Sub & speakers not working

[Muttley]

Hi,

I recently acquired a new car but the sub and front speakers are not working. It has a Pioneer headunit which I swapped with Pioneer from my other car with same results. The rear 6x9s are coming straight off the head unit and they work fine. The front splits and Pioneer sub come off a BOSS 4ch amp. The amp is getting power (the fan and lights work when the HU is on) but no sound. The VU meter doesn't move. I have checked the leads from the HU to the amp and one of those seems dodgy (O/C) but doesn't really explain why I get nothing out of it at all. I am suspecting the amp, but don't want to replace it unless I have to. It looks like a pretty flash unit.

Any suggestions on how I can narrow down the root of the problem?

[sganro]

if you have a mate with a amp, or can get ya hands on one try it in your car and see if that works. If it does, your amp is buggered. If it doesnt then either the RCA cable going from yeah head unit to the amp is stuffed, or the head unit itself isnt sending any signal from its rca pre-out. Its more than likely not the head unit though as you said you changed it and got the same result.

[Shaneus]

First if it is a BOSS amp I doubt it is "flash".

Try plugging in a mp3 player with a 3.5.mm to 2 RCA or anything with RCA audio outs..If this works this means there is an issue with the RCA's from the H/U or the H/U it's self is stuffed.

If this doesn't work then there maybe be an issue with the AMP. You say it powers up ect. so get a speaker and plug it into the out puts, this will eliminate there being a fault in the wiring.

That's all i can think of at the moment. Good luck and let us know how you go.

Shaneus

[calais_cruzin]

agree with 2nd post.

I would just replace that RCA with sum new onse, if u cant get a hold of another amp to test the signal.

The amp isnt goin into protect mode is it?

[Muttley]

First if it is a BOSS amp I doubt it is "flash".

He he. I should add this is my first amp so I am easily impressed . By flash I mean, apart from the shiny chrome finish, it has a lot of controls for setting input and output levels. I don't mind too much replacing it if it really is cactus - something a bit more compact and in a better location (this one is in the centre of the boot floor with a false floor built around it. Not very convenient for getting the spare tyre out!).

[Shaneus]

Sorry if that was a little harsh, but it is in your car so if you like it then that is all that matters.

But sganro said, getting another amp and using all the current stuff will let you no if it is the amp or not very quick.

If you can't get a hold of one for free off a mate, you may want to try a cheaper way before spending 200+ on a new amp.

[Muttley]

No offence taken. I don't think I can lay my hands on another amp, but I do have some old speakers (the originals out of the commy) and I hadn't even thought of plugging an MP3 player into the input. That I can do. I did try plugging the leads from the HU into the aux input of a portable stereo and got nothing there either. I need to check if the stereo works. Do the preouts have to be explicitly enabled in the HU or do the put out signal all the time?

[calais_cruzin]

Sum have a feature to turn off the pre outs, mine does, soo it mite be turned off in the menu, worth a look.

But i think it turns the amp off (cuts power to remote wire) when its not activated, but this im not sure on.

[Muttley]

Ok. An update. I put some spare speakers on and plugged an mp3 player in as suggested. Nada. Something else that was bugging me is that when I check the voltage across the power leads with the amp off it measure 12v, but when I turn the head unit on, and hence the amp powers up, it drops to virtually nothing. When I turn it off again, it gradually comes back up to 12v over the course of a few minutes. So then I turned it on again and pulled the power (+) out and the fan kept going. Turns out it is powered off the remote wire. Me thinks amp is stuffed.

So. What to replace it with? Basically it has to drive a Pioneer sub and a set of unknown splits at the front. The sub is in a twin sub box so I guess there is the option of adding a second sub, although it seems unlikely. Do you really need that much bass? Would you run 2 subs plus splits off a single amp?

Suggestions for a moderately priced quality amp?

[StoneX]

Pretty much anything will do a better job than the BOSS amp... If you're on a small budget, Jaycar (Response) amps are decent quality. The 4 x 100 would be a good choice.

If you have a little more money, look at the name brands from specialist car audio stores.

[Shaneus]

I second the Response Amps, I have them and they r great. If you say you are an Electus customer they normally make them cheaper for you. the 4 x 100 may be a little high for your splits so keep the gain downs so you don't blow them. Or get one amp 1 x 800 or 2 by 150 for the sub, and 2 x 80 or 4 x 50 for the splits.

P.S. did you have the head unit on when you plugged in the mp3 player, if you didn't it wouldn't have powered up the amp.

[Muttley]

I had the head unit on but volume turned right down.

I have just got back from Jaycar with a new 4x100 amp. They have them on sale for $269 this week. Thanks for the tip about the gain.

[Muttley]

Some good news and some bad news and some good news.

The good news is it wasn't the amp after all. Turns out the main fuse from the battery was loose in the holder. Crimped the holder in a little to get a nice tight fit and away she goes.

The bad news is that I didn't work that out until I plugged my new amp in and it didn't work either. So now I have forked out $270 that I didn't need to.

The good news is that I have a nice new amp. Still in the process of doing some tidying up and rewiring. I noticed the old BOSS amp seems to drive the sub a lot harder, but the front splits sound like crap. With the new amp the splits sound much better.

There are so many settings between the amp and the head unit that affect the sound. Any guides on how to tune the system?

[wrx884]

thats normal bout the boss amp pumping louder they normally do its there sound quality and their known reliability thats given them a bad name

[sganro]

IMO, its all good news for you. Even though it cost ya $270 that it didnt really need to, you now have a good amp which i reckon is worth every cent you paid for it. There are heaps of threads with people saying good things about response gear (im one of them ), so im sure you wont be disappointed with your new amp. You might find that you get a better life out of your splits now too.

[StoneX]

Amplifier Gain and Crossover Adjustment Tutorial

Have you go the sub bridged from two channels or just running from one?

The Jaycar should "pump" the sub alot harder as it has more power... I'm not aware of any BOSS amps that ever made over 100Wrms x 4.

[Muttley]

Sub is bridged across channel 3/4. It's sounding better now. Certainly lots of movement. Just need to experiment with all the settings.

BTW should the sub box be ported or sealed? I know this gets asked many times but there doesn't seem to be much history on the forum to look through.

Thinking of going and getting some Jaycar splits to replace the Cadence splits there now.

[StoneX]

Ported or sealed depends on what sub you have and what music you listen to. The subs T/S specs determine which type of box suit it better.

Although Jaycar splits are well regarded, I would say they're only a step up from stock, not something you'd change from a name brand to.