Hi folks,
This schematic is from one channel of my Cary pre amp.
Would it be possible to not use both outputs from the two 12AU7s in parallel but insead use each of the second outputs to duplicate the basic circuit for a differential application?
Since I am not familiar with tube amps I probably fail to see the necessity of the paralleled tube output.
This schematic is from one channel of my Cary pre amp.
Would it be possible to not use both outputs from the two 12AU7s in parallel but insead use each of the second outputs to duplicate the basic circuit for a differential application?
Since I am not familiar with tube amps I probably fail to see the necessity of the paralleled tube output.
I think the best way is the use of a signal trafo at the output
The circuit has a low Zout so isn’t difficult to find a good one with a s.e.to balance output
The circuit has a low Zout so isn’t difficult to find a good one with a s.e.to balance output
The tube halves are in parallel for better drive capability. For differential outputs you’ll need a different circuit. With output capacitors in each leg.
Is it balanced or differential you are after? I think balanced.
It is way simpler to construct a beefier circuit driving an unbalanced to balanced transformer. Just 1 coupling cap.
Of course things are even simpler driving that transformer with semiconductors and large value but low voltage capacitors. Or no cap at all so DC coupled. Just a semiconductor circuit driving that transformer.
Or a semiconductor unbalanced to balanced conversion circuit without transformer.
https://thatcorp.com/that-1606-1646-balanced-line-driver-ics/
Less is more.
Is it balanced or differential you are after? I think balanced.
It is way simpler to construct a beefier circuit driving an unbalanced to balanced transformer. Just 1 coupling cap.
Of course things are even simpler driving that transformer with semiconductors and large value but low voltage capacitors. Or no cap at all so DC coupled. Just a semiconductor circuit driving that transformer.
Or a semiconductor unbalanced to balanced conversion circuit without transformer.
https://thatcorp.com/that-1606-1646-balanced-line-driver-ics/
Less is more.
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You don't need parallel tubes in that circuit. You could reconfigure the inut stage as a long tailed pair, each having its own cathode follower buffer output, creating a decent SE to balanced preamp.
Sorry I didn't spot the error.
I wanted to convert the circuit to balanced in and balanced out using one half of the tubes for the positive and the other for the negative signal.
I wanted to convert the circuit to balanced in and balanced out using one half of the tubes for the positive and the other for the negative signal.
Then the thread title does not cover what you want. The question is if you need gain or not, what the drive capability of the source is and what it will drive itself. See it as a black box with a certain function. What is the function?
Just imagine you could get away with using/adding nothing 🙂 That likely is not what you want to hear.
Just imagine you could get away with using/adding nothing 🙂 That likely is not what you want to hear.
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