"The more the wings angle out, the more the loudness differential equalizes because cancellation grows more effective. In the far-field you'd have a 6dB roll-off below 2kHz. When positioned close enough so that the panels don't touch your ears, the response is flat down to the driver's Fs. Actually it's a bit lower since radiation resistance increases some toward DC due to the limited space between driver and head. Of all possible headphone transducer technologies, ribbons are the only true bass transducers because we can set a ribbon's Fs anywhere from 10Hz on up. We chose ~36Hz as the best balance between power handling and bass extension. That's why we don't need to seal our ribbons with circumaural ear pads to get true bass. As a 2nd-order system, roll-off below self resonance is 12dB/oct. but due to the proximity effect's EQ it's actually slower than that."

Reader Russell Dawkins: "I talked to Requisite's Danny McKinney yesterday. Apparently the Schiit Jotunheim R for the Raal SR1a ribbon ear monitors is coming out in two versions: one with Schiit branding in their own case, the other in a case designed by Requisite with Requisite branding. Their model name will be FOS for 'full of schiit' because the internals are identical. Pricing for the whole package will be minus $300 for eliminating their Raal interface box and +$800 or $1'000 for the amp with and without USB inputs, so $4'000 and $4'200 for the two headphone/amp packages from Raal Requisite. This will strain my budget a little but I think I'll do it." Russell does recording and mastering. He's eternally fighting his room's influence over his monitor speakers. It limits how much he can trust his final mixes. Ultra-premium headfi with earspeakers particularly made for his job would connect him most directly to his tracks.

Driving SR1a with $9'000 COS Engineering D1 DAC/pre and class A $6'500 Pass Labs XA-30.8: fabulous sound but gratuitous overkill considering

Circling the wagons has arrived us at today's R-rated machine – a volume-controlled amp with optional USB DAC designed exclusively to drive Raal's ribbon headphones.

If that's not what you intend to plug in, forget all about it. Period!

If that's what you do intend to plug in, forget all about big expensive speaker amplifiers, the interface box and perhaps even a standalone DAC. Three periods?

The standard Jotunheim is a $399 headphone amp capable of swinging 7.5wpc balanced into 16Ω. The SR1a want about one watt into a near dead short with high current. That revisits Apogee's Scintilla, yesteryear's infamous panel speaker which ate amps for breakfast except Krell. So 'R' has to do its thing different than standard Jotunheim. Completely different.

The optional DAC module at right of course is the same C-Media CM6631A USB transceiver feeding an Analog Devices AD5547 DAC with Schiit's proprietary DSP filter. It all fits into 9" x 6" x 2" and weighs 6lbs.

That's small enough to fit on a desk top, portable enough to fit into a carry-on bag to accompany an extremist listener on vacation or a recording engineer on location. It takes up seriously less room than our twin Kinki setup, weighs next to nada compared to a big Pass amp and saves considerable coin. That I just had to hear for myself even if it meant buying one unheard. Why?