Review on 🔊 Enhanced SEO: Scosche OEA4 4-Channel Adjustable Factory Amplifier Interface by Alex Mitra

A4 replaces the factory RNS-E navigation box. VW/Audi are notorious for using non-standard voltages and impedances in their audio systems, especially when it comes to BOSE systems. This causes volume imbalance and system noise (hum/hum). Although VW/Audi has multiple audio configurations, in my case at BOSE all speakers are driven by external amplifiers fed by a line level signal from the main unit. Audi doesn't use traditional mains voltage so I used this "Hi/Lo" converter to connect the speaker output leads, I set the trim pots to around 25% and then routed the output through the ground loop isolators to remove the noise. buzz. For the record, I've used Radioshack ground loop isolators, I've used them in the past, and for $15 each, they work very well and eliminate 100% of my system's noise. This scosche oea4 block is very economical and basically does what I need it to do. to install a non-original head unit in an Audi with BOSE. An improvement would be if ground loop isolation was built in, but for the price and ease of use I'm very happy with it. Please note that the adjustment potentiometers are very fragile, the instructions even say great care is required. so as not to twist or break them. I haven't had any problems with them, although I've seen people complain about them breaking; My guess is that most of them didn't read the instructions and aggressively misrepresented it. Whilst my sound system is currently working correctly with correct volume and no hiss I will still try to replace those ground loop isolators from Scosche Oea4 and RadioShack with a PAC SNI-35 which is a universal level shifter and ground loop isolator there are already RCA jacks (I had to solder to the Oea4)