Midwest Audio Fest

It’s that time audio enthusiasts! Registration for the 2019 Speaker Design Competition is now open! Visit for details and to list your speaker project. We are excited to see all returning participants, and look forward to meeting some new designers this year, as well! Be sure your plans include a visit to the Parts Express Tent Sale for the lowest prices of the year, and the Audio Swap Meet where you can buy and trade with other audio fans. We hope to see you this summer! Vivian and Jill
See more
See less

Plasma Tweeter

  • Filter
  • Time
  • Show
Clear All
new posts

  • Plasma Tweeter

    First time seeing one....What is the advantages of a plasma tweeter compared to the conventional domes, ribbons etc?

  • #2
    In theory, near zero moving mass so FR can extend up to 100k or so they say. In practice, I don't know. I have never heard one.

    The PEDS 2.1 mini system
    My A7 Project - another small desktop speaker
    The B3 Hybrid Dipole - thread incomplete and outdated


    • #3
      Having heard them myself I’d have to say that the best ribbons easily keep up. The RAAL for example has a moving mass less than the air load on the ribbon.
      R = h/(2*pi*m*c) and don't you forget it! || Periodic Table as redrawn by Marshall Freerks and Ignatius Schumacher || King Crimson Radio

      Byzantium Project & Build Thread || MiniByzy Build Thread || 3 x Peerless 850439 HDS 3-way || 8" 2-way - RS28A/B&C8BG51

      95% of Climate Models Agree: The Observations Must be Wrong
      "Gravitational systems are the ashes of prior electrical systems.". - Hannes Alfven, Nobel Laureate, Plasma physicist.


      • #4
        Originally posted by Unbiasedsound View Post
        First time seeing one....What is the advantages of a plasma tweeter compared to the conventional domes, ribbons etc?

        You don't need a nightlite when they are playing in a dark room. Plasma drivers have some issues. The early one had to be recharged due to dome permeability. There are others too. They are nice, but not the final note in tweeters.

        " Voicing is often the term used for band aids to cover for initial design/planning errors " - Pallas


        • #5
          Roger Russell has a lot of information about early versions of the plasma tweeters--notably the Ionofane and Ionovac products. These early products worked by modulating the temperature of an arc, resulting in a near massless driver. The low mass of the plasma results in excellent burst response. However, Russell points out that the early devices did not have a linear relationship of input voltage to output, and as a result the non-linear distortion was relatively high. He has some distortion measurements on his website, and his measurements show the IM distortion at well over 1%, which is audible. I don't know whether alternate implementations or signal processing of the input can reduce this distortion. Another limitation of this tweeter is that due to the relatively small size of the plasma material output is relatively low. And there were a number of maintenance issues, such as the electrode wear and for some implementations, having to replace gas canisters.

          I heard a nice system with the Ionovac many years ago, and I was impressed. However, I was more impressed by the Heil drivers when they first came out. Those Acapella ION tweeters in the video have fairly high output and claim to be a "perfected" design, but I can't find any details on the design to see how they addressed the IM distortion problem. At $11,000 per pair, I would hope they have much lower distortion than the early plasma designs.
          Free Passive Speaker Designer Lite (PSD-Lite) --


          • #6
            Damn 11k a pair and I thought the RAAL tweeters were expensive lol.....Thanks for every ones response.