Amp activation issues?

So, in the last, say, month, I've occasionally noticed that when I start my truck up, I'll hear two *thump thump* sounds, as if some dude is in the bed of my truck, whacking on the roof of my Tundra. LOL

I've narrowed it down to the amp, mainly because when it has happened, I've lost all audio (not counting the front dash speakers) until I turn off/on the truck. It happens *SO* sporadically that it's not funny.

I don't 'think' it's the OEM HU simply because this particular issue has only shown up in the last month or two, so I'm thinking it's either a) the LOC (again lol) or b) the amp itself. Anyone else run into issues like this?

 

Sounds like you need to find a different source for you remote turn on wire for your amp.

Theres a delay thats needed during the shut down phase of an amplifier that specifically designed to eliminate speaker pops/thuds when turning off your vehicle.

 

That's kind of what I thought. With that said....any clue why it's only started in the last month or so? The only thing I had done was to replace the LOC as it was faulty.

 

Pics and specs of equipment can help

 

LOL! My apologies, you're completely right.

HU - OEM non-JBL
LOC - 2 channel
Amp - JBL Stadium 5

It's obviously something to do with either the amp, HU or the LOC (possible), simply because the very few times something has happened, the only speakers that play are the dash speakers - which makes sense because everything else runs through the amp.

 

No pics?

 

I mean, I *can*, but it'd literally be just a pic of the amp itself, as the LOC is underneath the carpeting...and it's your standard install (e.g., 2-channel LOC output to the left/right front and rear inputs, then output to the front/rear channels and the sub).

That plus I've been busy as hell so I plain forgot. LOL

 

Update:

So, out of nowhere, *just* my sub cut out. E.g., there's full sound to all other speakers/tweeters....but the sub is essentially acting like it's not plugged in. Checked all the connections, unplugged/plugged everything else back in, etc.

My guess is that whatever was causing the 'thump thump' and such is the cause of this as well. Luckily for me, nearby sound shop (one I actually trust) has an opening tomorrow at 3.

 

SO....had the audio guy troubleshoot, and unfortunately he came to the same conclusion I did - that the JBL Stadium 5 amp is bad. They spent a good hour or two testing everything, and everything else checks out.

With that said, I've got a couple choices:

Infinity 7005A for $329
JL Audio 900/5 for $599
Alpine PDR-V75 for $399

The nerd in me wants to splurge for the JL Audio 900/5 simply because they're fantastic quality; but by the same token, both the Alpine and Infinity amps are great quality, I'm sure, and cheaper; Alpine's never done me wrong. Thoughts? I've got Hertz speakers front/rear, with a Kicker 10" shallow-mount sub. Can provide more info if necesary. For the record, I was fine w/the sound quality of the JBL Stadium 5.

 

Umm, thats a crazy good deal on the jl! For that price its a no brainer to get it.

 

I actually didn't realize that. Well then, I guess my choice is made. (Plus, for this price, I'll be bringing it along with me if I ever sell it.)

 

So i've gotta ask, how are you getting that price?
If you've ever thought that you may want to go all out on the stereo, get 2 of them at that price!

 

I mean, my amp was confirmed to be bad....and they said "We have these amps." I may be wrong - it MIGHT be $649 vs. $599, but yeah, that's the price they have it at. *shrug* They have 2 or 3 in stock, I think.

With that said, this is in the middle of nowhere in Missouri; most people who get systems are likely NOT spending big bux on JL Audio around here. LOL

 

Gotcha. Well, thats a helluva deal! Even at $650 for a brand new one, that's a no brainer. You'll really like it! Lots of power for a small footprint.

I'm not sure if jl has restocked but they were running extremely low on inventory throughout covid. The used one i bought i had to send into JL for repair, took them almost 3 months, but i ended up with a brand new one.

 

Good deal. Yeah, I know of literally no one who has any issues with JL Audio (meaning the quality of it), though I CAN say that if I ever have issues with it, I'll send it in to be fixed. I just called them and they've set it aside for me to be installed next Monday.

 

Thats great! Let me know how you like it!

 

I'm sure I'll love it; but yeah I'll be sure to let you know.

On a side note, as a guy with an aftermarket everything *except* the HU, is it worth trying to 'tune' it? I was trained as an electronics tech in the Navy, so I understand the science and the point behind it, but as busy as I am/have been, I've never gotten seriously into the weeds on this. My essential requirements for a sound system are

- add some bass
- add some treble
- sound less crap than the stock system does

LOL - so upgrading the amp/speakers, and adding a sub, does/did all that, but with a stock HU, not sure if there's much tuning to be done, and/or if it makes much of a difference.

 

Holding strong on keep that head unit huh? ha. I was right there with ya.

About your requirements....by bass do you mean the lows or the midbass? Lows are easy and it sounds like you've already got that covered with a sub(s). Midbass is a little more tricky/expensive. Are you running anything in-between the head unit and the amp?

 

For now, yeah. LOL It's not that I just love the HU *that* much, but right now, at least, it's under warranty by the dealer. Plus I've had no issues with it.

Right now, only thing between the HU and the amp is wiring and the LOC, as I've largely been satisfied. I'd agree I could add a bit more mid-bass, but it's not killing me. Honestly, I wasn't as impressed as I thought I'd be with the Hertz speakers *UNTIL* the amp went out; now it's just the speakers, and frankly, I'm impressed enough with them/their output that I'm likely fine where I'm at.

 

I hear ya, if you aren't pissed at the head unit, then no reason to change anything. I went down the rabbit hole and it was the last thing that went...it probably should have been the first thing to go if i would have known how crazy my stereo would end up.

There really isn't much tuning that can be done. The passive crossovers is going to take care of any "tuning" that you would do. Just set the HPF and LPF on the amp and call it a day.....your shop will probably take care of that for you.

 

Yeah, I mean, I used to be seriously into tweaking stuff, but it wasn't usually sound systems (simply because I was broke at the time ROFL). Now? I've had issues that I now know to have been the LOC and the amp all along - probably masking each other. Not constant issues, but they've super intermittently popped up from time to time over the last 18 months.

My point? Given the above, to simply have a 100% reliable system is enough for me. In the future I may upgrade the HU but for now I'm good.

 

what loc are you using?

 

Nothing special, I think; if I remember correctly, it's a 2-channel Scosche.

To be clear, when I said "I've had issues that I now know to have been the LOC and the amp all along," I was referencing a few months ago. I had the LOC replaced about 2-3 months ago. It took so long because the issue only showed up on something like 1 out of every 50 starts. Drove me freaking insane. I'd lose ONLY the right front channel.

Once it started happening more frequently, I switched the FR/FL outputs, and the issue traveled, so I knew it wasn't the speaker, wiring, etc. Swapped the LOC output to the amp and it STILL traveled, so I knew it was the LOC. Had that replaced and all was well until the amp went kablooie. LOL

 

You might want to talk with your shop about upgrading the loc. Some of the better ones will tackle the bass roll off....or the JL Fix86 will re-tune the factory sound curve.
You could also just ditch the loc and use your speaker level inputs. On the HD900/5 they sell an "adapter", but its just rca's with one end clipped off (i'm sure your shop could fab it up for free).

 

Got any recommendations? When I had them replace the LOC, they had some from Audiocontrol, but if you've ever dealt with sound shops, you know most of them essentially think "It's a LOC....you don't need this spiffy one to do what this cheaper one can do."

 

Ive only used the fix86, it eliminates the sound curve the head unit applies, but comes at a price.....you have to leave the head unit at 75% and use a remote knob to control the master volume and sw level.

One thing to consider is that whatever money you spend on a loc, could be used to replace the head unit. It really is the weakest link left.

 

Got the new amp installed and it sounds....meh!

J/K - sort of. The amp sounds fan-freakin-tastic. I can easily tell a difference in the mids/highs. The issue (and this is totally on me) is twofold - only one related to sound:

1. Evidently damn near everyone that goes to this shop says "I want all the bass, please." Issue with this is that without the remote knob (which I'm definitely getting), the only way to remove most - not all - of the bass is to crank the bass almost all the way down on the HU...except then there's almost squat for lows/mids coming out of the door speakers. This I can fix myself.

2. More importantly, evidently the dude didn't know there was an underseat vent there. *facepalm*

So I'm going back Wednesday so they can neaten up the wiring, relocate the amp a bit forward of where it is, etc. I'll tweak it myself.

On a side note - what're you using (or ARE you using anything) for an 'amp rack'? I can tell I'll need one. The one I have from Tech12Volts won't work because due to wiring constraints, they had to mount this one side-to-side instead of front to back. (Which, actually, I prefer - it means all wiring is accessible by the front seat.) If nothing else I can probably jimmy something up from a cutting board or what have you, but I'm really hoping someone says "Oh yes, there's a metal amp rack that will fit a JL Audio HD900/5!" LOL

As an illustration, I went and looked @ your build thread and found this pic:



Pretend the HD900/5 is where your amp is above, running side-to-side, between and in front of the back legs of the front seat. Issue with that, of course, is that's where the underseat vent comes out, so I'll have to have some sort of rack to elevate it such that it clears the vent. They're at least going to move it forward a bit for now, but that leaves the amp 'loose' under the seat, which I have a HUGE issue with. For a week or two I'm OK with it, but any longer than that, and either I'll build a fix, buy an amp rack, or have them do it.