2a3 options?

Mr. Bissness

Mr. Bissness

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What are some nice alternatives to NOS 2a3 tubes? I have a pair of mono blocks and would like to try another set of tubes. I have the EH currently but they have 15years of use on them. I need to get them tested but thought I would also see what are some other preferred options. Thanks
501A188A-E2A9-4E21-BA6D-8C655E240F41.jpeg168CB910-DD08-400D-AEE8-C9002E019D85.jpeg
 
Those Sovteks aren't too shabby as cheap 2A3s go, but I packed 'em away as "test tubes" years ago after plugging my first pair of genuine RCAs into my build. As an alternative to NOS tubes you might consider plain ol' "OS" tubes. Ditch the "New" for great testing used tubes and save a bundle!

RCAs are very nice but I also liked Sylvanias and GEs and Tung Sols and... well, it's hard not to like a 2A3! :)

I like the look of your Moondogs! It's been a long time since I looked closely at that design, but the layout is sure pretty.
 
A few I've enjoyed... BTW I just dropped a matched pair of NOS TungSol's on a tile floor last month and felt a little sick after that.
The NOS vintage stuff can be great but the prices have went through the roof (and getting some mono plates? Good luck) so I'll leave that up to you and what you want to spend . I think RCA and Sylvania pretty much produced most of the old 2a's and there are all the others like TungSol, Ken Rad, Ratheon, etc... then here's a few links. The JJ's are worth a try for sure.
Some vintage examples to look for: Tube of the Month : The 2A3
www.tubedepot.com

JJ 2A3 - 40 Watt Power Vacuum Tube

These JJ 2A3 - 40 Watt Power Vacuum Tubes are quite possibly the most sturdy modern triodes ever! This tube boasts a 40 watts plate dissipation rating.
www.tubedepot.com www.tubedepot.com


wooaudio.com

Psvane ACME 2A3 Tube — Woo Audio

Special order, ships in 1–2 weeks Select matched pair or matched quad Have questions? Contact us
wooaudio.com wooaudio.com
 
Last edited:
Redboy said:
Those Sovteks aren't too shabby as cheap 2A3s go, but I packed 'em away as "test tubes" years ago after plugging my first pair of genuine RCAs into my build. As an alternative to NOS tubes you might consider plain ol' "OS" tubes. Ditch the "New" for great testing used tubes and save a bundle!

RCAs are very nice but I also liked Sylvanias and GEs and Tung Sols and... well, it's hard not to like a 2A3! :)

I like the look of your Moondogs! It's been a long time since I looked closely at that design, but the layout is sure pretty.
Click to expand...
I agree and couldn't have said it better! 👏
 
RPMac said:
JJ 2A3-40 is a nice affordable new manufacture tube. EML tubes are more expensive, but I have no experience with them. Then there are a lot of Chinese tubes. Like Redboy, I have several OS tubes that I play most of the time along with the JJ.
Click to expand...
I really dig those JJ 2a3-40 tubes. The sound as good as the EMLs IMHO. Rugged as well!
 
If you got 15 years out of the EH 2A3s, I would buy another pair!

I have experienced more failures (by number, not percentage) with JJ 2A3-40s than EH/Sovtek 2A3s, and I have used a gazillion EH/Sovtek 2A3s.
 
I was leaning towards the JJs as well. The couple photos I found online seem to also have more of the Tube Glow vs these EH... some times I have to double check that they are even turned on.
 
paulbottlehead said:
If you got 15 years out of the EH 2A3s, I would buy another pair!

I have experienced more failures (by number, not percentage) with JJ 2A3-40s than EH/Sovtek 2A3s, and I have used a gazillion EH/Sovtek 2A3s.
Click to expand...
Hi Paul, I’ve had my JJ’s running on paramounts for a good bit with no issues. Is your experience recent? I did read that JJ had issues a few years back. @marantzfan has had a set of JJ’s for longer than I have.
 
Sounds like I need to start a WTB add and see what’s available. Thanks for all the good information!
 
These things (which can be, I believed, labeled with different brand names) are rather silly looking -- but they sound quite good.
These are labeled "Sofia". I think (??) it is essentially a 300B with a 2.5V filament. The "mesh" plates are perforated metal -- they're rather garishly showy, but not without their audible charms.

DSC_4280 (2) by Mark Hardy, on Flickr
DSC_0263 by Mark Hardy, on Flickr

They're not particularly easy, nor cheap, to find, though (AFAIK).



I keep meaning to acquire a pair of the JJs to compare.
 
gegge said:
Around 2015, many owners of Bottlehead amps had problems with the JJ 2A3-40 tubes in their amplifiers with lots of failures and JJ even refused to let the warranty apply to tubes used in Bottlehead amps for a while (you can read about this on Bottlehead forum) this was cleared up eventually if I belive, is it these failures you are referring to when it comes to JJ 2A3-40 tubes?
Click to expand...
I thought it was about the EML mesh plates in the direct coupled amps...Paraglow and early Paramount...with an arcing problem. This led to the “soft start kit”.

I have JJ 2A3-40 in my Paraglow now.
 
The really early Paramount amplifiers in the 2A3 configuration had arcing problems with EML tubes (oddly enough you could put a $35 pair of Chinese tubes in there or Sovteks without any problems), so we redesigned that circuit to have different startup behavior which solved that problem entirely. It's actually been a really long time since I've even seen a 2A3 Paramount with the soft start feature added. I do not recall their being any issue with Paraglows since they supply the driver plate voltage from the 2A3 cathode bias resistor, which is another way to avoid this issue when building a directly coupled 2A3 amp.

There was at least one issue with 2A3-40s dying in a Stereomour, but in a cap coupled AC heated 2A3 amp that runs the tubes by the numbers, it gets really tough to blame the amp manufacturer...
 
I had those same tubes as well as a pair of the EML meshies. The Sophias looked spectacular but only lasted for a short time as did their replacements. The 2.5V filaments are vey dim even within the mesh plates.
 
The Paraglow problem was with John Tucker‘s Paraglow II kit installed, not the original Bottlehead design.
I have rewired mine so the driver plate voltage comes from the 2A3 cathode through a resistor and choke instead of the CCS.
 
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