little forensic work
well - just came to my mind - regarding recent dilemma about Papa's revealing of F6 schm
so - Papa is preparing article , and he told us that iin very first post
we aren't just Greedy ........ we are not so rarely even Hysteric Boys
well - just came to my mind - regarding recent dilemma about Papa's revealing of F6 schm
so - Papa is preparing article , and he told us that iin very first post
we aren't just Greedy ........ we are not so rarely even Hysteric Boys
besides fun ....... wittyness , elegance , teasing , spite .........
I can do this 'till tomorrow
Here is a bias generator ZM was talking about. Currently using it on my other amp. Gives nice slow ramp up of bias voltage. I used 1000uF caps instead of 47uF.
I have been thinking about a headphone-amp just to test the circuit. I dont have any other depletion mode fets than DN2540 and SK170-BL. Non of them powerfull enough for driving a 8 ohm loudspeaker without lots and lots of them paralell.
If i had som SiC-J-fets this is what i would build. I like this amp a lot. The simplicity and the use of transformers are brilliant. Its a really smart way to get maximum sonic benefits without the drawbacks. Transformers usually gives a very nice sound. Warm, effortless and organic.
Mvh Johannes.
A) gives us the required phase splitting without any active devices
B) allows easy operation of the top half as a common source
C) simplifies biasing
To achieve the above without a tx would take quite a few active devices IMO - take a look at Digital Do-mains implementation of the same op topology - even the simplified schematic is scary 😉
Forgot the generator link. Post #4
http://www.diyaudio.com/forums/pass-labs/195430-ro85-zen.html
Another point about the SiC parts. I have had multiple recomendations about trying to minimize the use of source resistors.
http://www.diyaudio.com/forums/pass-labs/195430-ro85-zen.html
Another point about the SiC parts. I have had multiple recomendations about trying to minimize the use of source resistors.
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That won't work for this.
Since you already have dual rail voltage (+/-) and you want the negative voltage for the lower (negative) SIT, I think you need a more negative supply attached to the negative rail if this makes any sense.
So a small 6 to 10 volt trans rectified and smoothed, Attach the bias positive rail to the negative rail of the main supply and you should have -10 volts or so more to adjust bias from.
Rush
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There are a number of tube guys, who have been using transformers for phase splitting for awhile now, have discovered that they work better than almost any other phase splitter known to man. Of course, some disagree.
But really good one's aren't always inexpensive, especially when designed as 'inter-stage'. But if you use a phase splitter as the input transformer where signal levels are lower then it gets slightly easier (less expensive). And it seems to me that the F6 uses the phase splitter as essentially, an input transformer. It just happens to be buffered first (probably a requirement for the series feedback arrangement to isolate the feedback loop from the source impedance???).
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Thanks Rush. Wasnt exactly thinking it through, was I? Got your package. Yours should arrive soon. Thanks again.
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Joined 2009
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I mean there are many people who feel that they sound better to their ears. What I like might not be what you like.
hardly that that's the main reason
you ned low impdance to drive two so-called 150R windings in parallel , and are you using buffer or preamp to muscle it , it's irrelevant
in this case , logic is that not all ppl are Susumi Sakuma , having preamps with output impedance in sub 100
Not sure I follow you ZM.
You mean if your transformer has a second winding you are not using to power the output devises? Then yes, that is the same as another transformer.
Or do you mean you can cap couple a rectifier off of one winding and add it to the negative rail? Hum, a digram would help me, not sure about the ground in that case.
Rush
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Buzz posted link to thread where is Pa's schmtc ;
I'll use either additional winding or additional small xformer , but it will work that way
I'll use either additional winding or additional small xformer , but it will work that way
Ah Hah! I am going to go dual secondary route, though.
Edit: the F5 article shows dual bridge configuration.
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