[jopagi]

I've recently purchased my first tube headphone amp -- a SinglePower PPX3 with slam. Being brand new to the whole tube world, I'm finding myself lost in the forest a bit... (but what an interesting place to get lost in!)

A few pointers would be helpful. I've looked through the tube FAQ and didn't see what I was looking for.

I can easily look up the 5687 tube and find equivalent or near-equivalent tubes.

But how do I know which tubes produce which sound characteristics? If I'm looking for a brighter top end, or more air, or warmer midrange, etc. are there websites with this info? Do I look for certain tube specs?
Are the sound characteristics of a particular tube different from amp to amp?

And once I get some new tubes, are there any preferred techniques for A/B testing? Of course, I don't have two identical rigs that I can compare. Listening to one tube, powering down the amp, letting it cool down, then replacing the tube, letting it warm up before listening to the second tube seems to take a bit too long to be completely trustworthy unless the differences are very obvious.

Any pointers would be helpful. Thanks!
Jonathan

 

[edisonwu]

These may help. Pictures are from Tubeworld.

 

[doubletaps]

Certain manufacturers have their own signature "house sounds" if i am not wrong.

If you look at the tables that edisonwu has kindly provided you will see that Mullards generally populate the "warm" sounding category and Telefunkens are genrally thought to be as very transparent.

When you get new tubes, having a familiar track to listen to is a great help of course, but don't forget to allow time for the tubes to break-in.

Doing the A/B over a few days would be preferred as then you would have enough time for the tubes to settle down and see which sound you prefer.

 

[Dept_of_Alchemy]

For 5687 it's quite easy, Tung-Sol is generally considered as best, while some like the JAN (joint army-navy) types as well.

Welcome to tube amps, sorry about your wallet.

 

[Kahuna]

edisonwu, do you have a website link for additional tables on other tubes you could share? (T.I.A.)

 

[sacd lover]

Quote:

Originally Posted by jopagi /img/forum/go_quote.gif I've recently purchased my first tube headphone amp -- a SinglePower PPX3 with slam. Being brand new to the whole tube world, I'm finding myself lost in the forest a bit... (but what an interesting place to get lost in!) A few pointers would be helpful. I've looked through the tube FAQ and didn't see what I was looking for. I can easily look up the 5687 tube and find equivalent or near-equivalent tubes. But how do I know which tubes produce which sound characteristics? If I'm looking for a brighter top end, or more air, or warmer midrange, etc. are there websites with this info? Do I look for certain tube specs? Are the sound characteristics of a particular tube different from amp to amp? And once I get some new tubes, are there any preferred techniques for A/B testing? Of course, I don't have two identical rigs that I can compare. Listening to one tube, powering down the amp, letting it cool down, then replacing the tube, letting it warm up before listening to the second tube seems to take a bit too long to be completely trustworthy unless the differences are very obvious. Any pointers would be helpful. Thanks! Jonathan

There really are no hard and fast rules to tuberolling. No one can tell you exactly how a tube is going to sound in your system to your ears. The chart that Edisonwu provided is only a rough guideline of someones (or a few someones) subjective opinion of the tubes. I have some of those 12AU7 tubes in those charts. However, I know I would not give them the same characterization in my setup.

Certain manufacturers had some degree of a house sound, but again, that is a very broad generalization with many exceptions. There is also no rating for the quality level .... which again is personal. You will find the same tubes in different amps will be said to offer differing characteristics. You will find the same tubes in the same amps will be attributed differing characteristics depending on what is upstream feeding the amp. Some people will love a tube and another person with a similar system will give you the complete opposite opinion. There is no substitute for listening and that is what you need to do.

You may see some of these charts for certain tube types .... but most will not have any. Millions upon millions of 12ax7's were made and used in lots of designs, so you see a good amount of information on that tube. But, for most that is not so. I can tell you I know of no charts detailing what characteristics the various 6cg7 tubes will have, and especially, what characteristics the 6gu7 tubes will have.

Electrical specs will show you what would be a potentially good use for a tube for a particular function. But, designers bend those rules too. One of the most widely used power tubes for headamps is the 6as7/ 6080. These tubes were designed for use as regulator tubes in dc power supplies. You will not find opinions on this tube for audio use anywhere but hobbyist websites.

The best information will come from people who own the particular tube amp you do. For one, different amps use different tubes, so you need opinions on the tubes your amp uses. The other amps that do use these tubes almost always combine them with other tube types .... which will give you and end sound of a tube combined with the sound of another tube .... which is usually not consistent.

People want absolute answers. But, you will not get them in this case because there are simply way to many variables. The good news is tubes really do sound different. However, you need to do the sampling yourself. The bottom line is not how people say a tube sounds .... but how the tube sounds to you. If you listen you will have definite favorites. But, your opinion of the sound of the tube in your amp may be completely opposite others. Dont worry about that .... trust your own ears.

 

[sacd lover]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif For 5687 it's quite easy, Tung-Sol is generally considered as best, while some like the JAN (joint army-navy) types as well. Welcome to tube amps, sorry about your wallet.

No ... it is not that easy for the 5687 or any other tube. While the TS 5687, for example, is typically acknowledged as the best 5687 there are different production years that are better. The later O getter TS 5687's are just not as good sounding as the older D getter types, again, in most peoples opinion including mine. There are some other really good 5687's, like the Sylvania 5687WA, Sylvania gold brand 5687 and the older Raytheon square getter 5687's which could easily be preferred over the TS 5687.

The TS 5687's in my equipment sound clean, fast, clear sounding tubes with a potent low end .... to me. Put them in a brightish amp or combine them with another bright tube type and you may not like them. A mellower Raytheon would probably be more to your liking. If I am using a TS 2c51 in the PPX3 SLAM for gain I prefer to use the Raytheon 5687 vs the TS 5687.

There are also variants to the 5687 .... like the Bendix 6900, various 7044 like GE/ Sylvania etc... and the Amperex 7119. You will read comments by people that would take the 7119 over any 5687. The Bendix 6900 is one of those rare, very expensive tubes hyped to be the ultimate 5687 substitute .... and the two I had sounded overly analytical and edgy. I plain did not like them and was very disappointed.

People tend to hear a tube in their amp with their anciliaries and if the sound of one tube seems best they conclude that tube is the ultimate and say so. Well .... the tube probably is the ultmate for them. But, the tube almost assuredly will not be for everyone. That said, certain tubes seem to garner almost everyones favor, except for a few dissenters. I can think of a few .... TS 5687, TS 6550, Mullard EL34, RCA 6CG7, Sylvania VT-231, Hytron 5814A etc...

But, in summary, there is no hard and fast answer someone can give for the best tube. There are some good starting points with tubes that always seem to garner favor. There is information on lots of different tube gear that can be a starting point. But, you still need to listen. Tuberolling is not a science with absolutes.

 

[jopagi]

Thanks so much for your responses everyone. I know there aren't any hard and fast rules (are there any in audio?) but I wanted to make sure I wasn't missing anything obvious.

I'm looking forward to doing the comparisons!

 

[sacd lover]

If your SLAM has a 9 pin socket for the gain position you will use 6cg7 or 6gu7 tubes. I would definitely recommend trying some 6gu7's. This tube is more airy and open sounding than the equivalent brand of 6cg7 and has about the same tonality and overall goodness.

The RCA and Sylvania are my favorites. This tube only costs around $5 per tube .... a real bargain. RCA 6cg7's are getting expensive.

The Tung Sol D getter is my favorite 5687. You can get this in consumer form or as a JAN military tube. I am also very fond of the Sylvania 5687WA military tube .... or the gold brand version of the 5687. The Raytheon 5687 is a good tube in square getter or O getter form. GE and RCA made 5687's but I find them a notch below the 5687's already mentioned.