Blown speakers/head unit?

[Jonas84]

So put in 2x12 in my bmw e61lci Touring and started cranking, up to 75% to not get distortion.

After a few weeks all my speakers "door, roof" sounds blown, distortion on low level.

If i disconnect the 2x12 subs and underseat subs "both driven by separate amps" , does no difference.

Put in new musway esc4. 2 speakers. Sounds the same.

Is my head unit blown? If so why.

Dont know what to try, tested left/front vs rear. All sound distorted, trashed and there brand new, plqyed a few seconds.

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[CarAudio.com - Hal AI Bots]

So put in 2x12 in my bmw e61lci Touring and started cranking, up to 75% to not get distortion.

After a few weeks all my speakers "door, roof" sounds blown, distortion on low level.

If i disconnect the 2x12 subs and underseat subs "both driven by separate amps" , does no difference.

Put in new musway esc4. 2 speakers. Sounds the same.

Is my head unit blown? If so why.

Dont know what to try, tested left/front vs rear. All sound distorted, trashed and there brand new, plqyed a few seconds.

It sounds like you're experiencing some significant audio distortion issues. Let's troubleshoot together. Can you clarify if the head unit is functioning properly and if it's receiving a clean signal?

 

[5t4y_50L0]

I'd check battery voltage, head units functionality and lastly signal. Could have a wire touching metal or just loose RCA... Idk your HU make, are using an LOC ?

 

[Jonas84]

Head unit is oem ccc for bmw e61Lci and is working in all ways, signal i cant say, my oscilloscope will arrive next week.

But as said, it sounds like bad signal.. Distortion even on low for the speakers connected to the HU.

No LOC, since this is hifi 676 option it has low ground to the oem amp in back, which i discarded and now run a amp for the subs with 4 gauges wires. That then sends signal to next amp with 0 gauge wires to the 12" subs.

Battery is brand new 105ah 950cc agm varta, and i dont believe power is the culprite, it chargs and maintain voltage, and i said. Doesnt matter if i disconnect the amps power/signal.

It became like this after i used 0db test tone to set subs, atleast i believe.

And since i put in new door speakers today and the still sound crap. Im sure its not that.

I use firefly ldac as bluetooth source, tried settings in spotify, android, oem hud. Doesnt matter if i take away bass"makes less noticable do" or change eq settings.

So im thinking about buying vibe powerbox dsp to run doors and rca signal to amps.

Any thougts?

 

[Jonas84]

https://vibeaudio.co.uk/product/powerbox80-6dsp-v3-vibe-powerbox-80-6-dsp-4-channel-car-audio-amplifier

 

[huberoy123 10+ year member]

I would thoroughly test the head unit, before I spent money on anything else. Let us know the results.

 

[Jonas84]

Guess only thing i could do is test the signal thrue any of the door speakers with a oscilloscope i guess, and see if it distorts from low level, something is off for sure.

A dsp is on my list to control everything with one device.

Changing Hu is a bit of gamble since the chinese Android versions rarerly has any spec.

 

[Jonas84]

Guys i need your help, recently started this hobby again, and im a bit lost.

How do i messure with the oscilloscope to test it, hz, volume etc.

I also got curious if the outputs is low level as told. They are wired so i soldered and connected rca. When doing the high signal to amp it wouldnt even start. Also read a low level will give contuinity? Aswell it wont play a speaker. Connected a tweeter and there was no sound, but no ground either. Is there a sure way to test it?

I hooked up the oscilloscope to rca, played 80hz and could do it all the way without seeing a single flat line, didnt have time to test on high level speaker wire.

The speakers sounds like they tremble on any high or low pitch"bass" flatting out. Ive played these songs before and no problem. Disconnected signal to amps, no change.

Any voltage i should messure and how.

Im out of my comfortzone for sure... Maybe the dsp/amp combo could help

 

[1aespinoza 10+ year member]

I also got curious if the outputs is low level as told. They are wired so i soldered and connected rca. When doing the high signal to amp it wouldnt even start. Also read a low level will give contuinity? Aswell it wont play a speaker. Connected a tweeter and there was no sound, but no ground either. Is there a sure way to test it?

Is there a way to connect a different audio source to the amps? For testing we usually use the phone direct to any amplifier via 3.5mm to RCA patch cable. That way we verify if the amp is the issue or signal source.

 

[highfigh]

So put in 2x12 in my bmw e61lci Touring and started cranking, up to 75% to not get distortion.

After a few weeks all my speakers "door, roof" sounds blown, distortion on low level.

If i disconnect the 2x12 subs and underseat subs "both driven by separate amps" , does no difference.

Put in new musway esc4. 2 speakers. Sounds the same.

Is my head unit blown? If so why.

Dont know what to try, tested left/front vs rear. All sound distorted, trashed and there brand new, plqyed a few seconds.

If you need to crank the volume control to anywhere near 75%, you need more power. Head unit power ratings have always been optimistic and ALL of them will distort near 75% volume control setting, in whole numbers of THD.

Why is the amp in your head unit blown? Heat- that's what kills all output devices.

 

[shredder1 10+ year member]

I also got curious if the outputs is low level as told. They are wired so i soldered and connected rca.

Maybe a language barrier, but it sounds like you soldered some female rca ends onto what you were assuming to be low level outputs, then ran your rca's back to the amps?

I'm unfamiliar with your factory hu but what you did sounds... Suspect.

 

[Mitchell Fosgate III Untrusted Member!]

It’s probably because when you changed the speakers in your BMW, you threw out the electrical system they had calibrated to the car power system. Now every thing is off. Volts, ampere, and resistance, for the speakers and radio. And amplifier. All of these was measured. To make it run good. Now it’s not good because you’ve changed it to whatever.

The BMW features are for smooth running car and power rating. The music came secondly. Now it is off base. You’ll have to measure it again to get it close to it or correct settings. The volts, ampere, and ohms. Good luck to finding it.​

 

[Jonas84]

Yes i soldered on rca, the wires usually goes thrue a connector to the oem amp.

Offc i can test the amps with another signal. But the amps only drive subwoofers.

The sound was good at first in door speakers, driven by HU. I changed them since i believed they were blown. Still sound the same.

So the problem seem to be at the built in amp in Hu. Doesnt matter if i disconnect the amps signal or power.

And if you listen closely it sounds bad even on lower volume sometimes.

A combined dsp/amp should fix it?

 

[shredder1 10+ year member]

Yes i soldered on rca, the wires usually goes thrue a connector to the oem amp.

A combined dsp/amp should fix it?

I'm unsure anything other than replacing the hu with a quality aftermarket one is going to be the solution. You replaced the speakers, installed amp/subs already so if it was my vehicle I'd just bite the bullet and install something with legit low level outputs.
And not some janky Chinese android one either. A quality clean source is super important.

 

[Jonas84]

Cant find one for the e61 lci, all are dodgy chinese Android.

But a dsp with bluetooth would send clean signals and give outputs to the rca as i understand.

Most dsp with built in amp dont even need HU, but i want it for the built in handsfree and control sound thrue steering wheel.