New production 12ax7 impressions

slegros

Member
Messages
498
Apologies in advance for the long post, but I hope some of the info is useful! Just my observations FWIW...

I recently was swapping some popular current production 12ax7s around in several amps again, and thought I'd share my impressions of 3 of my favourites.

Tung-Sol 12ax7, and Mullard:

To me these are somewhat similar in that they seem to be the basic New Sensor Russian made tubes given a similar additional treatment. I'm not sure what New Sensor does here, but when I first tested the Tung-Sol 12AX7 several years ago it had noticeably better detail, and clarity over similar NS short plate tubes like the standard Sovtek 12ax7 and EH branded tubes. With the Mullard it seems they gave this same treatment to their long plate design. Both to me have better clarity, and detail when compared to other offerings from NS without being harsh. I really like both of these tubes clean, and if buying New Sensor tubes, these are the 2 I would pick. The Tung-Sols DO NOT like being in the cathode follower stage of Marshalls in my experience!!

Is the Mullard a true reissue? Not even close...:
http://www.marshallforum.com/marsha...-reissue-vs-original-physical-comparison.html

But what the new Mullard is to me, is NS's best long plate design, and a decent tube in its own right.

Where the Mullard and Tung-Sol differ to me is in the EQ balance. The Tung-Sol seems to accentuate the high and lows more while the Mullard seems to have a very flat EQ. I like the Mullards in amps where I want a preamp tube with good detail that wont colour the amp, but will just bring out what's there. With the Tung-Sol I like them in darker amps that I want to brighten up a bit, or where I'm looking for chimey cleans.

JJ ECC83S:

I like these… Recently I have seen a lot of people with less than a stellar impression of the JJ. Sure they are inexpensive, and have a distinct character, but to me they are a great tube. One thought comes to mind: Using the right tool for the job.

The JJs to me seem to accentuate the mids, and as a result in some amps they can sound muddy to me, and lacking in detail. In most amps I don't like them clean, but I do like them in amps that I find overly bright. I recently used them in a Blues Junior 3 with the so called 'sparkle mod'. Compared the the stock GT Sovtek 12ax7s the JJs were much warmer, fuller and took out a lot of the high-end harshness that the Sovteks had. I also tested a Mullard and Tung-Sol in the same amp, and the detail that these 2 tubes had came across a bit harsh in the Blues Junior. Hands down myself and 2 guitarist friends liked the JJs best in the BJ3… I also like the way they overdrive. The mids seem to bring on a nice creamy overdrive. Again for some this may not be the sound you want… But I can see them working really well in a JCM800 or in amps where you want to darken the overdrive a bit. One interesting observation I had was that between a Mullard and a JJ the difference was a little bit like the tonal difference I recently noticed between a G12M25 Greenback(Mullard), and a g12-65(JJ) with the larger dust cap….

A few resources I found interesting:

12AX7 Reviews:

http://www.thetubestore.com/Resources/Product-Reviews/12AX7-Tube-Review

http://www.amplifiedparts.com/tech_corner/12ax7_comparison_of_current_made_tubes

With regards to these I find the Tube Store reviews to be more in line with my own findings. I disagree somewhat with both reviews of the JJ. Tube Store reviews them as being a bit noisy, and more prone to microphonics than the Tung-Sol or Mullard. I have found them to be just as quiet, and no worse for microphonics.

Amplified Parts shows the Mullard as being the highest gain, with the Tung-Sol the quietest, and the JJ being somewhat low gain… I have found all 3 to have similar noise levels, and decent gain. Perhaps the Tung-Sol is highest gain of the 3, but its a bit hard to quantify as all 3 overdive a bit differently. The TS accentuates the highs and lows a bit more it has a bit more scooped, articulate overdrive, the Mullard flatter, and the JJ a bit rounder to me, but it also depends on the amp they are used in..

I've had good reliability from all 3...

Strange, or perhaps not so much, that in both cases above the higher priced tubes seem to get the better reviews….

I also found this blog interesting:

http://la-economy.blogspot.jp/2013/05/current-production-12ax7-tubes-ten-of.html

The author makes a good point regarding buying from vendors you trust, and highlights the wide variances in the production tolerances of modern tubes. Also shows 40yr old tubes testing almost dead on spec! LOL!!

That said, despite the wide production variances in modern production tubes, I have found their sonic characters to be fairly consistent… I.E. a Tung-Sol will sound like a Tung-Sol no matter how it tests electrically…
 
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dbun

Member
Messages
844
I'm really liking the Tung-Sol in my Hayseed 30.

Have you tried the JJECC803s? This is another modern tube that is highly regarded. Many people don't like the JJ ECC83s but find the ECC803s quite good
 

slegros

Member
Messages
498
I'm really liking the Tung-Sol in my Hayseed 30.

Have you tried the JJECC803s? This is another modern tube that is highly regarded. Many people don't like the JJ ECC83s but find the ECC803s quite good
No! Its one of the few new production tubes I haven't tried!

I guess I was a bit put off by some of the warnings against microphonics in high gain amps and combos with these given by several tube vendors. Not an issue with other nice sounding tubes, so I just used other tubes…

Another I'd like to try is the Tung-Sol ECC803s!
 

dazco

Member
Messages
15,048
I've tried the 803 and i like it a lot more than the 82. But neither IMO comes close to my fav new prod AX7 which has been discussed in this thread, the tung sol RI. I have gone back and fourth with those, the 803, 82, EH, sovtek LPS and WA/WB, old 80's chinese (my fav ever till now, tho still like them) the russian mullard RI and several others. The amp is a homebrew JCM 800 sort of affair basically, but with a lot of differences and more gain in the pre. I've watched the different tubes each sound better and worse as the amp has gone thru uncountable changes in my search for the grail. The mullards i was liking a lot for a while, but in the amp's current state they don't sound good at all. This all just goes to show how circuit dependant they are and how no tube is going to be great in ever amp. But the one thing i kept coming back to after several years of swapping tubes if the tung sol RI. Once i had enough listening time under my belt to know them all like the back of my hand, the tung sols gradually showed me they were to my ear the best no matter what config the amp's state was in. They just have the sweetest top and and best clarity. I still use a chinese in the stage 3/cathode follower slot because the TS's won't tolerate that cathode voltage, which is the same for the mullard and LPS. But i might even keep a chinese there even if that weren't the case because i think it may be a good balance like this.

Anyways, big vote here for the TS as best current 12AX7.
 






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