What is a reasonably priced 12ax7?

[ctcpete]

Any recommendations on a good choice for my Fender amps (Blues Jr and old Twin). I've used Electro Harmonix, they seem ok to me but my experience is very limited.

Thank you.

[Mars Amp Repair]

Hello CTCPETE,
There are many choices and even amongst the ones that are supposed to be superb, you can still run into situations where you need to try a few, esp in the earlier higher gain stages to find one that is quiet.

I use the JJ brand tubes in my shop as they only cost about ~$7.00ea and for the most part are reliable. If you are just fitting one amp with tubes, you might want to purchase some tubes that have been pre-tested for microphonics. They will cost more, but will hopefully preclude the need to deal with noisy tubes right out of the box.

I haven't bought from Eurotubes, but hear that guy does a pretty good job of pretesting & burning tubes. Also a local guy to my Denver area is NBS Electronics 'Fat Willie' or 'Lord Valve' also does fairly extensive burning & testing for microphonics.

Still I find because I buy like 20ea 12AX7's at at time, I can always find a quiet tube for the higher gain positions.

Mesa Boogie also has pretty extensive testing. They now source their 12AX7's (as well as the 12AT7 variety) from JJ.

Any of these pretested tubes will cost you more. IE: pretested 12AX7 Mesa ~$17.00, Tungsol from Lord Valve ~$20.00.

JJ from Tubesandmore.com...~$7.00.

I'm certain you'll get many different opinions about this subject. Hope that helps some...glen

[Chuck H]

+1, and...

The Q was "What is a reasonably priced 12ax7?" Reasonable is relative. For example, I love the old RCA gray plate 12ax7's. I had the opportunity about 6 years ago to buy 12 NOS for $18.00 US ea. NOS is key, NEW OLD STOCK. And they indeed were. One was unusably noisy, one failed prematurely and of the remaining 10, 6 were absolutely non microphonic and the other 4 were still much less microphonic than, say, a Sovtek LPS type and still usable as first gain stage tubes. So with the two failures I paid an average of $25.00 per tube after shipping. To me that's a good price for such tubes. The same tube today goes between $60 and $80. And sadly I used my last one about a month ago. Which brings me to my next point...

Will I buy more of this same tube? Probably not. Too expensive. But, is $80 a reasonable price for that tube? Probably. It's a matter of supply and demand. They're no longer made.

I think your question was more about what you should expect to pay for a good quality tube, rarity and collectability aside, right? In which case I would default to Glen's advice. look at tube reviews to find the tonal character you're interested in and pay a little extra for burn in and microphonic testing. I have had many problems with new tubes out of the box so if you're buying single pieces for a retube you will likely save money by paying extra for these services. I know the old RCA tubes to be,on average, of excellent quality or I wouldn't have taken the chance on untested tubes. With new tubes my experience has been that untested tubes are either bad or fail prematurely not less than 30% of the time. And far fewer untested new tubes are non microphonic enough to be used as V1 in high gainers. The Sovtek WA and WC being exceptions, but they sound like crap. So pick a tube that you like the reviews on and pay extra for non microphonic and burn in. You'll save money and a lot of your own time in the end. Price varies with new tubes and sellers but I would expect between $20 and $35 for a tested, non microphonic V1. Low microphonics (as opposed to "non" microphonic) is fine for the other amp positions and should cost a little less.

Chuck

[olddawg]

If I was needing tubes for a shop I would probably stock EHs or JJs. For my personal amps it's NOS (usually RCAs, Sylvania, or Mullards) all of the way, I have 4 EHs in my hand right now. There is nothing wrong with them. I use them for test swapping. They are not microphonic. They just aren't as smooth and rich sounding as the NOS tubes. I know that these are funny words to use, but the difference is very obvious. If you are driving an amp and want to have thick harmonics and controled feedeback, it makes a big difference. If it's a big clean Fender it will be more glassy, meaty (another wierd term), and less grainy for lack of words. It's very subjective but even brand new amps sound sterile, and even brittle with the new tubes available to me. I'm constantly looking for old junk chassis to pull old tubes out of. Some are great, some are shot. IMHO if you are just tubing two amps, go NOS if you can. Remember, tubes are mechanical. If you are buying NOS from someone they may or may not be what you expect. You can expect to have a box full of tubes to pick from over time if the quest bug gets you. For just a couple of amps it won't be that expensive and hey you now have spares!

[Chuck H]

To add a note to OD's suggestion of NOS tubes... Avoid the GE tubes. They are usually not microphonic and they are very reliable, but they sound like Sovtek WA and WC 12ax7's. Bland and dull with low gain for a 12ax7 type.

Another note. The Sovtek LPS is an excellent sounding tube, but normally at least a little microphonic, and nearly always too microphonic for V1. Point being you can buy a couple of LPS for the "other" positions in your amp and shell out more $$$ for a NOS non microphonic tested 12ax7 for V1. I've been very happy doing this with my personal amps. But my tastes may be different from yours. So read reviews too before deciding.

JM2C

Chuck

[jrfrond]

A few points to add:

1) There are no REALLY good NEW tubes out there, and as was said, NOS is NOS, like the old untested parts grab bags you used to get out of the back of Pop'Tronics magazine.

2) There are no reasonably-priced tubes anymore, and prices are hiked several times a year. If you want good tubes, you have to pay

3) I won't use Chinese tubes, period. I don't care who rebrands and tests them.

4) Price is NOT a determining factor of how good a tube is. Both pricey and cheap can be crap, as well as golden.

In part, I am referring to the JJ 12AX7's mentioned here. Personally, I think they suck and sound metallic, plus they have been unreliable every time I tried them. I don't care if they are $7.00. I won't sell them to my customers, and if they want us to install them, they can purchase them themselves.

As a tangent, I won't purchase components based on price either. I will spend a bit more to get a reliable name brand cap or resistor, rather than (again) the bargain-basement stuff sold by many suppliers.

[ctcpete]

Thanks very much for the replies. I have a better understanding of what to look for and what to avoid.

Thanks again, Pete