And Hugh to this, I would say….
http://www.diyaudio.com/forums/atta...1-gnfb-inspired-steven-dunlap-krill-schem-gif
Bigun stated that he got it from Hugh in this post:
http://www.diyaudio.com/forums/soli...spired-steven-dunlap-krill-4.html#post5523804
He poured scorn on the Krill, saying it could not work.
I do not know enough engineering to know either way, but I suspect it does work.
You can check the posts back through the years. It makes interesting figures.
HD
I do not know enough engineering to know either way, but I suspect it does work.
You can check the posts back through the years. It makes interesting figures.
HD
Some understatement in this sentence, I would say 😉
That Krill interested me, and I found a thread which is a good read, and not too long....
DIYHiFi.org • View topic - The Steve Dunlap Krill amp
Late Charlie Hansen was quite positive about it there, but what did HE now anyway...apart cranking out some of the absolutely finest amplifiers. He is missed, sorely.
The issue was that there was very little bias on the spreader and it was hard to understand it could generate bias in the non active driver.
There are other regimes to ensue all outputs remain on (viz allison outputs) but in practice there seem little reduction odd order harmonics. Further my later work with the active CCS diamond buffer I took from Andrea Ciuffoli's block showed high levels of odd harmonics at all levels, and since it sounded very good in critical listening tests I came to the conclusion it really was not the goal for best sound.
I admire Hansen and his Ayre models reflected his physics training. A deep thinker. I wish I had stronger math so I could manipulate some of the poor models.
HD
There are other regimes to ensue all outputs remain on (viz allison outputs) but in practice there seem little reduction odd order harmonics. Further my later work with the active CCS diamond buffer I took from Andrea Ciuffoli's block showed high levels of odd harmonics at all levels, and since it sounded very good in critical listening tests I came to the conclusion it really was not the goal for best sound.
I admire Hansen and his Ayre models reflected his physics training. A deep thinker. I wish I had stronger math so I could manipulate some of the poor models.
HD
Don't you think it is strange that the audience preffered good sounding middle thd nngnfb amp?
Do you think it is time to demistify thd as old fashioned main factor for good sq?
If someone needs realy low thd then it should just rise power rails...
Do you think it is time to demistify thd as old fashioned main factor for good sq?
If someone needs realy low thd then it should just rise power rails...
Member
Joined 2009
Paid Member
Steve didn't find it easy dealing with people on the forum and vice versa. It can be a rough place and Steve was in a bad place from a health perspective. He's not been active for a long time. People objected to some of his claims about his amplifier, especially saying it was 'non switching' at the output. This was later clarified by another forum member 'andyc' who sadly left the forum for similar reasons (difficulty interacting with people) but who was very talented. The amplifier is really a Class AB output but there are signals and circumstances where it does not switch (current always flows). REGARDLESS there were many good reports of good sound from his amplifier. I am FULLY persuaded that his amp works (I know of at least one person in private correspondence who built it and said it was good); it is worthy of proper attention in the DIY community. I have adopted it's output stage for my TGM11.
The non-switching mode is a form of cross-conduction. This is a parasitic mode that is usually to be avoided at all costs if you want a reliable amplifier not one that blows up. So, plenty of reasons to be scornful. However, exploiting this mode is what Steve's amp does. I rather like the rebel approach that Steve took and admire his work. I also respect the work from those who were critical such as Edmond who has considerable experience and talent himself. So, I suggest you folk dive in with your soldering irons and find out for yourselves!
The non-switching mode is a form of cross-conduction. This is a parasitic mode that is usually to be avoided at all costs if you want a reliable amplifier not one that blows up. So, plenty of reasons to be scornful. However, exploiting this mode is what Steve's amp does. I rather like the rebel approach that Steve took and admire his work. I also respect the work from those who were critical such as Edmond who has considerable experience and talent himself. So, I suggest you folk dive in with your soldering irons and find out for yourselves!
Last edited:
Hi
It's easy to see how the output stage is biased, beginning with the current sources trying to pull both sides ON as hard as possible and the bias regulator in between taming it down.
The odd part is how the signal is coupled in. It seems a little "loose" to me.
It's easy to see how the output stage is biased, beginning with the current sources trying to pull both sides ON as hard as possible and the bias regulator in between taming it down.
The odd part is how the signal is coupled in. It seems a little "loose" to me.
Member
Joined 2009
Paid Member
There's no loosey-goosey with the signal here as the Diamond buffer is essentially a set of cascaded source followers and the Krill biassing network floats with the signal.
How many people at DIYaudio actually built this Krill amp?
It appears 2009, so in 9 years there should be someone can give us a review.
I always liked it, but I like to design and sell my own ideas, so I would not offer any comment of the SQ.
HD
It appears 2009, so in 9 years there should be someone can give us a review.
I always liked it, but I like to design and sell my own ideas, so I would not offer any comment of the SQ.
HD
Hi,
Just had a thought. What if I did the circuit as I described in my first post but used 3 diodes and at a resistor at the emitter to make it into an AB amplifier and use it in a bridge configuration ( 2amplifiers) with a bipolar cap in between, since it will be impossible to match the bias.Then build a simple one transistor phase splitter to create the out of phase signal. Do you think it would sound good?
Oon
Just had a thought. What if I did the circuit as I described in my first post but used 3 diodes and at a resistor at the emitter to make it into an AB amplifier and use it in a bridge configuration ( 2amplifiers) with a bipolar cap in between, since it will be impossible to match the bias.Then build a simple one transistor phase splitter to create the out of phase signal. Do you think it would sound good?
Oon