F6 Amplifier

[tiefbassuebertr]

Originally Posted by tiefbassuebertr

What disadvantages are to be expected by the use of a single ended input driver stages instead the here showed push-pull jFET version?

the only disadvantage that comes to me in mind is the more difficult design for the driving transformer cause present dc voltage bias.
But what about a small signal circlotron push pull input stage?

[generg]

The combination of the Semisouth I heard in BBA-1 and Aleph-J and and interstage transformer like in Magma ( F4+transformer, similar to M2)
could combine the best of two worlds and really be a dream......!

[tiefbassuebertr]

Originally Posted by generg

The combination of the Semisouth I heard in BBA-1 and Aleph-J and and interstage transformer like in Magma ( F4+transformer, similar to M2)
could combine the best of two worlds and really be a dream......!

I don't know the martked devices. Google provides no helpful results in combination with "Firstwatt"

BTW - concerning interstage resp. driver transformer I have found this old paper:
http://www.freepatentsonline.com/3142807.pdf
and
http://www.sanshinechina.com/eng/sho...p?id=351&pid=8
http://www.geofex.com/article_folder...mp/voxprot.htm
http://www.scribd.com/doc/50982632/0...ull-amplifiers
(design of audio transformers)

Is
http://www.sowter.co.uk/#
a good choice for this kind of transformers?

[Vix]

Well, I must confess that I like transformers...and this amp is a step closer to a Magnetic amp...
I bet that ZM had to console himself by a stone BBQ...
Me..naah...moving amps and speakers..fighting for their (my) place...

[generg]

Originally Posted by tiefbassuebertr

I don't know the martked devices. Google provides no helpful results in combination with "Firstwatt"

BTW - concerning interstage resp. driver transformer I have found this old paper:
Biasing means for transistorized amplifiers
and
Sanshine (Xiamen) Electronics Co.,Ltd
Thomas Vox Solid State Amps
0.5, ... 4 push-pull amplifiers
(design of audio transformers)

Is
SOWTER AUDIO TRANSFORMERS
a good choice for this kind of transformers?

Hallo tiefbass,

kleine Fehler....small errors, of course I meant Burning Amp-1, sprich BA-1, I was confused by BBA-3!

and the Magma was a nice try to combine F4 and an autoformer, to have a M2 like combination without feedback......

Introducing the MAGMA front end for BA-2 and F4

audio rob used a Jensen Transformer JT-13K7-A and published some data...

Gerd

[Melon Head]

Holy cow.

[Melon Head]

Originally Posted by generg

The combination of the Semisouth I heard in BBA-1 and Aleph-J and and interstage transformer like in Magma ( F4+transformer, similar to M2)
could combine the best of two worlds and really be a dream......!

Hey generg.
Have you listened to the BA1, actually more importantly have you listened to the Balanced BA1 in isolation to the front end, using semisouth on output?
That is my next plan, along with this F6, and Balanced BA3.

I now no longer need gain, so my gut keeps telling me to go with balanced single ended source follower (ie power buffer) or source follower circlotron.

I am falling behind now. There are so many ideas to try.
I love this F6 schematic.

[Antoinel]

Originally Posted by Antoinel

Mr. Pass. Thank you for replying. The secondary windings [phase circles] as shown confused me. When the upper winding has a rising positive signal, the upper FET turns on. Simultaneously the lower FET has a matching negative signal to turn it off. Is this an approach similar to OTL [output transformerless] from the past; with identical polarity semiconductors. Then, audiophiles grumbled about an output transformer[phase abberations]; so the interstage one was kept as a compromise [and also absent complemetary devices] because it is inherently higher fidelity. I may have past articles from Radio and Popular Electronics on OTL topology.

Found an article on OTL. Please find attached in this thread and continued in the following one.

[Antoinel]

Page 2 of OTLAmp1 from the above thread is continued in this attachment.

[Zen Mod]

that's boiled water - xformer working as phase splitting device

no use of choking the thread with examples