Here is my Model A in action, showing the amplifier and the real time bias meter on the side. I am playing my vinyl copy of Thomas Dolby's classic LP Golden Age of Wireless.
More about the Model A here - http://www.frantone.com/designwritings/design_writings.html #model-a
I originally began the Model A project in late 1999 in preparation for the 2000 New York Noise HiFi builders show. It is an original all tube design, with tube rectifiers, regulators, indicators, and amplifiers in a dual parallel configuration and single toroid power transformer. It has twin 300B triode fixed bias finals and a tube bias supply with dual 6SN7 drivers in a classic configuration. Output is 7 watts per cannel. The dual 6HU6 CRT peak level indicators are out in front which are powered by their own tube regulated 210VDC supply. The chassis and all physical components are entirely hand made from raw stock aluminum by myself. I built the amp over a three month period on my kitchen table in Greenpoint, Brooklyn. I even hand made the single stereo attenuator using a dual gang 48 position continuous coin silver rotary make-before-break switch with 96 wire-wound precision resistors in a logarithmic curve. All of the power supply components are in the top of the chassis and all of the audio components are in the bottom. The two output transformers are set one in each side pedestal and there is forced air cooling throughout. The 'Model A' also runs through a set of high efficiency crossover MTM style speakers that I constructed later in the fall of 2000. It sounds like the voice of God, if there was a God and they had a voice. It is also very, very heavy.
I never entered it in the show, but that is a different story.
More about the Model A here - http://www.frantone.com/designwritings/design_writings.html #model-a
I originally began the Model A project in late 1999 in preparation for the 2000 New York Noise HiFi builders show. It is an original all tube design, with tube rectifiers, regulators, indicators, and amplifiers in a dual parallel configuration and single toroid power transformer. It has twin 300B triode fixed bias finals and a tube bias supply with dual 6SN7 drivers in a classic configuration. Output is 7 watts per cannel. The dual 6HU6 CRT peak level indicators are out in front which are powered by their own tube regulated 210VDC supply. The chassis and all physical components are entirely hand made from raw stock aluminum by myself. I built the amp over a three month period on my kitchen table in Greenpoint, Brooklyn. I even hand made the single stereo attenuator using a dual gang 48 position continuous coin silver rotary make-before-break switch with 96 wire-wound precision resistors in a logarithmic curve. All of the power supply components are in the top of the chassis and all of the audio components are in the bottom. The two output transformers are set one in each side pedestal and there is forced air cooling throughout. The 'Model A' also runs through a set of high efficiency crossover MTM style speakers that I constructed later in the fall of 2000. It sounds like the voice of God, if there was a God and they had a voice. It is also very, very heavy.
I never entered it in the show, but that is a different story.
I recognized that tune but couldn't place it. Funky looking amp, I like it.
Lovely amp, and still going! I'm kinda envious of these 300B as these are expensive tubes. I like the EM84's though. Pity that the video quality is so bad, but hey – it's been over 9 years since the upload. And if I remember correctly from reading the Fransworld archives, the amp was built in early 2000s (ha, I wasn't even doing anything tube-related yet, started in 2004) with an intent of being displayed at an audio builders' show, which didn't happen after all.
cool
Fran, this amp looks amazing! Hope you some day make a new video that explores this amp in more detail! All the DIY tube audiophiles would love it. 🙂 You and your work are awesome – looking forward to all your future videos.
Wow just stumbled across this. What a beautiful amp!
I would love to see a new video of your HiFi audio amp with as much description as you think would be worthwhile.
That must sound amazingly clear in person. I'm listening on my cell and it sounds pretty damn good!
Good test with sir THOMAS
love to see the circuit
i have been looking through your videos and this is the only one i have clicked on so far but its a music video nothing to do with the build of your class A amp i grew up on valves built my first amplifier with valves built my first transmitter with valves would have like to see a valve build project , meanwhile i will go back and look at some more of your selection
I'm still interested in learning more about this one — why you built it and what you wanted to get out of it.
I know this is an old post, but do you still have this? what is the cost of building one? Thanks
Nice..
Love tubes….you may be interested in a power amp I have in the design/prototype stage, a 12vdc powered 200+ watts RMS into 4 ohms using no capacitors and no high voltage converters, no split rails, etc…straight 12vdc, push pull bipolar…yes it can be done…not your conventional amp design, a mix of old school ideas with modern components and recycling! (most of components are from a microwave!)
and it will have some sound characteristics of a tube amp….