Rare drivers... talk about luck

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steve s
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#1 Rare drivers... talk about luck

Post by steve s »

My red obs use quite a rare fane driver, I've been on the lookout for a matching pair for my next speaker.
They are vintage fane drivers but with a high spec 20,000 line magnet.

Most vintage fanes come with magnets in the 10 to 17,000 range but i need the bigger magnet so they mate with the beyma tpl150s with very similar efficiency and sound

A few months ago I picked up a single 12" and a 15" (both 8ohm) with the 20,000 line magnets.
Looking at the readily available vintage fanes I have, the baskets and mountings look identical in all types
There are only two types of cone, the hifi/ pa low resonance surround and the pop cone for guitar work

Anyway, the other night I removed the large magnet from the 15" and fitted it to a 12" pa cone/ basket. I was not expecting to be easy but it turned out to be so easy. It took about 10 mins
I then connected it up to the sig gen and gave it a blast.
The pa cone gave 15 db more volume at 30 hz and was louder to 150 hz than the pop cone.
Measuring the speaker about 6" in front of the cone, it was realitivly flat out to 6khz. (I'm only going up to 1500hz with them though )
Quite something.. much better than all of the modern drivers I've been looking at.
Playing music it sounded better than the pop cone.. very very fast.. and a good match for the beyma
That was enough for me to convert the other one, which was just as easy

So I now have a great pair of 15 ohm speakers for my next project. And also few spare baskets/cones and the ability to replace them.. which is a good thing
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
Cressy Snr
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#2 Re: Rare drivers... talk about luck

Post by Cressy Snr »

Sounds like an excellent turn up for the books there Steve.

I used to lust after Fane Pop 100s, Baker Majors and EMI 13"x 8" ellipticals "with twin tweeters and crossover" during the early 70s, looking at the ads in Practical Electronics, for the RSC shop in Doncaster Waterdale Centre.

I was a strange kid.

Ex TV ellipticals from Dolly Morgan's junk shop in Swinton, were all I could afford on my pocket money. :lol: :lol:
Sgt. Baker started talkin’ with a Bullhorn in his hand.
steve s
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#3 Re: Rare drivers... talk about luck

Post by steve s »

You lusted after quite a selection of speakers steve, I turned my nose up at a 12" bakers driver last weekend
I have two pairs of the larger magnet emi's I always thought they would stack and make good OB bass drivers... one pair are ex decca decola, they where used in some expensive speakers in the day
Cheers
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
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IslandPink
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#4 Re: Rare drivers... talk about luck

Post by IslandPink »

Good effort ! Must be a fair bit of standardisation on the voice coil diameters and other parts then ? - makes sense I suppose.
I suppose 'lines' is the old term for 'Gauss' then, is it ?
"Once you find out ... the Circumstances ; then you can go out"
steve s
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#5 Re: Rare drivers... talk about luck

Post by steve s »

IslandPink wrote: Sat Nov 18, 2017 12:14 pm Good effort ! Must be a fair bit of standardisation on the voice coil diameters and other parts then ? - makes sense I suppose.
I suppose 'lines' is the old term for 'Gauss' then, is it ?
It surprised me how they are all the same dimensions Mark, and the voice coils where as far I could see the same.. lucky for me. I'm not sure what the total gauss is Mark but it's a lot
The magnet is in lowther territory but on a much bigger pole
Expensive speakers in their day and now daft prices for used.
The voice
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
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IslandPink
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#6 Re: Rare drivers... talk about luck

Post by IslandPink »

After a bit of searching & reading I'm pretty sure a Gauss is a 'line'
https://www.translatorscafe.com/unit-co ... 2%b2-line/
Just a bit confused about cm^2 and m^2 options - I suspect both are referred to cm^2 in this application.
Gauss is the CGS unit and Tesla is the SI unit.
I Tesla = 10,000 Gauss if you use cm^2 . Certainly in loudspeaker gaps this is the conversion, Lowthers are in the range 1.8T to 2.4T :
http://www.lowtherloudspeakers.com/a-series.html
"Once you find out ... the Circumstances ; then you can go out"
steve s
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#7 Re: Rare drivers... talk about luck

Post by steve s »

IslandPink wrote: Sat Nov 18, 2017 1:18 pm After a bit of searching & reading I'm pretty sure a Gauss is a 'line'
https://www.translatorscafe.com/unit-co ... 2%b2-line/
Just a bit confused about cm^2 and m^2 options - I suspect both are referred to cm^2 in this application.
Gauss is the CGS unit and Tesla is the SI unit.
I Tesla = 10,000 Gauss if you use cm^2 . Certainly in loudspeaker gaps this is the conversion, Lowthers are in the range 1.8T to 2.4T :
http://www.lowtherloudspeakers.com/a-series.html
Thats my understanding too Mark so mine are 2t
There is a total gauss too stated for many vintage drivers, the vitavoxs if I remember correctly where 275,000
These fanes are on par with efficiency but much better sounding higher up..
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
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