2A3 tube review

[tomchaoda]

I just made my first tube of a SE 2A3 amp. I am currently using the Sovtek 2A3 tubes. As all know that one of the fun in tube amp is that one can always switch different tube to get different sound quality. For 300B, I can find many tubes review articles and comparison. However, I can not find any tube review regarding different vendor of 2A3 tubes. Maybe there isn't that many 2A3 tube brands made as compare to 300B. I can find the EH 2A3 Gold tube, the Sovtek tube (I am using this one) and the Valve Art 2A3 tube. I can't seems to find any other than these 3 brands.

I am wondering if anyone have done their own comparison? If you do, can you compare these tubes (from your view point is fine)?

Thanks,

Thomas

 

[audiousername]

The Sovtek is fine. Don't lose sleep over it just because it's one of the cheapest. Rugged too. Some people here (I think it was Frank) have run these 50% or so above ratings for years without damage. Don't forget that the choice of operating point for the driver valve and output valve can change the sound too! And a couple of resistors are cheaper than a new output valve.

On other makes of 2A3, I don't have experience with them so I can't comment on the sound differences. I believe the Valve Art is a bi-plate (consisting of two valves internally connected in parallel) like the later makes of 2A3 while the others are mono-plates like the original early '30's version. If you're still interested in more exotic brands, AVVT, KR and JJ/Tesla (from the Czech Republic) and TJ/Full Music (China) also make 2A3s or variants thereof.

EDIT: I just remembered another thread where you were asking questions about the PS and a 100uF input cap. With the thermionic rectifier, it should be smaller, or you'll be looking for new 5U4s instead of 2A3s Just a reminder.

 

[tomchaoda]

audiousername:

In my previous psu section, I added one 2.2uF/630v cap and it seems keep the voltage in check, even though it is not what I have simulated in PSU Designer II! But, so far, it seems running fine (2 hours time). The things that still bother me a little bit is that the resistors (I am using CRCRCR) is hot at 76C and I still have a little bit AC current sound (104mv), which I am quite sensitive with! However, the sound is very good. My next step is to replace the first R into a 10H choke to see how it goes, in terms of the AC current sound?

So far, I am very satisfied with Sovtek's sound.

Thanks,

Thomas

 

[EZ_Angus]

I've heard three types of 2A3 tubes in my bottlehead paramour amps. (1) the stock Valve Arts. I found these very lush and romantic. overly so really, often descending into mushy and kind of bloated. (2) the sovteks. these to me were the polar opposites of the VA's, in that they were very etched and hard-sounding. if the recording is dry, these can be painful to listen to. (3) TJ full music meshplates. These tubes are WAY more expensive than either (1) or (2) but to me, well worth it. they strike a great balance between romance and detail. They have a full, lush, balanced sound that retains a good amount of detail and are never harsh.

If I couldn't swing the TJ's, I'd actually take the valve arts over the sovteks.

as always this is from my ears, my system, my room. YMMV, WTFDIK and TINSTAAFL!!

Kevin

 

[tomchaoda]

EZ_Angus: Thanks for the info.

I am just wondering anyone have tried the Electro-Harmonix Gold 2A3 tube?

I seems not able to find the TJ/Full Music 2A3 in the US! Can anyone tell where can I find it in US?

Thomas

 

[EZ_Angus]

Hi. Bottlehead sells them in the US. go to this page

http://www.bottlehead.com/et/parts/parts.htm

and scroll down to near the bottom. I bought mine from diyhifisupply in Hong Kong.

 

[mcs]

(2) the sovteks. these to me were the polar opposites of the VA's, in that they were very etched and hard-sounding. if the recording is dry, these can be painful to listen to.

How long time did you use the Sovteks? Mine started out like you describe, but they got a lot better after a couple of months.

Best regards,

Mikkel C. Simonsen

 

[EZ_Angus]

Hi Mikkel: interesting observation. I only lasted a week with the sovteks. maybe I should have been more patient. In any event, I am a TJ devotee now! best KEvin

 

[audiousername]

The things that still bother me a little bit is that the resistors (I am using CRCRCR) is hot at 76C and I still have a little bit AC current sound (104mv), which I am quite sensitive with! However, the sound is very good. My next step is to replace the first R into a 10H choke to see how it goes, in terms of the AC current sound?

The choke will do a great job in reducing hum. Also, apart from reducing hum, the choke may also change the sound of the amp: it's probably something you should try to see if the changes are for the better or worse - to your ears.

On the issue of hot resistors, parallel higher value resistors or series smaller ones to decrease the dissipation from each resistor if it bothers you.

So far, I am very satisfied with Sovtek's sound.

Good to hear! Lots of other people are too.