Again.. just have to add how the 'lick' captures pretty much all of the guitars sweet harmonics, using pulls and hammers, accenting lows and highs, and generally covering full tones. Great sounding amp my friend.
I just bought a bunch of vishay electrolytics at mouser per your recommendation and the 10ufs 100v caps they sent me are significantly smaller then the ones in youre video. Theyre identical in size to the 25uf 63v. They are indeed labeled at 100v. Am I missing something. Also Ive only ever seen 160v or greater used in the bias section. My negative voltage is 53v am I correct in my thinking that this means I have 47v of safety margin here and that this is just another example of Marshall using what was available for the right price?
@@PsionicAudio Lyle I truly appreciate you taking the time to respond to my questions on Sunday of all days. I get so much out of youre videos. They've really helped me wrap my brain around areas that I just painted by numbers on up until now. Thank for all you do!
If an amp like this was optimized/born with EL-34's.......What happens if you install 6550's? Where will the bias end up with the 6550's? Too hot, to cold ect.....Does any part/values need to be changed when going from EL-34's to ➡️ 6550's?
You have to adjust the bias and a few other minor things. Having done two almost identical '76 2204s, one with 34s and the other with 6550s, when both amps were biased the same the differences were minor in the extreme.
@@PsionicAudio Wow 😳....thanks for the reply.....love this channel. I have a quad of 6550's I'd like to use up....... while riding out the tube crisis of 2022 😁.
Sounding great! So, in my JMP 2203, I think someone tried to do the same trick by adding a resistor in parallel to adjust the bias range, but they did it to the next resistor down (which I think is a 15k). The tech working on my amp right now said that was a mistake... do you know what that would actually do?
Say it's a standard Marshall bias supply with a 15K between caps then a 47K and a 22k pot in series to ground. That whole thing is a voltage divider with the top part of the divider bring 15K, and the bottom varying between 47K and 69K. To change the divider you can change either value. So you could increase or decrease the top 15K while leaving the bottom value as-is. BUT in this case the top value is also decoupling between the two filter caps. So because reasons you really don't want to change the top value, so leave it at 15K. That really leaves you with changing the 47K as the best option. Increase it to make the overall available bias voltage more negative. Decrease it to do the opposite. There's more to it than that but that's the gist.
@@PsionicAudio Thanks for this information! I'm in the process of changing my Super Lead kit to 6550:s to play bass with. I want all the clean punch that I can get out of it. It sounds awesome already with the mismatched EL34:s in place.
I can clearly see the color bands on that resistor and it should be a 47K. I am not color blind. If it has drifted as far as 56K maybe you should consider changing it. (This not an "ackshually") 😁
I have a hard time hearing the tone of an amp when you use positions 2 or 4 on a strat as it always sounds too tinkly and pinched. This probably annoys you so I will apologize in advance. Lol Not easy to tell good tone in those positions....Too samey. ;)
I'm particularly interested in the way an amp sounds with a Strat in position 2. The comb filtering is where I live most of the time when not playing a guitar with HBs. I think Lyle using a variety of combinations is a good thing. A little something for everyone.
@@retread1083 Yes I agree he did here. But he doesn't always. lol He likes that 2nd position an awful lot. But hey it's his show. I was just asking more than anything and saying what's on my mind. Lyle is awesome and I appreciate everything he shares. Thanks for your input.
Thank you for using other positions on this video. Always listening and learning.
My favorite amp of all time, prefer 6550s myself (I know, unpopular) for the tighter bass and in your face power amp distortion.
Again.. just have to add how the 'lick' captures pretty much all of the guitars sweet harmonics, using pulls and hammers, accenting lows and highs, and generally covering full tones. Great sounding amp my friend.
Excellent! I like the piggybacking of resistors. It's an easily reversible mod. How many mA do you like to see on an EL34?
Bias is idle dissipation that requires the plate voltage and current to be known. You can’t just turn a screwdriver to set one or the other.
Safe operational range is between 10-40mA per tube. Read; The Trainwreck Pages by Ken Fischer, lots of great stuff on bias, etc.
@@matthewf1979 Well an oscilloscope and a signal generator can help you determine that too.
Have you noticed much difference in the tones of the older 2203’s and the newer reissues ?
Love the channel, BTW….
I didn't. I just sold my '83 2203 and kept the 2203X.
I just bought a bunch of vishay electrolytics at mouser per your recommendation and the 10ufs 100v caps they sent me are significantly smaller then the ones in youre video. Theyre identical in size to the 25uf 63v. They are indeed labeled at 100v. Am I missing something. Also Ive only ever seen 160v or greater used in the bias section. My negative voltage is 53v am I correct in my thinking that this means I have 47v of safety margin here and that this is just another example of Marshall using what was available for the right price?
Sorry -53vdc lol
100V is fine. Vishay has several different series, some are larger than others. All their 100V axials are fine for bias though.
@@PsionicAudio Lyle I truly appreciate you taking the time to respond to my questions on Sunday of all days. I get so much out of youre videos. They've really helped me wrap my brain around areas that I just painted by numbers on up until now. Thank for all you do!
If an amp like this was optimized/born with EL-34's.......What happens if you install 6550's? Where will the bias end up with the 6550's? Too hot, to cold ect.....Does any part/values need to be changed when going from EL-34's to ➡️ 6550's?
You have to adjust the bias and a few other minor things. Having done two almost identical '76 2204s, one with 34s and the other with 6550s, when both amps were biased the same the differences were minor in the extreme.
@@PsionicAudio Wow 😳....thanks for the reply.....love this channel. I have a quad of 6550's I'd like to use up....... while riding out the tube crisis of 2022 😁.
Sounding great!
So, in my JMP 2203, I think someone tried to do the same trick by adding a resistor in parallel to adjust the bias range, but they did it to the next resistor down (which I think is a 15k). The tech working on my amp right now said that was a mistake... do you know what that would actually do?
Say it's a standard Marshall bias supply with a 15K between caps then a 47K and a 22k pot in series to ground.
That whole thing is a voltage divider with the top part of the divider bring 15K, and the bottom varying between 47K and 69K.
To change the divider you can change either value. So you could increase or decrease the top 15K while leaving the bottom value as-is.
BUT in this case the top value is also decoupling between the two filter caps. So because reasons you really don't want to change the top value, so leave it at 15K.
That really leaves you with changing the 47K as the best option. Increase it to make the overall available bias voltage more negative. Decrease it to do the opposite.
There's more to it than that but that's the gist.
@@PsionicAudio Thanks for the explanation!
@@PsionicAudio Thanks for this information!
I'm in the process of changing my Super Lead kit to 6550:s to play bass with. I want all the clean punch that I can get out of it. It sounds awesome already with the mismatched EL34:s in place.
I can clearly see the color bands on that resistor and it should be a 47K. I am not color blind. If it has drifted as far as 56K maybe you should consider changing it. (This not an "ackshually") 😁
62K in parallel with 47K = 26,730 or so.
I have a hard time hearing the tone of an amp when you use positions 2 or 4 on a strat as it always sounds too tinkly and pinched. This probably annoys you so I will apologize in advance. Lol Not easy to tell good tone in those positions....Too samey. ;)
I'm particularly interested in the way an amp sounds with a Strat in position 2. The comb filtering is where I live most of the time when not playing a guitar with HBs. I think Lyle using a variety of combinations is a good thing. A little something for everyone.
@@retread1083 Yes I agree he did here. But he doesn't always. lol He likes that 2nd position an awful lot. But hey it's his show. I was just asking more than anything and saying what's on my mind. Lyle is awesome and I appreciate everything he shares. Thanks for your input.