Pre-amp vs. speaker level inputs for external Amps...?

[THS_Cruiser03]

Sound quality question:

I'm planning to upgrade the stereo in my '03 base. I need some amp hook up advice from those of you who have done this.

I currently have two sets of matched components (5.25" & 6.5") and an 800 watt 4 channel amp. I'm trying to keep the stock look, so I'm using the factory stereo.

My dilemma is this: Factory radio doesn't have pre-amp outputs for the amplifier, only the speaker wires for the four channels. I've seen line output converters on the market such as this one:
Scosche SLC4 Four-channel line output converter at Crutchfield.com

Which will allow me to hook up my factory radio to the amp via the pre-amp inputs (which I understand give the best sound quality)

But I'm wondering if I will have equal or better sound quality just running four sets of speaker wires from the amp to the speaker locations? What is the skinny on the line ouput converters? Do they chop the frequencies at all? What about noise? Any known problems with amps and PT factory stereos?

It would be nice to only have to run 6 wires for the speakers instead of 8?

Also has anyone run wires under the center console of automatic PT's? Is there plenty of hiding space in there for the amp wiring? (Amp is going under the drivers seat)

Thanks!

Tom

[Michaelexists]

I really think the sound quality is going to suffer leaving the stock deck in the car. But if you're really into keeping a stock look and you're concerned with sound quality, you'd be best off wiring the amp to the speakers. The line converter is clipping incoming signals, which is going to certainly distort your sound. I don't know how much. As far as room under the center console is concerned for wiring, you've got pretty good head room down there.

[THS_Cruiser03]

Thanks, I'm not sure how much the sound quality would suffer either, but if in fact the line ouput converters clip the signlas - then I'm not cool with that, (unless of course the signal clipping is above say 16khz which I'm not likely to hear anyway). I did read about a guy who bought the LOC to hook up an amp to his Dodge Ram stock stereo and he talked about distortion problems -

"The Scosche SLC4 line level converter was exactly what I needed to connect my stock '06 Ram HU to my new Profile AP1040 amp. The adjustable gain controls allow for full control of the output signal. If you have trouble with distortion between your stock HU and your after-market amp, regardless of year/make/model, GET THIS!"

So this got me worried that I might have distortion problems, but then again he may be overdriving his stock speakers causing the distortion. Thoughts?

You're probably right, an aftermarket deck may have better sound quality - but I really want to keep the stock look and I've had two systems stolen out of previous cars, and I'm not willing to go there again.

I do think the stock 6 speaker stereo is pretty decent. When I play my CD's or MP3 player the sound quality is good - It just doesn't have much power to play loudly and the system needs more bass. Which is why I'm adding 100w 10" passive sub along with the 800 watt 4 channel to run the component speakers. Overall it should be a nice improvement, it's not intended for competitions or car shows of any kind. Just my enjoyment.

I suppose I can hook it up via the speaker inputs and see how it goes....if I have problems then maybe I'll need the LOC.

We'll see.

[AlexJB]

you thought about an aftermarket unit in the glove box?

You seem to know enough about amplification and frequency to understand that the more times you amplify then chop down the signal, the poorer the quality will get.

I used to run a minidisc head unit with 2 pre-outs and a 4 channel amp with channels 3&4 bridged into one and ran the sub from that and MB quart reference series from channels 1 and 2, this was loud and had a great response range. simple and uncluttered is good.

If you must keep the stock look, is there enother Chrysler unit that has pre-outs that could fit?
If you want to still use the 4 channel, you could get a mono or 2 to 1 bridgeable amp for your sub.

Basically the amplifier in any head unit OEM or aftermarket is crap in comparison to a dedicated amp.
The signal out from OEM is already cut and a little distorted, put this into a chop down unit to then amp it back up in your seperate amplifier and it will be like that tape recording of a tape recording of a tape recording you once had of new kids on the block...