Can I bi amp my B & W 603 S3 speakers with an

Unless you can configure the processor portion to direct each side of the stereo signal to two of the amplificatin channels (unlikely), the anwer is no.

I have a friend doing that with B&W's and a Marantz receiver but don't know about Arcam.

Thank you for the responses. The used Arcam AVR 250 is $1,100.00 at a local Arcam dealer and it would be a good upgrade compared to the $400 Yamaha AV receiver I am using. I may buy it and use only 5 channels or keep looking. Thanks. (Two channel is more important to me than the ability to watch movies).

I am bi-amping my Arcam AVR300 using channels 6&7 under "advanced settings" for my B&w 604s3's with a considerable difference in performance. Stereo Direct in 2 channel mode to my Arcam CD36 CDP with Kimber 1030 IC is a terrific way to get the most musicality out of my setup.
Good luck

Thank you everyone and Evergrey. In the stereo direct mode does the AVR 300 use only the 2 channels for the main speakers and not channel 6&7? Is the Kimber 1030 IC the interconnect between the CD player and the Arcam AVR 300? I am going to purchase an Rega Apollo CD player in the next month (they are sold out), do you see any problems with the Rega brand and the Arcam receiver? Thanks. I am going to look at the Arcam AVR 300 or AVR 350.