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Resolving cold midrange in 5687 circuit

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It does have a lot of gain. Its just a pre-amp.

Interesting circuit. You have a 6N30 driving a 6N6. How's it sound?

I kind of want to go as far as possible with this circuit before dumping it. Just like increasing my knowledge of what each tube/circuit is capable of ...
 
I completely agree.

I'll build it and listen. You've optimized it completely, yes? Very interesting.

This is my first 5687 circuit. Hope I can make it musical otherwise I'm going to try a couple different ones and I'll give yours a go. Thanks.

Have you tried lowering the grid stopper value? Or using a small hand wound air core coil there?

You have capacitor out. I want to stay with trans out. I like the bandwidth. Think they'll be problems dropping a OT in place of the .47?
 
phrarod said:
I completely agree.

I'll build it and listen. You've optimized it completely, yes? Very interesting.

This is my first 5687 circuit. Hope I can make it musical otherwise I'm going to try a couple different ones and I'll give yours a go. Thanks.

Have you tried lowering the grid stopper value? Or using a small hand wound air core coil there?

The circuit is optimized by Dick. The gridstopper / input capacitance allows for somewhat sloppy wiring, the most of us are guilty off. The whole story can be found here. It's a rather large download...

Looking at the circuit I think it's not handy to put an interstage transformer below the cathode. But if you wish, it's possible when you keep it at the right potential.
 
No, mine is in a wooden box.

If you want C-core output transformers I have two 5K:400 ohm units for sale. If memory serves right they're rated 50mA each. Transport will be expensive though (>3KG).

It's a rather big firm and audio has low priority. The waiting list at the moment is 12 weeks...
 
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