just swapped out the 2A3's from my Fi2A3 amp for Sophia 45's.
They shouldn't even sound this good with the not so efficient speakers i'm using, or for that matter in the Fi which isn't ideally built for 45's but they do????
Maybe this is the natural progression? I began with 300b's, didn't care for the heat in summer so tried the 2A3 for a few years and now... seems there's no going back. Hello my name is and i'm a triodeoholic...
So what you guys suggest i do next, use the amp the way it is or swap out the DS-025 opt's for DS-050's and change a cap as Don G did for a customer on request? 6moons audio reviews: Fi 45 Stereo "Prototype"
They shouldn't even sound this good with the not so efficient speakers i'm using, or for that matter in the Fi which isn't ideally built for 45's but they do????
Maybe this is the natural progression? I began with 300b's, didn't care for the heat in summer so tried the 2A3 for a few years and now... seems there's no going back. Hello my name is and i'm a triodeoholic...
So what you guys suggest i do next, use the amp the way it is or swap out the DS-025 opt's for DS-050's and change a cap as Don G did for a customer on request? 6moons audio reviews: Fi 45 Stereo "Prototype"
I'd swap in the right transformer for the 45 first off, and make sure that the tubes are operating within their dissipation ratings.
I've always preferred the 45 to the 2A3 - not really sure why exactly. I run 300B year round despite the heat because of my power requirements. (My amps have vacuum tube based regulators and make a lot of extra heat.)
I've always preferred the 45 to the 2A3 - not really sure why exactly. I run 300B year round despite the heat because of my power requirements. (My amps have vacuum tube based regulators and make a lot of extra heat.)
The Sophia 45's are sounding more like live music then the RCA 2A3, JJ 2A3-40 and Shuguang Treasure 2A3-Z tubes i have. It's like there's more layering plus the mids are richer. More like the 300B mids only without stopping there.
I guess i'll have to talk with Don G about the iron and cap changes vs as is. His Fi2A3 amps are supposed to be switchable for either tube by changing the operating point via choice of rectifier tube. Prob will end up saving for new iron.
In the meantime i want to finish Wooden Design Victor/166es-r speakers i started. What amazes me is that i hooked up a old pair of ~89db EPI 100 speakers i use/the HDTV for the sake of making sure the new tubes would be good in actual use vs testing only to find the 1.5watt output sounds great with them. Didn't care for the EPI's with the 2A3's at all.
I guess i'll have to talk with Don G about the iron and cap changes vs as is. His Fi2A3 amps are supposed to be switchable for either tube by changing the operating point via choice of rectifier tube. Prob will end up saving for new iron.
In the meantime i want to finish Wooden Design Victor/166es-r speakers i started. What amazes me is that i hooked up a old pair of ~89db EPI 100 speakers i use/the HDTV for the sake of making sure the new tubes would be good in actual use vs testing only to find the 1.5watt output sounds great with them. Didn't care for the EPI's with the 2A3's at all.
Anyone in the NYC area that will allow an audition of an amp using 45, 2A3, or 300b tubes? I don't currently have the funds to build an amp using these tubes and would like to hear an amp using them. Of course it is purely subjective unless I can bring my own loudspeakers for a valid evaluation.
Scott
Scott
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In my less than humble view, the 45 will always win when compared against the typical dual-plate 2A3 triode... as it's really two triodes in parallel which never quite sound the same as a single triode.
I'm not a fan of the RCA dual-plate 2A3 at all... if you want the better dual-plate 2A3, get Sylvania. Same with the 45, i.e., Sylvania over RCA. I can't comment on the Sophia 45 as all of mine are NOS of various brands. I do have a pair of Emission Labs 45s... these are huge bottles and in my view are NOT a 45... but something made to be close to a 45 spec for plate curves and filament requirements. I find them to not sound like a real 45 and to be very sensitive to mechanical excitation... even a hand-clap near them sets them off. You also need to run them ~40ma before they sound their best.
Regards, KM
I'm not a fan of the RCA dual-plate 2A3 at all... if you want the better dual-plate 2A3, get Sylvania. Same with the 45, i.e., Sylvania over RCA. I can't comment on the Sophia 45 as all of mine are NOS of various brands. I do have a pair of Emission Labs 45s... these are huge bottles and in my view are NOT a 45... but something made to be close to a 45 spec for plate curves and filament requirements. I find them to not sound like a real 45 and to be very sensitive to mechanical excitation... even a hand-clap near them sets them off. You also need to run them ~40ma before they sound their best.
Regards, KM
Hey thanks! Here's an idea for you. Why don't you buy at least 10 of the kits I currently have for sale to fund that project?
Good Question! 2 reasons:
a) I am currently building my own SE
b) You do not ship to Greece
Seriously though, you cold make such a kit and write off the expense as "research"
My suspicion is some of this is down to interaction between the source impedance of the amp and the speaker.. The 45 has roughly 2.5X higher plate resistance than the 2A3 which means that the amplifier source impedance is also increased by a similar amount, that would account for part of it..
I doubt into a 2.5K load you are getting much over 1W with the 45, my design into 4K is just making 1.6W, and with a 5K transformer 2W..
Still it works and sounds good to you, and that is the point. You may find exactly the reverse results with another speaker.
I use older JJ 300B and have found them to be within a stone's throw of well used vintage WE 300B in my amplifiers, and almost indistinguishable from early 21st century WE production. (Listening tests were fairly casual. No measurable difference in amplifier performance.) So I am a bit surprised that the 2A3-40 which is essentially the 300B with 2.5V filaments did not fair better.
Interesting. Not that it's the same tube, but I seem to prefer a single triode section of 6AS7 contra both in parallel, up until more power is needed of course. There seems to be something messing things up just a wee bit when several devices try to cooperate.
Well, you have two devices which basically can't be a perfect match between them.... so you will always have some non-linear result when in parallel vs a single device. This is the rub with the dual-section 2A3... you would likely notice the same if you run a pair of 45s in parallel, regardless of how well the pair are matched. Yes, you can double the power, but the linearity/purity of a single 45 is no longer there.
Regards, KM
Haven't heard the Sylvanias but I've been a happy engraved base RCA Cunningham 45 user for a long time. Sylvania 5965s driving those RCAs, tho'; that's a little slice of heaven.
I have heard the EML Solid, didn't sound good at all even in a Yamamoto A-08 that was supposedly designed for it..
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