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What AMP did KEF used ?

 
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qguy
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PostPosted: Wed Mar 15, 2006 6:47 am    Post subject: What AMP did KEF used ? Reply with quote

What amplifier did KEF used to developed their loudspeakers in the 70's
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ColinR
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PostPosted: Thu Mar 16, 2006 11:06 am    Post subject: Reply with quote

Quad power amplifiers were used by both KEF and B&W to voice their loudspeakers from the 60's to the 90's and can be found inside their active designs.
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qguy
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PostPosted: Thu Mar 16, 2006 10:41 pm    Post subject: Reply with quote

Quad,

any specific models ?, a Quad 405 has been offered to me for sale, but info from the net says that this is not a good amp
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ColinR
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PostPosted: Thu Mar 16, 2006 11:33 pm    Post subject: Reply with quote

Quote:
Quad 405 not a good amp


Utter rubbish, you couldn't build a Quad 405 for the original price even using components bought trade.

405 amplifier modules can be found in Meridian M100's, 303 and 405's in BBC active Spendors and LS designs and 520 bits in the KEF KM1.

So does internurd opinion have these down as bad speakers? No.

Ok the 405 and 405-2 used TL071 op amps in preference to Burr Browns and it's not rated from DC to 4Mhz, but then again they don't go bang by themselves that often.

If you buy it, get a £70 Quad service and enjoy the warm and cuddly sound it produces.
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Parts
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PostPosted: Fri Mar 17, 2006 11:36 pm    Post subject: Reply with quote

Did they not also use Meridian and maybe Early Musical fidelity (MVX and A370) in the 80's and 90's?

The Meridian 601 pre had a digital Kube processor thingy.

And in Meridians early custom install days they at times used kef and Meridian electronics together ?
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ColinR
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PostPosted: Mon Mar 20, 2006 9:23 pm    Post subject: Reply with quote

Yup Very Happy .
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Stuart Booth
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PostPosted: Tue Mar 21, 2006 8:09 pm    Post subject: Reply with quote

Depends what you want to hear. I'm on my 3rd 405, currently a 405-2, thanks to burglary and my ship failing to come home once upon a time, don't you know.

If you want atmospheric whiz bangs buy a Linn or some esoteric red and black plastic box with gold nobs and a Greek sounding name. If you want to hear realistically balanced music (of any genre) then buy the Quad. I guarantee, once bitten you will always return, no matter what other mystical ether you stray into.

Better yet, combine it with a pair of LS3/5a's or Kef based TL's and you may find yourself opting for early retirement and hiring a maid. (to change the Vinyl that is)

Now there's a thought!
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qguy
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PostPosted: Tue Mar 21, 2006 10:46 pm    Post subject: Reply with quote

Stuart Booth wrote:


If you want to hear realistically balanced music (of any genre) then buy the Quad. I guarantee, once bitten you will always return, no matter what other mystical ether you stray into.


This sounds like good advise

Better yet, combine it with a pair of LS3/5a's or Kef based TL's and you may find yourself opting for early retirement and hiring a maid. (to change the Vinyl that is)


I do have a maid, but I won't retire in the next 30 years or so, otherwise how the heck am I going to pay for the maid ??? Twisted Evil


Now there's a thought!
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speakerguru
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PostPosted: Fri Apr 28, 2006 2:38 pm    Post subject: Reply with quote

ColinR wrote:
Quote:
Quad 405 not a good amp


405 amplifier modules can be found in Meridian M100's, 303 and 405's in BBC active Spendors and LS designs and 520 bits in the KEF KM1.



Sorry I have to correct you again Colin. The KM1 only ever used 405-2 modules. The 500 series boards were used in the K300 amplifier (with the P60 speakers) and also in the much later AVI THX subwoofer.
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ColinR
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PostPosted: Fri Apr 28, 2006 4:38 pm    Post subject: Reply with quote

Quote:
and 520 bits


I was thinking about the power supply(ies) actually, the one I saw looked very 520ish, also because of the KM1's studio credentials I would have expected a "hard" supply to have been used.
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proffski
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PostPosted: Sat Apr 29, 2006 1:00 am    Post subject: Reply with quote

I adore the sound of the current dumpers; the MKI was a bit of a wimp was it not? Produced rated power into resistive loads and hated tricky ones. Certainly hated B&W DM70s!!!
MKII was a much finer beast; remember repairing some a long time ago...

Oh, them were the days.
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speakerguru
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PostPosted: Tue May 02, 2006 11:36 am    Post subject: Reply with quote

ColinR wrote:


I was thinking about the power supply(ies) actually, the one I saw looked very 520ish, also because of the KM1's studio credentials I would have expected a "hard" supply to have been used.


The KM1 used two 405 power supplies to power 8 x 405-2 amps. The 405 mains transformers were the very square C-core potted ones. 500 series amps used a big toroidal transformer.
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ColinR
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PostPosted: Mon May 08, 2006 4:39 pm    Post subject: Reply with quote

Quote:
The KM1 used two 405 power supplies to power 8 x 405-2 amps. The 405 mains transformers were the very square C-core potted ones. 500 series amps used a big toroidal transformer


I'm going to be very polite here Very Happy .


I've called in a favour and can confirm that the pair I saw in bits, had/has a modified power supply for the amplifier blocks following a transformer failure in one.
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