Purity Basis mkII
Class 'A' 6SN7 or 12AU7 Vacuum Tube Linestage

Simplicity, Elegance & Value

Exceptional dynamics and speed with the richness of the 6SN7 dual triode
from this enhanced Basis MKII linestage in a single aluminum chassis.

The Basis mkII offers single ended audiophile quality in a simplistic design
without any bells and whistles to rob sonic purity.

The Basis Series is being discontinued. A new, more advanced model will be released soon to take it's place.
Now is your chance to save on the remaining inventory. Your choice of tube or solid state power supply.

Any feasible option you may desire. Contact us to discuss custom building one of these last remaining options to fit your personal needs.

 Remaining units: 3  2 pieces available

Clearance Price $3,750


The 'Basis' provides a silky smooth, clean,  dynamic presentation with low distortion using a Class 'A' zero feedback circuit providing a low output impedance and high input impedance. If you have never heard the virtues of a 6SN7 based preamp, especially one designed by Purity Audio Design, you do not know what you are missing. Don't let the affordable cost or simplistic design of the Basis MKII fool you, this is a piece that is very much at home in the most elaborate audiophile systems and decors. This affordable tube preamplifier maintains the dynamic quality of all types of music. You have the option of running 6SN7 tubes or with our adapters, you can run 12AU7 type tubes with no more than simply installing the adapters.

The sound of the Basis mk2 is has a better sense of refinement and dynamic impact at the frequency extremes with a kiss of emotional warmth. Like all Purity Audio Design products, the Basis mk2 provides a dead quiet background allowing you to enjoy and appreciate the finest nuances hidden within your recordings along with a broad soundstage positioning you in the center of the performance.

The Basis mk2 a GoldPoint step attenuator, 4 line level inputs and two sets of RCA outputs that are perfect for bi-amping or driving a powered subwoofer.  A standard feature in the Basis mk2 is a newly designed choke filtered power supply for a background as black as the deep reaches of space. A new highly regulated supply is now implemented for the tube heaters/filaments.

The circuit design places very little stress on the tubes assuring extremely long service and sonic life of the tubes. Quality, Value, and Performance, by Purity Audio Design and like all Purity products, hand made in New York, USA. .

The Basis II comes standard in an aluminum chassis with laser engraved front panel markings.

 The Basis is available for world wide sales and can be configured to run with the following mains voltages: 110V- 117V or 220V-240V. Primary voltages are factory wired so let us know what voltage arrangement you need at time of ordering.

Recommended Tubes:
After extensive testing and listening, Purity Audio Design has determined the Sophia Electric 6SN7 tube to be among the very best in current production. To make life easier for you, we can now offer you the Sophia Electric 6SN7 and/or 12AU7 tube with your order of a Basis mk2 for an upcharge.

Power Supply - Solid State

  • A large high current toroidal transformer
  • Separate power transformer and DC power supply for remote control system
  • Choke filtered power supply
  • Polypropylene power supply filter capacitors
  • StealthTM (Ultra Fast) diodes used throughout.




  • Aluminum chassis

  • 100% polypropylene power supply

  • Choke filtered

  • High current Toroidal transformer

  • Laser etched aluminum front panel

  • 6SN7 or 12AU7 compatibility

  • Goldpoint Step attenuator

  • Aluminum control knobs

  • Finish: Black anodized


  • Circuit: Class A zero feedback
  • Freq. Response: 20Hz-- >750kHz
  • Input impedance: 50K ohms
  • Output impedance:
    High Gain: 20dB
    Low Gain: 15dB
  • Output impedance:
    High Gain - 450 ohms
    Low Gain - 750 ohms
  • Phase: Inverts
  • Tubes: 2x 6SN7 or 2x 12AU7
  • Size: 16.25" W x 12.25" D x 3" H
  • Net Weight: 13 lbs.
  • 3 year parts and labor warranty
  • Suggested Retail Price: Contact Us

Please see our Product Comparison Chart to help you in making the proper decision for your system goals.

Factory upgrade options: Contact us for pricing.

  • Dynamicap, V-Cap OIMP or Clarity MR output capacitors

  • V-Cap TFTF or CUTF bypass