Hi Maty
From where did you get the schematic? More to the point, do you know it works? It looks to me like the output from the MOSFETS is fed back positively to the input, independent of Rsen which doesn't feel right.
To me , it looks like topology type 1 from this post 442:
http://www.diyaudio.com/forums/pass-labs/275921-first-watt-f7-review-45.html#post4585617
Fab
quebecdiy.net
Off topic
Fab, I admire your assemblies (and Pinocchio too): quebecdiy.net Transistors
Off topic
Fab, I admire your assemblies (and Pinocchio too): quebecdiy.net Transistors
To me , it looks like topology type 1 from this post 442:
http://www.diyaudio.com/forums/pass-labs/275921-first-watt-f7-review-45.html#post4585617
Fab
Stupid me, it does indeed look like this topology. Still doesn't feel intuitively like it would work but I clearly need to go and try it.
Ian
Stupid me, it does indeed look like this topology. Still doesn't feel intuitively like it would work but I clearly need to go and try it.
Ian
Before building anything you better read this whole thread.
Before building anything you better read this whole thread.
Thanks for the warning although I already read most of the thread. I now recognise that the type 1 topology is more a theoretical one than a practical proposition in that it is way too sensitive to resistor values. Type 2 looks to be a better bet.
From topologies shown in post 442, which would be
best for minimum damping factor variation upon real load speaker impedance
that varies with frequency?
As a concept they all work, that's the central point. The imperfections are
mostly the qualities of the gain stage itself. The best in this regard is the one
with the highest amount of negative feedback and/or the topology with the
lowest intrinsic (open loop) output impedance.
Of course if you already have a very low output impedance, the need for
positive current feedback is very small.
As a concept they all work, that's the central point. The imperfections are
mostly the qualities of the gain stage itself. The best in this regard is the one
with the highest amount of negative feedback and/or the topology with the
lowest intrinsic (open loop) output impedance.
Of course if you already have a very low output impedance, the need for
positive current feedback is very small.
From the above it looks like the open loop gain needs to be higher to have good results with positive feedback....but I thought that lower open loop gain due to use of Lateral mosfet was the reason to use positive feedback...
Fab
From the above it looks like the open loop gain needs to be higher to have good results with positive feedback....but I thought that lower open loop gain due to use of Lateral mosfet was the reason to use positive feedback...
The lower amount of negative feedback on this topology puts in a situation
where the output impedance is not very low. Positive feedback lowers the
output impedance.
If you already have a low output impedance, then you have less need of
this technique.
Yeah the writing style and odd metaphors and expressions often makes it difficult to read. I enjoy the overall approach and thoroughness though - and I love the mountain view out his big glass doors!now they're really worsening the writing style
Hi Srajan,
Thanks for this "never ending" review of the F7. Never before I read such a broad review where one amp was so thouroughfully compared with so many speakers and some other amps.
Your comments about possible reasons that the F7 or 30.8 sounds better with the one or other speaker are very interesting and uncommon in its broadness.
It is of course also a bit hard to see how insecure the perfect matching of an Amp with a speaker is in reality. Compared with the normal reviews, your review is irritating and revealing at the same time.
Thank you!
And continue please.... ))
Thanks for this "never ending" review of the F7. Never before I read such a broad review where one amp was so thouroughfully compared with so many speakers and some other amps.
Your comments about possible reasons that the F7 or 30.8 sounds better with the one or other speaker are very interesting and uncommon in its broadness.
It is of course also a bit hard to see how insecure the perfect matching of an Amp with a speaker is in reality. Compared with the normal reviews, your review is irritating and revealing at the same time.
Thank you!
And continue please.... ))
There are a couple you can try...Reynolds Art Deco and Gradl font....i'm beting it's the second ...but they are very similar.
Both are free fonts....
Just remember the Logo is Nelson's.... respect that.
There are plenty of gorgeous free fonts about....design your own logo.....it's fun.
Both are free fonts....
Just remember the Logo is Nelson's.... respect that.
There are plenty of gorgeous free fonts about....design your own logo.....it's fun.
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