I don't know, but maybe it's just me... that actually looks quite good and clean (with the output transformers off the side). You might have hit on a different design Wavebourn; instead of outboard power section, you have the outboard output section.
In fact, if you would be so kind as to ship it to me, I would definitely use it as is just so it would be a constant distraction to my wife (maybe shouldn't notice the other projects I have on the go then).
I said that to my wife and she said, "No, I have a cutting board for bread already (she graduated in CompSci with EE, but went all programming for a career, so her reply is quite tongue in cheek)".
Hmmmm... Spectrum analyzer... I might be able use that to figure out when she is upset at me and when she isn't. Signal generator, probably not as she can get pretty monotone. And the white noise generator? Yeah, no comment (I am lucky my wife doesn't read these forums).
Out of curiosity and for a beginner's point of view trying to understand what I am looking at -- since this is running SE pentode, would you ever have the option of running it in Ultralinear? Would you be able to do that? Or is the tube type not good for that?
Ultralinear is a misleading name. It was just a fashion. If you want your tube to be more linear, apply feedback to the control grid. There is a charm in pentode output with high output resistance, speaker distortions are lower for the expense of a frequency response, and vice verse. Also, only early designed pentodes can be used in straight ultralinear mode (and their direct successors); newer pentodes with denser screen grids would need separate windings on the transformer that are already hard to optimize, without some odd copper layers.
Hint: bass response of pentode amps can be tamed by a combination of a negative feedback by voltage and a positive feedback by current.
PS: cheers to your wife!
Hint: bass response of pentode amps can be tamed by a combination of a negative feedback by voltage and a positive feedback by current.
PS: cheers to your wife!
Nice! So a 0C3 for screen reg., and a 12AT7 for gain? Could we have a look at the schem. please.
jeff
First Approximations
Since the G2 voltage is given on any set of pentode curves a very good first approximation can be made of the triode zero bias curve. That originates at the origin & projects to the point where plate & screen volts are equal. See attached.
Then draw in something adjacent that looks like the 3/2s power law if we like.
Power dissipation & load lines can be drawn in for a rather good estimate of power out & so on.
Always worked for me. Might be useful to some here. But a set real curves would certainly be superior.
Since the G2 voltage is given on any set of pentode curves a very good first approximation can be made of the triode zero bias curve. That originates at the origin & projects to the point where plate & screen volts are equal. See attached.
Then draw in something adjacent that looks like the 3/2s power law if we like.
Power dissipation & load lines can be drawn in for a rather good estimate of power out & so on.
Always worked for me. Might be useful to some here. But a set real curves would certainly be superior.
Attachments
6JB6 is the same tube type as 6/12GT5, except for the base. (also same as 6GJ5, 6GW6 and 6JT6, except basing again)
And all of those are fairly similar to, but not exact, to 6JN6, 6/12GE5, 6JM6, 6FW5, 6DQ6B.
I think there are some curves round-abouts online for 6/12GT5, since I have some on the shelf here. If nothing shows up, I can run some curves for the 12GT5.
Crazy Drive:
http://www.diyaudio.com/forums/tube...nificent-television-tubes-52.html#post4583634
And all of those are fairly similar to, but not exact, to 6JN6, 6/12GE5, 6JM6, 6FW5, 6DQ6B.
I think there are some curves round-abouts online for 6/12GT5, since I have some on the shelf here. If nothing shows up, I can run some curves for the 12GT5.
Crazy Drive:
http://www.diyaudio.com/forums/tube...nificent-television-tubes-52.html#post4583634
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When I ride the heater voltage on my spud amps, I observed the increase of sound warmth quality details and loudness.
I know It might be judged by some but I guess when we go to our limits our limits expand.
I fell the tubes sound expands and beside I mostly do it on TV tubes so no one feels sad when they stop functioning properly,
but tubes like that have some interesting uses. I mostly do it on ecc85 ecc81 pl84 and pcf802 triode section,
the pentodes oscillation is something I don't what to dig my hands in.
Too much trouble as my Barber said to my friend I am a Barber not a magician.
I know It might be judged by some but I guess when we go to our limits our limits expand.
I fell the tubes sound expands and beside I mostly do it on TV tubes so no one feels sad when they stop functioning properly,
but tubes like that have some interesting uses. I mostly do it on ecc85 ecc81 pl84 and pcf802 triode section,
the pentodes oscillation is something I don't what to dig my hands in.
Too much trouble as my Barber said to my friend I am a Barber not a magician.
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6MJ6s I don't have. The RCA JEDEC datasheet for them says they are an ultra-reliable field replacement for 6LQ6 and 6JE6. (and 6ME6) Should be curves around for those. It also has almost identical specs to the 21/6LG6 (GE's version). Curves are around for that. 21LG6 and 6JE6/6LQ6 look identical on the curve tracer. A $4 replacement for 6LQ6.
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