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Octal Cornet

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Hi all,

I've finally decided to make the jump to tubes. After a great deal of going back and forth between DIY and bargain used phono stages, not to mention between SS and tubes.... I've decided and ordered parts. So... no turning back now.

I'm building the octal version of the Hagerman Cornet. I should get 38db gain from this and another 30db from a pair of Lundahl 1678's.

My Rotel 970 provides 62 db gain and it's a bit on the low side.

I'll keep ya'll posted on this, my very first foray into DIY tubes.

Bobbi
 
diyAudio Senior Member
Joined 2002
Hi,

I'm building the octal version of the Hagerman Cornet. I should get 38db gain from this and another 30db from a pair of Lundahl 1678's.

68dB of gain...where 30dB of it is derived from a xformer isn't what I would do...

Oh, and adopting the Hagerman circuit to take octals would upset the RIAA equalisation as well...unless he's got an octal version ready, I didn't check yet.

Anyway, we're here to help...

Cheers and glad you want to try out those good ole tubes...;)
 
Octal Schematic

New Octal schematic

So he's already worked out the RIAA issues.

I'm open to suggestions on the transformer. I'm living with 62db now, so I guess I could go as low as 24db gain through the transfomer. I haven't ordered them yet. 24 db would be possible with the one's I was planning to order. 26db would be possible with a different ratio set up.

Specifically, what would be wrong with having that gain through the xfmr. I'm just learning here.

The parts for the Cornet are on order, so that's what I have to work with.

Bobbi
 
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