JBL Premium sound system problem

I got the USB mini B 4 pin cable from amazon and it fits into the receptacle on the JBL amp. Here is a pic.



I took a PC out to the car and tried getting it to recognize the amp but kept getting a message form the app saying 'No available comm port'.



Tried troubleshooting a little bit on windows but couldn't get it to work. Thinking it may have something to do with the BIOS settings on my laptop but I didn't know how to access them on this particular pc.

 

First off, did you run the "usb drive" installation program before installing and launching the amp tuning program?

I assume you've already tried changing the order of things around? Stuff like when you're powering up the different devices, when you're connecting the cable, when you're starting the software, that sort of thing?

The instructions say:
1. Connect the computer and amp using the USB cord.
2. Power up the audio system(in this case, turn on the car)
3. Start the software

If you haven't tried changing things around, try having the cord already plugged in before you boot the laptop. If that doesn't work, try plugging it in after bootup. Try starting the car before starting the software, and also try the reverse. With just the laptop running and the car off(but the cord plugged into the amp), try plugging and unplugging the USB cord into the laptop and see if you get the "new device detected" sound. (low pitch beep followed by a higher pitched beep) If that does nothing, try starting the car to power up the amp and try again with the cord to see if anything changes.



And this is a long shot, but try putting the laptop into airplane mode before launching the software. A user on reddit was having a different issue with the program not being responsive, and tech support told them to try it. It worked for that user and another user who responded.

 

In regards to the speaker replacement, what have you replaced them with, have you heard a noticeable difference, and were you able to do the replacements without any other modifications(iow, were you able to keep the dash and A-pillars completely stock)?

I might be interested in doing gentle upgrades, but I'd hate to spend significant money only to get a 1% improvement. (I'm not going to sound deaden or add a sub enclosure or anything.)

I'm grateful that you're the trailblazer on this.

 

A little bit. When I got out to the car I was dealing with a pretty dead 12V battery since I hadn't attached the maintainer. The cable arrived late in the evening but when it came I went out to the car. Had to wait about 20 mins for the battery to get enough charge to start the car. Once the care was started I didn't turn it off.

I did try unplugging the usb cord from the tablet before and after opening the app. Tried installing the drivers even after I think they where already installed. Restarted the computer a couple of times. The JBL DSP Amplifier manual mentions this error but do not give a lot of information on how to troubleshoot it in windows. Here is an excerpt from the manual of the steps I was following that also mention the "No Comm Port Available" error message.


I started googling information about "Comm Ports" in windows and made a little headway but still couldn't get it to work. By following some instructions on Windows forums I was able to add "Comm Port" to the device manager but it still shows an exclamation point next to the icon in device manager. The drives did not show up in the Windows Device manager for the amp ever.

I was using a tablet I don't use very much and still has Windows 8 installed.

 

For me the stock sound lacked clarity on the high end. I found it really hard to hear vocals on some tracks and the sound was overall just fatiguing to my ears. I just threw in some stuff I had laying around to try. A few tweeters I have used before that I know have a natural flat response since I can't really do much if any tuning. I already had the adapters for the dash and pigtails for the wiring harness leftover from previous projects. In the dash I put some Vifa XT25SC. I love the way these sound, unfortunately the JBL seems to cross these somewhat high around 6k hz. This position uses the standard Toyota oval shaped dash bracket that they use on everything. In the JBL pillar tweeter I placed some Peerless OC24SC, these required a little more finagling but it was not difficult to get them fitted. The JBL attenuates these greatly and they seem to have a high pass crossover around 12k hz. As you've seen before I put a JBL basspro in the trunk.

The result was an overall improvement for me , the sound is not only smoother but far more clear and crisp without being as fatiguing. The tiny little JBL sub adds much needed boost to the bottom end but it's not a window rattler by any means.

Ultimately I would like to dump the dash position and redesign the tweeter pods on the pillars so I can just run the Vifas on-axis. I have some nice 6.5" mids I could use for the doors but I'd really like to do a 7" or even in 8" if possible. I'm going to pull those panels here soon to see what I can fit. I will just 3D print baffles for those as needed.

If if you want to keep it basic I would look at replacing the front dash and front doors and call it there. A common upgrade speaker for the dash are the kicker tweeters from a Subaru PN: H631SFJ101 which should plug and play. The Kicker KSC270 would probably work nicely there as well. In the door I would do a 2-way 6.5" , you have a ton of options for those.

 

Thanks for all the info. I guess I should have said what I usually listen to, but it probably wouldn't have changed anything. It mostly breaks down into two categories: youtube videos/podcasts and classical/jazz. For the former, I'm mostly interested in speaking voices being clear over the noise of the engine/road/wind. For the latter, I'm looking for an extremely flat response; along the lines of what you'd want in a studio monitor. When I'm listening to wind ensemble, jazz ensemble, orchestral, or acapella music, I want it to sound as true to the original performance as possible.

On the other hand, I don't have a long daily commute, so it's not a high priority to upgrade as much as I wish it was. Outside of regular two minute trips around town, I maybe spend an hour a week in the car on trips greater than 10min. It's not worth it to me to spend large amounts of effort and money on something that benefits me so little on a daily/weekly basis(though part of me really wants to).

 

On that one specifically? No. On a kind of similar low profile 10" under seat powered sub, yes.

Even with the LPF set to 80hz it could be localized when you turned your head. Because it was an under-the-seat sub it meant that the driver and passenger had a different experience with the audio from it. And it was noticeable. Though yours can go in the trunk to be more centered to fix that.

Despite its limitations it did fill out the low end a bit. And if my choice was no sub or a slim self powered sub, I'd at least have a slim self powered sub. Also the self-powered one I had in my last car was half the price of the kicker so maybe the 2x cost kicker sounds much better than what I had.

That was all in my old car. In my current I run a dual 10" downfiring sub that sits in the trunk. It is far better of course.

If you don't plan on having the 46HS10 under a seat, you can probably find a cheaper sub to sit upright in the trunk against the backside of the backseats.

 

I also wouldn't put a sub under the seat for sound quality reasons. The spare tire well is a great option assuming you're not going to put a spare back there. The foam pieces are an extremely inefficient use of the space. You would be better off building something out of MDF. You could do a cubby with integrated sub? The Prius has some very nice spaces in the hatch area to stuff a sub into. I will be putting mine in the one on the driver side cubbie since I don't want a sub interrupting the storage space, and I want a spare. I've been trying to hold off for someone to make something that fits in there. I can do fiberglass but I'd rather pay someone else to do it.

 

Doubt the owner is here but I've chatted with the installer, super nice guy and extremely knowledgeable.

That car had a base stereo non-JBL.

 

Haha nice , I emailed him back when he first posted about the build I think on tiktok? I found it while I was scouring the web for information. He sent me a very long and detailed response to my questions where most would just tell you to go pound sand. Yea 6k for that build is a big yikes but I'm sure it sounds good.

 

ps. I ordered one of those cables. I will give a shot with my laptop.

 

Cable didn't work for me either. No error , just nothing from the amp. Not even detectable as a device.

 

Fwiw, someone analyzed the signal going to rear speakers from a JBL in a Corolla. Here is what the rear speakers get. Yep just barely a tickle of mid-range.



If you have a JBL you really only have two options:

1. Install a DSP and your own AMP. You will probably lose some functionality of the head unit. (carplay voice prompts, possibly also w/ android auto) Imo this will be fixed eventually.

2. Keep it basic. Do a beatsonic amp, maybe upgrade some of the drivers. Splice @ line level in to add a powered sub.

 

Screenshot From 2024-04-19 14-29-58 by soft_r posted May 14, 2024 at 6:58 PM

Since you posted that, I'm just including this. 192kbps -3db pink noise from head unit > LOC > RCA/3.5mm cable > attenuated 3.5mm adapter > tablet running friture

Gives an idea of what the base front speaker signal is doing.

This is for non-JBL but I doubt the JBL has been tuned any different but at least you have it for comparison.