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Stereo Buffer with a single twin triode

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I'm looking to build a stereo buffer amp but possibly with just 1 twin triode such as a 6N6P.

I heard that crosstalk is not really an issue so I would like to see if I can use 1 triode to handle the left and right signals.
Input source will be a standard CDP and the buffer will be used with a SS power amp.

CDP>Buffer>Power amp.

Simple self bias cathode follower is on my mind here. But how to design this with the left and right signals is puzzling me a little. Please take a look and let me know.
 

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You can eliminate the caps. on the I/P side, if you use a bipolar PSU.

Constant current sink (CCS) loading is an excellent idea. While a SS cascode or pentode is "best", even the comparatively simple 10M45S will be better than a resistive load.

I agree with SY, in that your schematic makes sense. What is it about stereo that's got you worried?
 
Wow, that circuit is mouth watering...TWO caps in the signal path...for a buffer preamp that's rarely needed nowadays...you had me at "Hello"

Had a feeling that leadbelly would chime in first. Lol
Yes I wasn't sure about the caps.

What software did you open this with?




IMHO if you going to build this at least put a CCS in place of the cathode resistor

I need to look into this as I'm not too familiar with CCS. Any references to circuit ideas would be great.

I agree with SY, in that your schematic makes sense. What is it about stereo that's got you worried?

Most of the designs seem to use 2 separate tubes, one for each channel. If there is no crosstalk involved I'd like to use the 2 triodes in one tube.
Do I need a twin triode with a screen to implement this design? The article that leadbelly included states there are 2 types of 6N6P.
 
well my first order was on the 10th Jan and nothing yet.

I just wrote to them and they replied in 10 mins saying they will ship the item again with a free item up to a value of 10USD. Sounds too good to be true.

I have 45 days to open a dispute with paypal. I will wait a little longer and open a dispute before the 45 days just in case.
 
Brit01 said:
Most of the designs seem to use 2 separate tubes, one for each channel. If there is no crosstalk involved I'd like to use the 2 triodes in one tube.
Do I need a twin triode with a screen to implement this design? The article that leadbelly included states there are 2 types of 6N6P.

Crosstalk (or the lack thereof) is overrated. Anyone who listens to vinyl is limited by the separation of the cartridge, which is 30dB tops, usually less. It would be a rare tube which does not have better separation than that. You will also see many amps with a single input or driver tube, comprising a dual triode, with or without (usually without) a screen. Whatever crosstalk is there won't be audible under stereo listening.

Sheldon
 
Brit01 said:
What software did you open this with?
Do I need a twin triode with a screen to implement this design?

.mdi just stands for "microsoft digital imaging" or something like that. It opened on mine without installing anything, but I have all the MS Office addons installed.

Don't worry about the screen. There are already some threads debating this if you want to search.

Brit01 said:
But I'm trying to keep the circuit as simple as possible without sacrificing performance too much.
This is getting a little too complicated.

The guys here normally eschew 3pin regulator based CCSs because they are lower performance than discretes. IMHO, you might be happy with a circuit that has an LM317 or 10M45 for a CCS. Pretty simple, 1 unit with 1 or 2 resistors.
 
IMHO, you might be happy with a circuit that has an LM317 or 10M45 for a CCS. Pretty simple, 1 unit with 1 or 2 resistors.


Not sure if this is the way to go. I checked out several articles and took this from glass-ware and incorporated into my circuit.

R3 and C2 I'm not sure about.
 

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I have my doubts about using a regulator IC. OTOH, the 10M45S has achieved considerable popularity among DIYers. More than 1 set of ears indicate the use of the application specific IC.

Let's see if the circuitry can be simplified. A 10M45s and its associated passive parts for the cathode load. A stack of red LEDs directly under the cathode for bias. The CCS sits between the LEDs and ground. Make R4 50 KOhms. R3 sits between the grid stopper and the LED stack/CCS junction. Make R3 511 KOhms.
 
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