/threads...iocontrol-lc7i-*********-jbl-amp-comp.585730/

I haven't had a hiss issue with my setup. I did get a harness from ********* and did not have to splice or cut any wiring.