Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

[Kommerzbassist]

Hey guys, how important are the 2nd gain-stage and phase inverter tubes for the ammount of preamp (&/or power amp?) gain?

thanks

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

Come on... you talk about tubes all day long... you must know

 

[Lake Placid Blues]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

They are important. On a BF bassman swapping different PI tubes had a noticable effect on at what point the power amp would start to breakup. A poor quality PI can cause a tube amp osculate some and do other wierd things.

On my Marshall Jubilee amps the V2 tube does effect the tone quality of the OD channel. Perhaps not as much as V1, but it's noticable. Marshalls are hard on V2. A cheaper or worn out V2 will tell on the tone quality, and they seem to wear out faster in the V2 position.

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

thanks for the info

 

[Lewguitar]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

I agree. Blackface Fenders came with a 12at7 phase invertor and Marshalls used a 12ax7 in the same spot. Swapping that 12at7 tube in a BF Fender for a 12ax7 will give the amp more of a grainy sounding drive. After a fair amount of experimenting, I prefer the 12at7 in an old Fender though...just sounds "right". Lew

 

[jimmy]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

If you put a Soldano Hot-Mod in there, it'll turn your amp into a little monster.

 

[slightly_rude]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

Jubilees use clipper diodes for gain boost in the lead channel. V2 is the tone stack and it affects both channels.

 

[Quencho092]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

lew, what tube do you reccomend as a phase inverter in a fender?

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

Ok after reading this again, I noticed my question is actually only ansered "a bit". I want to know if those two affect the gain of the amp, so if I put a high output tube in one of those, will I get mucho more gain?

 

[kmcguitars]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

lew, what tube do you reccomend as a phase inverter in a fender?

Read post #5 Lew already answered your question.

 

[drew_half_empty]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

PI tubes actually affect your gain quite a bit

i swapped out my GE 12at7 for an electro harmonix 12ax7 and could definately tell a difference in gain, and my amp doesn't use a gain stage so, take that as you will

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

PI tubes actually affect your gain quite a bit

i swapped out my GE 12at7 for an electro harmonix 12ax7 and could definately tell a difference in gain, and my amp doesn't use a gain stage so, take that as you will

Uhm... every amp has a gain stage... I think... I mean... those are the preamp right?
But well... thanks for the PI info.

Btw do 12at7 have more output than 12ax7 or less?

thanks

 

[Marcel]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

I dunno if there is a definition for gain stage... but afaik:
Modern amps like: SLO, Rectos have 5
5150: 6

older amps 2-3 ...

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

I dunno if there is a definition for gain stage... but afaik:
Modern amps like: SLO, Rectos have 5
5150: 6

older amps 2-3 ...

We're talking about what the tubes are used for rather than tubes themselves... so my TSL has 4 preamp tubes: V1/V2 are the gain Stages, V3 the PI and V4 is for the effects (I think only reverb)

 

[Marcel]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

yeah every tube has 2 triodes....
yeah i got a bit offtopic ;(
Chinese 9th Generation 12AX7 rock btw

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

yeah every tube has 2 triodes...

Ok this is also a way to look at it

Chinese 9th Generation 12AX7 rock btw

I have only replaced V1 with a Sovtek so far, and I like the tone, but I could use more gain, so I want to replace the other spots that don't affect the tone somuch but maybe the gain.

 

[drew_half_empty]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

what i meant was it wasn't really meant to be distorted/overdriven

 

[Marcel]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

I put GT12AX7C (which is a relabeled selected 9th gen) in the V1. It sounds warm, tight, more gain (?), more punch, fatter tone from what I heard...

compare GJ article in the vault....

I'm not sure but I think V1 adds the most gain and changes the most tone...

The TSL should have enough gain stock. If you want it all a bit fatter and tighter try a OD (tubescreamer) in front...

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

The TSL should have enough gain stock. If you want it all a bit fatter and tighter try a OD (tubescreamer) in front...

I swapped the V1 with a Sovtek LPS (because of GJs shootout) which is a fairly low output tube actually... but I still have the others stock, so I thought I could put some high output ones in there...

 

[Kommerzbassist]

Re: Tube question: Importance of 2nd gain stage & phase inverter gain-wise.

what i meant was it wasn't really meant to be distorted/overdriven

What? Ok... did the 12ax7 give you more or less gain now?