Hi Guys,

So I've got a 380 and loving the standard system, however it feels lacking a little in the bass department. Sounds really good for interior only speakers, but can't substitute a sub imo.

What I would like to do is use my Soundstream 4 channel amp as it has low level inputs which accept inputs straight off the headunit.

My only issue is, how should I wire it up? Can I run the amp inputs in paralel with the rear speakers, or will this cause impediance issues with the headunit? The other option is to run the sub off the front 2 channels, and then use the spare 2 channels on the amp to power the rear speakers, but then i'll have rear speakers which are much more powerful than my fronts, and I have no idea how well this will scale with headunit volume. Something to play with the gains I guess.

Or should I go to the effort of powering my fronts, would the stock speakers handle 130wrms? I doubt it lol.

I don't want to start replacing speakers and I'd prefer not to touch the rear's other than to piggyback their input, as I genuinely think the standard speaker setup is fine for mid/treble.

Thoughts?

Cheers,
Leigh

Well ,what l did was to run the signal from the rear speakers into a pair of aerpro high/low converters and fed these signals into a 4 channel Alpine amp and then used the amp to power a set of Kenwood 6x9 rear speakers and a Sony 12 inch sub.

Not the gee wizz brands ,but meh,it works,sub punches really nicely and sounds great ,all for a cheap set up.

Well ,what l did was to run the signal from the rear speakers into a pair of aerpro high/low converters and fed these signals into a 4 channel Alpine amp and then used the amp to power a set of Kenwood 6x9 rear speakers and a Sony 12 inch sub.

Not the gee wizz brands ,but meh,it works,sub punches really nicely and sounds great ,all for a cheap set up.

Yeah I'm talking soundstream amp with MTX thunder sub/s, nothing huge but I wouldn't say bargain basement. My main issue is whether or not I can power an amp and speakers off the same line out, like will the headunit see the amp as another resistance and potentially cause issues.

RCA are low level, speaker input is high level :)

Unfortunately I don't have too much knowledge when it comes to sharing speaker wiring into high level inputs, should be plenty out there if you do some google research. Be sure to fill me in with how you end up going about it!

Your idea of splicing into the rear speakers can work since they will only be signal cables anyway. The trouble with high level (speaker wire) inputs is there is more chance of them picking up noise along the way to the amp.

The obvious issues could be the impedance issue and the lack of tune-ability since you are splitting a signal.

I`d would just stick to the sub for starters, and yeah, chase up some hi-level to low-level converters, as Maggie suggested, there are many makes, with many prices, I haven't used any, cheap or expensive........And no parallels please.

And I would not be cranking anything more than a after market head unit power equivalent to those 15 watt speakers fitted the 380. With that said, its possible to measure (dose out) the output of an amp to the 18-20 watts you could throw at them.
IIRC, you play a white noise track and measure with a multi meter, and dial in 20 watts measuring the volts. Its a bit of stuffing around, is it worth it, nuck fose. But the other two channels are there, would I do it in my car, no, I have pIoneer h/u in my 380, with a stock h/u though, I would look into it with serious consideration

BTW the rear speaker wire is under the parcel shelf carpet, its very short, culminating in a loom plug to the speaker, if you want to tap in to wire the best bet is popping the speaker covers off, done from underneath, by pressing a 6mm socket onto the white plugs, they will just pop up with a bit of force.
To take the parcel shelf carpet off, never did before myself, but I'd presume the rear seat comes out to get to it.
The bench of the the rear seat is not like a magna, it has to pulled up sharply.

pea and ham, a speaker wire has virtually no chance of picking up interference because of the high voltage running through them, especially compared to an RCA cable, with such low power is easily interfered with, RCA require shielding because of this, you don't see much speaker cable with shielding now do you.
In fact the only non shielded cables that you have in your home or car, are the high voltage ones, actual power and speaker cable.

The main issue with noise induced into your bass system, will be with cheap converters and long low power rca's.
Just running a sub channel, this setup will be very forgiving, the noises induced are usually of a higher frequency, well above the sub-bass area.

Yeah I'm talking soundstream amp with MTX thunder sub/s, nothing huge but I wouldn't say bargain basement. My main issue is whether or not I can power an amp and speakers off the same line out, like will the headunit see the amp as another resistance and potentially cause issues.

Like ive said,i power both rear speakers and an amp of the rear speaker signal,taken from the rear speakers and have had no problems with the head unit or the sound it produces.

Only thing is the fader has to be set the same for the front or rear ,as when you fade to the front ,you loose sound and bass at the rear ,so i just leave it set at the stock levels.

Like ive said,i power both rear speakers and an amp of the rear speaker signal,taken from the rear speakers and have had no problems with the head unit or the sound it produces.

Only thing is the fader has to be set the same for the front or rear ,as when you fade to the front ,you loose sound and bass at the rear ,so i just leave it set at the stock levels.

Hang on so you power the rear speakers off the headunit, as well as the amp? In your original post you said you powered the amp via the rear speaker inputs, and then amped the rear speakers, I'm confused lol.

Sorry I think I did mean high level, and my amp does have high level inputs so I don't need any converters do i? As you said I should just be able to run the amp using a low pass freq so shouldn't have any issues in that department. It was whether the speakers and amp could be powered off the 1 single wire I was worried about, however I'll give it a go this weekend and see how it sounds. I have the fronts faded to about 2-3 anyway as I prefer the rear speakers to be background noise. Also I do have 2 subs but i'm worried dual 12" will be too much bass for stock speakers to handle, but I'd like to keep the other 2 channels free for later use just in case I do upgrade a set of speakers in the 380 or add the 2nd sub in.


Your idea of splicing into the rear speakers can work since they will only be signal cables anyway. The trouble with high level (speaker wire) inputs is there is more chance of them picking up noise along the way to the amp.

The obvious issues could be the impedance issue and the lack of tune-ability since you are splitting a signal.
impediance is my biggest worry, I don't want to burnout the headunit circuits or have it cause the rear speakers to distort etc. Tuneability i'm not too fussed with as I can control LPF/gains and I think I even have a remote bass control for this soundstream amp, the biggest tuning problem will be getting the bass to go up nicely with the in car volume, once that is tuned i'll be happy.

Cheers for the help guys!

pea and ham, a speaker wire has virtually no chance of picking up interference because of the high voltage running through them, especially compared to an RCA cable, with such low power is easily interfered with, RCA require shielding because of this, you don't see much speaker cable with shielding now do you.
In fact the only non shielded cables that you have in your home or car, are the high voltage ones, actual power and speaker cable.


My mistake I wrote that around the wrong way, so your right.

Impedance won't be an issue, the high level inputs do not contribute a resistance to the speaker channel. If your really paranoid just check it on a multimeter before you start cranking it.

One more thing I just thought of, what do you guys use for a remote amp turn on?

Use the accessory wire on your head unit

My mistake I wrote that around the wrong way, so your right.
Its all good pea's, good to have you around to keep me honest too, thanks. Marty

One more thing I just thought of, what do you guys use for a remote amp turn on?


Use the accessory wire on your head unit

tap into the cig lighter/phone charger at the front of the consol

Hey Woob, would there be any harm in doing this, I would only put a 5 volt trigger up to my amps. Unless there is a powered converter that could create one, unless, as you suggest, the 380 OEM stacker has one, NFI.

Hey Woob, would there be any harm in doing this, I would only put a 5 volt trigger up to my amps. Unless there is a powered converter that could create one, unless, as you suggest, the 380 OEM stacker has one, NFI.

The standard 380 stacker may have one for the antenna, but this may switch off if not listening to the radio. I'll have to grab a multimeter and work out the best wire to tap into. So you recon amp triggers should only be 5v?

Amps will take a 12v remote signal all day long. When I was testing amps in an old install of mine I had a switch on the dash to quickly disable amps when needed