Profile: Navone Engineering specializes in providing adapters and filters. We also offer vintage electronics, line drivers, pulse triggers and iPod adapters. We provide NE-684V, which is a four-channel adapter designed to interface aftermarket decks to factory amps. It is fully transformer isolated with phase and frequency compensation to prevent noise & damage to aftermarket or OEM components. The signal level can be adjusted from a maximum of 9.5 Volts rms down to zero volts. It features four floating speaker level inputs and outputs.