If you want the best sound and all the dynamic range your system is capable of, you need a signal line driver. In the 90’s, any decent deck had 4 volts of preamp output. Some had 8V and some even had 12V.  But now, even the best units have only 4V RMS and most are barely 2V, and that’s 2 volts only at 1KHz at clipping. Ask the deck to produce preamp voltage at all frequencies (like when you’re playing music) and that voltage drops by 1/2 and often even more. ` What does this mean to you?  First, when you have less signal going down your RCA cables you need to gain your amp up to get volume and then your system has more background hiss and likely more distortion. An even bigger tragedy is that you are compressing the dynamic range of the music. You lose the difference between the quiet and the loud and the music sounds “canned”. There’s no life in the music.  What’s the answer? A Zapco Signal Line Driver Preamp.  The Zapco ASP-L6 is a six channel line driver delivering a true 9.5 volts RMS of preamp output and 14 volts peak output. With this line driver you can leave your amp gains all the way down and still get maximum power and maximum dynamic range from the amp. Because the line drivers job is boosting the preamp signal, it’s absolutely critical that the line driver does not induce any of its own noise or distortion into the system. That’s why we use only the premium Elna Silmic ll caps and the OP275 audiophile op-amps in the signal path of the L6 and L2 BT line drivers. You also have the option of balanced or unbalanced inputs, and selectable signal ground refrerence. All for a dead quiet, distortion free signal. As a distribution preamp,  the ASP-L6 lets you send 6 inputs to 6 outputs, but you can also send one set of RCAs to all outputs. So you can feed three amps from one set of RCA inputs, or you can send one pair of inputs to 2 amps for mids and highs send a separate bass signal to the sub amp. Finally, the protective cover plate has selectable illumination so you can highlight the installation. Features and Functions  6-Channels in/6-Channels out line driverat 9.5 Volt RMS, 14 Volts peak Distribution preamp configurable for 2, 4 or 6 channels input   Balanced/unbalanced inputs Remote power supply   Remote for channels 5/6 Illuminated logo/cover plate Specifications  THD < 0.01%THD Signal to Noise Ratio > 110dB   Stereo Separation 90dB Preamp Output 9.5V RMS / 14V Peak Dimensions in mm: 190(W) x 39(H) x 135(L) Overall: 190(W) x 39(H) x 164(L)