@PKI Oh come on now, you know we dont talk about sound all that much here, and the answer is always going to be “build them and determine it yourself…
That said, with all of these projects, the answer is to build the one that is the most interesting to you, and obviously the one you have parts for.
Also worth mentioning, Nelson has mentioned, many times, that the light bulb amps sound fantastic. They also have the added advantage of the current source (the bulb) not requiring any heatsinking. And your listening room lights up. They are so simple it’s worth a try.
That said, with all of these projects, the answer is to build the one that is the most interesting to you, and obviously the one you have parts for.
Also worth mentioning, Nelson has mentioned, many times, that the light bulb amps sound fantastic. They also have the added advantage of the current source (the bulb) not requiring any heatsinking. And your listening room lights up. They are so simple it’s worth a try.
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When someone made an amplifier in a basebord heater, that will be of my interest !@PKI Oh come on now, you know we dont talk about sound all that much here, and the answer is always going to be “build them and determine it yourself…
That said, with all of these projects, the answer is to build the one that is the most interesting to you, and obviously the one you have parts for.
Also worth mentioning, Nelson has mentioned, many times, that the light bulb amps sound fantastic. They also have the added advantage of the current source (the bulb) not requiring any heatsinking. And your listing room lights up. They are so simple it’s worth a try.
That was mine back in 2010, I couldn’t find bulbs (globe) rated 300W so I had used another 300W rated lamp...they were lightly..dimmed.Also worth mentioning, Nelson has mentioned, many times, that the light bulb amps sound fantastic. They also have the added advantage of the current source (the bulb) not requiring any heatsinking. And your listening room lights up. They are so simple it’s worth a try.
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If you want to go back to the very beginning in 2007 check out:
The Burning Amp Festival- an Audio Happening
It's full of cool pictures and commentary on the first several BAFs. Boy, some of us sure looked a lot younger back then. But Nelson still looks as distinguished and cool as he does now. Don't be discouraged by the dead links to Photobucket and the like. There is still plenty to entertain you for a couple of days. I believe videos didn't start happening until BAF was moved to Redwood City around 2011. Have fun checking it out!
So after re-reading Nelson's article a number of times and trying to figure out the puzzle pieces it seems to me that member Ben Mah has already a ready to go solution for the puzzle piece defined on page 14 first paragraph. His Single Ended Tokin SIT THF-51S Common Drain Mu Follower Amplifier , 45W? thread is a mu follower with a -60v rail, the THF51S's drain tied to ground and the IXNT40P50P's drain tied to the -60v rail. In Nelson's words a MUFF (avoiding PS noise injection into the output - a Greedy Boyz priority).
Please enlighten me if I am barking up the wrong leg of the SIT here.
Please enlighten me if I am barking up the wrong leg of the SIT here.
I have been running my amp for over a year. Sounds Great!
https://www.diyaudio.com/community/...mu-follower-amplifier-45w.371187/post-6649547
I agree about the greatly lower PS noise when using the V- supply (the PFET muff).
However, I have found a major advantage of using an NFET muff with the V+ supply which I will post soon. With a simple cap. multiplier the noise issue can be solved.
Here is an NFET muff where the resistor R1 rthe last schematic of "Burning Amp 2022 – Simple DIY SIT Power Amplifiers" is eliminated and the voltage to the gate of the NFET is generated by an opamp lopass filter with an appropriately long time constant. The NFET muff simplifies the use of an opamp since the inputs are near ground and ground, and the opamp power can +12V and ground.
The gate of the SIT is biased using the voltage across a resistor from the positive rail connected to an adjustable constant current source.
Simulations look excellent, showing THS of around 0.3% at 50W into 8R, negative phase H2. More details to come.
While working on simulations for the various SIT muff alternative topologies, I have become a true believer in the benefits of the SIT muff. The AC currents of the SIT and mu-follow FET have a very linear character, unlike with the SIT/PFET push-pull designs. This linearity means that simple current bias circuits can maintain nearly perfect bias current, even at high signal levels.
The gate of the SIT is biased using the voltage across a resistor from the positive rail connected to an adjustable constant current source.
Simulations look excellent, showing THS of around 0.3% at 50W into 8R, negative phase H2. More details to come.
While working on simulations for the various SIT muff alternative topologies, I have become a true believer in the benefits of the SIT muff. The AC currents of the SIT and mu-follow FET have a very linear character, unlike with the SIT/PFET push-pull designs. This linearity means that simple current bias circuits can maintain nearly perfect bias current, even at high signal levels.
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Why reinvent the wheel? Just for the looks on visitors faces I might build another using these. Vintage Filament ST45 Dimmable Light Bulb
Might need five per channel but that would make it even more fun?
Might need five per channel but that would make it even more fun?