S-30 Mk. 3.2
stereo music amplifier 
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 audiophiles who seek the ultimate in amplifier design and are realistic about their budget, the S-30 gives you the same precision and sound quality that Atma-Sphere is known and recognized for. Featuring automatic bias and a large VU meter, operation is elegantly simple.

And because it utilises decades-proven patented handwired circuitry, it is stable with any load and both performs and sounds better than any single-ended amplifier ever produced, let alone conventional push-pull designs. Its fully-balanced design and proven class-A triode operation make the S-30 the ideal choice for the discriminating audiophile.
  • Balanced Differential Design®
  • Class-A operation
  • Patented Circlotronic® direct-coupled (OTL) output stage
  • Dual-mono chassis construction
  • Automatic bias - no adjustment needed
  • Built in VU meter for tube and output monitoring
  • Easily monostrapped for greatly increased power
  • Uses only one gain stage for supreme clarity of sound
  • Proprietary precision components used throughout
  • Low-noise "star" grounding topology
  • Fully hand-wired point-to-point electronics - no circuit boards!
  • Stable with all input and load conditions
  • Exclusively uses Octal-Triode based vacuum tubes
  • Classic open chassis construction with Wrinkletex™ finish
  • Three-year general coverage warranty, one year warranty on output tubes

Output power

30 watts per channel into 8 Ω load
45 watts per channel into 16 Ω load

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

Gain

23dB ( for 8 Ω )

Power Bandwidth

2Hz-75KHz within ½ dB

Frequency response

( 1 watt, open loop ) 20 Hz squarewave Tilt; unmeasureable
1Hz-200KHz within 3 dB

Hum and noise

Less than -75db below 1 watt, -95db below full power (30 watts)

Distortion

Total Harmonic Distortion ( THD ) typically 1% at full power
Intermodulation ( IM ) distortion typically under .04% at full power
Phase shift less than 1° @ 20KHz

Output section risetime

600 V/µs

Feedback

2 dB

Power consumption

400 watts

Dimensions

13" deep x 17" wide x 8" tall ( 33 x 43 x 20 cm )

Weight

( without tubes ) 24 lbs ( 10.9 kg )

Warranty

Three year general coverage
One year for output tubes

AudioReview.com

Various, user submitted 

Extreme AV

Vangelis Lazarou (in original greek)
Page 1Page 2Page 3Page 4

Revue Du Son Et Du Home Cinema

Jean Hiraga & Robert Lacrampe, October 2002 (in original french)
Page 1Page 2Page 3
For all support requests, or any questions about your Atma-Sphere product, contact us directly at (651) 690-2246 or send us an email.

Optional Features

Power Supply Boost option
V-Cap Teflon® coupling caps
V-Cap Copper Foil Teflon® coupling caps
Caddock® resistor package

Meter Panel finish options

Gray hammertone
Brushed anodized black
Brushed anodized silver
Brushed anodized gold
Custom finishes available upon request

Accessories

Jumper plugs for high efficiency speakers
      Replaces tube in the voltage amplifier section of Atma-Sphere
      power amplifiers, thus reducing gain for high efficiency speakers.
      Recommended when efficiency of speaker is over 100.


Cables

Balanced Interconnects
Balanced phono cables
      1 meter, DIN to XLR or RCA with ground post to XLR

Pricing

Contact your local dealer for pricing information.
Or, call (651) 690-2246 or email us with any questions.