This is one of the best integrated amps you can buy even at many times the MSRP price of $9500.
Krell K-300i Integrated Stereo Amplifier For Sale - US Audio Mart
I used to own the Meze Empy with Benchmark HPA4 headphone amp. I thought it was great. However, after I had the RAAL SR1a for a few months I realized I was never going to listen to the Meze again. I sold the Meze and the HPA4.
The KRELL integrated is, in my opinion, the very best of the best for the RAAL SR1a headphones. I have tried a lot of 2 channel amps and the dedicated RAAL headphone amp. In fact, I bought the KRELL Duo 175XD last month specifically for the RAAL SR1a in my office. This was based solely on how good the SR1a was on the K-300i.
The way it would work is that RAAL will provide an AMP INTERFACE BOX with the headphones. You can use a 2-channel amp to drive the headphones and this box has a switch to send the output of the integrated to the 2-channel speakers. You would need 2 sets of speaker cables to do this. The supplied speaker cables by RAAL are not good. I have not used the switch to change from the headphones to the speakers. I have a more elaborate setup. However, the only potential negative would be the extra path to the speakers. The headphone path has to exist anyways.
The KRELL integrated will have built-in streaming, ROON READY, DAC, HDMI for TV and Bluray. The sound is very smooth, good detail, and very relaxing and non-fatiguing. Normally not my kind of sound but I am now hooked on it.
You would just need an Ethernet wire from your network to hookup to the KRELL. Hopefully a ROON account and you are ready to go. If you do not have Ethernet nearby (I do not in my setup) you can use a PowerLine extension to your home network to work via the electricity outlets in the room. This is how I have setup my KRELL. Though I am somewhat technical and know how to fix these things if the network ever has a hiccup. It usually happens when things are moved around or unplugged.