found this cathode follower amp, by Fletcher and Cooke
http://www.clarisonus.com/Archives/Amp_Design/Cathode_Follower_Amp.pdf
http://www.clarisonus.com/Archives/Amp_Design/Cathode_Follower_Amp.pdf
Well if you need to by all parts again for 5-15W Circlotron Amps thats bad !
Be carefull since Circlotron OPT with relative higher Z primary coil need to be formed using split bobbin coil tehnique to obtain the best electrical ( Audio ) transfer characteristic , regardless from used type of iron core form , EI or even better double C core type .
```well, every time I believe to have learned something I only find that I know nothing, or at least still not enough``` - It is the same with me sometimes !!!
Ps : here is one article link which describe many type of OTL PP topology , in beetwen Circlotron type too , with excellent circuits analysis :http://www.audiodesignguide.com/otl/aria.html
Best Regards
Be carefull since Circlotron OPT with relative higher Z primary coil need to be formed using split bobbin coil tehnique to obtain the best electrical ( Audio ) transfer characteristic , regardless from used type of iron core form , EI or even better double C core type .
```well, every time I believe to have learned something I only find that I know nothing, or at least still not enough``` - It is the same with me sometimes !!!
Ps : here is one article link which describe many type of OTL PP topology , in beetwen Circlotron type too , with excellent circuits analysis :http://www.audiodesignguide.com/otl/aria.html
Best Regards
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Think that 1,6K split bobbin coil OPT it is just OK for Circlotron 50W Amp with 2 x EL34 tube in AB1/B1 class , pentode connected , but what is the that OPT iron quadrature ? , heater trafo is Ok too , but main trafo is not OK for that Amp topology ! just need two galavanic separate secondary .
housing, cast in OPT
I think 50watt is too much for this OPT
but maybe ok in class AB, if I don't play too loud
also just now looked at power buffer amps
coupling cathodes directly to secondary
different thing tho
I will try and post about this in another thread about CFB
housing, cast in OPT
I think 50watt is too much for this OPT
but maybe ok in class AB, if I don't play too loud
also just now looked at power buffer amps
coupling cathodes directly to secondary
different thing tho
I will try and post about this in another thread about CFB
No I actually just wonder what is the effective quadrature of that OPT iron core size (Sfe ) in cm2 !?, since the effective iron core size determined lots of OPT/Amp parameters .
Interested for that power buffer amps ! I stay tuned !
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....... effective quadrature of that OPT iron core size (Sfe ) in cm2 !?
Interested for that power buffer amps ! I stay tuned !
sounds great
OPT plastik bobbin measures 68 x 74mm (see picture)
with housing and all, weighs in just above 3kilo
no point in denying it, I like to take pictures
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Interested for that power buffer amps ! I stay tuned !
I might be tempted to try somthing like this
but not much info to find
feel free to 'shoot it down'
though not a circlotron, its still 'cathode follower' output
if I know what that means
mind you, one reason is that I have those lowish impedance OT
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Moving the load from anodes to cathodes DOES NOT change the optimum load, just improves damping factor by a ratio roughly equal to the µ of the tubes.
And . . . do you really want to drive the screens ? or typo ?
If so, you will need to provide some very assymetrical screen current and that voids the use of capacitor links.
Yves.
And . . . do you really want to drive the screens ? or typo ?
If so, you will need to provide some very assymetrical screen current and that voids the use of capacitor links.
Yves.
Hi Tinitus !
Dont want to shut down your ideas but in your attached schematic I not understand two point !
1) Why you want to drive G2 from EL34 ?, since is already enough difficult to drive G1 of EL34 in CF configuration ! .
2) In that your topology you don`t need two separate B+ supply , single B+ well finish the job for sure .
Actually I think the best solution to use that your balanced 1,6K OPT is to consider to use old anode coupled Circlotron AMP topology with two separate but equal 250 - 300 VDC B +/ B`+ supply , and triode strapped both output EL34 tubes for best linearity , running than AMP`s output in A1 / AB1 class , and expecting than about 25 W of nice sounding tube Amp , since the anode coupled Circlotron use the whole OPT primary coil and need only half of conventional PP Amp primary coil impedance , your balanced 1,6K OPT impedance is very near for that purpose , or just perfect ! .
BTW , Viktor K. from BAT already successfully use that anode coupled Circlotron topology in BAT VK 60 Amp. but renamed to `` Single - Ended bridge Output Stage `` .
Here is the basic schematic :
Best Regards !
Dont want to shut down your ideas but in your attached schematic I not understand two point !
1) Why you want to drive G2 from EL34 ?, since is already enough difficult to drive G1 of EL34 in CF configuration ! .
2) In that your topology you don`t need two separate B+ supply , single B+ well finish the job for sure .
Actually I think the best solution to use that your balanced 1,6K OPT is to consider to use old anode coupled Circlotron AMP topology with two separate but equal 250 - 300 VDC B +/ B`+ supply , and triode strapped both output EL34 tubes for best linearity , running than AMP`s output in A1 / AB1 class , and expecting than about 25 W of nice sounding tube Amp , since the anode coupled Circlotron use the whole OPT primary coil and need only half of conventional PP Amp primary coil impedance , your balanced 1,6K OPT impedance is very near for that purpose , or just perfect ! .
BTW , Viktor K. from BAT already successfully use that anode coupled Circlotron topology in BAT VK 60 Amp. but renamed to `` Single - Ended bridge Output Stage `` .
Here is the basic schematic :
Best Regards !
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Just few more important points since I posted raw topology schematic :
1) From each of two floating B- supply you must put two equal ground reference resistors to Amps center ground star point to achieve ground reference points for PP driver stage , value of this two resistors is usually 5 to 10 time higher than value of EL34 self bias cathode resistors .
2) Since anode coupled Circlotron is formed from two basic grounded cathode SE Amps joined together G1/G1` driver peak voltage requirement is relative low , same as for conventional PP Amp .
3) Precaution must be present when you wiring two galvanic separate PT secondaries to the two greatz rectifier bridge , they have to be done in same manner ( in phase ), to avoid any hum & noises .
4) With fine triming value of EL34 self bias cathode resistors you well avoid any DC current to flow trough OPT primary coil under no signal condition .
Best Regards !
1) From each of two floating B- supply you must put two equal ground reference resistors to Amps center ground star point to achieve ground reference points for PP driver stage , value of this two resistors is usually 5 to 10 time higher than value of EL34 self bias cathode resistors .
2) Since anode coupled Circlotron is formed from two basic grounded cathode SE Amps joined together G1/G1` driver peak voltage requirement is relative low , same as for conventional PP Amp .
3) Precaution must be present when you wiring two galvanic separate PT secondaries to the two greatz rectifier bridge , they have to be done in same manner ( in phase ), to avoid any hum & noises .
4) With fine triming value of EL34 self bias cathode resistors you well avoid any DC current to flow trough OPT primary coil under no signal condition .
Best Regards !
noted
and then theres the contradictory thought
that with it would be convenient to feed the PP tube amp from a balanced SS preamp
Any way, why not to try that combination? ! ,
If ocasionally that SS Preamp/Tube Amp combination sonically fail here is this DIY Audio site with many interesting DIY pure Tube balanced preamps projects !
Best Regards !
yep
I will 'probably' use mostly with my now old fashioned CD machine, and it also happens to have balanced out
so yeah, why not do it
alistair, yeah, I know, need two trafos with double secondary, and will build mono amps only
I have some circlotron schematics to study, and some more
FWIW the first MA-2s (OTLs) that we made were anode-coupled rather than cathode.
something like this, in principle ?
hmm, looks almost like a blumlein thing (punctured lines)
hmm, looks almost like a blumlein thing (punctured lines)
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