Do new tubes have a break in period?

[ixoye777]

Just curious, I can't seem to tell because if they do have a break in period I think I get used to them as they slowly break in and I can't tell. If so how long until they are fully broken in?

 

[212Mavguy]

Yes, depends on the tube. Can be as much as 100 hours, and as little as ten. Preamp tubes tend to take longer.

 

[kiff]

How do they change?

 

[MusicManJP6]

How do they change?

Good question.

 

[kiff]

i know older preamp tubes have more gain, since their lower vacuum makes them break up faster, but I'm wondering (and I assume you do too MusicManJP6) what effect breaking in a power tube has on its tone.

 

[fluff191]

I was thinking about this the other day, because I have noticed a change for the better in my Recto just recently, and have had the power and preamp tubes in for about 4 months.

IMO its a bit more responsive and "rounder" if that makes sense. The harmonics are slightly more pronounced. The difference is by no means huge, but they def. sound like the have dug in and made themselves comfy!

 

[212Mavguy]

I was thinking about this the other day, because I have noticed a change for the better in my Recto just recently, and have had the power and preamp tubes in for about 4 months.

IMO its a bit more responsive and "rounder" if that makes sense. The harmonics are slightly more pronounced. The difference is by no means huge, but they def. sound like the have dug in and made themselves comfy!

Good ears! As tubes break in, they tend to lose some of their high frequency response. The sound as a result tends to a more balanced, musical tone palette with break in. With some preamp tubes tubes such as the vintage Matsushita 12ax7 with the 45 degree getter flash, tendencies are to be a bit shrill and brittle sounding, and those take a fair amount of time in an operating circuit to roll off the top end to where they start sounding their best.

 

[MusicManJP6]

I was thinking about this the other day, because I have noticed a change for the better in my Recto just recently, and have had the power and preamp tubes in for about 4 months.

IMO its a bit more responsive and "rounder" if that makes sense. The harmonics are slightly more pronounced. The difference is by no means huge, but they def. sound like the have dug in and made themselves comfy!

Good ears! As tubes break in, they tend to lose some of their high frequency response. The sound as a result tends to a more balanced, musical tone palette with break in. With some preamp tubes tubes such as the vintage Matsushita 12ax7 with the 45 degree getter flash, tendencies are to be a bit shrill and brittle sounding, and those take a fair amount of time in an operating circuit to roll off the top end to where they start sounding their best.

Cool. Sounds alot like the tonal changes that occur as a speaker breaks in...