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Sound Quality stereo install project

Not sure why but some of the pictures recently started showing that didn't before.

The place you are grounding your amps on the body is a bad grounding location.
If you notice in your pictures the body panel you are connected to is connected to the one below it by spot welding and sealed with seam sealer. That type of connection is a poor ground transmitter. You need to find a location that is either part of a continuous piece of metal connected to the firewall where there is a current main ground, the frame assuming the frame is grounded or run directly to the battery.

 
redheadedrod said:
Not sure why but some of the pictures recently started showing that didn't before.

The place you are grounding your amps on the body is a bad grounding location.
If you notice in your pictures the body panel you are connected to is connected to the one below it by spot welding and sealed with seam sealer. That type of connection is a poor ground transmitter. You need to find a location that is either part of a continuous piece of metal connected to the firewall where there is a current main ground, the frame assuming the frame is grounded or run directly to the battery.

I can't believe I missed that. Well back to the drawing board lol. I need to rework that back wall a bit anyway
 
gabrialm said:
So I finally got the midrange drivers and tweeters mounted in the truck. Was testing out the stereo and dialing in a base tune for time alignment, etc and noticed a serious alternator wine.
Grounding is likely your issue as Rod pointed out above, however, before you go pull everything and re-run new signal sources, you could try a simple ground loop isolater. I would still however find a better grounding location.
 
Calicak89 said:
Grounding is likely your issue as Rod pointed out above, however, before you go pull everything and re-run new signal sources, you could try a simple ground loop isolater. I would still however find a better grounding location.

I needed to change the rca situation anyway in advance of the new DSP. I'm confident that it's a grounding issue also, I'm going to ground to the rear bench bolt locations since its directly welded to the body etc. I'm pulling the old rcas now but I'm gonna try without pulling the rear bench and passenger front seat. well see how it goes.
 
If you look where the seat belts are, the driver side, middle belt has a nice open area to connect to. But you want to make sure any such connections actually connect to the frame if you are going to use them as a ground. The seat belt mounting locations NORMALLY have a connection to the frame somewhere. I know the front seats certainly do on my '03 as I just dealt with this on my truck after I drilled through the nut while trying to remove a bad bolt.
 
Calicak89 said:
Grounding is likely your issue as Rod pointed out above, however, before you go pull everything and re-run new signal sources, you could try a simple ground loop isolater. I would still however find a better grounding location.
Wow, I got completely overruled on that one ...
 
White Lightning said:
Wow, I got completely overruled on that one ...

lol, well I was gonna change up the RCA situation anyway after getting the new DSP. But I will be doing new grounds as well.
 
White Lightning said:
Wow, I got completely overruled on that one ...
Tunnel/driveshaft noise could be possible, but given that there was photographic evidence of a piss poor grounding location selection, I'm still leaning toward poor ground or a grounding loop.
 
Calicak89 said:
Tunnel/driveshaft noise could be possible, but given that there was photographic evidence of a piss poor grounding location selection, I'm still leaning toward poor ground or a grounding loop.

:laugh:

I'll accept that, lol. Waiting for the DSP and new RCAs to arrive, I'll get them ran/installed then fix the grounding situation. Then we'll see how much it improves.
 
I got the 4 ft length cables in from Amazon today that will go from the DSP to the amps, and two from the deck to the LC-1 for subwoofer level control. These are actually REALLY nice cables for the money. Just waiting for the 15 footers to get in and the DSP.
 
Got the 15 ft cables in from Amazon today, got them ran to the back. In the process I lifted up the passenger front carpet to route the cables along as far up and to the side as I could, and the underlay is soaking wet. :E:

It's either a backed up A/C drainage line or windshield seal. I doubt it's the windshield since we haven't had much rain lately, some about a week ago, but nothing recent. Top of the carpet is dry, so it's definitely something coming from underneath.

I've got the carpet propped up and the windows open to let it dry/air out so the truck doesn't get all musty. I'll have to look into it when I get some time. Going to be driving with the A/C and air blower off for awhile until I can troubleshoot.

The DSP should be arriving some time on Monday, so hopefully I'll get some time after work to get it installed after fixing the grounding situation and start with a baseline tune.
 
Got my DSP (Dayton Audio DSP-40:cool: and calibrated mic in finally (Mini DSP UMIK-1). Busy tomorrow, so Sunday is gonna be a fun day!
 
Finally had time yesterday to install the DSP and begin tuning. First time using REW, took a bit to get the hang of it.

Finished up the base tune of the front stage this morning. One thing I've learned?

BIG difference between pink noise calibration and what the mic pics up to make flat vs what the ear hears musically with actual content.

Ended up with the JBL house curve applied to all frequency bands for each driver. Attenuated the tweeters at -6 dB, the mid ranges at -3 dB and the mid bass -1.5 dB across the board.

It's still a bit harsh in the upper upper vocal range/cymbals etc, but I'm going to wait until getting the subwoofer installed to see how they blend with some actual bottom end before doing any more tweaking.



 
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