jmp 50watt with magnetic components transformer set

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dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:
dukeamps wrote:
iknowjohnny wrote:Im just built a 50 watt hi gain amp with those myself. My take is PT and choke are fine. OT is ok, but i tried my hammond and heyboer on it and i think both are a bit better to my ear. But for now i'm leaving it because theres not enough difference to really matter. Later i may replace it with the heyboer or a marstran or metro, but i'm not sure yet. So far i haven't found huge differences between OT's. Enough to prefer one over the other, but not enough to really worry about it. As to the PT, i haven't played the amp loud for any length of time, but so far the PT has never gotten even warm to the touch.
Hi, I have also a 50watt with hammond pt ot & choke, And the magnetic components sounds just as good. As to the heat my hammond also gets warm. I have been using that amp for about a year now with no problems.

Thanks :)

Dukeamps
But have you tacked the others in? I have done this with the other OT's. I put a board across the chassis to set the OT on and unsoldered the OT in the amp and soldered the outboard one in real quick to get an A/B comparison not only quickly, but in the exact same amp. You can't A/B two OT's in two different amps know for sure that the diff you hear is not other contributors besides the OT. But like i said, it's not a huge difference, and i could see how it's subjective too. The hammond tho IMO was better in a less subjective way....similar, but richer and less harshness.

Hi, No i have not a/b them in the same amp, and i can understand what you are saying. It is that i have the same amp but with hammond set, and with cc resistors sozo caps the same preamp tubes, and nos mullard el34s, and the difference is not that big. I was also very surprised with how good the rft el34s are. But i think put the 2 amps in playing with a band, and nobody could hear a difference. :D

Dukeamps
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

I was also very surprised with how good the rft el34s are.
are these NOS or new tubes? I will have to look because it would be nice to find a new tube that closes the gap between new and NOS. Been crossing my fingers on that forever tho so i suppose it's not likely. And yes, no one will ever hear it. Heck, i can't even hear huge changes in my own amp when someone else is playing it ! But when it's me at the helm i hear/feel things that are otherwise extremely subtle. You gotta please yourself B4 the audience because while they can't hear the difference between OT A and OT B, they can hear it when you play great or play like sheet. And those things they can't hear you can, and can make you play to one end of the good/bad spectrum or the other. So in a way, they DO hear it, if only in your playing.
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:
I was also very surprised with how good the rft el34s are.
are these NOS or new tubes? I will have to look because it would be nice to find a new tube that closes the gap between new and NOS. Been crossing my fingers on that forever tho so i suppose it's not likely. And yes, no one will ever hear it. Heck, i can't even hear huge changes in my own amp when someone else is playing it ! But when it's me at the helm i hear/feel things that are otherwise extremely subtle. You gotta please yourself B4 the audience because while they can't hear the difference between OT A and OT B, they can hear it when you play great or play like sheet. And those things they can't hear you can, and can make you play to one end of the good/bad spectrum or the other. So in a way, they DO hear it, if only in your playing.
Hi, The tubes are nos, i think they are from the late 70s.

Dukeamps :)
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

yes, i checked them out. Not too bad as far as price. But i saw some that said RFT/Siemens. Are these the same as the 80's siemens tubes? Because those used to be my standard for el34's. The only problem i have with NOS is the fear that they will soon be gone and i will again have to find something as good and won't be able to.
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:yes, i checked them out. Not too bad as far as price. But i saw some that said RFT/Siemens. Are these the same as the 80's siemens tubes? Because those used to be my standard for el34's. The only problem i have with NOS is the fear that they will soon be gone and i will again have to find something as good and won't be able to.
Hi, yes they are the same, they where made in gdr, that was east germany, and i think you are right marshall used to use them. they are good tubes. far better than anything made today.

Dukeamps
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

I've been using Electro harmonix EL34's. They sound quite similar actually. not as good, but a similar voice. At first i wasn't sure, but after using them a short time i couldn't go back to the winged C's, as the top end seemed indistinct and the lows muddy by comparison. It's been some time since i used the siemens, but i'd sure like to hear them next to the EH and see how close or far off my memory is.
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:I've been using Electro harmonix EL34's. They sound quite similar actually. not as good, but a similar voice. At first i wasn't sure, but after using them a short time i couldn't go back to the winged C's, as the top end seemed indistinct and the lows muddy by comparison. It's been some time since i used the siemens, but i'd sure like to hear them next to the EH and see how close or far off my memory is.
Hi, the eh are the same construction rft el34s, and they do sound similar, but the rft sound bigger, i have tried both. the winged c don't breakup as good, and i don't like the chinese.

Dukeamps
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

Actually, i never tried the newest chinese. But I just happened to find some older ones i think were the previous gen of chinese (B series i think) and i was surprised at how good they sounded ! But i have this problem where i don't like using great sounding tubes that i know i won't be able to get eventually. So i don't use them for fear that when they die i will have to start using a lesser tube. Sounds crazy i know, but i don't want to get used to a certain sound then have to go lower. And crazy as this might sound, those sounded better than anything new i have tried in the last few years !
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:Actually, i never tried the newest chinese. But I just happened to find some older ones i think were the previous gen of chinese (B series i think) and i was surprised at how good they sounded ! But i have this problem where i don't like using great sounding tubes that i know i won't be able to get eventually. So i don't use them for fear that when they die i will have to start using a lesser tube. Sounds crazy i know, but i don't want to get used to a certain sound then have to go lower. And crazy as this might sound, those sounded better than anything new i have tried in the last few years !
Hi, I think you will be ok with the eh :)

Dukeamps
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

It IS cork sniffing really, isn't it? :D
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:It IS cork sniffing really, isn't it? :D

I think you are probably right. :lol:

Dukeamps
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

just put an old pair of eh el34s i had lying around into the amp, and they sound really good. i had ordered a new pair of eh el34s not so long ago, but they were microphonic so i sent them back.

Dukeamps
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

How would you compare them to the RFT/Siemens?
dukeamps
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Re: jmp 50watt with magnetic components transformer set

Post by dukeamps »

iknowjohnny wrote:How would you compare them to the RFT/Siemens?
hard to say, they both sound something the same.
iknowjohnny
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Re: jmp 50watt with magnetic components transformer set

Post by iknowjohnny »

I guess my memory serves me well after all. I haven't used them for probably 15-20 years, yet the first time i tried the EH i felt they were very similar. What is then puzzling however is that the majority seem to praise the old siemens, yet it seems as tho most find the EH lousy ! Doesn't seem to jive does it?
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