[Jack C]

Quote:

I'm probably gonna purchase a used tube amp within the next few weeks, seems like there's a lot of supporters on headfi for tube amps so I guess I can't really go wrong   Anyway just to ask, how would one know if it's time to replace a particular tube for the amp? Would there be indicators aesthetically, such as the tubes becoming black or something similar? 
 
One question about solid state amplifiers though, from what I've read on the forums a lot of solid state amps try to present a more neutral sound, without any colouration or artificial warmth. The more expensive the amp generally the more accurate sounding (aka neutral) songs would be - correct me if I'm wrong here I'm kinda making an assumption - but wouldn't there be a point where too much neutrality would actually make the sound seem 'lifeless', in a sense? What is it about very high end solid state amps that attracts people ? Not sure if I'm putting it correctly as I don't have much experience in amps of any kind...

 
If you are going to be purchasing a fairly new design, then no problems, just get it and enjoy. No problems whatsoever. Just visually inspect the amp for physical damage. If you don't see any, then it's most likely just fine. You only have to be careful when buying really vintage stuff, like when I helped a business contact in China purchase a Marantz 8B from a US seller. That amp had to be fully inspected by someone who was very familiar with it before being turned on the first time.
 
Jack

 

 

[Skylab]

Usually a tube will start to sound notably bad before is goes fully bad, or will exhibit some "purple haze"/glow (although that is not always an indicator of a bad tube).  Most tubes fail on power-up, when they're going to fail.
 
And yes, one reason I think that tube amps have a popularity is that SOME SS amps do have kind of a lifeless, threadbare sound.  But IMO only a small minority of SS amps are like this, just as only a very small minority of tube amps are notably "syrupy".  The two technologies these days are far more similar than different in terms of the sound they end up producing. 

 

[voodoohao]

So technically tubes would be able to last for several years, as long as they do not spoil at the start... will the glass become cloudy or burnt though, but might be still working fine?   Will a tube amp require any sort of maintenance from the user, such as cleaning it etc?
 
 
 Anyway I've really learnt a whole lot from the replies to this thread, so thanks again to those who have replied!
 
The next thing I'm going to do is to audition a Darkvoice 337 this weekend, might be buying it if I'm really wowed by the sound. So hopefully it all goes well
 
 
 

 

[Skylab]

Yes, most tube amps would have the tubes last for years, and almost all headphone amps are self-biasing, so they need no maintenance.
 
I have seen tube amps that were working, with the original tubes, 50 years after they were made!

 

[Zoldar]

Nice topic.
 
Skylab, I have recently taken the plunge into tubed amplification. You mentioned purple haze. See the picture below of my Graaf GM50 (KT90 tubes).

 
 
Question: should I worry? 

 

[9pintube]

JMO...."IF DON'T GLOW, IT DON'T GO"

 

[Frank I]

I have had tubes like this in my 6550 amps most notably the SED 6550 and was told not to worry about the blue it actually was a good seal. There is a good thread at audio asylum in the FAQ section regarding the blueish tint. I can say I ran those tubes without incident for years in my CJ Premier 11a
 
Quote:

Nice topic.
 
Skylab, I have recently taken the plunge into tubed amplification. You mentioned purple haze. See the picture below of my Graaf GM50 (KT90 tubes).

 
 
Question: should I worry? 

 

[Skylab]

Quote:

Nice topic.
 
Skylab, I have recently taken the plunge into tubed amplification. You mentioned purple haze. See the picture below of my Graaf GM50 (KT90 tubes).

 
 
Question: should I worry? 

 
No need to worry.  Power pentodes have a blue glow.  Even the EL84's do this.  My 6V6G's all do this.  Perfectly normal.
 

 

[voodoohao]

Hmm I realised that there are several types of tubes and certain types of tubes would not be usable with certain tube amps, the Darkvoice 337 can only use 6SJ7 while the 336 can only have the 6SN7 attached to it. Would I be able to identify the type of tube just by looking at it? ( Would it be stated on the tube itself ? )  Does it mean that 6SN7 tubes cannot fit into the Darkvoice 337 and vice versa?

 

[9pintube]

Quote:

Hmm I realised that there are several types of tubes and certain types of tubes would not be usable with certain tube amps, the Darkvoice 337 can only use 6SJ7 while the 336 can only have the 6SN7 attached to it. Would I be able to identify the type of tube just by looking at it? ( Would it be stated on the tube itself ? )  Does it mean that 6SN7 tubes cannot fit into the Darkvoice 337 and vice versa?

People, Especially you dudes new to TUBE Amps or other Tube Equipment, need to realize that just because a tube fits into a (Let's say a 9 pin tube socket,or an Octal socket) doesn't give one "the green light" to start "Tube Rolling" or swapping....If your tubes markings aren't readable check with someone who can tell by looking at the tubes "Guts" for  lack of a better word....Your Tube amp Manufacturer should be able to let you know what tubes can SAFELY be used in the Amps or Pre-amps circuit......Not only can this damage other parts in the amp/ other TUBE gear but why chance frying something..........Now, Tube rolling different Brands of the same kind (6sn7, etc.etc.) is Safe in most cases.......JMO from an older Tube Guy!

 

 

[Skylab]

Quote:

Quote:

Hmm I realised that there are several types of tubes and certain types of tubes would not be usable with certain tube amps, the Darkvoice 337 can only use 6SJ7 while the 336 can only have the 6SN7 attached to it. Would I be able to identify the type of tube just by looking at it? ( Would it be stated on the tube itself ? )  Does it mean that 6SN7 tubes cannot fit into the Darkvoice 337 and vice versa?

People, Especially you dudes new to TUBE Amps or other Tube Equipment, need to realize that just because a tube fits into a (Let's say a 9 pin tube socket,or an Octal socket) doesn't give one "the green light" to start "Tube Rolling" or swapping....If your tubes markings aren't readable check with someone who can tell by looking at the tubes "Guts" for  lack of a better word....Your Tube amp Manufacturer should be able to let you know what tubes can SAFELY be used in the Amps or Pre-amps circuit......Not only can this damage other parts in the amp/ other TUBE gear but why chance frying something..........Now, Tube rolling different Brands of the same kind (6sn7, etc.etc.) is Safe in most cases.......JMO from an older Tube Guy!

 

 
All true, but generally, you can in fact identify the tube type by reading the designation right on the tube.  A safe rule for newbies is not to replace the tubes at all unless you are 100% completely sure that the tube you are about to use will work in the amp in question.  There are literally thousands of different types of tubes.
 

 

[9pintube]

 
Quote:

 

All true, but generally, you can in fact identify the tube type by reading the designation right on the tube.  A safe rule for newbies is not to replace the tubes at all unless you are 100% completely sure that the tube you are about to use will work in the amp in question.  There are literally thousands of different types of tubes.
 

GREAT ADVICE Skylab, maybe the younger guy's will listen to you!!!......Rolling Tubes does change the "sound" many times for the better, but don't you agree , Skylab, that guy's shouldn't really change tube types......without checking with the amps manufacture???Tell them again, I'd hate to see some guy's burn-up or cause a melt down to their TUBE GEAR, because THEY think Changing Tubes will get them to the "Holy Grail" of sound!!!!  duke
 

 

[Frank I]

X2 on Rob advice. Use on the tube types the manufacture recommends which will be in the manual. Also there is guides on what can be swapped on some dealers sites. I always ask the manufacture when i am not sure or my dealer. build a relationship with a reputable tube dealer. the tow I use most are Jim McShane and Tube Depot. I have been using those two for the last 15 years with zero problems. I had a friend who wanted to put little dot tubes into a Millett starving student. he asked me and I told him no way. But for newbies read and learn as much as a you can about tube technology. The audio asylum has a great tube thread and Joe's tube lore is a must read on that site. I like swapping but once I find the right combo I live with them for a long while. Ask questions here between Skylab and many others you will always get the best answers.

 

[InnerSpace]

Think of tubes like the tires on your car.  You have to stick with the right size, but you can choose between brands in order to get the characteristics you want.  In some cases you could go a little lower and wider, but you have to know exactly what you're doing in order not to foul the brakes or the suspension members.  Same with tubes.  99% of the time you swap like for like, but you really need to be careful about swapping types.

 

[Jack C]

Quote:

Think of tubes like the tires on your car.  You have to stick with the right size, but you can choose between brands in order to get the characteristics you want.  In some cases you could go a little lower and wider, but you have to know exactly what you're doing in order not to foul the brakes or the suspension members.  Same with tubes.  99% of the time you swap like for like, but you really need to be careful about swapping types.

I like this analogy!
 
Jack