Let me toss out the idea of gain another way. For an otherwise all solid state vinyl playing rig. What value of mu would be ideal for the, Ultimate Aikido, input tube; 100 for a 12AX7, 70 for a 6SL7, 20 for a 6SN7, other?
That solid state power amplifier will most likely go into hard clipping with 2 volts input.
DT
All just for fun!
That solid state power amplifier will most likely go into hard clipping with 2 volts input.
DT
All just for fun!
Agreed! We have officially made the transition from
"SS rectification vs. Valve rectification"
to
"CLC filtering vs. Voltage Regulators"
Regulators are wholly a different issue than Rectifiers! I couldn't agree more. A regulator (solid-state or valve) easily offers voltage headroom to mitigate signal-induced current variations. (However, an open-loop capacitance multiplier, even when equipped with a Zener for regulation and voltage headroom, still has high impedance).
Thanks! You've correctly pointed out the missing datapoints until real solutions can be offered.
What is the OP's signal chain?
What are the components?
How much signal drive does he need?
What other components in the signal chain are contributing gain?
What's the input impedance of the next component after the Aikido?
Is he already listening to his system with the volume knoB at the 9:00 position?
Kashmire,
The Akido output cathode follower will remain on my list of toys to play with. Yes the balance of 180 degree out of phase current with the input pair will be lost. Noise cancellation will be retained (I think). There is the capacitor and voltage divider that injects any B+ AC disturbance at the grid of the lower triode of the output cathode follower. That is the same feed forward noise reduction used in a power supply. It works in BeigeBag. It looks worth trying in the real world.
DT
All just for fun!
The Akido output cathode follower will remain on my list of toys to play with. Yes the balance of 180 degree out of phase current with the input pair will be lost. Noise cancellation will be retained (I think). There is the capacitor and voltage divider that injects any B+ AC disturbance at the grid of the lower triode of the output cathode follower. That is the same feed forward noise reduction used in a power supply. It works in BeigeBag. It looks worth trying in the real world.
DT
All just for fun!
My signal chain is thus:
Turntable: Yamaha GT 2000
Cartridge: Soundsmith 'The Voice'(Ebony)
Phono Stage: Simaudio Moon LP 5.3
Preamp: Transcendent Sound Grounded Grid
Active Crossover: Accuphase F-25
Treble Poweramp: Kenwood L-06M monoblocks
Bass Poweramp: Kenwood L-06M monoblocks
Speakers: diy activated 846A Altec Valencias
I have found the Accuphase F-25 sounds better with less gain applied via it's controls(not oveloading the inputs of the poweramps?).Thus the Grounded Grid is typically used with it's volume control at '3 o'clock'.
Having listened to a few expensive systems over the last few years containing such equipment as (Ayre CD player,ASL preamp,Krell CAST poweramp,JM Lab Alto Utopia Be) and (Electrocompaniet CD player,preamp,Electrocompaniet Nemo monoblocks and B&W 802D speakers),I can say that my system might lack bandwidth extension via both bass and treble to both those systems,but the resolution and musicality is superior.
I would not swap my system for either of those,unless I could sell them and buy my present one again plus pocket the not insubstantial difference in dollars ;-).If I had to live with any of the three(mine or the other two),I'd stick with what I've got.
It's amazing what can be achieved with less money and a two good ears.
I'm quite happy for people to discuss the merits/demerits of different approaches to every aspect of the Aikido,as long as their own conclusions are based upon choices that they have made and implemented which have shown an improvement which increases resolution(ie no information lost).
I am not interested in 'improvements' (let's say to the depth and imaging) which lose information in the bass or indeed anywhere across the bandwidth.These are the sorts of 'soothing sounds' which I stated in my initial post that I am not interested in.The staging and imaging I am looking for are those which were captured on the software by the venue/miking arrangements etc.
I don't want a preamp which interprets.I want a preamp which resolves or loses as little information as the design allows.
Design choices which move me closer to that ideal(it's called 'High Fidelity'..) deliver the greatest connection with the music,I have found.I can't appreciate a bigger soundstage if I've just lost insight into what the performers are doing below 150 Hz.
The Aikido would drive the Active Crossover: Accuphase F-25, which should be an easy load. However, the F-25 is rated at signal of 2.0V.
I'm afraid an Aikido would add too much gain to the Simaudio Moon LP 5.3 Phono Stage, and overdrive the F-25's input, unless you attenuate a lot of your signal to knock it back down.
Before we discount the Aikido totally, calculate total system gain.
The Soundsmith 'The Voice'(Ebony) is moving-magnet, correct? This means the LP 5.3 is adding 40dB of gain.
I'll get back to this later this evening, and calculate how much gain you'll actually need to feed the Accuphase.
I'm afraid an Aikido would add too much gain to the Simaudio Moon LP 5.3 Phono Stage, and overdrive the F-25's input, unless you attenuate a lot of your signal to knock it back down.
Before we discount the Aikido totally, calculate total system gain.
The Soundsmith 'The Voice'(Ebony) is moving-magnet, correct? This means the LP 5.3 is adding 40dB of gain.
I'll get back to this later this evening, and calculate how much gain you'll actually need to feed the Accuphase.
Another option to use the Aikido magic is to use the Aikido Phono Preamp Kit. Item# Ph-1 Kit followed by a stepped attenuator to replace the existing phono stage and GG.
I am now using the TubeCad Ph-1 to drive a 6BQ6GTB SET headphone amplifier with pleasant results. The phono stage directly drives the SET output tube, no line stage or driver tube is needed.
DT
All just for fun.
I am now using the TubeCad Ph-1 to drive a 6BQ6GTB SET headphone amplifier with pleasant results. The phono stage directly drives the SET output tube, no line stage or driver tube is needed.
DT
All just for fun.
I have done the following aikido flavors:
1. 12au7 input 12au7 output
2. 6n1p input 12au7 output
3. 12sl7 input, 12sn7 output
4. 7n7 input, 12sn7 output
5. 12sn7 input, 12sn7 output
6. 6cg7 input, 5687 output
7. 6cg7 input, 7119 output
Of all the above, I like the 6cg7 input the best with the 7119 output, next will be the 6n1p input 12au7 output.
Am using a Denon turntable with Denon 103R cartridge, a Lundahl SUT with aikido phonostage (12at7 input 12au7 output), 2a3 SE and Vandersteen 1C.
1. 12au7 input 12au7 output
2. 6n1p input 12au7 output
3. 12sl7 input, 12sn7 output
4. 7n7 input, 12sn7 output
5. 12sn7 input, 12sn7 output
6. 6cg7 input, 5687 output
7. 6cg7 input, 7119 output
Of all the above, I like the 6cg7 input the best with the 7119 output, next will be the 6n1p input 12au7 output.
Am using a Denon turntable with Denon 103R cartridge, a Lundahl SUT with aikido phonostage (12at7 input 12au7 output), 2a3 SE and Vandersteen 1C.
Have you tried it with the Aikido?
I am ordering some LDR and kit, and I am planning to use it on my Aikido.
Did you optimize the operating conditions (current, voltage, cancellation resistors) for each of those tubes? Just randomly plugging stuff in and out is unlikely to get you anything close to best performance. It's worthwhile using a variable supply and a spectrum analyzer to get each tube combo working at its best- you can easily see 6-10dB difference in distortion with the same tube, not to mention distribution of harmonics.
The Soundsmith output will be approximately 1mV to 2mV. It is rated at 0.6mV/cm/sec. At a velocity of 5cm/sec, the output maximum is 2.12mV.
The Simaudio Moon LP 5.3 has a gain of 40dB, which is voltage gain of 100. This means the signal output of the Simaudio will be approximately 100-200mV.
The Transcendent has a gain of 12dB, which is voltage gain of 4. The final signal output will be approximately 400-800mV.
The Accuphase is rated for 2.0V, so you are with reasonable limits of the Accuphase's input.
The final question to determine the acoustic output is your power amp gain and the efficiency of the speakers, but we'll ignore that for now.
Your system seems very nicely gain-balanced.
Let's analyze if we can keep your good gain situation by replacing a component with an Aikido.
Consideration 1: replace the Transcendent with an Aikido with 12dB gain (voltage gain of 4). Look at the Aikido web page to see various valves and gains. Some good options are:
Consideration 2: replace both the Simaudio and the Transcendent with a high-gain Aikido phono amp with attenuator. You'll need 52dB of gain to replace both components (40dB + 12dB = 52dB), which is a voltage gain of 400. This is too much gain for a single stage, so you'll need a multi-stage device.
Consideration 3: Build two Aikidos, one high-gain phono Aikido to replace the Simaudio (use 12AX7 voltage gain of 40) and a second to replace the Transcendent (use 6SN7 or 6CG7 for voltage gain of 10). The total gain will be 400, the same as your existing system. You'll have to perform RIAA equalization and be careful with protecting the delicate input signals to the photo stage.
You have plenty of room for optimization. I'd suggest starting with idea #1, replace the Transcendent and keep the Simaudio. You have a good selection of valves. Your best bet may be 4 x 12B4 per channel, capitalizing on some of the previous posts in this thread of using four individual valves instead of two dual triodes.
Please double-check my math, I'd appreciate corrections/feedback.
The Simaudio Moon LP 5.3 has a gain of 40dB, which is voltage gain of 100. This means the signal output of the Simaudio will be approximately 100-200mV.
The Transcendent has a gain of 12dB, which is voltage gain of 4. The final signal output will be approximately 400-800mV.
The Accuphase is rated for 2.0V, so you are with reasonable limits of the Accuphase's input.
The final question to determine the acoustic output is your power amp gain and the efficiency of the speakers, but we'll ignore that for now.
Your system seems very nicely gain-balanced.
Let's analyze if we can keep your good gain situation by replacing a component with an Aikido.
Consideration 1: replace the Transcendent with an Aikido with 12dB gain (voltage gain of 4). Look at the Aikido web page to see various valves and gains. Some good options are:
12B4 (voltage gain of 3.4), single triode
6BX7 (voltage gain of 4.5), but a power tube
12BH7 (voltage gain of 8)
6GC7/6SN7 (voltage gain of 10)
6H30 (voltage gain of 8)
12AU7 (voltage gain of 8)
6BX7 (voltage gain of 4.5), but a power tube
12BH7 (voltage gain of 8)
6GC7/6SN7 (voltage gain of 10)
6H30 (voltage gain of 8)
12AU7 (voltage gain of 8)
Consideration 2: replace both the Simaudio and the Transcendent with a high-gain Aikido phono amp with attenuator. You'll need 52dB of gain to replace both components (40dB + 12dB = 52dB), which is a voltage gain of 400. This is too much gain for a single stage, so you'll need a multi-stage device.
Consideration 3: Build two Aikidos, one high-gain phono Aikido to replace the Simaudio (use 12AX7 voltage gain of 40) and a second to replace the Transcendent (use 6SN7 or 6CG7 for voltage gain of 10). The total gain will be 400, the same as your existing system. You'll have to perform RIAA equalization and be careful with protecting the delicate input signals to the photo stage.
You have plenty of room for optimization. I'd suggest starting with idea #1, replace the Transcendent and keep the Simaudio. You have a good selection of valves. Your best bet may be 4 x 12B4 per channel, capitalizing on some of the previous posts in this thread of using four individual valves instead of two dual triodes.
Please double-check my math, I'd appreciate corrections/feedback.
It's funny,I posted on another site with a thread titled "What next after Transcendent Sound Grounded Grid?"
I only got a couple of replies.One of them suggested:
12B4 line stage
----------------
Search following words on google.
"yet another 12b4 line stage 12b4 better than grounded grid"
The Google search lead to this page:
http://www.diyaudio.com/forums/tube...ine-stage-12b4-better-than-grounded-grid.html
Bah Humbug. I wrote a nice reply, and it disappeared when I hit "Preview Post". So I'll re-write the good parts.
From Mark's post:
Some circuits are fussier than others. The Aikido greatly decreases a tube's individual sonic contribution while maximizing linearity. This comes at the cost of higher complexity, because the Aikido requires 4 valves.
For Mark's single-valve 12B4 linestage,
The Aikido offers a much larger PSNR (Power Supply Noise Rejection), again, at the cost of requiring 4 valves.
It seems your "Magnum Opus Aikido" (is it OK to mix Latin and Japanese?) would be 12B4. It matches your system well. Of course, you want all the tricks. Use dual-mono construction, separate enclosures for the power supplies, film power supply capacitors, power supply voltage regulation, PIO coupling capacitors, DC filaments, etc. I'd toss in valve power supply rectification, too.
From Mark's post:
Some circuits are fussier than others. The Aikido greatly decreases a tube's individual sonic contribution while maximizing linearity. This comes at the cost of higher complexity, because the Aikido requires 4 valves.
For Mark's single-valve 12B4 linestage,
The Aikido offers a much larger PSNR (Power Supply Noise Rejection), again, at the cost of requiring 4 valves.
It seems your "Magnum Opus Aikido" (is it OK to mix Latin and Japanese?) would be 12B4. It matches your system well. Of course, you want all the tricks. Use dual-mono construction, separate enclosures for the power supplies, film power supply capacitors, power supply voltage regulation, PIO coupling capacitors, DC filaments, etc. I'd toss in valve power supply rectification, too.
I hate it when the 'net loses a f*cking fine internet post.
That sound pretty good.Any specific resistor type?
I like Holco. I'm sure there's some debate about different resistors, but I tend to subscribe to the Nelson Pass theory. (1) pay attention to circuit topology to minimize component's individual colorations while maximizing sonic contributions, (2) pay attention to smartly choosing active devices and their bias currents, and finally (3) the passive parts.
For capacitors, there are plenty of threads of "which one is best"? Pick a good one and try it. You can always swap alternatives to see if you can hear any differences. For your ultimate project, your starting point should be at the top level: Mundorf PIO, Jupiter, or Jensen PIO.
The goal, however, is to have a linear system that contributes as little sonic coloration as possible. Exotic capacitors may impart their own coloration, which may be highly desirable for some people, but not necessarily you.
For capacitors, there are plenty of threads of "which one is best"? Pick a good one and try it. You can always swap alternatives to see if you can hear any differences. For your ultimate project, your starting point should be at the top level: Mundorf PIO, Jupiter, or Jensen PIO.
The goal, however, is to have a linear system that contributes as little sonic coloration as possible. Exotic capacitors may impart their own coloration, which may be highly desirable for some people, but not necessarily you.
FWIW, Broskie sent me what he thought were optimum parts for the Aikido- Russian Teflon caps and Vishay bulk metal foil resistors. Not naked ones, these had the normal encapsulation. It all worked fine, but I'm unconvinced about the actual improvement over more prosaic parts- the version I built with Wima FKP and Panasonic metal film resistors sounded identical.