Featured Tweeter buzzing/noise insanity

Ezzy4Vibes

CarAudio.com Newbie
Quick run down on install
2019 Mustang GT base 4.2" sync radio/ non-amplified Stock

Installed:
Pioneer C2550NEX headunit
Maestro RR (steering controls)
Hertz K165 speakers component front /coaxial rear
- Uses inline crossover capacitor
Sky High Audio Triple shielded OFC RCAs (4ch & mono)
Recoil OFC 9 wire (speed wire)
Sky high OFC 8 gauge to 4ch amp
Down 4 sound MM504 50w x4 rms 4ch amp
Taramp Smart 3k RMS mono
Deaf Bonce 272s 12" x2 subs
JS 320A alternator w/ 14.8 regulator
Sky high 1/0 OFC oversize power wire, battery to rear
Big 3 with 1/0 OFC
2.5F power capacitor (yes I know they're useless)
+ ALL speaker connections are soldered and shrinked wrapped, no crimps

I get a high pitch buzz from the front tweeters constantly unless radio is off. And mids/highs cut out at loud volume/bass (see below).

attempted...
+ RCAs/speed wire ran on left side /power on right side of vehicle
+ Disconnected RCAs at HU and at amp: no difference
+ Regrounded amps (main ground is 1/0), verified at .00-.01 ohm from battery: No difference.
- Amp direct to chassis gnd
+ Individually grounded each RCA jacket with a jumper wire: no difference
+ Turned amp gain 0-100%: No difference
+ Disconnected sub amp: No difference
+ Tested speaker continuity, all 4 ohms at amp
+ Disconnected microphone to HU: nothing
+ Disconnected rear view camera: nothing
+ Tested each RCA continuity end to end: all show 1.5 ohms
+ Engine RPM makes no difference

This leaves me with only the amp, amp turn on wire (comes from Maestro radio harness) or the tweeters themselves. The rear coaxials do not put out noise.
What's strange is when I go over bumps in the road or when the bass is really high (running 3k RMS) at 1/2-3/4 volume the noise will get louder or quieter AND the mids/highs will cut out periodically. This leaves me with suspicion that the amp is at fault. After all it is a $115 amp from Down 4 sound. Or the tweeters are cheap despite it being Hertz.

The only things that make the noise stop:
+ If I touch the tweeter positive and negative exposed wires together at solder joint, it stops (with no music playing at 0 volume). Obviously this shorts the tweeters but also indicates static from somewhere
...shaking these wires makes no difference, it's only when exposed copper touchers each other

+ If head unit is switched off, it stops. As soon as I turn it on for radio or any other audio input the noise immediately starts. This is with the RCA disconnect so technically the only thing powering speakers is the amp


Any ideas?
20241003_183128.jpg
 
Last edited:
I get a high pitch buzz from the front tweeters constantly unless radio is off. And mids/highs cut out at loud volume/bass (see below).
From a whine or whatever to amp recommendations for Skar Evl's?

Where in the FB space is THIS thread headed?

Op... one solution at a time please.

I got to say it... pics or bs...

"brandon pinchett" has apparently invaded your thread and I didn't catch it before replying. Someone should... haha. But asking for sub amp recommendations on anothers thread?

I have NO solutions to Op's book he wrote, I'm focused on "Brandon" initially in my reply.

"Brandon" next time start your own thread man.

No hate, just reach out if you'd like assistance. Your own thread gets responses focused on your question.

Evl-15s? I may remember those...

This forum reeks experience.
 
Last edited:
Amps are grounded separately. I set gain at 3/4 tilt before clipping, at 0 gain the noise is there.

As another said, I will check amp to tweeter wiring for issues.
Since it is a 4 channel, swap fronts to back including the RCAs to see what happens. If the sound moves back, it will be the amp.
If sound continues, try bridging the amp.
 
Last edited:
Amps are grounded separately. I set gain at 3/4 tilt before clipping, at 0 gain the noise is there.

As another said, I will check amp to tweeter wiring for issues.
That is way too much gain. You shouldn't even be near half with a pioneer head unit and your amps should be grounded together to avoid ground loops.
 
I reset my gains using an oscilloscope making sure there is no clipping. Then switched RCAs and speaker connections to opposite and the noise is still there.

Then disconnected RCAs, speaker wires and tested the amp with my oscilloscope. I found a constant 2-4k hz noise signal on the speaker outputs. Strange.
Checked 12v+, negative and rem turn-on input= silent.
Basically the amp is sending a constant noise signal.
The nearby mono amp, capacitor and main ground were silent without this signal. 4ch and mono share the same power and ground supply.

Another test I did was tapping on the amp and a change noise volume can be heard from the tweeters.

I checked all wiring from amp to tweeter and it tested good. Wires were silent on oscilloscope when disconnected.

At this point I'm condoning the amp itself and will get a different 4 ch to test.
 
Last edited:
I reset my gains using an oscilloscope making sure there is no clipping. Then switched RCAs and speaker connections to opposite and the noise is still there.

Then disconnected RCAs, speaker wires and tested the amp with my oscilloscope. I found a constant 2-4k hz noise signal on the speaker outputs. Strange.
Checked 12v+, negative and rem turn-on input= silent.
Basically the amp is sending a constant noise signal.
The nearby mono amp, capacitor and main ground were silent without this signal. 4ch and mono share the same power and ground supply.

Another test I did was tapping on the amp and a change noise volume can be heard from the tweeters.

I checked all wiring from amp to tweeter and it tested good. Wires were silent on oscilloscope when disconnected.

At this point I'm condoning the amp itself and will get a different 4 ch to test.
Yea.. you couldn't pay me enough to run d4s gear. Sketchy asf imo.
 
Activity
No one is currently typing a reply...

About this thread

Ezzy4Vibes

CarAudio.com Newbie
Thread starter
Ezzy4Vibes
Joined
Location
United States
Start date
Participants
Who Replied
Replies
11
Views
911
Last reply date
Last reply from
mahc
IMG_1882.jpeg

slater

    Oct 4, 2025
  • 0
  • 0
Screenshot_20251004_120904_Photo Translator.jpg

1aespinoza

    Oct 4, 2025
  • 0
  • 0

New threads

Top