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The 250 pieces batch of IN-9 Nixielyzer is now sold out, but...

At the beginning of 2020 I will release another small series of pre-built Nixielyzer again, as there is still an unbroken interest.
But also for this there are not negligible pre-financing costs and delivery times (tubes, enclosure, PCBs, special electronical components).
This time I don't want to go via Kickstarter, but to realize the pledge with PayPal, because there are much less fees to pay.
Thanks to the the PayPal buyers protection your payments are secured for 180 days. However, at least 20 backers should come together so that a new edition pays off.

If you want to get a complete IN-9 Nixielyzer incl. Neon bargraph tubes in spring 2020, you can contribute to the financing of "your" Nixielyzer as follows:

For Germany and EU:
For export to Non-EU countries:

Current number of backers: 0

Should a corresponding number of backers not come together by the end of January, your money will of course be re-founded.

But remain curious for early 2020; there is something new in the pipeline, true to the motto: "Bigger is Better"... an IN-28 VU meter

The IN-9 Nixielyzer is an analog audio spectrum analyzer, based around the BA3830F analog analyzer chip. It offers the display of six selective audio bands: 63 Hz, 150 Hz, 330 Hz, 1 kHz, 3.3 kHz and 10 kHz.

As an extra feature, you can mix the signal of a build in microphone to the display, to use the IN-9 Nixielyzer as a stand-alone device when no audio source is connected).

The IN-9 Nixielyzer operates with six IN-9 Nixie Bargraph tubess and has two RCA stereo in- and outputs (for easy daisy chaining the device within an existing audio path) and also two 1/8" TRS jacks for simple connecting your MP3 player, mobile phone plus headphone for listening etc.

Both signals (RCA and 1/8" TRS are only internal mixed via an electronic zero ohms node and do not affect each other.

The IN-9 Nixielyzer uses no digital signal processor or FFT (Fast Fourier Transformation); so the display is stepless and fully in realtime.
Furthermore a modified dbx compandor ciruity was introduced to enhance the dislayed dynamic range.
The topology of the electronics corresponds to that of the proven EM800 Magilyzer circuity.

Video Review from "Techmoan"

Assembling the kit and circuit description from "youtuuba"

What is an audio spectrum analyzer?

You surely know a VU meter, which shows the level of an audio signal, often build with LEDs on the DIY market.
The IN-9 Nixielyzer now separates this audio signal into six selective bands and show their special audio level within this frequency range:

• 63 Hz = Low Bass (e.g. Bassdrum)
• 150 Hz= Mid Bass (e.g. Bassguitar)
• 330 Hz = Low Mid (near concert pitch of the most musican instruments)
•1 kHz = Mid of voice frequency (e.g. the "beep" sound for indecent words in interviews)
• 3.3 kHz = Presence (e.g. "sch" in the word Schedule or the imitated sound of a steam locomotive)
• 10 kHz = Heights (e.g. "sssss")

And as an absolute unique feature, the IN-9 Nixielyzer displays the level not on "ordinary" LED display or VFD display or on a computer screen or even in an App of your mobile phone but on six IN-9 Nixie Bargraph tubes made in the end of the 80's in USSR as a surplus.
You'll get a fully complete DIY kit and complete means complete:
PCBs with double sided silk screen
All necessary electronic components
All necessary mounting hardware
Complete enclosure with all necessary covers
15 VDC wall mart power supply with EU mains incl. adaptors for US/GB/AU is included
At your choice Aluminium frame black or silver anodized
On request 1 set of IN-9 tubes (optional with Argon = pink or Neon = amber inert gas)
On request spare tube(s)
On request extra front frame to hide all controls


  • 15 VDC power supply included
  • No self generated heat
  • Stereo RCA in- and outputs for easy daisy chaining in an existing audio path.
  • Two 1/4 TRS stereo inputs as an alternative for MP3 player, mobile phone, headphone etc.
  • Selectable audio channel (right / both / left) for display.
  • Build-in microphone signal can be mixed.
  • 63 Hz, 150 Hz, 330 Hz, 1 kHz, 3.3 kHz and 10 kHz audio spectrum level are displayed.

What you'll need:

  • 4 hour of your evening time with no hurry
  • A clear, well-lit area in which to work
  • Soldering station and fine electronic solder
  • Multimeter to check the generated voltages
  • Electronic tools
  • A loupe may be helpful
  • TX10 (Torx) and slotted screwdriver
  • Download of the manual
  • Enjoyment of your work of course
  • 6 x IN-9 tubes (offered separately)
  • A line audio source or simply use the build in microphone
  • Dimensions (W x D x H): 135 x 95 x 160 mm incl. tubes
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