Hi All,
Have this next build in the works that clones Andres' upgrades to the Eico ST70 - http://www.tronola.com/html/st-70_hotrod.html
It was discussed on this forum - https://www.diyaudio.com/community/threads/eico-st-70-supermods.196790/
This will be clean sheet build using schematic from Andres, not a modified original ST70. I'll be using 6gm5's in place of 7591's.
I feel pretty confident that substitution.
I plan to evaluate performance similar to steps outlined in article to verify substitutions, once biases and balance settings are achieved.
Design question- Can I use single 6U10 ( 2 low mu, one hi mu triodes) to replace (2) 6sn7 and (1) 12ax7? https://tube-data.com/sheets/123/6/6U10.pdf
Related question- Are interelectrode capacitances important factors to compare when substituting tubes in design? If not, are there other chart characteristics besides Typical, Maximum Voltages and Gain that I should compare?
Thanks,
Jim
Have this next build in the works that clones Andres' upgrades to the Eico ST70 - http://www.tronola.com/html/st-70_hotrod.html
It was discussed on this forum - https://www.diyaudio.com/community/threads/eico-st-70-supermods.196790/
This will be clean sheet build using schematic from Andres, not a modified original ST70. I'll be using 6gm5's in place of 7591's.
I feel pretty confident that substitution.
I plan to evaluate performance similar to steps outlined in article to verify substitutions, once biases and balance settings are achieved.
Design question- Can I use single 6U10 ( 2 low mu, one hi mu triodes) to replace (2) 6sn7 and (1) 12ax7? https://tube-data.com/sheets/123/6/6U10.pdf
Related question- Are interelectrode capacitances important factors to compare when substituting tubes in design? If not, are there other chart characteristics besides Typical, Maximum Voltages and Gain that I should compare?
Thanks,
Jim
Hi Jim,
I'd say yes, triode 1&3 can replace the 6SN7, section 2 one half 12AX7.
WHile the heater is common, there should not be an issue elevating it a bit.
I'd say yes, triode 1&3 can replace the 6SN7, section 2 one half 12AX7.
WHile the heater is common, there should not be an issue elevating it a bit.
JC-
Thanks for valued opinion. I've done a PC layout including the 6U10, but wanted to ask the brain trust here before investing forward.
What do you mean about 'elevating it a bit'? Perhaps the heater voltage?
Jim
Thanks for valued opinion. I've done a PC layout including the 6U10, but wanted to ask the brain trust here before investing forward.
What do you mean about 'elevating it a bit'? Perhaps the heater voltage?
Jim
