Hey All!
Is Frank's 6SN7 preamp still in vogue? I bought a lot of 6CG7, 6CG7/6FQ7, and 6FQ7 tubes (yea yea, they're the same, etc... ) and have been looking around at circuits to build.
I'm torn between the Aikido circuit and Franks'... both seem to be excellent!
Help me make up my mind! Please?
Thanks!!
Is Frank's 6SN7 preamp still in vogue? I bought a lot of 6CG7, 6CG7/6FQ7, and 6FQ7 tubes (yea yea, they're the same, etc... ) and have been looking around at circuits to build.
I'm torn between the Aikido circuit and Franks'... both seem to be excellent!
Help me make up my mind! Please?
Thanks!!
Have you listened to both?
We can't be the ones to make up your mind as that is something you will have to do based on Your opinion. Personally I have a few AIkido's and I also have Franks 5692 line stage. I like them all.
I favor the Aikidos because they have less or no noise because of the design.
My Franks line stage I used VR tube regulation for each channel. Making a line stage isn't that expensive. Surely one could muster up the money to make one and six months later make another line stage.
We can't be the ones to make up your mind as that is something you will have to do based on Your opinion. Personally I have a few AIkido's and I also have Franks 5692 line stage. I like them all.
I favor the Aikidos because they have less or no noise because of the design.
My Franks line stage I used VR tube regulation for each channel. Making a line stage isn't that expensive. Surely one could muster up the money to make one and six months later make another line stage.
The Aikido topology interests me in that it canceles out the power supply noise while also amplifying a desired signal, which sounds like it would be a very quite preamp. But I've never worked with VR tubes before, so that might be a fun thing to play with. In my mind, Frank's, with a dual-mono layout, 'feels' like it would be a better sounding preamp due to the robust power supply.
I have heard neither circuit.
I'm a student, and as a result what I can and can't do is limited by the time between classes and the space in my bedroom--I could build both, it may take me a couple years to get each up to snuff, but in the end one would be dismantled and I have serious attachment issues with things that I build.
I'm curious: if the sections of a tube, or tubes across pairs, were not well matched, how well does the Aikido design hold up? (conjecture, worst case scenario)
I was being facetious, however I guess you could say it's akin to how the Marantz 7 was once popular, despite the fact that there were better circuits out there to listen to. My question was one of inquiry into whether I missed a better trick or not.
This was call-out for members who have heard both and who could chime in on the subject (thank you, 6BG6GA!) and voice their opinions. Yes, it does matter on what tubes you use; a Telefunken sound can vary wildly from the signature of an RCA, but it's just a feeler. The 'in vogue' bit was more a of question for information about a better circuit.
Apologies if the wording of this reply feels somewhat awkward, I had a better reply typed up but then the page refreshed itself and my message was gone.
I have heard neither circuit.
I'm a student, and as a result what I can and can't do is limited by the time between classes and the space in my bedroom--I could build both, it may take me a couple years to get each up to snuff, but in the end one would be dismantled and I have serious attachment issues with things that I build.
I'm curious: if the sections of a tube, or tubes across pairs, were not well matched, how well does the Aikido design hold up? (conjecture, worst case scenario)
I was being facetious, however I guess you could say it's akin to how the Marantz 7 was once popular, despite the fact that there were better circuits out there to listen to. My question was one of inquiry into whether I missed a better trick or not.
This was call-out for members who have heard both and who could chime in on the subject (thank you, 6BG6GA!) and voice their opinions. Yes, it does matter on what tubes you use; a Telefunken sound can vary wildly from the signature of an RCA, but it's just a feeler. The 'in vogue' bit was more a of question for information about a better circuit.
Apologies if the wording of this reply feels somewhat awkward, I had a better reply typed up but then the page refreshed itself and my message was gone.
In the years I have practiced with tubes I have made in the neighborhood of a dozen and a half line stages. I have heard probably at least 50 or so others. In my opinion Franks and the Aikido are tops. Yes, I have heard the Marantz also but was never impressed with it. Have played with a number of the Aikido's have 6sn7/6sn7, 6au6/5687, 6fq7/5687 just to name a few. Have done pc boards and point to point. Did Franks 5692 with a primitive power supply and it sounded great. Went several steps up from there and it sounds good. I'm not going to mention any names but both the Aikido and Franks design will blow away line stages costing several thousands of dollars.
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I'm curious: if the sections of a tube, or tubes across pairs, were not well matched, how well does the Aikido design hold up? (conjecture, worst case scenario)
Never bothered to match the sections. In the real world I don't think most will take the time to go thru 50 or so tubes to come up with something close. Haven't had anything that I popped into the socket sound bad yet. Have auditioned some of the most coveted 6SN7's out there. The 5692 which most will say sound the best. The Russian 1578's will blow everything to the curb in my opinion. I've kind of formed the impression that the good circuits do not seem to change sound much when high dollar components are used but then again there are those that will argue the point. The better the power supply the better the sound in my experience with most designs. The Aikido on the other hand does not need something special in the way of the power supply in order to sound good Just my .02
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I'm curious: if the sections of a tube, or tubes across pairs, were not well matched, how well does the Aikido design hold up? (conjecture, worst case scenario)
Never bothered to match the sections. In the real world I don't think most will take the time to go thru 50 or so tubes to come up with something close. Haven't had anything that I popped into the socket sound bad yet. Have auditioned some of the most coveted 6SN7's out there. The 5692 which most will say sound the best. The Russian 1578's will blow everything to the curb in my opinion. I've kind of formed the impression that the good circuits do not seem to change sound much when high dollar components are used but then again there are those that will argue the point. The better the power supply the better the sound in my experience with most designs. The Aikido on the other hand does not need something special in the way of the power supply in order to sound good Just my .02
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So if I wanted to do up an Aikido with Frank's PSU, it would be a wasted effort? What I'm getting at is that if the tube is trying to cancel out noise while amplifying a musical signal, there must be a point where some really, really noise PSU hinders the performance of the preamp!
(by design, the Aikido doesn't want/need a fansy shmancy PSU, but thought I'd ask)
Don't underestimate the value of two cents; thank you for your most-valuable input, 6BG6GA.
*edit* One more question! How would you treat the 1578 tubes when building the Aikido? I have a document that outlines the circuits' resistor and capacitor specs on a per-tube basis... would I build the circuit setup for 6CG7/6CG7?
(by design, the Aikido doesn't want/need a fansy shmancy PSU, but thought I'd ask)
Don't underestimate the value of two cents; thank you for your most-valuable input, 6BG6GA.
*edit* One more question! How would you treat the 1578 tubes when building the Aikido? I have a document that outlines the circuits' resistor and capacitor specs on a per-tube basis... would I build the circuit setup for 6CG7/6CG7?
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One more question! How would you treat the 1578 tubes when building the Aikido? I have a document that outlines the circuits' resistor and capacitor specs on a per-tube basis... would I build the circuit setup for 6CG7/6CG7
I use the same setup with the 1578's as I do 6SN7 or 5692. The 6CG7/6FQ7 is supposed to be the same as the 6Sn7.
It would be interesting to see if there were any gains to be made using a regulated supply such as Frank has. I think in this application with an Aikido that you might not be able to hear differences because of the power supply rejection capabilities of the circuit.
One more question! How would you treat the 1578 tubes when building the Aikido? I have a document that outlines the circuits' resistor and capacitor specs on a per-tube basis... would I build the circuit setup for 6CG7/6CG7
I use the same setup with the 1578's as I do 6SN7 or 5692. The 6CG7/6FQ7 is supposed to be the same as the 6Sn7.
It would be interesting to see if there were any gains to be made using a regulated supply such as Frank has. I think in this application with an Aikido that you might not be able to hear differences because of the power supply rejection capabilities of the circuit.
Hi,
Your instinct is telling you something, isn't it?
Ciao,
Hi Frank!
It's telling me that I'm an engineering nerd, by wanting to combine the two complex bits of each build!
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You guy's are talking phono (MM, MC) preamps or just line stages here?
We are talking line stages. If we were talking MM or MC phono preamps I would have recommended your design of preamp with your multiple power supplies.
From personal experience with the Aikido I don't think that a regulated supply would be of a benefit because of the cancellation of the power supply noise in the Aikido circuit.
With your circuit Frank I could tell a difference just using a shunt VR regulated design. To me this means a difference with a good regulated design in my opinion.
You guy's are talking phono (MM, MC) preamps or just line stages here?
We are talking line stages. If we were talking MM or MC phono preamps I would have recommended your design of preamp with your multiple power supplies.
From personal experience with the Aikido I don't think that a regulated supply would be of a benefit because of the cancellation of the power supply noise in the Aikido circuit.
With your circuit Frank I could tell a difference just using a shunt VR regulated design. To me this means a difference with a good regulated design in my opinion.
That's the tradeoff- the Aikido has good power supply rejection, but at the expense of more tubes. A more basic circuit will have worse PSR, transferring the complexity to the power supply. Take your choice.
The PSR of the topology Frank uses can be greatly improved, in fact made better than the Aikido, but there's a parts-count penalty for doing so.
Hi,
What SY says is correct for the MM preamp part. That's the part that benefits most from a band aid such as a well regulated supply.
Not the MC part and certainly not the White CF which sports excellent PS rejection by design and a 0.1 gain loss...
Unless you'd want a buffered volume control to drive longish capacitive ICs and want to build my ultimate CD volume control using "sucker" parts (just kidding), there is little point in going overboard on the PSU for that section.
The line level preamp will be as transparant as the sum of the parts used. A mild insertion loss (gainwise) but that's all there is to it.
A transparancy from the volume control nowhere near anything you ever heard. There you go, high end audio for not exactly peanuts but at least you know which way to look.
Ciao,
What SY says is correct for the MM preamp part. That's the part that benefits most from a band aid such as a well regulated supply.
Not the MC part and certainly not the White CF which sports excellent PS rejection by design and a 0.1 gain loss...
Unless you'd want a buffered volume control to drive longish capacitive ICs and want to build my ultimate CD volume control using "sucker" parts (just kidding), there is little point in going overboard on the PSU for that section.
The line level preamp will be as transparant as the sum of the parts used. A mild insertion loss (gainwise) but that's all there is to it.
A transparancy from the volume control nowhere near anything you ever heard. There you go, high end audio for not exactly peanuts but at least you know which way to look.
Ciao,
Just to be clear, we're talking about the line amp. If the cathode of the voltage amp is held at AC ground and the plate load is made high (a CCS, a gyrator, or a good plate choke, for example), the PSR of the first stage can be increased. For example, if you use two red LEDs to bias the cathode and a CCS with a 50M impedance (easy to do), you'll get about 75dB more PSR. The CF will then be the limitation, with a PSR of roughly 26dB. That can be improved by bootstrapping via another tube section or a MOSFET.
please show me the way!
SY, I hear you but I can't understand what you are saying. Would elaborate for me? What i am hearing is to trap 2 diodes for each cathode instead of a Rk. Am I hearing you right? If so what type of LEDs?
Further, what do you mean by 50M impedance?
I am not getting what you are saying. ..Your lips move but I can't hear what your saying
I ... have become...
Thank you!
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For example, if you use two red LEDs to bias the cathode and a CCS with a 50M impedance (easy to do)SY, I hear you but I can't understand what you are saying. Would elaborate for me? What i am hearing is to trap 2 diodes for each cathode instead of a Rk. Am I hearing you right? If so what type of LEDs?
Further, what do you mean by 50M impedance?
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That can be improved by bootstrapping via another tube section or a MOSFETI am not getting what you are saying. ..Your lips move but I can't hear what your saying
I ... have become...Thank you!
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Indeed! You have a great memory! It sounds very neutral. I like it a lot. Here is the link.
http://www.diyaudio.com/forums/tubes-valves/30538-riaa-linestage-life-time.html
I now want to build a different one. The joy of being a diyer!
BTW, I ended up using a step attenuator instead of the 100k input log.
Me too! It's not about your explanation, it's about my ignorance in the subject matter. I am reading it.
BTW. Are you the author of this article? Wow, incredible!
Thanks Sy!
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