3rd Gen Speaker Output Signals

Lancejoker · Sep 23, 2021

Does anyone know what the voltage is on the 3rd Gen non JBL speaker outputs?

dolbytone · Sep 23, 2021

This is from a 2020 4Runner but probably it’s very close to what is the case in a Tacoma as well.

https://www.tacomaworld.com/threads/2020-entune-factory-integration.691221/#post-24505957

dolbytone said: ↑

Alright so there are times when you wanna know when your stereo starts clipping, usually this happens automatically when you have one of those new fangled amplifiers and it gives you lights and shit and you don't know what's going on but you do know GREEN = GOOD! So, I'm here to show what's happening to the signal, but also to figure out where the factory radio begins to distort. Interestingly, and annoyingly each channel begins to clip at 24.7V but the fader is slightly different for each channel when it reaches this voltage... You may or may not care, but generally, aftermarket stereos can reach full volume and not send a distorted signal. Nice ones anyway.

I put on the 1KHz sine wave and with the speakers disconnected, I connected my oscilloscope to the amplifier input connector for each channel and checked the fader setting when each begins to square off.

This is what a 1KHz tone looks like with no clipping.

This is what a 1KHz sine looks like just as clipping begins, note the slight square shape of the wave at max amplitude.

And here it's just damn obvious the wave is square and definitely distorted.

Here's the list of fader settings for each channel where the signal just begins to clip, one notch down and no clipping occurs.

Front Left - Fader 55
Front Right - Fader 49
Rear Left - Fader 52
Rear Right - Fader 51

I guess the only explanation for these differences is that the output is attenuated for the driver position, or some position anyway, as the right side of the vehicle reaches voltage sooner than the left side, and the driver front reaches voltage last which makes sense, being the closest set of speakers to the driver's seat.

I'm working on getting the signal on my RTA but shit isn't cooperating and I wasn't able to get any measurements tonight. I wanted to see the pink noise response for each channel as it comes out of the factory stereo. I'll keep screwing around with it but I'm not sure if I can get anything useable with the stuff I have on hand. I might need to bust out the mega-kit.
Click to expand...

This weekend I will probably take the same measurements from a 2017 4Runner and I can update with what I find.

destin_meeks · Sep 23, 2021

Here’s some extremely basic testing I did a while back. Nothing fancy, nothing crazy, but got the job done

https://www.tacomaworld.com/threads/3rd-gen-entune-premium-head-unit-specs.623113/

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3rd Gen Speaker Output Signals

#1
Lancejoker [OP] Well-Known Member

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dolbytone Well-Known Member

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destin_meeks I used to fix people's crappy stereos

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3rd Gen Speaker Output Signals

#1 Lancejoker [OP] Well-Known Member

#2 dolbytone Well-Known Member

#3 destin_meeks I used to fix people's crappy stereos

Products Discussed in Entire Site Forum: Audio & Video

#1
Lancejoker [OP] Well-Known Member

#2
dolbytone Well-Known Member

#3
destin_meeks I used to fix people's crappy stereos

Products Discussed in