trying horns :)

Steve, Im not sure. I know they are ok with single ended amps though.

Always welcome to visit mate.

 

Hi Ian(Data),

here we go.

Guy Sargeant used to work for Audio Innovations. He designed a number of the amps. Things like the P2 phono stage, later versions of the Triode series, later versions of the series 800 & 1000 amps. Also the solid state Alto amp. He is a fan of valve amps & horn speakers. He used some Lowthers and a custom built amp. This love of horns lead to the development of the Living Voice Air Partners.

Kevin Scott runs Definitive Audio. To start off, his company stocked a limit range based around Audio Innovations amps, Snell loudspeakers & the Voyd turntable. Other gear included Helius arms, Audionote cartridges & cables, Goldring cartridges & JPW loudspeakers. This was done from a terrace house in Nottingham. As a dealer, most of the items he sold were supplied by the 'Audio by Design' distribution, an offshot of Audio Innovations. Kevin grew up using valve equipment so when he started his company he went down this path. He too dabbled with horns and heard their strengths. He soon offered horn speakers by Horning & Impulse. From here he decided to see if they could make a even better horn speaker. Doing some research, he came a accross Vitavox catalogue. From this he aquired a Viitavox PA system from a dealer. This system used to be in the canteen at a Vauxhall plant. He & Guy played around with these & found great promise. So from this they got in touch with Vitavox & developed the Air partners.

Kevin Scott ran the project with Guy Sargeant designing the crossovers & the Vitavox doing the work on the bass horn. The resultant speaker cause an stir within the hifi industry. The thing with these speakers, was that the sensitivity was very high. A low powered amp could be used. But the amp needs to quiet & noise free. A number of valve amps were too noisy, so Guy sargeant designed one using a PX4 valve. This amp was the first Border Patrol amp.


Guy Adams owned Voyd designs. As a student, he worked on a pre runner of the Voyd. This was a turntable that Les Wolstenholme had developed using two motors. Guy went away & developed the idea to use 3 motors and an acrylic platter. From this he developed, a range of Voyds ioncluding the Valdi which used two motors. Guy was a friend of Kevin Scott & from this, Kevin got to help out at hifi shows & dems. Peter Qvortrup got to the deck with the Audio Innovations gear & liked the it. So a sort of partnership was formed. Guy Adams has done some other design work. He did a cd player called DAC (Digital Analogue Company) which had a valve output stage & valve rectifcation. I'm not sure but he may have done some work for Audionote.

He sold the rights for the Voyd to Audionote in the 90s and the last I heard, he designed the power supply for the Avid Acutus. I did hear somewhere that he had gone back into industry, non hifi.

Erik Anderson was an early designer for Audio Innovations, designing the first range of amps. He started the company along with Peter Qvortrup. David Chessell became a technical director in 1986. David & Erik then left to form Audion in 1987.

Gary Dews is the owner of Border Patrol. He used to run Definitive Audio in Brighton. His company was a sister company to Kevin's, so he had dealing with Audio Innovations and Peter Qvortrup. He started to produce the Border Patrol amp in 1993. The early version were one offs but model did develop into a full production item in 1997. The later versions had the out board power supplies.

Guy Sargeant continued to work with Audio Innovations until the take over by Audio Partnership (Richer sounds). He then worked at JPW, which was part of the Partnership. JPW are not made any more so I don't know what he is up to.

I have known Kevin & Guy Sargeant for some time. Guy designed some prototype triodes that I purchased off Peter Quortrup. Last time I saw him was a the hifi show in London 1999 or 2000.

SCIDB

 

Fascinating stuff, SCIDB

It's a small, old world innit?

 

Incestious possibly?

 

Dean, how many HiFi Encyclopedias have you swallowed?

But seriously, you constantly amaze me. Keep it up.

 

I recall seeing a foto of a very interesting amp that was to become the audio innovations 3rd audio, with a 211 valve.
BTW, for the uninitiated, its like an 845, but held to be a better valve.And the ongaku uses it. whilst a 2a3 triode gives about 4 watts, a 300b about 8, 211s can give around 20. I am currently running 8 watts into 87db speakers, and it goes plenty loud, so imagine what a good deal more.

These big triodes tho' need about 1000volts, so expensive transformers, and caps., I have had about 5 x 240 volt shocks, so far, and don't wish to go any higher at all.

There are even bigger valves that dwarf even 845s, perhaps running 3000 volts, and are used in the wonderful world of radio transmission and all that, of which I know sweet fanny adams., fascinating tho', a bit like old steam engines. a real pleasure.

check this out, the one on the right is a BIG valve, an 845, just imagine the monstrous on on the lhs, scroll down halfway.


http://www.welbornelabs.com/stuff.htm

Believe it or not, you can get an 845 amp of ebay, for aout £600 saves about £4000 for one of the emporiums, I very nearly plumped for one, but decided I had enough on my plate

Its a shame that 3rd audio never got off the ground and A.I. went the way of the dodo. Really great company. different.

Thanks for that hugely comprehensive potted history BTW. Very informative

Most of these big horns are 100db or more, to put that in perspective, you can use a 4 watt amp say with 103 db speakers, and it will be louder with 1 watt, than a 30 watter max out into 87 db speakers .
There is a school of thought that believes these really low power say 4 watt triodes are the best of all, and combined with big horns, there is nothing to touch them.no not even a naim 500 into dbl's

 

I used to work for a company that made radio-frequency induction heating equipment used for the welding of tube and pipe.

We made oscillators that used English Electric and Brown Boveri valves, capable of outputs of 200kW. They were ceramic, rather than glass, but weren't all that big considering. The output transformers were about 5 feet high, 4 feet deep and 3 feet wide. The mains transformers were similarly frightening.

I imagine you could make a fairly decent hi-fi amp with such valves, provided your speakers were sufficiently efficient.

 

Hi ian,

I too remember seeing the 3rd Audio amp by Audio Innovations. This was at a hifi show. AI had planned to make a range that went up to the 6th Audio amps.

They are plenty. Here are some.

Whether a valve amp is good or bad depends more than just the type of output valve. The 845 need higher voltages to work at higher power outputs. This in term needs better quality transformers, power supplies and other components that can handle these high voltages. Also the 845 is harder to drive than say a 300B. I have heard a few 845 amps in my time and a number can sound glorious in the mid range but lacking & limp at the extremes. Some, like Steve M has said, can sound lacking full stop. But if you get it right, it can sound great. You can build one quite cheaply, whether it is any good depends on a number of factors. The 845 at high output are not a project for the faint hearted due to the high voltages.


It is a shame that the 3rd Audio amp (& others) never got off the ground. It was a big shame AI went down the pan. This was the company that got me really interested into valve amps.

SCIDB

 

funny you mentioned the 'alto' amp dean. This was the amp in the demo that first got me interested in hifi about 12 years ago.

The system consisted of epos ES11, Audio Innovations Alto and Rotel 965BX.

The guy who introduced it to me (at Lintone audio metrocentre) was a valve nut, and showed me the other AI products of the time, they did (and do) look glorious I think.

I couldnt afford any more than a 400 quid system at the time, but I dreamed!! Second hand audio innovations valve amps can be a great purchase. I know that you used to have some Dean - cant remember the model though?

The alto is a great little amp, and a fun shape. It would show a clean pair of heels to many a richer sounds specials I think, and I bet they are available for very little cash these days.

I'll dig out a picture..

I prefered it in black, heres a chrome one

 

Well, for those vaguely interested in my horn escipades, Ive had a change of heart.. to some extent.

After a lot of pondering, Ive decided to skip the hardline horn idea, and go for a great big massive horn, coupled to a bass cab, probably with a 15" bass driver. I may use a tweeter for very high frequencies too. Slot tweeters seem to be popular for this, although Im not sure why horn users pick these? (nb like in the picture below, the slot tweeter is below the horn)

Im borrowing a horn and a bass cab to make sure I like the idea, and if I do, its all systems go to make one, using a cabinet maker and some people far more knowledgeable than I to put it together.

Of course, if I dont like the bass cab/horn mid-treble combination with the demo model, it will be a non starter. I dont think thats likely but we wil see.

Here is a picture of one that is very similar to what I will end up with:

 

Jeez, they sure are pretty, with a high WAF factor for sure

 

hahah yeah. instant boxes of divorce!

If I get them now though, thats pre-wife and pre-bird so to speak, so she will be used to them when she turns up!!



p.s. I kind of like them in a no-compromise made for purpose industrial kind of way.

Mine would have oak cabinets, and I'd want the horns sprayed black.

 

Cool. Nuts, but cool.

-- Ian

 

in-f*ckin-sane. let me know if you still need halp shifting things about.
cheers


julian

 

thanks !

anyone know anything about slot tweeters?

Ive had no experience of them yet, and wondered why they are popular with horn users to get high treble?

 

bottleneck,

I'm trying to find a way to get divorced without loosing half of my house, half of my Hifi and half of my other stuff.

You just gave me an idea!

 

Bottleneck - It's a trade-off between the matching the high efficiency of the midrange and getting enough dispersion so that the speaker sounds balanced over the listening area.

The tweeters are usually horn-loaded compression drivers - there's no 1" diaphragm on earth that could handle enough energy 'naked'. Even if there was, it would beam / not integrate well with that midrange / not last very long! The horn orientation gives dispersion to suit the (very large) vertical dimension of the rest of the speaker.

 

thanks felix!

Ive tried to ask more questions on the (unofficial) vitavox forum, but for some reason I cant get my computer to be able to use the forum I dont know why.

You dont use horns yourself do you?

Cheers
Chris

 

Some time ago I visited a forum (something to do with horns but can't remember which one) and asked what the main games were around horn design. They told me that it was about engineering the dispersion characteristics of the drivers.

Other than having fun with dispersion I think that it's all about trading colouration, size, bass extension and efficiency. I've always found it amusing that when horn designers compliment each other's speakers they describe them as 'not sounding like horns'.

Nevertheless, there's something about the highly efficient way that a horn speaker matches a room that has a sense of 'rightness' to it. Not for me though. My game is designing to a size. I don't do large.

 

Chris when you get your horns you might like to get these for those personal moments or when yer on the bus.

http://www.audiocubes.com/product_info.php?products_id=1005&osCsid=a06803a2a104d5f6fe6695686e1c20d7