Plasma speaker

Anyone else made one?

Here's mine! I used the flyback driver that Le Quack and Sigurthr helped me make. It's still a WIP:

Thanks!
I just started building HV stuff this year, this and the Arduino are my current obsessions!
Gotta find a way to combine them and lasers on the same device XD

I'v been eyeing kits of these for quite a bit now. The basic building doesn't seem to be to difficult, but there is a controlling circuit that I don't completely understand.

You've got a good start there though. Perhaps you would keep this thread updated and with lot's of nice photo's!:beer:

532 with Envy said:

I'v been eyeing kits of these for quite a bit now. The basic building doesn't seem to be to difficult, but there is a controlling circuit that I don't completely understand.

You've got a good start there though. Perhaps you would keep this thread updated and with lot's of nice photo's!:beer:

Click to expand...

this and maybe a schematic?

Nice work! Ive wanted to make on of these for a while.

Thanks guys!

I also don't understand the whole thing but I'm learning a lot about electronics while doing it

It wasn't as difficult to make as I expected, probably because I had a lot of help from the guys here with the flyback and from the author of this instructable with the audio part. My circuit is a bit different from his, I'll post the schematics in a few days, just want to make the the pre-amp as nice as possible before moving it inside the driver box. He mentioned he's having trouble with blowing MOSFETs so if you guys give his version a shot I'd suggest to add a fan to the MOSFET heatsink.

The hardest part was getting the flyback itself "ready". That took a lot of trial and error, plastic cutting and hot glue... and it's hard to make a tutorial because each flyback is born different :/


Edit: since you guys want to see the progress.. here's a video of the previous version, controlled by an Arduino with a preprogrammed song from the game Ultima Online. It was very distorted and weak, dial the volume up!

http://forum.allaboutcircuits.com/cache.php?url=http://teravolt.org/Plasma_Speaker_2_files/schem.png

Use this, instead. A half bridge will withstand a lot more abuse than just a single mosfet.

Nice Plasma speeker , heres My one , PLL Half bridge desing ,

Power Draw is around 1 amp @ 230V supply ,been a hlaf bridge the flyback primary sees half that voltage .

Its playing mario 8 bit , But will play normal music fine

Half Bridge Flyback Music - YouTube

here's mine:

http://laserpointerforums.com/f60/my-plasma-speaker-71625.html

Very nice! Glad to see you got it working well after all.

I'm on the Tesla Coil side of the plasma speaker fence now, and things are MUCH MUCH more complex, heh. Eventually I'll have a video up. For now, I've made an audio modulator that works decently, but sound quality isn't great and volume is low. It isn't very easy to fully modulate a 1.5kW RF signal with a couple mW of audio. Current status is that I'm in the process of redesigning my SSTC driver with alternative ICs which eliminate the need for a 5V rail, and also finding a method for increasing the primary side reactance by at least double while keeping the DC resistance low. As for the actual modulator it is just a Class-D amplifier driver used as an interrupter.

Basically this is how my TC modulator works:
TC Driver: a schmitt trigger receives the E-field from the secondary and squares up the waveform which is then fed in to a UCC gate drive chip pair which then drives the half/full bridge which powers the primary. This way the primary is always driven at the resonant frequency of the secondary.

The audio modulator: is a SG3525 which varies the pulse width of the TTL signal applied to the enable pins of the gate drive chips which turns them on and off. Unfortunately you have to set a pulse frequency for the SG3525 that is <400KHz and it just varies the pulse width with the frequency staying locked at whatever value is set by RC components. The problem is that pulse frequency modulation is the optimal method of modulating a Tesla Coil, and not Pulse Width Modulation. If you could set pulse frequency to that of the audio frequency and lock pulse width at a desired value you would have a truly perfect Tesla Coil audio modulator giving you high fidelity and variable volume (pulse width) control. With PWM modulation the volume of the audio output is locked as the average power produced by the average pulse width, which is quite low.

I might try a half bridge but I'm more inclined to go Fiddy's and Sigurthr's route with a Tesla Coil. I've been wanting to build one for years but never got around to it, mostly due to the difficulty in finding a NST here.

ionlaser555: Nice one, huge arcs. What's the output voltage? I noticed you have to draw the arc from a very close distance.

Atomicrox : Thanks , Hm the voltage is pritty high i belive maybe 15kv ish DC , out of shot the was a smaller arc to load down the transformer other wise i get a massive voltage 20Kv + and hissing every wear .


This is my STTC speeker verstion

Draws about 1.4 Kw When running CW , 230V Half bridge desing , uses secondary feedback / PLL

Audio Modulated SSTC Test 1 . - YouTube

Ignore My rambling ..... Music starts at 1.44 into video .

And This is my VTTC verstion

http://www.youtube.com/watch?v=LPY-a_NH5cs&feature=relmfu

I like the direct modulation of the power to a ZVS driver. Only one extra component :beer:

You have one of the driver's power rail going through the 12V side of a relatively big transformer. You then just feed an audio signal into the 120V side. I used a transformer out of an old UPS.

Cyparagon said:

I like the direct modulation of the power to a ZVS driver. Only one extra component :beer:

You have one of the driver's power rail going through the 12V side of a relatively big transformer. You then just feed an audio signal into the 120V side. I used a transformer out of an old UPS.

Click to expand...

Yeah I Like that idea too works pritty well

Audio Modulated ZVS driver on 30 Volts - YouTube

I used a old 240V to 12V Tranformer to inject the audio into the ZVs supply ( Smooth DC )

That VTTC's arc is very cool, never seen one like that before..

What do you guys mean by injecting the audio into the 120/240V side?

Atomicrox said:

What do you guys mean by injecting the audio into the 120/240V side?

Click to expand...

The output current of the driver is proportional to the input voltage. The size/temp of the arc is proportional to the current, so the arc shrinks and grows with the signal, producing sound.

Cyparagon said:

The output current of the driver is proportional to the input voltage. The size/temp of the arc is proportional to the current, so the arc shrinks and grows with the signal, producing sound.

Click to expand...

Wouldn't it be more beneficial to make it a step UP transformer for the audio transformer?

That way the noise is a bit more pronounced, you know?

And ZVS drivers aren't necessarily the best for plasma speakers, mainly due to that they don't produce AS much of a step up in regards to voltage. They're mostly for the high amount of current they produce, hence why the arc is much more like a flame rather than a blue-violet arc.

Using a true flyback transformer driver is technically the best way to produce the highest voltage step up; only problem with that is that the circuit requires a lone transistor, and that lone transistor has to handle ALL of the load and ALL of the current.

I wish there was some way to make it so there's a true flyback mode driver that uses two switches...