Double Blind Feature

Hey there.

I’ve been following PS Audio for a few years after finding Paul’s videos. I joined the forum for another reason, but in poking around here I came across people saying that power conditioning is pure magic, and the most important thing in their system.

I realized that, if these $2200+ power conditioners really are magic, then there’s an excellent way to convert skeptics like me: Add an optional double blind test feature. Just offering the double blind test feature would sell units. Combined with testimonials confirming that the test was convincing, it would demonstrate enormous brand confidence, and the test itself would become a formality for many people.

PS Audio could add it to a limited SKU produced internally for demo/loaner units. However, I like the idea of a special Skeptic Edition line. Add an up-charge, maybe $200. They could even charge less than the manufacturing cost and write off the loss and development costs as advertising. Confident buyers could save a little money, while skeptics have 30 days and can end the trial with full confidence that they weren’t just fooling themselves about the differences. It would be money well spent in my book. Plus, I’d consider the Skeptic Edition a badge of honor, and I’d love letting skeptical friends and family run the test even years later.

How would it work? There are lots of options, but here’s a super basic one:

  1. Add the Skeptic Edition badge to the unit, this is critical :smiley:
  2. Include a small outboard box with a little LCD/eink display, 1 button, and a 1/8" mini jack (Include a 4 meter 1/8" stereo headphone cable).
  3. Add a bypass circuit to 1 of the power outlets. If enabled it bypasses the regenerator and provides unprocessed wall power. Clearly, this is critical path. It can’t affect the regenerated power or the wall power. Ideally, it should toggle between them without causing upstream issues. There’s a risk that aligning the waveforms during a switch will be essential but difficult. It should be possible to delay until they have a synchronized zero crossing, but this is an area that would need some engineering work to figure out. Worst case, you make the user turn off the down stream device between tests.
  4. Add a 1/8" jack to the regenerator with a simple circuit board to provide power to the outboard box and enable/disable the bypass circuit based on serial commands.
  5. User: print out a form with instructions and a record sheet
  6. User: choose a device and connect it to the test outlet, connecting the rest of the components either to the wall or regenerator as desired.
  7. User: Press the button to start the test.
  8. Box: Secretly, randomly choose regenerated or bypassed (wall), toggle test outlet, and store the choice. (Ensure that there is no cue about if something changed. For example, if the bypass circuit includes a mechanical relay that clicks audibly then include a dummy relay and trigger it if there was no change to the actually bypass circuit.)
  9. Box: Display: Test 1 Ready. Press button when done.
  10. User: Start some audio. There are a number of different ways to run the test, with different pros and cons, and the instructions could suggest some good ones, but I won’t discuss that here.
  11. User: Press the button when ready for the next test, the box reconfigures the outlet randomly.
  12. Box: Display: Test 2 Ready. Press button when done.
  13. User: After test 2 note “better”, “worse”, or “same” by circling one on their test form.
  14. Repeat.
  15. User: Press and hold the button for 4 seconds to end the sequence.
  16. Box: Displays the settings

Test Results (R - Regenerated, W - Wall)
1R 2W 3R 4R 5W 6W 7W 8R 9W 10W

  1. User: Record settings in blanks provided on the test print out.
  2. Data is stored in non volatile memory, so the user can resume where they left off at any point if they accidentally disconnect the cord.
  3. User: Hold the button for 4 seconds to clear the test sequences and start over. They can perform the test again

The user can clearly see if they consistently noticed real changes.

This would be a fun project to design and manage. Anyone could do the software, though a dev that knew the SOC could do it faster, and QA would be trivial. It would require a little time from an EE, and even less time from an ME to refine the housing and changes from the base product.

It could get a little or a lot more complex. An obvious change would be adding more outlets, though that’s more difficult to develop, costly to produce, and the results get more difficult to interpret. It would be great if you could randomly toggle power to your preamp, dac, mains amp, and subwoofer separately, but a beastly long test and I wouldn’t expect most people to easily grok the data.

At the other extreme, PS Audio could add WiFi connectivity and make a slick web interface or an app. They could even let users upload their results into a pubic listing on their website, including their Forum Name, and the involved components. This option would obviously involve a more software and a lot more QA time.

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