In need of some new tubes

[csadams5]

I recently got a used Mesa Boogie Roadster and it looks like I am in need of a new set of tubes (two power tubes are glowing blue and the volume drops out and fizzes). Where are you getting your tubes from? I found a few places that sell full retube kits and that is the way I am leaning. I figure for a used amp itis cheap insurance. Thanks in advance.

Chris

[tazzboy]

http://www.eurotubes.com/index.htm

[BiggerJohn]

I thought you were required to use Mesa labeled tubes in Mesa amps or else the warranty is void.

[Green Lantern]

Usually, I buy used old stock tubes from eBay.

[BobbyZ]

The only tubes that need to be matched are the power tubes. You can mix things up with the preamp tubes if you want.
With a Mesa(since thay don't have a bias pot) you want to buy power tubes that are in the right bias range for a Mesa. I believe most tube sellers can do that for you. Or you can just buy them from Mesa.
Mesa doesn't make tubes thay just put MESA on them like TAD, Groove Tubes and a few others.

[uriah1]

Mesa imports russian and chinese tubes and rebrands. Anything you to do
to up that offering would help.

[Tarnisher]

+1 on eurotubes. Good people. Bob had me over to his house when I lived in Portland. I told him what I wanted my amp to sound like, and he had me setup and play while he swapped tubes until we got it right.

[jh45gun]

The tubes glowing Blue does not necessarily mean they are bad though they could be:

C. Blue Glow -- what causes it?

Glass tubes have visible glow inside them. Most audio types use oxide-coated cathodes, which glow a cheery warm orange color. And thoriated-filament tubes, such as the SV811 and SV572 triodes, show both a white-hot glow from their filaments and (in some amplifiers) a slight orange glow from their plates. All of these are normal effects. Some newcomers to the tube-audio world have also noticed that some of their tubes emit a bluish-colored glow. There are TWO causes for this glow in audio power tubes; one of them is normal and harmless, the other occurs only in a bad audio tube.

1) Most Svetlana glass power tubes show FLUORESCENCE GLOW. This is a very deep blue color. It can appear wherever the electrons from the cathode can strike a solid object. It is caused by minor impurities, such as cobalt, in the object. The fast-moving electrons strike the impurity molecules, excite them, and produce photons of light of a characteristic color. This is usually observed on the interior of the plate, on the surface of the mica spacers, or on the inside of the glass envelope. THIS GLOW IS HARMLESS. It is normal and does not indicate a tube failure. Enjoy it. Many people feel it improves the appearance of the tube while in operation.
2) Occasionally a tube will develop a small leak. When air gets into the tube, AND when the high plate voltage is applied, the air molecules can ionize. The glow of ionized air is quite different from the fluorescence glow above--ionized air is a strong purple color, almost pink. This color usually appears INSIDE the plate of the tube (though not always). It does not cling to surfaces, like fluorescence, but appears in the spaces BETWEEN elements. A tube showing this glow should be replaced right away, since the gas can cause the plate current to run away and (possibly) damage the amplifier.

[gadgetfreak]

I own a mesa express 5 50 and it's wonderful. I have retubed many times. You have to have Mesa branded tubes in the amp if you need service work done but other than that you can just ask your tube dealer to give you the correct power tubes.

I deal with Doug @ Dougstubes and he knows exactly what to do and I have never had an issue with him that he didn't or couldn't fix.

If you are hung up on using Mesa's get the spxa7's, there a little more but much better 12ax7's than regular ones. Btw Mesa is using Checz and russian tubes right now, Haven't seen any chinese in a long time.

I literally had a night and day experience getting rid of the chinese tubes in my mesa and used tungsol,JJ,sovtek Lps and shuangang chinese for V3, but our amps are different and you may want to just call or email whoever you pick and let them know what you have and what sound your going for

Good luck and remember no bias'ing required on the Mesa's, plug and play

[marshman]

The presence of Mesa tubes is, as noted, only inportant for warranty work. If your amp is used and old enough to require new tubes, I'm guessing that warranty isn't all that important. If the tubes in the amp are Mesa, just hang on to them in case you ever have to deal with Mesa. If you're prepared to splurge, I think Mesa still has Siemens EL34s in matched pairs available for purchase.

I've bought very few new tubes in my day and have been very happy with the JJs I've bought--EL34s, 6L6GCs, EL84s and 12AX7s, but I've never actually played through anything with NOS Mullard EL34s or RCA 6L6GCs, and to be fair, I've thought the sovteks that came in most of the amps I've owned sounded fine, as well.

As you said, a good set of known good tubes is always a good idea for a tube amp, but maybe you could find a good 12AX7 to try out in all the preamp positions and one good pair of power tubes and determine if it's actually your tubes that are the problem. If you don't have to rush for the replacement tubes, you might be able to bide your time and find a good deal on something you think you want instead of settling for whatever's cheap and fast.

[csadams5]

Since the amp is used, I am not concerned with using mesa tubes. I did find a set on analogtube.com from JJ that I am thinking about. I have never heard of the site before and was also looking for other suggestions. Thanks for the info. I will keep you updated.

Chris

[guitar1amp2000]

I see you are in the DFW area. Call Jim at JMI Music. He's in Ft Worth. 817-284-5877.

[csadams5]

I will give him a call. I always prefer to shop local if possible.