Used tubes that "test good"

Joined: 29 Nov 2003 Posts: 393 Location: Lake Mary, Florida

Now that I have a tube amp, I'm searching to buy different power and preamp tubes to see if I like certain ones more than others. I've ordered some NOS 6V6GT and 12AX7 tubes, but will come across used tubes for sale that "test good" for a lot less money. Anyone have experience buying used tubes that "test good?" Does this usually mean that they work but will probably sound a lot worse? My guess is that it can run the gamut of "sounds just like new" to "sound awful," but wondering if anyone has personal experience with this subject. Also, is there some objective measure by which a tube is graded to be "good" or "bad?"

Posted: Wed Jan 07, 2004 10:21 am

joe i know you can find a WIDE variety of used tubes including vintage ones at guitar shows but to the rest of your qs i got no clue man

Rich

Joined: 29 Nov 2003 Posts: 5324

ragnut wrote:

Now that I have a tube amp, I'm searching to buy different power and preamp tubes to see if I like certain ones more than others. I've ordered some NOS 6V6GT and 12AX7 tubes, but will come across used tubes for sale that "test good" for a lot less money. Anyone have experience buying used tubes that "test good?" Does this usually mean that they work but will probably sound a lot worse? My guess is that it can run the gamut of "sounds just like new" to "sound awful," but wondering if anyone has personal experience with this subject. Also, is there some objective measure by which a tube is graded to be "good" or "bad?"

some tubes will test out "Good" but depending on the tester (hardware and human), the tube *may* not have a very long "serviceable" life..

as for "tone", it's all subjective.. seriously subjective.. stick with NOS from a reputable dealer with a good return policy..

most of the "NOS" stuff at guitar shows are pulled from working/nonworking amps, and very rarely will the seller have a tube tester to show that individual tubes actual measurement.. sure some of the tubes _could_ be great tubes, but as soon as you stick a bad tube in your amp, and that 20.00 tube costs you 150.00 at your amp tech, you'll stick to Dealer-NOS tubes..

you could buy yourself a tube tester, and learn to test out tubes.. (this is a really good thing to learn to do, as to keep your dealers honest and to have the best quality tubes in your amp..)

look for a copy of the 1975 RCA tube manual.. (it has every guitar tube in it..) i bought mine about 6 years ago for $35.00..

in reality, you should not have to change out your tubes for 1000's of hours.. (depending on your amp's bias..) tubes take alot more abuse than one would think..

change them if you don't like the tone.. but properly bias your amp to the tube!! it's amazing how a couple of resistors can make your amp sound like crap..

Joined: 01 Dec 2003 Posts: 456 Location: Austin, Texas

throbgod13 wrote:

ragnut wrote:

Now that I have a tube amp, I'm searching to buy different power and preamp tubes to see if I like certain ones more than others. I've ordered some NOS 6V6GT and 12AX7 tubes, but will come across used tubes for sale that "test good" for a lot less money. Anyone have experience buying used tubes that "test good?" Does this usually mean that they work but will probably sound a lot worse? My guess is that it can run the gamut of "sounds just like new" to "sound awful," but wondering if anyone has personal experience with this subject. Also, is there some objective measure by which a tube is graded to be "good" or "bad?"

in reality, you should not have to change out your tubes for 1000's of hours.. (depending on your amp's bias..)

Joe, this is an accurate statement. Although I know you were asking about different tube sounds, if you like what's in your amp, leave them in there and then practice your playing rather than messing around with tubes. I bought my first Marshall 100-watt stack in 1983. I just sold it 2 years ago. In all that time, I never had to change any tubes, and the amp sounded fine. It was used the entire time I played live, and at 100's of rehearsals. I know I've said this before, and a lot of people love to argue this, but unless you have an Eric Johnson type ear, the differences are not extremely noticeable. I find that good playing skills will consistently outweigh any minor tone differences you might find by changing tubes. Then again, some people like to mess with stuff for fun. You just have to decide which category you fall into.
Dana <~~~

Joined: 29 Nov 2003 Posts: 393 Location: Lake Mary, Florida

Dana, I'm looking to "get my feet wet." I've heard so much about tinkering with tubes and changing out speakers to improve sound, I thought I'd give it a try. The Fender Vibrochamp only cost me $200+, and I only need one power tube in it. Soon I'll be getting 3 different power tubes, a diff preamp tube, rectifier tube, and Weber speaker. It's fun for me. Within the past few months I bought a bunch of different pedals. Some I love, some I don't see much good in. And everything I tinker with, my son tinkers with too. Thanks for your input. --Joe