What's the best approach to add Headphone Amp?

I have a wonderful 2 Ch system consisting of Audio Research CD7, Ref 3, VM220 Monoblocs and Wilson Sophias.
I'd like to add a great headphone amp as well for the times the rest of the house is asleep. My CD7 has both balanced and single ended outputs, with the balanced output connecting to the Ref 3. Should I use the tape out from the Ref 3 preamp to connect to the headphone amp, or is it preferable to use the RCA output from the CD7 while the preamp is off? Does anyone actually have experience with this scenario? Using the Ref 3 provides input switching, but also adds a lot of additional circuitry when compred with a straight run from the CD player to the headphone amp.....Suggestions appreciated.
I have done both and found that straight from the source is the best. Let you system pre influence the external, open environment, and you head pre influence the closed environment.
It depends on the input sensitivity of the headphone amplifier and certainly the sensitivity of headphones.
I use Consonance M20 headphone amp connected to the preamp's tape output driving AKG K701. I found it more refined and controlled than directly from the CD player. In addition I have analogue rig with most of M- records in my vinyl collection that do not produce clicks pops even through the headphones.
To be quite frankly, I would look for better driver than I currently have in the future, but I bet it will still stand great against any speakers.
I'd look for more bass that probably would never get with tubes and aim to some better deals on Grace Design M902 headphone amp.
The specifics of going direct from the CD7 is that the balanced interconnects would be in place, connected to the preamp that is not powered up AT THE SAME TIME AS THE rca interconnects were running from the single ended output into the active headphone amp.
Do you see this as a problem?
No, not a problem.I use a Grace M902 direct from an Audio Aero Capitole Mk II (balanced outs from the cdp into the Grace) and at the same time have the cdp hooked up to a preamp via the rca outputs. Sounds great.
I use a balanced headphone amp plugged into the 2nd balanced output of the preamp...the 1st balanced output goes to my balanced amp for the speakers. When I use the headphone amp, I do not power up the amp for the speakers. When I use the amp for the speakers, the headphone amp is off. I can use both at the same time, but never do.
To my understanding to reach the best performance running directly from the source to the headphone amplifier you should find one with balanced input and balanced bypass so you use fully balanced signal path among your components, but running as you've stated AT THE SAME TIME... isn't a problem.
Grace Design M902 that had been already mentioned is one of the best contenders. You might even want to use it as a preamp vs. the one you currently have.
Could be silly question, but anyway. Should the amplifier have speaker off button in order to listen to music through headphones? Otherwise, the sound will be heard both, through headphones and through speakers. Or Am I wrong? Never had headphones amp. Sorry for hijacking the thread.
Yes speakers can interact with especially open air headphones but technically nothing wrong.
DJs use monitor headphones simultaneously with speakers at the party
A mute switch is very convenient otherwise you don't need to keep your power amplifier on.
I would ask Audio Research first before using the CD'7's RCA outputs. The balanced and RCA's might be tied together.That would change the impedance of the CD7's
output,possibly degrading the sound plus causing other possible problems.I would try the tape RCA outputs from the preamp first since they are made to be used at the same time.
Otherwise,the using preamps tape outputs with the power amps powered down seems like the best option until you find out if the CD'7s outputs are tied together.
Thanks Marakanetz. Very simple and very clever answer.