Hi everyone,
I have bought a very inexpensive chinese tube preamp that uses two 6J1 tubes. I would like to know what tubes I can buy to substitute the chinese tubes since many people say they aren't good. Any help is appreciated. Thanks
I have bought a very inexpensive chinese tube preamp that uses two 6J1 tubes. I would like to know what tubes I can buy to substitute the chinese tubes since many people say they aren't good. Any help is appreciated. Thanks
I have the same preamp. I put Russian 6J5P that is better variant and with more mu. I used for preamp for PP KT88.
Hello,
I bought a 6J1 tube buffer
(Ac 12v 1a 6j1 value preamp tube preamp amplifier board preamplifier module pre-amp headphone preamp bile buffer diy kits stereo bass hifi x10-d Sale - Banggood.com)
it sounds good when attached to an integrated amplifier but it can't drive 32 ohm earbuds. What could be the easiest mod to make it able to drive earbuds?
Thanks
I bought a 6J1 tube buffer
(Ac 12v 1a 6j1 value preamp tube preamp amplifier board preamplifier module pre-amp headphone preamp bile buffer diy kits stereo bass hifi x10-d Sale - Banggood.com)
it sounds good when attached to an integrated amplifier but it can't drive 32 ohm earbuds. What could be the easiest mod to make it able to drive earbuds?
Thanks
@R Kneck thanks for your reply, but my idea was to leave the board as it is and add some solid state components at the output, between the board and the earbuds, for being able to use earbuds.
Thanks
Thanks
6J1=6Ak5,5654,EF95,CV4010.M8100.
U can also try 6EA5,6EW6,6FG5,6GU5,6JH6,6FG5.
6AK6,6AH6,6AG5,6BA6,6BH6,6CB6,
U can also try 6EA5,6EW6,6FG5,6GU5,6JH6,6FG5.
6AK6,6AH6,6AG5,6BA6,6BH6,6CB6,
Not an exact equivalent of the 6AK5/6J1P-EV family (altough,the same pinout) ,but 9001 is another good candidate (if it happens to have a pair in your NOS collection)
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Hi all,
I need a bit of help to detail the design of small signal pentode stage design.
I have merlin blencoes books,also Richard Kuehnel' offerings,which are excellent,however,sometimes only raw numerical data is available and without mutal transfer curve info for Vg2 x -Vg1 at fixed Va for Ia the process cannot be done using the afore mentioned authors methods,two tubes i want to use for now are the EF95(6AKG6,6j1p) and CK5702(soviet 6zh1b) pentodes,as for the EF86 tube this has plenty of documentation to use either method,but when no or very limited curve data is provided its not so clear,Any help?.
I need a bit of help to detail the design of small signal pentode stage design.
I have merlin blencoes books,also Richard Kuehnel' offerings,which are excellent,however,sometimes only raw numerical data is available and without mutal transfer curve info for Vg2 x -Vg1 at fixed Va for Ia the process cannot be done using the afore mentioned authors methods,two tubes i want to use for now are the EF95(6AKG6,6j1p) and CK5702(soviet 6zh1b) pentodes,as for the EF86 tube this has plenty of documentation to use either method,but when no or very limited curve data is provided its not so clear,Any help?.
Small-signal pentode stages are conveniently designed from tube maker RC-amplifier tables (pick a similar tube if yours is not listed), then adjusted with resistance boxes.
Vg2/Vg1 is "triode Mu, typically 10 to 40, and typically quite constant with current and voltage.
Ik/Vg2 tends to obey Child's Law near-enough for initial design.
None of the small pentodes is "magic". Few cost more than $10. Do not look to odd types, but use the ones which are well documented. (If there is little documentation, it could be that the tube was not as good as others so was not popular.
Vg2/Vg1 is "triode Mu, typically 10 to 40, and typically quite constant with current and voltage.
Ik/Vg2 tends to obey Child's Law near-enough for initial design.
None of the small pentodes is "magic". Few cost more than $10. Do not look to odd types, but use the ones which are well documented. (If there is little documentation, it could be that the tube was not as good as others so was not popular.
tube data
Like i mention,It's about using the data ,i'm a first year technician,i need to have a calculation string method,such as merlin blencoe and richard kuehnel describe,they both use some form of graphic illustration to find the needed data,however,since some sellers of tubes give raw data numerically ie ,ra,mu,gm,Ia,Va etc there would then(logically) be a method to form the basis of support circuitry to run the tube from the given numerical data.
Yes,better choice of tubes with more expansive data sheet info would make things easier,but if the tube is not entirely exotic in function and follows a general pattern of operation ie a basic small signal pentode whether remote or sharp cut off types,again i would expect there to be a reasonable method to create component values,even if the need to rescale values to new current or voltage environs is needed.
This is a new endeavour for me with the design of small signal pentode circuitry,as for the ubiquitous triode circuits used in audio signal chains or the power pentode output stages(which i mostly use power dissipation with load line info combined) is no big deal.
I will continue to dig around,but it seems little is written so far as i can accertain,and the best source will be from seasoned users of the small signal pentode.
Thanks for your input, it is most appreciated.
Like i mention,It's about using the data ,i'm a first year technician,i need to have a calculation string method,such as merlin blencoe and richard kuehnel describe,they both use some form of graphic illustration to find the needed data,however,since some sellers of tubes give raw data numerically ie ,ra,mu,gm,Ia,Va etc there would then(logically) be a method to form the basis of support circuitry to run the tube from the given numerical data.
Yes,better choice of tubes with more expansive data sheet info would make things easier,but if the tube is not entirely exotic in function and follows a general pattern of operation ie a basic small signal pentode whether remote or sharp cut off types,again i would expect there to be a reasonable method to create component values,even if the need to rescale values to new current or voltage environs is needed.
This is a new endeavour for me with the design of small signal pentode circuitry,as for the ubiquitous triode circuits used in audio signal chains or the power pentode output stages(which i mostly use power dissipation with load line info combined) is no big deal.
I will continue to dig around,but it seems little is written so far as i can accertain,and the best source will be from seasoned users of the small signal pentode.
Thanks for your input, it is most appreciated.