I would pay a small premium to help the designer lower costs. I prefer PCB over P to P.
Regards,
Dan
Anyone thinking about F6 PCBs?
Regards,
Dan
Attachments
O.K. here comes the minority report for ZM....
ISKRA has lowest THD in my measurements, a small bit lower than Jensen....
means 0,004% smaller....
because k2 is still lower than the k2 of Jensen. Buzz said this could be sign of the similarity of windings....
k3 is a bit higher than the k3 of Jensen....
so if I increase the k2 to surpass the k3 about 6db I get with the ISKRA a bit more THD than with the Jensen, that may be the reason I find the ISKRA a bit more detailed and less dry.
ISKRA has lowest THD in my measurements, a small bit lower than Jensen....
means 0,004% smaller....
because k2 is still lower than the k2 of Jensen. Buzz said this could be sign of the similarity of windings....
k3 is a bit higher than the k3 of Jensen....
so if I increase the k2 to surpass the k3 about 6db I get with the ISKRA a bit more THD than with the Jensen, that may be the reason I find the ISKRA a bit more detailed and less dry.
I hope you will like PtP.....!
Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2....
May I all ask again....?
The original circuit Nelson gave us had in my build k3 and k2 on the same level,
is this intended or due to my build and parts?
Shouldn't k2 be dominant per se? My second channel even had k3 higher than k2.
Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2....
May I all ask again....?
The original circuit Nelson gave us had in my build k3 and k2 on the same level,
is this intended or due to my build and parts?
Shouldn't k2 be dominant per se? My second channel even had k3 higher than k2.
Common F6 schematic suggested
I suggest that we agree on a common F6 schematic, including optional parts (like Zen pots) so that we can refer to components unambiguously. The component values do not necessarily need to be shown, only the component identifiers, like R1 and P3.
The main divergence might be in the area of the bias circuits and voltage generators for the input followers.
Any opinions?
I suggest that we agree on a common F6 schematic, including optional parts (like Zen pots) so that we can refer to components unambiguously. The component values do not necessarily need to be shown, only the component identifiers, like R1 and P3.
The main divergence might be in the area of the bias circuits and voltage generators for the input followers.
Any opinions?
Can we use the official schematic as a basis for a PCB for the masses? There will alway be others that customize and diverge from the original. Perhaps a base motherboard with daughterboards for options? Too elaborate?
Regards,
Dan
What official schematic? The only schematic from Papa since post #1 (and a later correction) is a photo of the projection screen at BAF. In any case, these schematics do not provide enough common options for DIYers to experiment with.
Can we use the official schematic as a basis for a PCB for the masses? There will alway be others that customize and diverge from the original. Perhaps a base motherboard with daughterboards for options? Too elaborate?
Regards,
Dan
didn't we put enough variables already ?
perfect tutorial to everyone to make his own drek
Dan - here is da link : http://www.diyaudio.com/forums/pass-labs/216616-f6-amplifier-130.html#post3225569
and pic :
perfect tutorial to everyone to make his own drek
Dan - here is da link : http://www.diyaudio.com/forums/pass-labs/216616-f6-amplifier-130.html#post3225569
and pic :
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from generg
"I hope you will like PtP.....!
Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2...."
thanks generg - I will be trying it this weekend and then see if I can shorten leads, etc - I want to build on a set of Jensens to compare. I will then re-read the fine tuning info and see what I can do
"I hope you will like PtP.....!
Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2...."
thanks generg - I will be trying it this weekend and then see if I can shorten leads, etc - I want to build on a set of Jensens to compare. I will then re-read the fine tuning info and see what I can do
from generg
"Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2...."
I went back and read the zen pot info as well as all I could find on the F5s P3
generg referring to post 2837 - am I correct in saying you are suggesting a 500 or 1k pot across pins 5 and 7 of the transformer
Thanks
Bob
"Do not forget to put an 500R or 1k pot nearby to put it parallel to the upper secondary if you should need some more k2...."
I went back and read the zen pot info as well as all I could find on the F5s P3
generg referring to post 2837 - am I correct in saying you are suggesting a 500 or 1k pot across pins 5 and 7 of the transformer
Thanks
Bob
yes around these values, 500R to 1000R and I recommend you to look at Ihquams experiments with this, he did all months earlier....
and really adding 8-12 db higher k2 than k3 is for me substantial to get the best out of the circuit so the pots are a must for me!