2024 head end unit question

Hi all. I will be buying a 2024 soon without the JBL system. My question is about the stock head end unit. I do not want to replace it. However, I have read that it does not put out a full-range frequency response, deliberately removing or demphasizing low frequencies from the back door and tailgate speakers. I also have read that it has significant "equalization" curves built into it. Those things are not good. Can anyone confirm or disprove this on the 2024 or at least the 2023 stock head end unit? If true, has anyone measured the output frequency response to see exactly what the output is?

I have a very hard time believing that there is anything special going on in the head end unit that actually does this equalization or rolloff, and I suspect it may be due to simply having awful factory speakers. The install videos for the Kicker and OEM Audio speaker sets make no mention of this issue, and it seems like they would not sound very good if any of this were true, yet people like both of those upgrades very much.

In my FJ Cruiser, a head end unit "feature" called ASL (Automatic Sound Leveling I think) can be turned off. It's sort of like a loudness control. With that disabled in the head end unit, which was made by Pioneer according to the sticker on it, and a decent power wire run to it, it actually works pretty well, and it's still in there after 13 years.

 

You need something like this to restore the full audio spectrum and provide proper line out voltage. This couples perfectly with the OEM head unit and works in conjunction with an after market amplifier.

Corrected link: https://www.audiocontrol.com/car-audio/factory-system-upgrade/lcq-1/

 

This will probably draw some flak, but my biggest issue with sound quality on the '23 ORP is the dash speakers. Yes, the EQ curves aren't what I'd like them to be, nor is the frequency response, but I relieved some frustration just by tweaking the faders more to the rear. I might do something more dramatic (and costly) in the long run, but I'm likely to upgrade speakers and do some impedance matching and signal conditioning rather than ditching the head unit.

 

lol 4r is not a good baseline to be concerned with those nuanced audio qualities….

 

Get the ds18 plug n play speakers… got them off eBay. Better than the Subaru kicker alternative

 

Trying to keep the stock head unit is a terrible rabbit hole to go down. I wasted so much time and money trying to keep it, just not a good way to go if you looking for high quality sound.

I ended up replacing the head unit, sooooo good now.

 

I'm not looking for high quality sound, just sound that doesn't piss me off.

 

You running all stock?

then get these..https://www.ebay.com/itm/304191991655

 

I am so far, but I'm taking those under consideration.

 

These are again just tweeters. Hardly any upgrade. What one actually needs is a full 3.5 inch speaker with capacitors. That will bring in the most upgrade from the dash speakers.

 

This is a huge upgrade from the stock tweeters.

rule of diminishing return applies to audio equipment.
I say these aftermarket speakers represent an 85% improvement from oem.

 

Stock tweeter is so bad it's hardly a yardstick. And you are still replacing a tweeter with a tweeter.
A tweeter is no match for a full range 3.5 inch speaker in the dash.
I have heard this tweeter. It improved a little on clarity but it was still thin sounding, was shrill and did nothing for vocals. What just a tweeter would do.
Now if you ran a 3.5 and cut the lower frequency with a capacitor, you gain clarity as well as vocals from the dash speakers.

 

That's the tradeoff I've been thinking about. There are some decent drop-in tweeter-only options, but it looks like most wider-bandwidth options need some installation adaptations.

 

Pick any 3.5 inch from JBl, Infinity, kicker etc. They drop right in. You can actually modify the OEM brackets to fit them. They all come with capacitors. Best upgrade you can do to the dash speakers without breaking the bank or any modifications. Everything is plug and play

 

Interesting….

 

That was my plan too. $4000+ later I am happy.

The key to overall sound in our 4R's is the front 6x9 door speakers. Try replacing the front door speakers first, maybe component 6x9's with tweeters if possible.

 

I'm likely to do that eventually as well (the door speakers, not the $4k).

 

I'm not really interested in the speakers right now. I will use the same approach that I used in the FJ Cruiser. I will not be using the typical solutions.

What I am interested in is whether anyone can prove that the output of the 2024/2023 head end unit has some sort of roll off or built-in equalization and if so, the exact values. In other words, outputs applied to an analyzer on a test bench, not in-truck measurements using speakers. Everyone said this about the head end unit in the FJ Cruiser, and it all turned out to be false. It has a feture called ASL that works sort of like a loudness control. It is variable and can be turned off. It actually works OK, but I ended up leaving it off.

That's what everyone said about the FJ Cruiser until I reengineered the system. It has been sounding great for 13 years now. Yes, I am an audiophile, the type who builds his own amplifiers and designs speaker systems and acoustic room treatments. If I like the stock head end unit in the FJ Cruiser, rest assured it is just fine when used properly.

 

Just go to Crutchfield and get a set of 6x9's for the front door and a set of tweeter replacements for the dash. You may be satisfied with that alon if you aren't looking for anything high end.

 

lc1i 2 channel line out converter and line driver

It doesn't mention anything about restoring an altered output frequency spectrum allegedly built-in to the head end unit. I doubt these rumors about the head end unit are true. It's probably an ordinary head end unit without any frequency-altering characteristics built into it. The JBL unit might, but I doubt it for the non-JBL. I'd like to see proof on a test bench, not in-truck response using speakers.

 

You really putting the cart before the horse. For most folks, they either swap out the head unit and build from there or add a DSP/amp to the stock head unit and go from there. The rest just swap the speakers running the stock head unit and are satisfied.
If you have decided to buy a 4runner, the information you seek should be available to you once you take delivery and spend time with the head unit.
Now, if your buying decision is predicated on how good the head unit is, that's a different thing.

 

I meant to link the LCQ1. If you believe the OEM head unit doesn't alter frequency then go with that. I wish you luck.

 

If I can't find proof, I'll test it myself. It proved to be totally false in the FJ Cruiser.

No, engineering an audio system has to be done from the ground up to be done properly and that is exactly where I am - engineering phase. I don't need the truck in my possession to do that. First step is to find out if any "correction" has been applied to the output of the stock head end unit. I seriously doubt it. The JBL system probably does as they are known to try to tune their system to produce a desired result. The non-JBL system is probably just a low-power 4 channel internal amp like any other.

I did note that the head end unit has a fan, just like the one in my FJ Cruiser. As I said, it's quite good when used properly. One key to success with that one was running a power wire from the battery directly to the head end unit. Most people never think about this and condemn the head end unit unfairly because they are running it without proper 12 volt power. Would you use 22 or 20 AWG wire to run power to an add-on amplifier? No. Ditto for the ground wire. There is an amplifier inside the head end unit. People just don't think of it that way. People just love to trash factory head end units.

 

Now, if I could put a pair of these in the back, that would be awesome. Most people don't even know what these are. These two are on my workbench right now. The silver one in the back I am engineering from scratch. The one in the front will end up all black and is getting totally reengineered as it is my second one and an improvement on the first. No they are not designed for car audio, although it HAS been done in the past. They "only" throw off a hundred watts of pure heat each for 7-10 watts per channel at 1% distortion (GASP! ), which is all that is needed for normal listening volume with efficient speakers, and non-solid state distortion.

 

@Rob41 if that unit works and sounds good, you may have answered my question. That unit does not show any frequency response correction built in, and therefore if people use it and like it and don't complain about altered frequency response with it, then by definition the head end unit must not have any frequency response contouring and the online statements are false, just as they were false with my FJ Cruiser.

Again, there is little doubt in my mind that the JBL head end unit does have frequency response countouring as they often do that for specific vehicle interiors, but with the normal head end unit I am talking about, I doubt it.

Note to self: Go back and listen to the JBL system and see if it actually sounds OK. I doubt it, but I have not heard it.

 

So I can’t speak for the 2023/2024, but I can for the 2020.

Left and right are not in phase.
LF roll off begins at Volume setting 25+.
Left and Right do not output at the same voltage (each of the four channels is different as well).

I have screens of the electrical frequency response for both front and rear. They are nowhere near flat.

The LC2i cannot fix these things but they can be alleviated with something that gives you delay and independent L/R output signal attenuation.

 

This was answered in another thread:

https://www.4runners.com/threads/audio-upgrade.33631/page-4#post-559330

 

I can give you the correction settings later, I’m going through my signal path again later today after swapping out the FiX for LC2i Pro. It’s been a little bit of a bitch getting level matching between all the processors after swapping out the amplifier, max input 4V caught me a little off guard..

 

I'll be interested in what you find compared to the two conflicting sets of data shown in the other thread. Specs tend to change unexpectedly, even within a model year, so if you have a 2020 it may be different from the 2024. What components are you using in your system other than LCi2Pro?

 

I took these directly from the speaker connections before the input of the LC2i, so nothing is in the signal path after the radio. I used 50Hz in referencing the changes in the response relative to the rest of the spectrum and compared that to 630Hz, which is where the spike is, and the overall average between 160Hz and 6.3KHz. I stopped at Volume 45 because you definitely see what's happening by then, and it's not long before the factory radio begins to distort. Stuff is bouncing around a little on the RTA too, so there is a little variation, but you see the trend.

I didn't do the Rear output because mine are capped, but also it's just worse than this to begin with. Maybe someday I'll feel like it. Also I didn't get around to checking phase before it was time to quit and do family shit. I'll put it up when I get around to that too.