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My tube rolling experiences with Type 45 tubes

rjw1678

rjw1678

Active Member
I have had my Dennis Had Inspire 45 FireBottle amp for about a week. I am trying different Type 45 tubes it. They are -

Philco Type 45 Globe shape with 5Z3 rectifier - came with amp
RCA Radiotron Type 45 Globe shape with 5Z3 rectifier
Raytheon Type 45 ST coke bottle shape with Type 80 rectifier - came with amp
Sophia Electric Type 45 mesh plate globe shape with 5Z3 rectifier

The Philco tubes and the RCA tubes sound very similar and they have a lush tube sound very musical - sounds very nice to me. The Raytheon tubes have a more accurate sound, not as much of the lush tube sound - they sound good with vintage rock music. The Sophia Electric tubes seem to be a good compromise between the "Philco & RCA" tubes and the Raytheon tubes, they have more of the lush tube sound without giving up the accuracy of the Raytheon - I think the Sophia's will make a nice daily listening tube.
 
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Interesting, as my recent trip through my 45 stash pretty much matches your findings. The Raytheons are nicely balanced and seem to do everything just right, but are missing a little of that flesh-and-blood mid-range presence the RCA globes have in spades.

For current production I settled in to the TJ mesh (might be an older relative of the Sophia?) which has a big, bass-y sound that is really nice as a daily driver across many musical styles but again, nowhere near the mid range magic of the RCA globe that is really something special in this regard.

If I want to really experience some in-the-room vocals and taste the space and emotion of the recording environment, say Neil Young's Massey hall or Carmen Mcrae's Live at Birdland, I put in those RCAs and get completely lost. I guess I'd have to say they are my favorites because they do SO well at illusion.

I often wish I had the speakers to satisfy me with 1.5w 45s but for me, 100db sensitivity is not enough and 2A3 is much more like it. Not that I'm complaining, I LOVE 2A3s but 45s just might be the best sounding tubes I've tried to date.
 
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Philco never made their own tubes, so it would be interesting to know who did make yours. Wouldn't be remotely surprised if it was Sylvania, but it may have been RCA. I believe all this was pre-EIA codes so unless you happen to recognize the construction I doubt there would be anything to tell you where it came from.
 
Billfort said:
Interesting, as my recent trip through my 45 stash pretty much matches your findings. The Raytheons are nicely balanced and seem to do everything just right, but are missing a little of that flesh-and-blood mid-range presence the RCA globes have in spades.

For current production I settled in to the TJ mesh (might be an older relative of the Sophia?) which has a big, bass-y sound that is really nice as a daily driver across many musical styles but again, nowhere near the mid range magic of the RCA globe that is really something special in this regard.

I often wish I had the speakers to satisfy me with 1.5w 45s but for me, 100db sensitivity is not enough and 2A3 is much more like it. Not that I'm complaining, I LOVE 2A3s but 45s just might be the best sounding tubes I've tried to date.
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Ever try the 71A?
 
No Jay, heard great things about them but even less power than the 45 right?

Actually, one directly heated triode that impressed the hell out of me was the 50 - maybe even up there with the 45 - but rare as hell, a little tricky to drive (I'm told) and for those reasons, beyond my wallet and technical abilities. Sure loved the amp my friend built around them though.
 
Billfort said:
No Jay, heard great things about them but even less power than the 45 right?

Actually, one directly heated triode that impressed the hell out of me was the 50 - maybe even up there with the 45 - but rare as hell, a little tricky to drive (I'm told) and for those reasons, beyond my wallet and technical abilities. Sure loved the amp my friend built around them though.
Click to expand...

Maybe just under a watt, you'd want horns for sure.
 
Funny you should mention the 71A. Once i finish pulling my hair out over this phono pre amp, a 27/56 driven 71A amp is the next project. Gonna use a 4 pin socket for the rectifier and choose between a 80/5Z3. Won't get real loud, but might be just the thing for the 604s or the Simplexes. I have also heard it's even sweeter than the 45...
 
71A's are fairly inexpensive too, at least in the vintage DHT world. I sort of wonder what parallel 71A's would do. That should get you close to 45 power levels.
 
I put the Sophia type 45's back in the amp this morning. I feel that the RCA globe type 45's and the Philco globe type 45's are truly special and I am saving them for special listening occasions, I don't want them to wear out on daily listening.
 
Billfort said:
For current production I settled in to the TJ mesh (might be an older relative of the Sophia?) which has a big, bass-y sound that is really nice as a daily driver across many musical styles but again, nowhere near the mid range magic of the RCA globe that is really something special in this regard.
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good eye!

tj music closed down. sophia rebranded and sold leftover tj full music tubes, as
did the tube store under their “northern electric” label. not sure what the rest
of the story
is. SE still have some left.

even 10 years late, i enjoyed reading the shootout. thank you for documenting this experience.
 
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