Any new design sliding bias amps out there ?

[Jakobsson]

Any design with large BJT´s are interesting.
I am an old Denon fan and likes the sliding bias but looking for something new.
Using an old PMA-1560 which i like very much.

Pelle

[Steve Dunlap]

You might check out my Krill amp. It is a little controversial at the moment.

[Jakobsson]

Interesting design ,i have to go through the schematics and the comments to be able to say anything about it.
My first thought is that i like the simplicity in it but it looks like it has to be very carefully balanced when it comes to selecting parts for it.

Pelle

[kenpeter]

Allison is another sliding bias worth considering:
If you don't mind the low low input impedance.
Directly into a pair of emitters! Input Z actually
not as bad as it might seem, because its also a
follower of the input.

Though I tend to abuse a pair of Alephs as-if
they were an Allison. Same thing only different.
Into the emitter, rather than the normal way...
Voltage followers rather than current sources.

----------------------------------------------

With Allison, any curvature of the output devices
is hidden inside the sliding bias correction loop(s).
Same - Same the forklift of Alephs as I use.

Its not hard to get shut-off-less AB with a cold
pair of Schottky diodes strung between error
corrected sliding bias followers of any topology.
Far easier than to match cutoff curves of hot
"complimentary" N and P transistors.

------------------------------------------

All these amps could be considered variants
of the diamond buffer.

[tiefbassuebertr]

check out this thread:
Denon's MOS "Super optical Class A" from PMA1560 - how works this circuit

[Bigun]

can you post the design Denon uses for Sliding bias ?

[Piersma]

hi,

You must defenitely check out Edmond Stuart's great website on this subject: data-odyssey.nl

regards,
Piersma

[tiefbassuebertr]

Originally Posted by Bigun

can you post the design Denon uses for Sliding bias ?

Does the attachement about the mentioned URL not go open?

At my opinion this is - in opposite to the output voltage dependend sliding bias about
http://www.freepatentsonline.com/3995228.pdf
an input voltage dependend sliding bias about opto coupler. I don't understand the theory of operation exactly, but it is clearly not an auto bias design respective a self biased design, because there are two bias potentiometers for adjusting;
1) one for the basic value (arround 20mA/each power bjt) and
2) one for the sliding bias threshold

about
Dynamic Bias - Active Bias - Automatic/Self biased - Overview wanted
you will find an overview about more variations

Originally Posted by Piersma

hi,
You must defenitely check out Edmond Stuart's great website on this subject: data-odyssey.nl
regards, Piersma

Thank you for this advice about auto bias design's