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1. I alterated the 5F1 to feature two volume pots, one after 1st triode and next after second triode, both pots 1M audio
2. yet the second 1M pot is a substitute for the 220K resistor shown in the 5F1 schematic
3. Does this restrict the "breathability" of the 1st triode stage output, seeing a bigger impedance into ground? Hence the output will swing larger amplitudes?
4. I inserted a 1K resistor in the feed to the power tube input
1. I alterated the 5F1 to feature two volume pots, one after 1st triode and next after second triode, both pots 1M audio
2. yet the second 1M pot is a substitute for the 220K resistor shown in the 5F1 schematic
3. Does this restrict the "breathability" of the 1st triode stage output, seeing a bigger impedance into ground? Hence the output will swing larger amplitudes?
4. I inserted a 1K resistor in the feed to the power tube input
Assuming we are talking about Fender Champ-amp 5F1 with cathode-biased 6V6, the 1M pot that replaces 220k resistor is exceeding the maximum allowed Grid Number 1 Circuit Resistance value on the 6V6 data sheet (max is 500k). Not sure if this has any other negative effect but blocking distortion will take longer to resolve.
http://www.r-type.org/pdfs/6v6gt.pdf
1. Ok..
2. See explanation above
3. Swing amplitude should be the same as it is determined more by the 100k resistor on the 12AX7 plate
4. A grid stopper resistor? That's ok.
This should be in the instrument section.
http://www.r-type.org/pdfs/6v6gt.pdf
1. Ok..
2. See explanation above
3. Swing amplitude should be the same as it is determined more by the 100k resistor on the 12AX7 plate
4. A grid stopper resistor? That's ok.
This should be in the instrument section.
Parallelled 334 resistor with 2nd pot, effective resistance then 224.
Could swap 2nd 105 pot with 254 pot
Any harm as is without reducing resistance of the 2nd stage 105pot?
Could swap 2nd 105 pot with 254 pot
Any harm as is without reducing resistance of the 2nd stage 105pot?
To keep it closer to stock, just use a 250k audio taper pot before the 6V6 in place of the 220k resistor. If you want more gain , try a 500k and see what happens. As ballpencil points out, 500k ohm in max for cathode bias 6V6 for the grid circuit.
Essentially both are saying the 105pot is killing the class A 6v6 by allowing inadequate temperament.
Instead I bridged the 105pot with a 105 1/4watt metalfilm, and boy did luscious bass unfold.
This satisfies the 474 tiedown max of input into 6v6.
Next alteration, install cathode bypass cap onto 2nd stage ecc83, why, need overdrive sound, wet and sticky. 1st stage I see 25uf, but 2nd stage there is nothing.
Can also swap out cathode bias resistors ecc83, replace 152 with 821, both triodes, ecc83 runs hotter reactionary.
Instead I bridged the 105pot with a 105 1/4watt metalfilm, and boy did luscious bass unfold.
This satisfies the 474 tiedown max of input into 6v6.
Next alteration, install cathode bypass cap onto 2nd stage ecc83, why, need overdrive sound, wet and sticky. 1st stage I see 25uf, but 2nd stage there is nothing.
Can also swap out cathode bias resistors ecc83, replace 152 with 821, both triodes, ecc83 runs hotter reactionary.
I'm sorry, I don't know what you mean by 105pot. And replace 152 with 821. Maybe it would be easier to just state 100k ohm or 820 ohm. I have never seen these descriptions. Is 152 a 15 and two zeroes meaning a 1500 ohm resistor and 821 an 82 with one zero meaning 820 ohm? This does make sense but I have never seen it before. And 105 pot a 1 meg pot? 10 with five more zeroes?
105, 152 etc usually refers to Capacitors--They are often marked as such. Only Surface-Mount fixed resistors are marked, 105 etc....
You defo wouldn't be using SM resistors in a tube-amp.....
105pot I'm assuming O/P means 1 Meg log taper pot....
You defo wouldn't be using SM resistors in a tube-amp.....
105pot I'm assuming O/P means 1 Meg log taper pot....
yeah, shorthand applies all discrete, not necessarily smd.
good you folks fender legacy familiarized typical ecc83 triode cathode bias resistor and bypass cap values, 1K5 and 25uf, versus british highend topology .68uf 820R
emitter resistors low values typically designated R22, R33
and silvermica 1n0, 221, 103 etc.
mil pots have stamped indication, 105, 254, same as slm, peavey, fender "inhouse" designators
but if pot taper clueless, tone is ALWAYS logarithmic but level can be EITHER B or A
log merely delays the rise of level as one dials upwards, but I have no experience with log reversal - maybe its abrupt?
gotta wiper bridge the 2nd pot (master) with 221 silver mica, then try 1n0, not that present signature is weak on upper register, but to realize the significance of the old giant box sealed sanyo threeway (12",6",3", all paper construct, all construct fabric surround spider too, all eight ohm, all alnico, all 25rms handling, 1960's era, not one indication corrosion, 3" has local bp protector, I wired 12"&6" series so 16impedance, 3" piggybacks parallel onto 6", so overall impedance pseudo 12impedance?).
the lespaul sounds impressive (p90) but the tele is just too too twangy (country western), so need some kind of 5F1 internal switch to jump gain for tele, maybe swapping 1st stage ecc83 cathode resistor with K82 and simultaneously engaging 25uf cathode bypass onto ecc83 2nd stage, and even swapping slope resistor (less restrictive more punch) dangerous voltage present and routed to panel switch
good you folks fender legacy familiarized typical ecc83 triode cathode bias resistor and bypass cap values, 1K5 and 25uf, versus british highend topology .68uf 820R
emitter resistors low values typically designated R22, R33
and silvermica 1n0, 221, 103 etc.
mil pots have stamped indication, 105, 254, same as slm, peavey, fender "inhouse" designators
but if pot taper clueless, tone is ALWAYS logarithmic but level can be EITHER B or A
log merely delays the rise of level as one dials upwards, but I have no experience with log reversal - maybe its abrupt?
gotta wiper bridge the 2nd pot (master) with 221 silver mica, then try 1n0, not that present signature is weak on upper register, but to realize the significance of the old giant box sealed sanyo threeway (12",6",3", all paper construct, all construct fabric surround spider too, all eight ohm, all alnico, all 25rms handling, 1960's era, not one indication corrosion, 3" has local bp protector, I wired 12"&6" series so 16impedance, 3" piggybacks parallel onto 6", so overall impedance pseudo 12impedance?).
the lespaul sounds impressive (p90) but the tele is just too too twangy (country western), so need some kind of 5F1 internal switch to jump gain for tele, maybe swapping 1st stage ecc83 cathode resistor with K82 and simultaneously engaging 25uf cathode bypass onto ecc83 2nd stage, and even swapping slope resistor (less restrictive more punch) dangerous voltage present and routed to panel switch
background communist 5F1 chrome chassis complete:
the tranny ot is edcor eight ohm 8K5 primary, 18rms (removed Chinese ot multitap)
but pt is genuine communist, quite large for a mere 6v6 se, so it is very good does not get warm, has cooling.
pt 2nd'arys besides htrs 5y3 and 6.3vac, the ht is switchable by threeway switch 330vac😱ff:300vac
internal microswitch utilized for disengaged negfdbk
internal microswitch used to disengage piggyback 470uf onto 6v6 cathode bypass legacy 25uf
ALL PT energy switches config are double poled and thrown as double, MAYBE this creates horrendous flybacks (i.e., reactive currents from inductive storage) when switching "live"
the tranny ot is edcor eight ohm 8K5 primary, 18rms (removed Chinese ot multitap)
but pt is genuine communist, quite large for a mere 6v6 se, so it is very good does not get warm, has cooling.
pt 2nd'arys besides htrs 5y3 and 6.3vac, the ht is switchable by threeway switch 330vac😱ff:300vac
internal microswitch utilized for disengaged negfdbk
internal microswitch used to disengage piggyback 470uf onto 6v6 cathode bypass legacy 25uf
ALL PT energy switches config are double poled and thrown as double, MAYBE this creates horrendous flybacks (i.e., reactive currents from inductive storage) when switching "live"
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