Raptor007
New Head-Fier
Happened to find this thread while figuring this out. Since ChillToMusic already bumped it this year, figured I'd reply with my solution.
I just got the iFi Zen CAN headphone amp, and intended to add it to my setup while continuing to use a Marantz SR5005 AV receiver to switch inputs, drive my speakers when desired, and otherwise act as DAC for the Zen. Frustratingly, the receiver thwarted my initial attempts to use any of its RCA outputs for this. As my input signals are both optical digital, the Marantz manual revealed why [p.41]:
The solution I arrived at is to just connect the headphone amp to the AV receiver's headphone jack, with the receiver's headphone output volume somewhere around -36dB. As you suggested, you could do this by adapting the 6.5mm to dual RCA. In my case the ifi Zen CAN has a 3.5mm input, so I just used a short 3.5mm cable with a 6.5mm adapter on the end going into the AV receiver's headphone jack.
This actually turned out perfect for me. It retains the nice feature that plugging/unplugging the headphone amp from the receiver's headphone jack automatically mutes/unmutes the speakers. It also lets me use the AV receiver's bass/treble tone controls for the headphone jack without applying those settings to the speakers. I haven't done A/B testing yet (maybe this weekend) but my initial impression is that the sound is improved in clarity and impact with the amp, and that's not even using its XBass or 3D enhancements.
I just got the iFi Zen CAN headphone amp, and intended to add it to my setup while continuing to use a Marantz SR5005 AV receiver to switch inputs, drive my speakers when desired, and otherwise act as DAC for the Zen. Frustratingly, the receiver thwarted my initial attempts to use any of its RCA outputs for this. As my input signals are both optical digital, the Marantz manual revealed why [p.41]:
It is not possible to play the digital audio signals input from the
HDMI, COAXIAL or OPTICAL terminals in ZONE2. Play using analog
connections (in stereo).
The solution I arrived at is to just connect the headphone amp to the AV receiver's headphone jack, with the receiver's headphone output volume somewhere around -36dB. As you suggested, you could do this by adapting the 6.5mm to dual RCA. In my case the ifi Zen CAN has a 3.5mm input, so I just used a short 3.5mm cable with a 6.5mm adapter on the end going into the AV receiver's headphone jack.
This actually turned out perfect for me. It retains the nice feature that plugging/unplugging the headphone amp from the receiver's headphone jack automatically mutes/unmutes the speakers. It also lets me use the AV receiver's bass/treble tone controls for the headphone jack without applying those settings to the speakers. I haven't done A/B testing yet (maybe this weekend) but my initial impression is that the sound is improved in clarity and impact with the amp, and that's not even using its XBass or 3D enhancements.