Please ensure Javascript is enabled for purposes of website accessibility Jump to content

Tubes


psarkissian
 Share

Recommended Posts

Dear group, I can not emphasize this enough,...do not, do not, do not use anything other than the specified

tubes (valves) in these amps. Power tubes must be matched sets. Use only the specified tubes. Please, I'm

trying to keep your gear of of my repair bench, so you can make music and rock out.

 

Thank you.

Link to comment
Share on other sites

Tube choices to use,...

Spider Valve:

12AX7B China for pre-amps.

5881WXT Sovtek (matched pair), with the base cup bottom.

5881WXT Sovtek (matched quartet), with the base cup bottom for the HD-100 and HD100 MkII.

 

Soft, medium or hard, the ratio between vacuum-to-inert gas in the tube,... all tubes used have to be mediums

 

Low microphonic 12AX7EH for the pre-amp is fine.

Power amp tube choices are crucial, and must be properly biased by a tech or Line 6 authorized service center who knows the product.

Don't do this yourself, the shock hazard is too great,... and it hurts when you get electric shock. Leave it to a tech trained who is for this.

 

These valve amps are particular about tubes and tube brands. Do Not use substitutes, No Mesa, Groove Tube, Tung-Sol, Ruby or JJ substitutes. No hot rodding of an already Bogner hot rod.

  • Thanks 1
Link to comment
Share on other sites

For Alchemist users, it's not a simple tube replace and bias. There is a whole bias and burn-in procedure,

and calibration to be done, so leave the whole procedure of this one to the professionals (Line 6 authorized servicing).

 

Link to comment
Share on other sites

  • 2 months later...
  • 4 weeks later...

Can you explain why you cannot run JJ or Tung-SOL tubes? The service manual does not say this. It also does not state to use only Electro-Voice or Sovtek brand tubes. My MKI came with Sovtek 5881/6L6WGC power tubes. But not saying you should do what I did and run JJ 6L6GC's/Tung-SOL 12AX7s and make your amp sound totally awesome. They have different max wattage and voltage ratings. Perhaps the filament is larger and generates too much heat? I'm now curious as to why.

Link to comment
Share on other sites

Frankie,....No. Don't do that. Tubes are not arranged for that sort of thing.

 

Frankie, Mark,... these are not the all analog tube amps of the 1960's and 70's, these are hybrids.

Can not get away with doing these sorts of things like we used to do back in the day.

 

The analog and digital sections need to talk nice to one another. As a result, these amps don't take

kindly to modifications. Don't mod these amps.

 

Link to comment
Share on other sites

  • 3 months later...

Mark,...

It has to do with the subtle differences in the characteristic curves of the afore mentioned non-specified tubes.

The program board does not like those differences, and the analog portion doesn't like the digital sections response.

So it is imperative that the specified tubes are used.

 

Link to comment
Share on other sites

With tubes, the characteristic curve and the way it's loaded is a big deal, especially in a hybrid amp with

both analog and digital sections that need to function together. So don't try to mod these things. It's not

like the old days with all analog amps, when you could tube swap at will. Those days are gone here.

 

Link to comment
Share on other sites

  • 7 months later...

Hi I have one tube gone bad in my spidervalve hd100, can I change the bad valve alone, or do I need to change a pair or quad. In most valve amps the valves are working in pairs so i'd expect to replace a pair of tubes not a whole quad.

Link to comment
Share on other sites

  • 6 months later...

The key is to use correctly matched power tubes that fit the criteria of the amp. In this case, the ONLY hard criteria are 6L6/5881 tubes and that they be matched. I'm not saying the posters are incorrect, however, using other branded tubes that fit the criteria of the amp is NOT an issue. 

 

You CAN use ANY brand of tube so long as if fits the criteria. Do not limit yourself to the cheap tubes the amp came with. 

 

The waveform characteristics and interaction between the tubes will ONLY affect the tone. There will be no structural damage. The issue here is that different tubes will potentially yield different tones than the amp is intended for. This can be a good thing or bad thing depending on your tonal taste. 

Link to comment
Share on other sites

Flyers_V88,... with an all analog amp, I would agree.

16 hours ago, Flyers_V88 said:

The key is to use correctly matched power tubes that fit the criteria of the amp. In this case, the ONLY hard criteria are 6L6/5881 tubes and that they be matched. I'm not saying the posters are incorrect, however, using other branded tubes that fit the criteria of the amp is NOT an issue.

 

But using other brands, incorrect biasing and not know the hard/medium/soft of the tubes,.... it has resulted in a number of these amps ending on my bench.

These are not all analog tube amps, the digital section and analog section have to talk nice to one another, or things go wrong and they end up on my bench.

 

Normally I would agree with you, but in the case of these amps, the correct tube IS the issue in this case. So to everyone,... use the specified tube and bias,

and have a Line 6 authorized service center do it.

 

Seen too many blown amps for this reason. So please don't do that. I'm trying to keep everyone's gear off of my repair bench.

 

Link to comment
Share on other sites

4 hours ago, psarkissian said:

Flyers_V88,... with an all analog amp, I would agree.

 

But using other brands, incorrect biasing and not know the hard/medium/soft of the tubes,.... it has resulted in a number of these amps ending on my bench.

These are not all analog tube amps, the digital section and analog section have to talk nice to one another, or things go wrong and they end up on my bench.

 

Normally I would agree with you, but in the case of these amps, the correct tube IS the issue in this case. So to everyone,... use the specified tube and bias,

and have a Line 6 authorized service center do it.

 

Seen too many blown amps for this reason. So please don't do that. I'm trying to keep everyone's gear off of my repair bench.

 

Like I said, you're correct in that using random tubes or not matched, or incorrect biasing will result in the issues you described. 

 

PEOPLE, DO NOT REPLACE TUBES YOURSELF UNLESS YOU'RE A TRAINED TECH! ENSURE TUBE COMPATIBILITY AGAINST THE DEFAULT TUBE SPECS THAT CAME WITH THE AMP! MATCHED ONLY! ENSURE TO BIAS CORRECTLY! lol. 

 

My comments were basically assuming most competent tube amp owners know these basic facts haha. No matter the amp type, unless it comes with auto-biasing and can take different tube types, you always need to ensure the tube selection meets the performance requirements of the amp. I was just highlighting that if you know what you're doing, you can select alternate tubes to potentially achieve some changes in the amp's tone. 

Link to comment
Share on other sites

"... unless it comes with auto-biasing and can take different tube types, you always need to ensure the tube selection meets the performance requirements of the amp. "--- yes, as always.

 

"... that if you know what you're doing, you can select alternate tubes to potentially achieve some changes in the amp's tone. "--- unfortunately, not with these amps. Some of the blown ones that came back, were from competent techs who knew their stuff, and got in over their heads. The digital and analog sections of these amps have to talk nice to each other. These are not forgiving amps of even the slightest of modifications,... including tube swaps.

 

Unless people have a curve tracer, other special gear and know how to re-bias along a different load line,.... then please don't go there. I'm trying to keep everyone's gear off of my repair bench.

 

 

 

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
 Share

×
×
  • Create New...