Crack;Bottlehead OTL

[FunyunBreath]

Yeah thats the worst thing about tubes, and the reason why I'll never shell out more than $100 for a single tube. A $250 GEC brown base is worthless if it develops a hum a year later.
 
Might not bother some people that much but my amps have to be dead silent or it just drives me crazy.

 

[DDDamian]

I hear ya. I can ignore it but that's not the point of high-end audio lol.
 
Anyone tried dampers on that shape of a tube?
 

 

[Mich4lle]

Hello guys,

I have another question, I am about to buy a Tung-sol 5998 and an Amperex 12AU7 tube. I just got test results for these tubes and am just curious if they are good. I know that I should be able to read these results but they seem to differ based on the tube tester you use. Or at least as far as I know. Anyway so if somebody can tell how to to read these results that would be great.

5998

eG1 10.8 / 10.1 V
GM 14.56 / 15.00 mA/V


12AU7

GM 13.91 / 13.62
Gain 16.3 / 16.1
Noise 85.0 / 80.1

Thanks in advance for any help.

 

[adydula]

I emailed a person that sells the dampers for this tube and others, its a $50 option and fits on the fat part of the tube, I might try this in the near future after some more burn in and expeimentation,
 
I totally agree on spending mega bucks on tubes that are well "tubes" that can have worts or work well for hundreds of hours...its all part of the tube game!
 
Its a nostalgic thing for me, I grew up with these things and built radios, receivers and transmitters with 21+ tubes and did the alignments and biasing etc.....so putzing around is not a real issue just challenging at times regardless of the tubes used.
 
Besides they look cool all glowing in the dark!! 
 
LOL
 
Alex

 

[FunyunBreath]

Hello guys,

I have another question, I am about to buy a Tung-sol 5998 and an Amperex 12AU7 tube. I just got test results for these tubes and am just curious if they are good. I know that I should be able to read these results but they seem to differ based on the tube tester you use. Or at least as far as I know. Anyway so if somebody can tell how to to read these results that would be great.

5998

eG1 10.8 / 10.1 V
GM 14.56 / 15.00 mA/V


12AU7

GM 13.91 / 13.62
Gain 16.3 / 16.1
Noise 85.0 / 80.1

Thanks in advance for any help.

 
GM is the measurement of plate current on each channel of the tube. To be honest the measurements really don't mean much unless the seller knows what they're doing and has accurately calibrated gear. There's only a few sellers online that I'll purchase high-priced tubes from because I know they have proper testing methods. Otherwise i'll only take a chance if they have a 14-day return policy

 

[DDDamian]

Hello guys,

I have another question, I am about to buy a Tung-sol 5998 and an Amperex 12AU7 tube.

I wouldn't be quite so paranoid. Every tube (even NOS) is a crap-shoot. If the seller has a decent reputation or an credible online business your odds are better than the usual crapshoot. As FunyunBreath says - check for a return policy.
 
Even to reliable sellers the same adage applies: "How long does a light bulb last?". Sure - they have a finite life, some go dim fast, some pop when you turn them on. Wanna roll you gotta play.

 

[JamieMcC]

  I emailed a person that sells the dampers for this tube and others, its a $50 option and fits on the fat part of the tube 

 
Does it look anything like this

 
http://www.amazon.com/SEOH-Flask-Weight-Vinyl-Lead/dp/B0088AR3K4   $3.62
 

 

[Mich4lle]

I wouldn't be quite so paranoid. Every tube (even NOS) is a crap-shoot. If the seller has a decent reputation or an credible online business your odds are better than the usual crapshoot. As FunyunBreath says - check for a return policy.

Even to reliable sellers the same adage applies: "How long does a light bulb last?". Sure - they have a finite life, some go dim fast, some pop when you turn them on. Wanna roll you gotta play.

Well that makes me feel better because I am buying it from vacuumtubes.net which I have only heard great things about and their responses have been great so I think I am going to go for it. Thanks for the help guys.

 

[DDDamian]

Well that makes me feel better because I am buying it from vacuumtubes.net which I have only heard great things about and their responses have been great so I think I am going to go for it. Thanks for the help guys.

Best of luck. Yes they're a reputable seller and I think you'll really enjoy those tubes!

 

[adydula]

It looks like this from Herbie Audio:
 


Alex.   

 

[FunyunBreath]

Well that makes me feel better because I am buying it from vacuumtubes.net which I have only heard great things about and their responses have been great so I think I am going to go for it. Thanks for the help guys.

 
Vacuumtubes.net are awesome guys, I've bought my last few 5998's and 7236 tubes from them and they've all been great.

 

[Whit3Rav3n]

I found a Siemens Silver Plate input tube. Does anyone know if it is any good in the bottlehead?

 

[FunyunBreath]

Siemens silver plate tubes are among the best 12au7's you can find!
I've been on the lookout for a deal on one but haven't come across any yet.
 
On another note, anyone else tried the RCA cleartop + Tung Sol 7236 combo? I was never really a fan of the cleartops because I felt like they had too much emphasis on bass/treble and not enough mid-range goodness. Turns out I was just using them with the 5998 and in my opinion that's not a good combo for a more neutral signature.
 
The cleartop has bass extension and slam where the 7236 lacks, and the mid-range emphasis on the 7236 makes up for the lack of mids in the cleartop. An amazing combo for rock and vocals!

 

[Mich4lle]

Vacuumtubes.net are awesome guys, I've bought my last few 5998's and 7236 tubes from them and they've all been great.

I just gave the go ahead, and I am so excited to hear what all the rage is about.

 

[DDDamian]

I just gave the go ahead, and I am so excited to hear what all the rage is about.

Hope to read your impressions