Scosche SLC4 Line Output Converter/OEM Premium Amplifier Adapter - 4CH LOC High/Low RCA Converter Car Audio - Add New Amp or Retain Factory Amp - Line Level Converter for Car Stereo - Quality Sound

I was installing an aftermarket stereo in my 1998 Mercedes SL500 with a factory amp. After connecting the speaker wires from the radio to the car's wiring harness, the lowest volume setting was entirely too loud. So I hooked the speakers up to the lineout RCA connectors instead, and the volume was way low (the lineouts were only 2 amps). I looked online for help, then went to two radio installation shops and no one knew what to do. After a little more online research I discovered this Lineout converter was specifically for this issue. It was super easy to install, and solved the problem! The gain adjustments allowed me to get the perfect volume calibration, and the sound is great. My only quibble with this is it's a little large to fit behind some dashes, but it could still be mounted out of view under the dash with longer speaker wires.

This works like it says. Solved my problem with my factory amplifier. I couldn’t listen to the radio stations because they were too loud! Volume 1 sounded like it was on 25! This interface is a cheap fix and solved my sound problems. I highly recommend this to anyone at a great price!!

I used this to integrate into my factory BOSE amplifier/speakers with an aftermarket Android head unit on my 2007 Nissan Armada LE.I read the instructions (as well as reviews) and was very careful when torquing down the speaker wires. I would have preferred to put wire ferrules on the speaker wires and then connect them to the LOC but I did not have faith the screws would be strong enough to crush them properly.Ideally, I would have preferred to have a wiring harness (like on other LOC units) so I could solder the wires from my head unit and have a more secure connection.The gain controls seemed flimsy - I followed the instructions not to push down as you turn them but had to apply an uncomfortable amount of force to break them loose initially.In my case, I had to max them all out (I suspect due to the weak signal from the Android head unit) and the arrow on one was not aligned to the others.That said, everything is working and sound is now good but I worry about how long it will last as the entire unit feels fragile. I also recall using one of these units in the past and having it fail so I do not have a lot of faith in it.As another reviewer noted, the colors on the pre-outs were not correct (switched red/white for front back) but I used the labels as a guide.All in all, assuming it keeps on working, it's hard to beat for the money. Just don't expect LCI quality.

I used this to convert the high level outputs of an Android radio to the low level inputs needed for my car premium sound system.The radio caused a constant white noise because the output was too high. The noise was awful, you couldn’t turn the volume up past 3 or 4 (out of 30) I installed this inline, adjusted the gains and now the sound is great.

I read every review possible for this device before purchasing it on Amazon. From what I could gather, it appeared to be a low-price option for my system that had a potentially good upside. I read some reviews stating that the connectors for the wires are bad (verified to be true - even with soldered wires, but it certainly shouldn't fall out!), and I read some reviews stating the the sound quality was reduced somewhere in the conversion process. The latter claim I can also verify to be true, which is why I am returning this product. More on this shortly.Here's what I was doing: I have a new car with a bad stereo (OEM - of course it's bad). I love music, and drive often - so I wanted a nice stereo. The first thing I did was replace the stock speakers to Polk MM651's and Polk DXi650's. This improved my sound, but not much (since they were likely getting like 5 - 8 watts RMS from my factory head unit). I installed an amplifier to help them really reach their potential - and wow did it ever - but I had the infamous alternator whine. After lots of troubleshooting, I realized it was the high level inputs that were causing it. So I purchased this unit to convert to a low level signal, hoping that would eliminate my alternator whine (although typically the whine is caused by ground loops, I was able to verify that mine was not). This device successfully eliminated my alternator whine, and my system was noise-free! So, in a sense, the device does what it says. However, I quickly noticed that the sound quality left something to be desired. It's hard to explain, but suffice it to say that there was something missing. Also, some of the notes sounded muddy to me at certain frequencies (I suspect the low end in particular, but I didn't leave it in long enough to analyze this further). I am returning this item because of this issue. After spending decent money (and lots of time) putting in speakers and an amp, I was not going to let the LOC be the weak link in my chain.So, I went and did what I should have immediately - I bought an AudioControl LC6i. This product is a POWERED line output converter, sums the incoming signal (useful if your stereo has active crossovers), has a built-in ground loop isolator (eliminates engine whine from ground loops), turns 4 channels into 6 (so you can run a subwoofer from it easily), is easy to install, has high build quality, and also sends as pure a signal as you can get from it with low noise (.01% THD I believe). Not to mention this thing amplified my signal so much that my amp is hardly even turned up anymore! LOVE this device. However, it is 5 - 7 times the price. Worth every penny in my opinion. Oh, and this is a nifty feature too: you can have this device remotely turn on the amp for you. So if you're like me and couldn't get your car stereo's remote trigger to work with the amp, you can simply relay this to the amp. Then the stereo will activate the LOC (via the speaker inputs), and the LOC activates the amp. This eliminated the "pop" noise when I turned on and off my stereo or plugged in my phone/iPod.Install Notes: Not as bad as some say, although the little screws can be a pain. Don't use the awful plastic tool they give you - use a real screwdriver. Adjusting the gains was easy. I had mine turned all the way up (since the device is passive, I can only imagine that turning the gains to anything but MAX is only lowering the signal from your head unit - it can't possible amplify it with no power). The device does feel flimsy, but it is solid enough to stay put in your car without worry of it breaking.Final Verdict:If you are an average person who just wants to eliminate alternator whine and you're sure it isn't a ground loop, or if you just need to convert to low-level signal for your amp and want to keep your factory radio, this may be perfectly fine for you.If you are someone building a nice audio system and value high fidelity sound, don't mess around with this thing. Go purchase an active (powered) line output converter and do your system some justice.