Scosche OEA4 OEM Premium Amplifier Interface Adapter - 4 CH Adjustable LOC Level Converter - Retains Factory Car Audio Amp - Line Output Converter for Car Stereo Amplifiers - No RCA Connection Needed

I have a 2006 Silverado HD and really wanted to add a backup camera. One thing lead to the next, and I ended up replacing the head unit (was the original Bose system) with a flat screen (Kenwood) that could do wireless Carplay, view the backup camera, and show maps, along with a matched-set of 4 speakers and 2 tweeters. I did not dig down into the center console to replace the sub. Everything was great ... except the HISS! I came across a random blog that talked about this HISS that will occur when integrating a new system into the older Bose systems that Chevy used in the early 2000s. The hiss (sounds like white noise when engine is not running and volume is all the way down) is a result of the new unit's amp running through the old Bose. The blog recommended bypassing the entire Bose amp (about 5 hours of work digging into the center console to get to it) and running all new speaker wires from the new unit to all speakers... or get this Scosche Oea-4 and wire it between the new head and the harness. For $10, it was a no-brainer. I already had wired the Axxess Integrate AXDIS-CL2 AXDIS-CL2 Data Interface between the OEM harness and the new unit so it would integrate with steering wheel controls and OnStar, so I placed this between the head unit and the Data Interface. It takes the 8 speaker wires and allows separate control of output from the new head unit to each speaker. I now have ZERO HISS. I am surprised there is not more info about this issue or the little jewel. Very happy with the result. BTW, I am a professional musician by trade, so I am a little picky when it comes to results - this delivered!

I recently used this line level converter recently when I installed an aftermarket Android Navigation unit in my 2006 Audi A4, replacing the factory RNS-E navigation unit.VW/Audi are notorious for using non standard voltage and impedance in their audio systems, particularly when they are the BOSE systems. This causes volume level imbalances and system noise (hum/buzz).Although there are several audio configurations in VW/Audi, in my case with the BOSE all speakers are powered by external amplifiers fed by a line level signal from the head unit. Audi doesn’t use a traditional line level voltage so I used this “Hi/Lo” converter to tap the speaker output wires, I set the adjustment pots to about 25% and then fed the output through ground loop isolators to remove the Hum/buzz. For reference, I used the Radioshack ground loop isolators, I’ve used them in the past and at $15 each, they perform very well removing 100% of my system noise.This scosche oea4 unit is very cost effective and did mostly what I needed for installing an aftermarket head unit in an Audi with BOSE. One improvement would be if it had the ground loop isolation built into it but at the price point and simplicity of use I’ve very pleased with it.Note that the adjustment pots are very fragile, it even says in the instruction to use great caution not to over twist and break them. I did not have any issue with them although I’ve seen people complain about breaking them; I presume most of them didn’t read the instruction and twisted it to aggressively.Although my sound system is currently working properly with the correct volume levels and no noise, I am still going to try replacing this Scosche Oea4 and RadioShack Ground loop islolators with a PAC SNI-35 which is an all-in-one Level converter and ground loop isolator which already has female RCA connectors on it (I had to solder them on to the Oea4)

I use these religiously on 2003-2006 GM trucks with the bose amp. This is a quality and cheaper alternative to the $150 interface box that you'd have to use otherwise. A $10 wiring adapter and one of these to run the speakers thru and you're good. This will not retain the warning chimes so if you prefer to keep them, this is not for you. Personally, I hate the chimes and glitchiness that comes with aftermarket interface units. I've tried countless brands and they never seem to jive with the vehicle correctly. 5 stars for this inexpensive alternative.

It appears to be working, I haven't actually needed to make any adjustments though. But I really wish the dials were easier to tweak.If they made the dials better I could rate it higher.Used in a 2010 Nissan Frontier with Rockford Fosgate system and a Pioneer headunit.

This product does the job. Barely. I had the mindset of, "if i'm going to have to buy a radio for my '90 Lincoln Mark VII SE with JBL sound", then I will buy a real nice radio with a lot of features. I installed the radio with the Scosche part and it is good enough to get sound through. I should have bought the original radio that belongs to my car... I am searching for the original radio now to replace the after-market radio and Scosche part. Hope this helps

Package arrived super fast and well packed in the box. I've used this brand in other car audio installs, recommended 100%.

For my Pontiac vibe 2005. Installed this between my aftermarket headunit and the stock speakers (moon and tune package). This was the only thing that worked to bring down the volume on the speakers. You just splice the speaker wires right in, nothing else I've tried worked. It is difficult to get all the speakers the same volume level though with the flimsy knobs included for 4 way gain control.

Installed an aftermarket JVC radio in a 2003 Chevy 2500 with BOSE factory sound/amp. There was a constant static noise on all setting even with an interface module. Installed Scosche gain controller and it took care of the background noise. Aftermarket head units provide an amplified signal that causes background noise with the BOSE. After installing no longer that static/white noise at lower volumes.