There has been some high-level discussion from RAAL-requisite, across different interviews and so on, about what they have in the pipeline.
The two most immediate projects of interest for SR1a/RAAL-requisite fans are the long-rumored circumaural (over-ear) ribbon-drive headphones and the much more recently mentioned tube-based amplifier. RAAL-requisite has a goal of showing both of these new products at the upcoming CanJam in September - though aren’t quite ready to commit to that yet.
Things of note so far …
I don’t know what this will actually be called … maybe “SR1a C” or “SR1c” … or something entirely different.
Current commentary has it targeting a $2,900 (or lower) price-point. It will use a shorter ribbon than the SR1a, though no word on whether it is wider and/or has greater/lesser surface area. Native bass reproduction should be flat to 30 Hz. And the cups will be setup such that they are angled relative to the ear by 15 degrees, which should help preserve some of the SR1a’s much-vaunted ability to image and stage in a speaker-like fashion.
I’ve heard this referred to as the “VM1a”, tubes mentioned were 6LZ for signal and EL34 for power. A single-ended, push-pull design (single-ended means it should retain more tuber-goodness than a balanced design would do), with a currently projected price of $6,500.
I am likely in for one of each … especially if the VM1a ups the available power for conventional headphone and speaker drive (assuming it retains both those capabilities from the HSA-1b … which I’ve not heard anything about).