The S-30 is the unchallenged state-of-the-art in low power vacuum tube amplifiers. With its simplicity of operation, small footprint, and all the features of our larger amps, the S-30 represents the high-water mark of compact OTL design.

For those who seek the ultimate in amplifier design the S-30 gives you the same precision and sound quality for which Atma-Sphere is known. Featuring automatic bias and a large VU meter, operation is elegantly simple.

The S-30 utilises decades-proven patented handwired circuitry so is stable with any load. It performs and sounds better than any single-ended amplifier; a nice choice for a loudspeaker that does not need high power. Its fully-balanced design and proven class-A triode operation makes the S-30 the ideal choice for the discerning audiophile.

You'll see the amp is in excellent condition. It's a MK3.2 version and was upgraded with V-Caps some time ago. To be sure that the amp is in top condition, I shipped it to Ralph Karsten at Atma-Sphere for a complete check out. Ralph checked and verified all the tubes and also replaced two filter capacitors and two resistors in driver power supply. It will be shipped directly from Atma-Sphere.

Output power 30 watts per channel into 8 Ω 45 watts per channel into 16 Ω

Impedance Input Impedance: 100 KΩ single-ended, 200 KΩ balanced Output Impedance: 7 Ω

Input 3 V sensitivity RCA and XLR true balanced input

Tube complement 10 x 6AS7G output tube 6 x 6SN7 driver tube