Vitavox 6 cell horns
 

Hi

I bought these in an auction, did a quick test feeding them from the house valve hifi, Beard P100 MkII.

They produce a very accurate sound, in a proper set up they must be quite special.

Not much info on the web about them, appear to be 220 series, with GP1 drivers.
One is a 220E, with original throat to GP1 driver.
One is a 220S, with adaptor throat to GP1 driver.

The Mrs has already said they can not stay in the living room ....., something about ugly :-)

Richard

Re: Vitavox 6 cell horns
 

Glastonbury might be an appropriate setting for them? What a lovely pair!

Re: Vitavox 6 cell horns
 

I've always wondered about these big Vitavox horns, were they originally PA horns that people now use for hifi?

Re: Vitavox 6 cell horns
 

When I was involved in acoustics, I used to teach and work a little on horn systems. I remember there seemed to be a consensus that subdividing a horn attached to one driver didn't do very much , the normal maths analysis assuming that no velocity components (pressure gradients) occur across the horn cross-section, rendering the 'web' invisible. FE analysis would reveal things here, I guess.

I wonder how true that was. I guess mechanically the web is useful in stiffening up the whole structure.

Where in frequency do you think the cut-on is for these ones? It's a simple function of flare constant, as I remember.

Re: Vitavox 6 cell horns
 

I used to use Vitavox horns and GP1s and 2s in my PA hire business in the 70s and 80s. I believe these horns have a flare cut off frequency around 300 Hz.

I always considered the Vitavox equipment to be beautiful pieces of mechanical engineering. The multi cell arrangement was supposed, I believe, to overcome the 'focussing' of the sound into a narrow beam at high frequencies. I cannot speak personally how effective this was but quite a few reputable American manufacturers also produced multi cell horns.

Re: Vitavox 6 cell horns
 

I remember seeing similar used in cinemas large lecture-theatres/halls and theatres.

Re: Vitavox 6 cell horns
 

Vitavox did sell full range units comprising a multi cell horn and woofer in a cabinet with crossover.

One of the founder's (Len Young) sons runs Secomak Ltd. and I seem to remember buying some replaceement GP1 diphragms off them but this was some years ago now.

I think someone set up a company to service the old Vitavox audio equipment using the Vitavox name. They did have an internet presence but I don't know if they are still around.

Bob

Re: Vitavox 6 cell horns
 

Hi all

Mark - with my lash up in the living room, if with just one channel on I walked across the room, about 8ft (far nearer than I expect they were designed for) in front of the horn there were 3 distinct zones. Crossing further away these had disappeared.

I found some information: -
http://website.lineone.net/~empson/220.html

These were hand made, and available up to 15 cells!
Cut of is 220Hz

They are not practical for my living room, and I can not justify putting them in the workshop (Chapel), although I expect it is the sort of space they were designed for, so I expect I will sell them, problem is at the moment I have no idea what they are worth lol.

Richard

PS - as per forum rules, I welcome ideas as to value, but please no offers in direct forum.

Re: Vitavox 6 cell horns
 

Ah, you've reminded me of the other iffy assumption in the classical maths (Webster horn equation?) - that the waves remain in contact with the horn walls. Yes, I guess the diaphragm directivity takes over at high frequency - in fact that's what phase plugs are all about, now I come to think of it.

Funny how quick you can forget things :)

Re: Vitavox 6 cell horns
 

Beauty is in the eye of the beholder, but to be fair alot of these lived behind cinema screens. When's your's due? ;D

Re: Vitavox 6 cell horns
 

One solution to that is to put them up for auction. They would then hopefully reach a price which reflects their value - or at least whatever someone is willing to pay for them.

Re: Vitavox 6 cell horns
 

Many years ago, I had one of these together with the huge Vitavox crossover and one of their 15 inch bass drivers in a reflex cab. Despite an audibly lumpy response, it sounded uncannily lifelike at times, and was extremely efficient.

Re: Vitavox 6 cell horns
 

One with GP1 driver sold for £365 (with 9 bids) on Ebay in January.

Re: Vitavox 6 cell horns
 

Interesting that horn theory turns out to be very complex. My simple interpretation is that a basic horn, like a PA 'trumpet', emits a strong plane wave component at mid-frequencies, unlike the more spherical radiation of a cone speaker. That accounts for the long range that such speakers provide (perhaps mostly heard today with ice cream chimes :) ).

That plane wave of course makes the single horn awkwardly directional, particularly at high frequencies. The practical answer is to use a bunch of horns, each pointing in a different direction. The multicellular horn is just that, and it's long application in cinemas is testimony to the uniformity of its polar diagram. I believe that a mathematical analysis is tricky, and it's interesting that today's PA horns use various wondrous shapes, including the well-known 'cheeks' rather than a multicellular approach.

Martin

Re: Vitavox 6 cell horns
 

Looking at an american Altec Lansing cinema speaker gives some idea of how they would have been utilised. You might need bigger woofers!

A few months ago, Drew Pritchard bought some on 'Salvage Hunters'

Re: Vitavox 6 cell horns
 

The comment about Glastonbury would be closer. They have rows and rows of horns set in arches high on the stage in an attempt to push the sound out to the crowds. Sound quality is still terrible though due to the effects of wind, reflections and phase cancellation problems.