Tech12volts 14 to 21 TUNDRA NON JBL ONLY CENTER CHANNEL

Does anyone know the ohm and watt rating for the rear door tweeter?

 

They are 4 ohm and 20 watt. Factory head unit puts out 4 x ~20w @ 4 ohms, rear tweeters, and then each dash corner wires to the center channel for a total of 4 x 20w.

 

Thanks Snert,

Do you know if the stock head unit/door speakers have any type of crossover in use?

 

From my disassembly I think the only thing I remember having a physical crossover in place is the center speaker. It has capacitors aka bass blockers hardwired to it. As for the rest of the speakers throughout, I don’t think there are any physical or passive crossover components, but I’m fairly confident the stock head unit has factory tuning to everything. I’ve read mixed things about the head unit sending out a flat signal to the door woofers.

 

The side dash speakers have caps on them as well.



I've heard the OEM amp sends lows and mids to the front door 6X9s..
The HU sends the amp the same signal it sends to the dash speakers..

 

Those audio system drawings seem to indicate model years 17 through 19. I wonder if my 20 is the same.

 

I have a ‘21 and I was just looking back at pics of my speakers and the dash corners have caps as well like @1lowlife said/referenced in his pics. I’m almost positive a ‘20 or ‘21 is wired the same because if the rear tweeters are 20w @ 4 ohms, and each dash corner speaker is 13w @ 6 ohms, wired in parallel to a voice coil of the center speaker which is dual voice coil 10w + 10w @ 8 ohms, that comes out to 3.43 ohms for each side of the dash and center, or roughly 23w @ 3.43 ohms and I’m guessing if speaker wire impedance was factored in it comes out to 20w @ 4 ohms for each side of the dash and center, which would make sense because that would match the power handling of the rear tweeters.

 

@1lowlife said

"I've heard the OEM amp sends lows and mids to the front door 6X9s..
The HU sends the amp the same signal it sends to the dash speakers.."

On my 2020, this is the question I would most like to know the answer to. Problem is I have no idea where to get that info from.

 

If the HU is sending the same signal to the dash corners/center, and the rear tweeters, and those all have in line high pass filters, my guess is that the OEM amp has built in low pass filters or even a band pass filter that keeps them playing below a certain frequency, or in a certain frequency range. It could also be that the HU is sending out a processed signal to the amp and the amp is just increasing its power.

The only way to effectively figure this out would be to either set up a mic and REW and test all the speakers independently, or get something like an iRTA from 5 Star Car Stereo and test/record the outputs. I don't know that anyone has gone that in depth on testing the frequency responses of the factory system.

Anecdotally though, I know that both people on the forum, and the Tunes from Tacos people use one form or another of a line output converter with bass restoration, or a dsp, to correct the factory bass lacking from the system. Since those line output converters are wired in pre-amp, I guess I'd think more so that the head unit is sending out a processed pre-amp signal. One super basic way to determine if the head unit is sending out the signal processed pre-amp, or if the amp has built in filters, would be to connect a subwoofer both pre and post amp and compare the response by ear.

 

Yes I have been thinking about hooking up a speaker pre and post under seat amplifier. That may be the only way I can confidently conclude the functionality of the head unit output signal.

That is a lot of BS I'd really rather not go through. Fortunately, I'm not in a hurry and maybe by the time I decide on my end game as far my truck audio goes I'll have the answer.

 

I would bet on this scenario. The OEM amp is filtering and or adding DSP to those drivers. Just a hunch

 

I agree, this seems the most likely scenario. If this is the case the

$129 AudioControl LC7i 6-Channel Line Output Converter with AccuBASS

AudioControl LC7i wouldn't be needed, just an amplifier.

 

From the TT website:


"Ntune" is their version of a LOC with bass boost. In 2020/2021 I believe that's when they did the Entune upgrade and changed some stuff in the trucks. If they're saying that their "Ntune6" is required in a 2020/2021 truck, I think it would then track that the head unit is sending out a pre-amp processed signal, and the head unit is doing the filtering not the amp, since the Ntune6 would wire in just like an LC7i on the pre-amp side. Them saying it's not required for 2007-2019 makes me think that in those years there's physical components in the amp itself creating filters, rather than the head unit sending out a filtered signal, and in 2020/2021 with the Entune update they updated hardware, software or both in the head unit to give it some dsp-esque functionality.

 

Received the center and have been using it for a couple of weeks. Ok, first off this made a huge difference in the high frequency sound reproduction. Overall I like it even though it's a bit on the bright side, I'm still working with it and just yesterday I had an idea. I took a Kleenex and separated the two plies, then placed a single plie over the two tweeters. I haven't secured the center cover down yet so just lift it, add Kleenex and set it down, this seems to be a positive addition taming the bright edge for a bit of warmth.

James (tech/12) included pigtails off the new center, to wire in a subwoofer. I have already started buying my parts to add a sub, so in a couple weeks I should have a sub added to the system.

After living with this setup, I'll decide if phase three is needed. I'm hoping this will be good enough so I can avoid additional spending.

 

I am in the process of adding a subwoofer to my truck. While the under-passenger seat amplifier was disconnected, I wired one voice coil side of my stock center channel speaker to the head unit LF (out to amplifier) disconnected plug.

Turned the radio on and I heard what sounded exactly the same as what the dash speakers were playing. This would seem to indicate that the head unit is sending a full range signal to the under-seat amplifier, with the amplifier providing a processed signal to the door speakers. However, it does not prove anything as far as bass response is concerned.