That takes us back to some of the earlier comments. OLD is not always BEST. EXPENSIVE is not always BEST.
Some of the QUAD equipment is classed as Hi-End but it is poor when compared to other equipment that is available.
Some people just like the sound of certain equipment. That is why I keep saying - Try It and Take Youe Ears Shopping.
Depends on the valves you want use. The choice of the base shape is immaterial.
In the transistor World there is a valid argument between TO3 and TO220 due to the transfer of heat from one case type to the heatsink against another, in the valve World it makes not a happenyworth of difference.
In the transistor World there is a valid argument between TO3 and TO220 due to the transfer of heat from one case type to the heatsink against another, in the valve World it makes not a happenyworth of difference.
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I think you are probably right KatieandDad. It's pretty hard to audition tube preamps though, esp where I live. I pretty much have to buy to try. But it seems more sensible to build your own, such as with the Aikido, then try building another one, etc., while developing some knowledge of WHY this one sounds this way while that one sounds that way, in terms of the topology.........rather than spend 1000 for this preamp, then 1000 for that preamp, with no idea of what makes them sound the way they do, but rather your understanding of the cause of preamp character is more like "ARC sounds neutral, CJ sounds fat and warm, and when I sell my ARC and CJ, I'll tell you about the sound of VTL, Audible Illusions, Joule-Electra, etc etc"
So put me in the DIY camp. I do hope however that the Aikido is not so modern that it is completely neutral, or lacking any tube bloom and warmth. I just need less warmth than I currently have with my vintage stuff.
Jim
OK, let me rephrase that....
any thoughts on whether I should go with 9-pin tubes, or octal tubes, for my preamp? People seem to like both...
Jim
Most Pre-Amps will use a similar Vcc so once you have gone to the expense of buying the mains transformer that will not be wasted.
If you want something that is less warm, why are you going down the tube route.
I built a Hi-End ECC82/3 pre-amp that was so disappointing, based on a Borbelli design. The guy I sold it to thought it was the BEST amplifier that he had ever heard.
Even the designer thought I was crazy using his 1960's design.
If you want something that is less warm, why are you going down the tube route.
I built a Hi-End ECC82/3 pre-amp that was so disappointing, based on a Borbelli design. The guy I sold it to thought it was the BEST amplifier that he had ever heard.
Even the designer thought I was crazy using his 1960's design.
OK, let me rephrase that....
any thoughts on whether I should go with 9-pin tubes, or octal tubes, for my preamp? People seem to like both...
Jim
It makes absolutely no difference whether you use one type of tube with an Octal or 9-Pin base.
Your question should be - what type of tubes should I be looking at - again a very subjective question.
It's a matter of degree. I want a more clear neutral sound than I have now, but I will want tube character.
What's Vcc?
Jim
Your latter question is what I am trying to say. Is it correct that 6SN7 is octal, while 12AX7 and 5751 are nine-pin? That would let me research what people say about these tubes....
Thanks,
Jim
Sorry but I give up. If you don't know what Vcc means I would not be building anything.
I'll say it AGAIN and AGAIN. It makes NO DIFFERENCE what type of valve base you choose to use.
Choose which type of valve you want to use and that will decide the base that you need.
There IS a difference between CERAMIC and PLASTIC valve bases, TIN and GOLD contacts. But Octal and 9-Pin are both available in all sorts of materials.
I'll say it AGAIN and AGAIN. It makes NO DIFFERENCE what type of valve base you choose to use.
Choose which type of valve you want to use and that will decide the base that you need.
There IS a difference between CERAMIC and PLASTIC valve bases, TIN and GOLD contacts. But Octal and 9-Pin are both available in all sorts of materials.
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I guess it's not a DIY question, so I posted this over there...maybe this will be a better effort on my part to explain what I'm trying to find out about. Thanks again all.
Amp/Preamp Asylum
Jim
Amp/Preamp Asylum
Jim
OK, thanks. So would it be correct that the 9-pin version of the Aikido is intended for people that want to use the 12AX7, and the octal is for people who want to use the 6SN7?
If one bought the 9-pin version of the Aikido, could one use other tubes besides the 12AX7, such as the 5751, or even other tubes, such that one could lump them all together as "the 9-pin preamp tubes?" or does that also make absolutely no sense?
I was trying to lump together 9-pin preamp tubes, and octal preamp tubes, into two categories, and asking if in general, the two categories had different characteristics, as a way to learn if I should get the octal or the 9-pin Aikido. I know I could have asked for a contrast between those specific tubes, but was looking for a contrast between two classes of tubes. Maybe instead of picking an Aikido based on the class of tubes that can be used in it, I should ask about specific tubes then pick the one that supports the one I go for. But if there are several possible tubes that can be used in each version, it would seem to require a lot less questions to just narrow the choice to 9-pin or octal. On the other hand, maybe I'm completely mistaken in my conception. I may be confused, and if so, can you help straighten out my question? I can certainly sympathize with the frustration that comes from explaining something to somebody who keeps asking the wrong questions becuase they don't grasp some basic aspect of the issue, and that could be me. Sorry, I'm trying.
Maybe an answer is "no, you can't lump all the 9-pin tubes together, and the octals together, and say the 9-pins sound this way, and the octals sound that way. You have to take it tube by tube. THEN pick the kit that supports what you decide on."
Thanks,
Jim
If one bought the 9-pin version of the Aikido, could one use other tubes besides the 12AX7, such as the 5751, or even other tubes, such that one could lump them all together as "the 9-pin preamp tubes?" or does that also make absolutely no sense?
I was trying to lump together 9-pin preamp tubes, and octal preamp tubes, into two categories, and asking if in general, the two categories had different characteristics, as a way to learn if I should get the octal or the 9-pin Aikido. I know I could have asked for a contrast between those specific tubes, but was looking for a contrast between two classes of tubes. Maybe instead of picking an Aikido based on the class of tubes that can be used in it, I should ask about specific tubes then pick the one that supports the one I go for. But if there are several possible tubes that can be used in each version, it would seem to require a lot less questions to just narrow the choice to 9-pin or octal. On the other hand, maybe I'm completely mistaken in my conception. I may be confused, and if so, can you help straighten out my question? I can certainly sympathize with the frustration that comes from explaining something to somebody who keeps asking the wrong questions becuase they don't grasp some basic aspect of the issue, and that could be me. Sorry, I'm trying.
Maybe an answer is "no, you can't lump all the 9-pin tubes together, and the octals together, and say the 9-pins sound this way, and the octals sound that way. You have to take it tube by tube. THEN pick the kit that supports what you decide on."
Thanks,
Jim
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Just because a tube fits in a socket does not mean that it will work properly in the circuit. The circuit is designed around the operating characteristics of a particular tube type. Also, the function of each pin can be very different from type to type -- ie. power and input signals are not always on the same pins.
Just because a tube works ( I mean makes sound come out) in a particular circuit does not mean it will sound the same as another tube in that same circuit. This is what "tube rolling" is all about... finding the brand/maker of the tube that sounds best in your system.
There is really nothing about the technology of the tube that should be driving your choice of ordering -- what should be driving your choice are the sonics of a particular tube that you know you like.
I could recommend that you build for 6922, or 12AX7 but you may not like how either of those sounds. They are sonically very different.
This is an entirely personal choice.
Just because a tube works ( I mean makes sound come out) in a particular circuit does not mean it will sound the same as another tube in that same circuit. This is what "tube rolling" is all about... finding the brand/maker of the tube that sounds best in your system.
There is really nothing about the technology of the tube that should be driving your choice of ordering -- what should be driving your choice are the sonics of a particular tube that you know you like.
I could recommend that you build for 6922, or 12AX7 but you may not like how either of those sounds. They are sonically very different.
This is an entirely personal choice.
Ah, ok, thank you. That makes my problem more clear.
I'll work on researching various tube options and understanding the topology a bit better. I guess if I'm not able to make the choice of which preamp tube to build for and how the topology relates to the tube's structure, I'm not ready to try and build a preamp. I know what three tube types are used in my preamp, but I don't know which of the three types is the one that would correspond to the tube that would guide my choice of Aikido preamp. So, more work to do.
Thanks again for the help everyone.
Jim
John at tubecad.com does the aikido boards he make some for 12ax7 9pin the 6dj8 , and 5687 family as well as the octal 6sn7 etc even 12sn7 with a heater change up on the boards look at what all he offers you will be fine using any one of his boards a great site to read also. First question is what tubes do you have a lot of ? I don't
expect you to say 40of 7236 and 100 of 7370 etc.
My take is if this from scratch a nice octal and a clean smooth power supply is a great way to start. If you have some 9 pins that ok start with one and go from there. Get your feet wet and ease in to it you don't have to hit a home run on the first try . Any where a good start just start be safe and don't sweat the small stuff.
expect you to say 40of 7236 and 100 of 7370 etc.
My take is if this from scratch a nice octal and a clean smooth power supply is a great way to start. If you have some 9 pins that ok start with one and go from there. Get your feet wet and ease in to it you don't have to hit a home run on the first try . Any where a good start just start be safe and don't sweat the small stuff.
The Aikido designs allow for the use of a range of valves - one variant of the PCB supports octal based valves, the other 9-pin valves - the circuit is essentially the same for both versions.
Once the PCB has been built to suit one particular valve (either octal or 9-pin) then it is not a simple case of being able to plug another valve in without changing some of the resistors to suit the new valve.
(BTW, loosely put, Vcc is the positive going supply rail usually in reference circuits that use BJTs - for valve based designs it is usually referred to as B+).
Andy
Once the PCB has been built to suit one particular valve (either octal or 9-pin) then it is not a simple case of being able to plug another valve in without changing some of the resistors to suit the new valve.
(BTW, loosely put, Vcc is the positive going supply rail usually in reference circuits that use BJTs - for valve based designs it is usually referred to as B+).
Andy
Thanks Triodethom and underwurlde. Back in the 90s I did some work at the VA Hospital in LA, and they were throwing away lots of old lab qear, all vacuum tube, so I robbed the tubes out of the stuff sitting on the loading docks before the trash haulers got it. I have a couple boxes of Telefunken and other 9-pins. Don't know about octals. I know there are 12AX7s, 12AU7s, and American brands. So maybe I should try for a 12AU7. Think that is one of the options? I know my CJ has 12AX7s and 5751s.
Thanks,
Jim
Thanks,
Jim
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