Atma-Sphere - MP-3 Mk. 3.3


[Contact us for a price]

In stock

Minimum quantity for "Atma-Sphere - MP-3 Mk. 3.3" is 1.


MP-3 Mk. 3.3

Music Preamplifier

Features :

The MP-3 preamplifier is based on the concepts pioneered by our MP-1 preamp, now in a single-chassis package. Recently updated to Mk 3.3, the MP-3 is a fully differential all-tube preamplifier, with a direct-coupled high current output capable of driving low-impedance balanced-lines. Like our MP-1, the MP-3 easily drives interconnects over 200 feet long! The MP-3 extracts more ambient information with greater image specificity, bass definition and dynamic range than any single-ended preamplifier. Furthermore, it perfectly complements the balanced design of our Music Amplifiers or any balanced power amplifier. The patented innovations, developed specifically for this preamplifier, have allowed the MP-3 to rise to the top.

Balanced line technology has been in use in the recording and broadcast industry for decades, and is why the high fidelity era began in the early 1950s, long before exotic interconnects existed. Balanced lines work better than single-ended cables, being dramatically more resistant to RF, hum, cable artifact and cable length. In essence the low impedance balanced line system is a means of preventing your interconnect cables from affecting the sound of your stereo. The MP-3 supports this system, so you can run long cables with no need for exotic interconnects.

In addition to its remarkable line section, the MP-3 works well with low-output moving coil cartridges and uses a minimum of connections in the front panel wiring and controls. A low number of gain stages (only three from phono input to line level output) insures the low distortion, wide bandwidth and superb dynamic range. The result is a truly musical package with exceptional value.

  • Balanced Differential Design®
  • XLR connectors for phono and auxiliary inputs
  • XLR output connections
  • Patented direct-coupled Circlotronic® output
  • Zero feedback design throughout
  • Balanced differential passive phono equalization
  • Precision 23 position stepped volume control built with 96 resistors on a custom built switch
  • Two tape monitor inputs, tape functions use RCA jacks
  • Precision components used throughout
  • Total system phase switch
  • Low-noise "star" grounding topology
  • Three-year general coverage warranty with one year warranty on output tubes

Specifications :

Line stage frequency response

1 Hz-200 KHz, +0 dB, -2dB

Line stage gain

15 dB

Line stage input impedance

100 Kohm Ω single-ended / 200 Kohm Ω balanced

Line stage output


Output impedance

250 Ohms from 2Hz to 400KHz

Phono stage input impedance

47 K Ω, adjustable with rear panel loading strip

Phono stage input overload

500 mV

Phono stage max output

( at clipping ) 120 V peak-to-peak

Phono stage gain

55 dB

Phono bandwidth

.5 Hz-90 KHz within ½ dB

RIAA accuracy

Within .1 dB

RIAA Phono sensitivity

( for 0.5 V @ 1 KHz ) 0.2 mV

Power Supply storage

50 Joules

Tube complement

7 x 12AT7
2 x 6SN7GT
2 x 12AU7


13" deep x 17" wide x 5.5" tall ( 33 x 43 x 14 cm )

Faceplate dimensions

( standard 3U rack, sans mounts ) 19" wide x 6" tall ( 48 x 15 cm )


19 lbs. ( 8.6 kg )