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 NEW  Matt presents bias and operation data for the 6V6 tube in SE operation - 6V6 Single-Ended (SE) Ultra Linear (UL) Bias Optimization.

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It is currently 17 Jul 2019, 10:46

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PostPosted: 01 Feb 2017, 12:33 
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Joined: 01 Jun 2013, 09:05
Posts: 716
I thought I would post this for interest.

The circuit is from another forum a Rockola juke box.
I think it has some interesting anomalies:
Phase splitter
Nobel networks
Speaker field coils.
Take a look at the volume a guess its loudness compensation.

M. Gregg

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What is the sound of one hand clapping?

PostPosted: 01 May 2017, 14:47 

Joined: 29 Apr 2017, 15:14
Posts: 43
that seem to me, not a vol control, but a bass boost, it will boost the bass
mid way on its run, as the position of the capacitor is shown, on the wiper
of the pot. treble is cut by flipping of the spdt switch wired on to the anode
of tube type 76, note how phase splittin is obtained by the autotransformer
effect, unlike wat we do now, with a tube, just remarkable!!!

PostPosted: 02 May 2017, 18:10 
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Joined: 04 Jun 2008, 20:59
Posts: 3987
Location: Arizona, USA
Hi, At least they used good output tubes. I am surprised they didn't use a typical interstage trannie instead of the autotrannie. They could get a bit more gain. The volume control is odd.

Good listening

Some of my DIY Tube Amplifier Projects:

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