From Suhr:

The PT15 I.R. is the world’s first truly hybrid amplifier, marrying classic tube circuitry with a reactive load and digital impulse response technology.

With the PT15 I.R. we set out to combine the strengths of both analog and digital to create something new. The addition of a built-in Reactive Load and on-board impulse responses, make using a speaker cabinet optional for recording, or feeding front of house with a studio quality mic’ed up tone. Also included is a headphone output and auxiliary input to practice and jam along with your favorite tracks, wherever you are.

The all-tube three channel design offers a plethora of American and British tones, powered by a new 6V6 driven power section. The dynamics, overdrive, saturation and harmonics that we crave as tonal purists, is all here. By adding channel assignable IRs, you now have unprecedented versatility and control over your tone, expanding your choices more than ever before.

Channels: 3
Output: 15 watts
Front Panel: Input, Aux Input, Headphone Input, IR Level, (CH1) Bright Switch, Gain 1, Bass, Treble, Level 1, (CH 2/3): Bright 2/3 Switch, Gain 2, Gain 3, Bass, Middle, Treble, Level 2, Level 3, Channel Select Switch, I.R. Bank Select Button, I.R. Cab Select Button, I.R. LEDs, Power & Stand By switch.
Back Panel: H.T. Fuse, Mains Fuse, Mains Input, Reactive Load Parallel Output, Reactive Load Disconnected Output, Impedance Selector, FX Loop Send, FX Loop Return, Footswitch (TRS) jack, Balanced/Unbalanced Line Out, I.R. Filter Bypass Button, USB Jack.
Tubes: 2 x 6V6GT (Power Section), 5 x 12AX7.
FX Loop: Tube driven, buffered
Mains Fuse: T1.5A/250V (Slo-Blo) - 100/120VAC, T.75A/250V (Slo-Blo) - 230/240VAC
H.T. Fuse: F.5A/250V (Fast-Blo)
I.R. Format: .WAV, Mono, 24bit, 48kHz, 20.5 ms (I.R.s greater than 20.5 ms will be truncated to 20.5 ms)
I.R. Output Latency: 1.2 milliseconds
Dimensions: 20.5" (W) x 8.25” (D) x 9.25” (H)
Weight: 24.7 lbs.