Superpower = Super Low Noise

Note: Comparison of Belleson SPX with new generation regulators is here.

SPJ78@12V RMS noise voltage measurement

RMS noise of a sample Superpower.

Total unweighted noise across the audio band of 20Hz to 20KHz measures 8µVrms. (see below). This RMS value is noise measured for a +12V out Superpower, which equates to <1PPM of noise per volt out. 3.3V output devices have noise of approximately 4µVrms. Note: Voltage scale was adjusted to reflect a gain of 1000 in the measurement system.

Here is a video of a noise comparison measurement of SPZ78@12V and LM7812:

Also see this editorial discussion of the relative importance of noise compared to other parameters.

Comparison of Six Regulators

Noise comparison of 5 regulators

Noise of six regulators is shown here. These measurements were all made with the same test fixture (above) at the same testing session. Some are common monolithic parts (LM317, LM7812), some are newer, higher quality monolithics and some are "boutique" regulators like Superpower.

A noise spectrum shown below is from a Superpower with 12V out with no external load. Sample rate was 39.063KHz with 4K samples using a Blackman-Harris window. Sixteen sample sets are averaged to smooth the graph.

Superpower noise spectrum

Noise measurements

Superpower noise spectrum at 480mA load

Noise measurement under load

Above is the same noise measurement made with the Superpower delivering a 480mA load. With a gain of 60dB due to the test setup, the measured values were all scaled down by 60dB (= divide by 1000), so, e.g. a value at -60dB became -120dB.

While total noise is slightly higher due to load induced noise, the RMS measurement remains about 8µV and peak-to-peak about 55µV.

To overcome noise floor limitations of the data capture instrument, a low noise preamp with a gain of 1000 is used to boost the noise to be measured:

Noise fixture schematic

Noise is limited to the audio bandwidth of interest by the spectrum analyzer.

Spectrum of measurement system

Test fixture noise floor

Basic noise floor of the measurement system including the gain-of-1000 amplifier shown above. Vertical scale has been adjusted by -60dB to account for the gain.


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The Industry Standard SPX

Order now from our store.

  • 5V to 30V output
  • World's lowest output impedance
  • Superb ripple rejection (135dBV)
  • Instant step response
  • Extreme low noise
  • TO-220 footprint
  • No thermal pad needed!

High Voltage!

Tube lovers—SPHV is BACK!

  • Variable output 5V to 450V
  • Up to 500mA output current
  • Super low 0.5V drop-out at 100mA
  • Small TO-220 footprint!
  • Low output impedance
  • Fast response
  • Low noise

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SPHP—1000 Watts for your music server!

SPHP, a 10A Superpower with adjustable output voltage from 5V to 100V

  • Same low noise
  • Same blazing step response
  • Same great ripple rejection.
Just lots more current and much higher output voltage. For sale on our order page See more information in the data sheet here.

Build a power supply

A PCB and parts list for building a compact dual positive or positive+negative power supply are on this new page.

Transformer Calculator!

Use the Belleson Transformer Calculator to calculate the minimum Vrms voltage of a transformer for your Superpower based supplies.

It's Official

We're proud to announce the U.S. Patent and Trademark Office has granted patent 8,294,440 to the Superpower design.

Use the Superpower regulator in...

  • Headphone amps
  • DACs
  • Buffers
  • Clocks and reclockers
  • Preamps
  • Microphone preamps
  • Phono stages
  • Phono motors
  • Tube preamps and input stages
  • Line powered guitar effects boxes
  • Anywhere an extremely clean, quiet, dynamic power source is needed