Menu
Forum
What's new
New posts
Live Activity
Search forums
Members
Registered members
Classifieds Member Feedback
Car Audio Discussion
General Car Audio
Car Audio Build Logs
Car Audio Equipment
Subwoofers
Speakers
Amplifiers
Head Units
Car Audio Help
Wiring, Electrical and Installation
Enclosure Design & Construction
Car Audio Classifieds
Car Audio Classifieds
Car Audio Wanted
Classifieds Member Feedback
Gallery
New media
New comments
Search media
SHOP
Shop Head Units
Shop Amplifiers
Shop Speakers
Shop Subwoofers
Shop eBay Car Audio
Log in / Join
Test
Forum
Search
Search titles only
Search titles only
Log in / Join
Search
Search titles only
Search titles only
What's new
New posts
Live Activity
Search forums
Members
Registered members
Classifieds Member Feedback
Menu
Reply to thread
Forum
Car Audio Help
Wiring, Electrical & Installation
Grounds ran to frame, swapped RCA cables, etc. Still noisy.
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Message
<blockquote data-quote="longbedbob" data-source="post: 8602473" data-attributes="member: 673854"><p>Good evening, folks.</p><p></p><p>I have a 2016 F150 that came with a base, factory stereo. I've installed a PAC dash kit and converted it to accept a double DIN with GPS.</p><p></p><p>I have also installed new speakers all around, two amps, and a sub.</p><p></p><p>Gear:</p><p></p><p>New head unit - Kenwood DNX693S</p><p></p><p>Primary Amp -Infinity Reference 704 A</p><p></p><p>Sub amp - Sound Ordnance 350-1 (hey, it's a truck. There's not much room behind the rear seat for a monster sub)</p><p></p><p>Despite my best efforts I have a few problems.</p><p></p><p>1. I have static through the door and dash speakers when the truck is turned off. No unusual sounds from the sub, though.</p><p></p><p>2. When the truck is running, I have alternator whine. Again, no whine heard through the sub.</p><p></p><p>Both sounds are base level noises that don't seem to get louder, only the pitch of the whine changes with RPM.</p><p></p><p>Prior to joining and writing this post, I have performed the following:</p><p></p><p>1. All wire to wire connections are soldered with heat shrink applied.</p><p></p><p>2. Power is running to both amps from the battery via 4 gauge wire, to a junction box under the hood, then through two 6 gauge wires- one for each amp. These wires are ran down the driver's side.</p><p></p><p>3. Moved grounds at both the head unit and amps. Finally routed 8 gauge wire for the rear amp and 10 gauge wiring for the head unit both through the front fire wall and rear of the cab directly to the frame. The frame was sanded prior to bolting the terminals. Both terminals were soldered and heat shrink applied to cover the terminal lugs and promote long term durability.</p><p></p><p>4. Resistance from the negative battery terminal to the head unit ground is .04 ohms. To the amp ground in the rear of the truck is .06 ohm. It's a long bed, supercab so there's a little more steel involved.</p><p></p><p>5. Voltage was 12.67 both at the rear of the head unit and at the amp.</p><p></p><p>6. Disconnecting the JL Audio RCA cables at the amp caused the sounds to disappear with no self induced noise. Disconnecting at the head unit did likewise. However, if I touch the head unit side of the disconnected RCA cables, I can get "body noise" which I guess is my body's electrical signal being amplified. They will also make a sound if the ends touch one another. Also, relocating and swapping out RCA cables doesn't eliminate the noises. RCA cables have been ran both down the passenger side or through the center of the cab.</p><p></p><p>7. Disconnecting the RCA cables from the amp and then connecting a classic iPod with mini RCA adapter provides clean output. No unusual noises and music is normal, either with the truck on or off.</p><p></p><p>8. Connecting temporary speakers to the speaker wire output of the head unit yields static.</p><p></p><p>So, at this point I'm thinking the problem is with the head unit or supplied power. The only inputs to the head unit are: constant 12V, switched, 12V, antenna, GPS (aftermarket), USB, PAC steering wheel control unit, reverse signal, and back up camera.</p><p></p><p>9. I've removed the CANBUS inputs and antenna one a time with no change.</p><p></p><p>10. Removing the constant 12 volt signal to the head unit and connecting it to the accessory power didn't produce any changes.</p><p></p><p>11. However, and this is the important bit....reconnecting the constant 12V to the factory harness but connecting the 12V switch power directly to the battery eliminated the static. The alternator whine was still there, but there was no noise whatsoever with the radio on and truck not running.</p><p></p><p>So, it seems that one of my noises is on the accessory power side of the head unit. I have two PAC 12V noise filters on the way and hope to install them tomorrow. I will connect one each to the constant 12V and switched power.</p><p></p><p>Anyway, I'm open to suggestions as to if I'm on the right track or if I should try something else.</p><p></p><p>FWIW, as a last resort I'm considering running a constant 12V from the battery and installing a relay to likewise get clean accessory power. I'm also open to swapping out the Infinity amp for a JL Audio RD line, which can handle unbalanced inputs.</p><p></p><p>Any feedback or ideas appreciated.</p><p></p><p>Thanks!</p></blockquote><p></p>
[QUOTE="longbedbob, post: 8602473, member: 673854"] Good evening, folks. I have a 2016 F150 that came with a base, factory stereo. I've installed a PAC dash kit and converted it to accept a double DIN with GPS. I have also installed new speakers all around, two amps, and a sub. Gear: New head unit - Kenwood DNX693S Primary Amp -Infinity Reference 704 A Sub amp - Sound Ordnance 350-1 (hey, it's a truck. There's not much room behind the rear seat for a monster sub) Despite my best efforts I have a few problems. 1. I have static through the door and dash speakers when the truck is turned off. No unusual sounds from the sub, though. 2. When the truck is running, I have alternator whine. Again, no whine heard through the sub. Both sounds are base level noises that don't seem to get louder, only the pitch of the whine changes with RPM. Prior to joining and writing this post, I have performed the following: 1. All wire to wire connections are soldered with heat shrink applied. 2. Power is running to both amps from the battery via 4 gauge wire, to a junction box under the hood, then through two 6 gauge wires- one for each amp. These wires are ran down the driver's side. 3. Moved grounds at both the head unit and amps. Finally routed 8 gauge wire for the rear amp and 10 gauge wiring for the head unit both through the front fire wall and rear of the cab directly to the frame. The frame was sanded prior to bolting the terminals. Both terminals were soldered and heat shrink applied to cover the terminal lugs and promote long term durability. 4. Resistance from the negative battery terminal to the head unit ground is .04 ohms. To the amp ground in the rear of the truck is .06 ohm. It's a long bed, supercab so there's a little more steel involved. 5. Voltage was 12.67 both at the rear of the head unit and at the amp. 6. Disconnecting the JL Audio RCA cables at the amp caused the sounds to disappear with no self induced noise. Disconnecting at the head unit did likewise. However, if I touch the head unit side of the disconnected RCA cables, I can get "body noise" which I guess is my body's electrical signal being amplified. They will also make a sound if the ends touch one another. Also, relocating and swapping out RCA cables doesn't eliminate the noises. RCA cables have been ran both down the passenger side or through the center of the cab. 7. Disconnecting the RCA cables from the amp and then connecting a classic iPod with mini RCA adapter provides clean output. No unusual noises and music is normal, either with the truck on or off. 8. Connecting temporary speakers to the speaker wire output of the head unit yields static. So, at this point I'm thinking the problem is with the head unit or supplied power. The only inputs to the head unit are: constant 12V, switched, 12V, antenna, GPS (aftermarket), USB, PAC steering wheel control unit, reverse signal, and back up camera. 9. I've removed the CANBUS inputs and antenna one a time with no change. 10. Removing the constant 12 volt signal to the head unit and connecting it to the accessory power didn't produce any changes. 11. However, and this is the important bit....reconnecting the constant 12V to the factory harness but connecting the 12V switch power directly to the battery eliminated the static. The alternator whine was still there, but there was no noise whatsoever with the radio on and truck not running. So, it seems that one of my noises is on the accessory power side of the head unit. I have two PAC 12V noise filters on the way and hope to install them tomorrow. I will connect one each to the constant 12V and switched power. Anyway, I'm open to suggestions as to if I'm on the right track or if I should try something else. FWIW, as a last resort I'm considering running a constant 12V from the battery and installing a relay to likewise get clean accessory power. I'm also open to swapping out the Infinity amp for a JL Audio RD line, which can handle unbalanced inputs. Any feedback or ideas appreciated. Thanks! [/QUOTE]
Insert quotes…
Verification
Post reply
Forum
Car Audio Help
Wiring, Electrical & Installation
Grounds ran to frame, swapped RCA cables, etc. Still noisy.
Top
Menu
Home
Refresh