I'm a newbie, and trying to decide which Aikido Line Stage to build. Which topology could give a tonally neutral, but holographic, 3-D soundstage, and extended response?...
I don't know the differences between the topologies of CCDA, SRPP, or Cathode Coupled. I don't need much more than 10 dB gain. I have enough matching sets NOS tubes from RCA, Sylvania, Philips, and Telefunken to go with either octal or 9-pin.
Many Thanks
I don't know the differences between the topologies of CCDA, SRPP, or Cathode Coupled. I don't need much more than 10 dB gain. I have enough matching sets NOS tubes from RCA, Sylvania, Philips, and Telefunken to go with either octal or 9-pin.
Many Thanks
The Aikido is a specific topology. So are CCDA, SRPP and Cathode follower (I assume that is what you meant). So your question 'which Aikido Line Stage' is nonsensical in the context in which it is presented..
All of the circuits could provide the characteristics you describe, depending on on how they are implemented (not so sure about the holographic bit though). Cathode followers in isolation provide again of around 0.9.
All of the circuits could provide the characteristics you describe, depending on on how they are implemented (not so sure about the holographic bit though). Cathode followers in isolation provide again of around 0.9.
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In most systems the best tonally neutral (but I'm not sure about "holographic") line stage is a short piece of wire, possibly connected to a volume pot. Wire has an extended response too, from DC up to many MHz. Your probably need around 0dB gain.
As mach1 has pointed out only the Aikido linestage is using the Aikido principle, the totem pole arrangement of two triode halves
sitting on top of each other (don't shoot me when this is a somewhat crude abbreviation of how it works...).
Built properly it can sound very nice since I built an Aikido headphone (noval) amplifier a few years back.
When you know how to solder and you have a nice stash of tubes to try this should be a rewarding project for a newbie.
I cannot comment on the other linestages, they all might have their merits but I'd stick to the Aikido.
sitting on top of each other (don't shoot me when this is a somewhat crude abbreviation of how it works...).
Built properly it can sound very nice since I built an Aikido headphone (noval) amplifier a few years back.
When you know how to solder and you have a nice stash of tubes to try this should be a rewarding project for a newbie.
I cannot comment on the other linestages, they all might have their merits but I'd stick to the Aikido.
The one he calls the Akido line stage is the one I like. its the one with the triodes stacked (srpp)
Leave it to Booskie to put a twist to the application that has been around for more than 50 years. I had to laugh when he discovered that he couldn't patent it and he just said "There is no new tube circuits, just discoveries of the old and forgotten"
Leave it to Booskie to put a twist to the application that has been around for more than 50 years. I had to laugh when he discovered that he couldn't patent it and he just said "There is no new tube circuits, just discoveries of the old and forgotten"
JB called a hum nulling method "Akido" and has used it in a variety of circuits, not just one type.
See this quote from the Tube CAD Journal, Vol. 3, Number 3.
"Surely, our aim is a quiet amplifier. Achieving that aim is possible from two approaches.
The first is the way of the brute force: large chokes, large filter capacitors, and voltage regulation.
The second is the way of canceling the noise by artful noise injection, balancing, and nulling.
This last approach is not one single topology, but rather a family of techniques and stratagems.
The problem is that this practice lacks a name. As Nietzsche pointed out "As people are usually constituted,
it is the name that first makes a thing generally visible to them." So here is a name: "Audio Aikido."
Like Aikido, force is not met with force, but instead the force is used against itself."
The point I was making is that CCDA, SRPP and Cathode follower are not separate subsets of what is generally promoted commercially by Broskie as the Aikido topology.
correct. akido is his slang for noise nulling or noise compensation circuit. Which started appearing in schematics as early as 1940
Always the confusion between the SRPP and the Half-Mu circuit. There is nothing push-pull about the Aikido or the Half-Mu.
The Half-Mu is the first half of the Aikido, the second half is a Broskie modified cathode follower. If you do not require any gain go ahead with the BCF of Broskie Cathode Follower.
DT
The Half-Mu is the first half of the Aikido, the second half is a Broskie modified cathode follower. If you do not require any gain go ahead with the BCF of Broskie Cathode Follower.
DT
'noise nulling or noise compensation circuit. Which started appearing in schematics as early as 1940'
I think Loftin and White may have had it nailed in 1929 😉
I think Loftin and White may have had it nailed in 1929 😉
I think your right about loftin white, but it seems the technology took some time to get around.
Of course, there was chaotic things going on in that era to explain that (WWI and WWII for example)
Of course, there was chaotic things going on in that era to explain that (WWI and WWII for example)
88 Man, I've built a few
of the headphone Aikidos. They work best with high impedance phones. I built a linestage using four 6CG7s. It sounded a bit too "tubey" so I changed it to 6CG7 gain tube and 6DJ8 output. It sounds much better now. If you go for the Broskie kits the noval (9 pin) Stereo and a PS1 power supply kit would be my choice if your budget permits. The stereo version allows putting the input tube filaments in series and the output tube filaments in series and running the filament supply at 12 volts. This puts less stress (heat) on the filament rectifiers. The full kits with all the parts are a good deal.
If budget is a concern you might try the Aikido 12Vac but build the 12 volt version (6DJ8s) not the 18 volt (12AU7s). The kit with all the parts is a good deal. The output caps in the kit are OK but I'd upgrade to $10 or $20 Mundorfs or any other decent cap right away. The 1uF 1kVdc Cornell Dubilier polypropylene film capacitors offered as an option by Broskie won't fit on the board unfortunately.
See link for a review of the 12Vac.
Battle of the Cheap Line Stages – Part 1 | Wall of Sound | Audio and Music Reviews
Cheers, Steve
of the headphone Aikidos. They work best with high impedance phones. I built a linestage using four 6CG7s. It sounded a bit too "tubey" so I changed it to 6CG7 gain tube and 6DJ8 output. It sounds much better now. If you go for the Broskie kits the noval (9 pin) Stereo and a PS1 power supply kit would be my choice if your budget permits. The stereo version allows putting the input tube filaments in series and the output tube filaments in series and running the filament supply at 12 volts. This puts less stress (heat) on the filament rectifiers. The full kits with all the parts are a good deal.
If budget is a concern you might try the Aikido 12Vac but build the 12 volt version (6DJ8s) not the 18 volt (12AU7s). The kit with all the parts is a good deal. The output caps in the kit are OK but I'd upgrade to $10 or $20 Mundorfs or any other decent cap right away. The 1uF 1kVdc Cornell Dubilier polypropylene film capacitors offered as an option by Broskie won't fit on the board unfortunately.
See link for a review of the 12Vac.
Battle of the Cheap Line Stages – Part 1 | Wall of Sound | Audio and Music Reviews
Cheers, Steve
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