Extreme bass on some songs

[Mast0rMason_]

So I've connected a line converter to a MK7 fiesta stock radio. On some songs the bass is extremely high, like the rare song. But I've tested a few and it seems like something to do with the stereo increasing bass when not many other frequencies are playing. If the volume is on 2/30 the bass is loud, but on another song to hear the bass as a sub should perform I've set it to 20/30. On these certain songs the volume needs to be around 6/20 to achieve the same levels as every other song at 20/30.

Here's the funny thing, I've tried using a tone generator to play and cycled between 20-120hz and it didn't do it.

What could I do to diagnose what the issue could be? Could it be a power surge with a dodgy ground at all?

 

[spokey9]

Could be getting peaky at the fs of your car (my car gets real loud around 55-60-hz) or it could be the level the songs were recorded at (ie -6db or 0db whatever the case).

I adjust my subs from when I need to from track to track

 

[SHO'NUFF]

So I've connected a line converter to a MK7 fiesta stock radio. On some songs the bass is extremely high, like the rare song. But I've tested a few and it seems like something to do with the stereo increasing bass when not many other frequencies are playing. If the volume is on 2/30 the bass is loud, but on another song to hear the bass as a sub should perform I've set it to 20/30. On these certain songs the volume needs to be around 6/20 to achieve the same levels as every other song at 20/30.

Here's the funny thing, I've tried using a tone generator to play and cycled between 20-120hz and it didn't do it.

What could I do to diagnose what the issue could be? Could it be a power surge with a dodgy ground at all?

Audio control had seminars about this when factory heads started incorporating all kinds of controls and getting a new head unit quit making sense.

What they found at the time was that most factory heads would manipulate the lower frequencies with the volume, and amplifying that signal would exaggerate the effect.

I would leave the factory volume at maybe half, or 2/3rds, and set your eq to it, then use a remote volume knob to control the volume.

Make sure your head is in stereo mode, some factory 'surround' settings do dumb things.

Just some thoughts.

 

[Mast0rMason_]

Audio control had seminars about this when factory heads started incorporating all kinds of controls and getting a new head unit quit making sense.

What they found at the time was that most factory heads would manipulate the lower frequencies with the volume, and amplifying that signal would exaggerate the effect.

I would leave the factory volume at maybe half, or 2/3rds, and set your eq to it, then use a remote volume knob to control the volume.

Make sure your head is in stereo mode, some factory 'surround' settings do dumb things.

Just some thoughts.

If I leave the volume on 2/3 and a song that does this plays it happens mid song it will blow the hell out of it. There's a DSP occupancy to optimise for driver or all passengers but I've set it to all. Only 3 eq settings on factory stereo of bass mid and treble, all are default and set to 0 (ranges -7 to 7, roughly).

Been brainstorming since writing the thread, worst comes to worst I'll have to check the voltage of the stereo speaker output.

Tomorrow I'll test the RCA cable voltage and ground resistance, accidently left my multimeter on so I need to grab a 9v battery.

I don't suppose it could also be that I've used 2x 8gauge wires for a ground rather than 1x 4 gauge could it? Could only grab what I could find as I don't have a set of crimps large enough to buy new wires and terminals.

 

[SHO'NUFF]

If I leave the volume on 2/3 and a song that does this plays it happens mid song it will blow the hell out of it. There's a DSP occupancy to optimise for driver or all passengers but I've set it to all. Only 3 eq settings on factory stereo of bass mid and treble, all are default and set to 0 (ranges -7 to 7, roughly).

Been brainstorming since writing the thread, worst comes to worst I'll have to check the voltage of the stereo speaker output.

Tomorrow I'll test the RCA cable voltage and ground resistance, accidently left my multimeter on so I need to grab a 9v battery.

I don't suppose it could also be that I've used 2x 8gauge wires for a ground rather than 1x 4 gauge could it? Could only grab what I could find as I don't have a set of crimps large enough to buy new wires and terminals.

That's strange that it would happen mid song without touching the volume. Does it happen mid song if you're listening to a CD? No Bluetooth or radio.

Ground sounds fine, as long as it's solid, tight, no loose connection.

Maybe leave the stereo on and see if you can replicate the problem by turning wires and snugging up connections. A pinched RCA can do that.

 

[1aespinoza]

Here's the funny thing, I've tried using a tone generator to play and cycled between 20-120hz and it didn't do it.

I would assume it is the radio's built in eq curves that are meant to protect the OEM speakers.
You will need a DSP with signal leveler. That should solve the issue.