Lansche Audio

I was looking at these Lansche speakers on Keiths website, and they seem really interesting (and probably very expensive!). They use a plasma tweeter which I have only ever seen as crazy DIY projects before. As far as I know they don't have any moving mechanical parts so theoretically are capable of very linear modulation of the air.

Has anybody heard these (Keith obviously!), and more of interest to me are there any measurements of distortion and frequency response from these units? Ribbons are often said to be low distortion but in fact many have very high distortion so I'm curious if these plasma tweeters live up to the theory.



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Simon Hi, I can probably get some measurements from LANSCHE , I know they sound good!
Kind regards Keith.

 

Some good stuff on the history and ideas behind this technology:

http://www.roger-russell.com/ionovac/ionovac.htm

 

Good info there, thanks Rob.

 

At audio frequencies they are horribly non-linear which is why they are modulated. High frequency reproduction above the audible range is probably their main advantage which is largely irrelevant for hi-fi. Set against this is a long list of disadvantages: insufficient SPL, highish cost (relative to a modern tweeter), poisonous output, high voltages, noise,...

I rather doubt those would help the marketing. Here is some background if you read french:

http://kaelig.castor.free.fr/phd.htm

Theory or marketing?

 

What complete tosh HG you really need to do some reading, perhaps you have seen some specs for some DIY efforts, 'poisonous' output wrong again!
You are spouting absolute crap.
Keith.

 

See post #4:
http://www.diyaudio.com/forums/pass-labs/1841-pass-plasma-speaker-history.html

 

Corona Tweeters as used and further developed by LANSCHE do not Icrepeat do not produce Ozone, please do not spread misinformation regarding a product I distribute.
Read about the 'Corona' tweeter before you spread anything libelous,understood?
Keith.

 

The basic operating principle would ordinarily produce ozone but Lansche take steps to address this:

Designer, Rüdiger Lansche -

 

Thanks Rob, I should keep that quote to hand!
The Corona is a superb tweeter, I really cant decide which l prefer the TAD 703 or the Corona, perhaps veering towards the plasma.
Keith.

 

Keith, please try to stay calm. I'm still very interested to see some more detailed measurements of the tweeters performance beyond just frequency response. Many of HG's comments seem true for the older designs but maybe it is not the case here. Also even if distortion is high, that doesn't stop the tweeter sounding brilliant, just like many ribbon tweeters people love the sound.

 

The distortion is high when operated directly at audio frequencies which was in response to your comment about linearity. Like a transistor, these things are not linear but can be operated in a reasonably linear manner by, in this case, modulating a high frequency signal.

If you have a practical inclination these things are fairly easy to design and make so long as you are comfortable with the (potentially lethal) voltages involved. The emissions are not really an issue if your workspace is ventilated. If you can weld there then there should be no problem.

 

Simon Hi I suggest you remove HG posts or I am going to commence libel proceedures against Audio Smile ,I can have some idiot posting his misinformed rubbish on a public forum.

Keith.

 

Recent case law indicates that an adverse opinion is not necessarily libelous if the author can show that he had a reasonable basis of information from which to draw his conclusions.

I reckon you would lose Keith. I don't think h.g.'s posts are libelous. They are his opinion based on information he has studied.

IRRC the case was about a journalist who wrote supposedly critical and disparaging things about the R.S. of Chiropracters.

The R.S.C won in the High Court, but lost on appeal.

JC

 

I'm sure you want to retract that comment after you sober up, Keith.

 

Isn't one of the LANSCHE designers a friend of yours, do you believe he would enjoy those comments from someone who is misinformed and clearly has an agenda.
Keith.

 

Well it didn't take long for this to dive into bickering!

I've no idea who H.G. is....nor have I any interest. Similar applies to Purite.

One thing I will say is that one of these is a business and as such, to 'Joe Public' is seen as a professional. Sadly the behaviour and tone of language implies otherwise.

As ever some folks would do well to remember their place and as always manners cost nothing.

 

Totally unjustified reaction Keith, even if you didn't like the comment prompting it; HG's point is historically quite accurate for this general class of device if not this particular example.

Anyway - picking up the point Tenson made - even if plasma tweeters might not measure that well in conventional terms (I suspect most have a fair-to-ungodly amount of 2nd harmonic at the every least inherent in the way they work)...I'd also bet the cumulative-decay spectrum is unwordly-good; there's no effective moving mass!

 

'totally unjustified' do you manufacture Felix,perhaps you represent a product or provide a service?
I am afraid I take libel ,slander defamation extremely seriously.

 

Keith,

I have edited post 12 to remove a reference to this specific tweeter.

The rest remains as it relates to wholly generic discussion around plasma drivers.

On a more general note, I don't take at all kindly to the type of public threat made in this thread and in future I'd suggest you take up the matter privately first if you have a concern.

No forum will entertain a manufacturer or distributor who resorts immediately to threats of legal action - it simply isn't worth the hassle (or risk) of hosting such discussion. That also goes for all associated products.