PI affecting tone?

[misterwhizzy]

I don't mean to sound like a noob, but I always thought the PI had more to do with feel than tone. I put in a Chinese tube replacing my old Amperex in the PI position, and I notice more sparkle and a bit more upper-mid presence. It's not a big deal, but the lows may also be a bit tighter.

This may be inappropriate to say on July 4th, but I'm really starting to dig the well-chosen Chinese tubes. They sound great.

 

[SongsForTheDeaf]

Re: PI affecting tone?

interesting... I just got JJs which I believe are stock in my couple month old Traynor YGL2 but I hope I see a bit more detail when I switch tubes in the future. What brand of tube was it ?

 

[misterwhizzy]

Re: PI affecting tone?

Ruby. I got a 12AX7AC5 HG+ a few months back for the preamp, and it sounds really great. So when it came time to get a backup 12AU7 for the PI, I went with Chinese as well. I had a JJ that got smashed, and it was fine, but this one makes a difference.

 

[Chickenwings]

Re: PI affecting tone?

might just be your amperex is a bit tired. the PI is the hardest working tube in the amp.

 

[TwilightOdyssey]

Re: PI affecting tone?

might just be your amperex is a bit tired. the PI is the hardest working tube in the amp.

+1.

Probably not an improvement but a restoration caused by using a newer valve...

 

[MrTondo]

Re: PI affecting tone?

Funny thing is though, you now all admit a bad PI-tube has influence on your sound, yet a good one doesn't .

I get it though, when the power cuts out, it cannot do its work anymore, and responds nonlinear to the input signal frequency wize. But would a solid state PI sound different than a tube one? Food for thought .

 

[misterwhizzy]

Re: PI affecting tone?

In a lot of amps, our ears confuse PI clipping with power tube overdrive, so in many cases, a tube PI would sound much different than a solid-state.

 

[Chickenwings]

Re: PI affecting tone?

Funny thing is though, you now all admit a bad PI-tube has influence on your sound, yet a good one doesn't .

I get it though, when the power cuts out, it cannot do its work anymore, and responds nonlinear to the input signal frequency wize. But would a solid state PI sound different than a tube one? Food for thought .

for sure a pi tube affects your sound. everything in your chain affects your sound.

 

[aleclee]

Re: PI affecting tone?

In a lot of amps, our ears confuse PI clipping with power tube overdrive, so in many cases, a tube PI would sound much different than a solid-state.

In a lot of amps, the PI clips long before the power tubes. A lot of what we think of as Marshall crunch comes from the PI.

 

[TwilightOdyssey]

Re: PI affecting tone?

In a lot of amps, the PI clips long before the power tubes. A lot of what we think of as Marshall crunch comes from the PI.

I find this absolutely fascinating and is something I never consdiered. I did some searching on Google and came up with this article. Fascinating stuff!

 

[Van Noord]

Re: PI affecting tone?

This may be inappropriate to say on July 4th, but I'm really starting to dig the well-chosen Chinese tubes. They sound great.

I think it's quite appropriate. Where do you suppose all those fireworks are made...?

 

[glassman]

Re: PI affecting tone?

Hey Will!

The 5th generation Chinese 12AX7s are the only 12AX7s that really stand out from all the other 12AX7s out there (except some JJs); as in the differences between all of the others are subtle while the 5th gen Chinese tube is pretty much a tube all its own. I use them to tighten up any amp that suffers from muddyness. They work in any position that suffers from a little too much bass but are most pronounced in V1 of about any amp. An amp that lacks bass to begin with can sound harsh and kinda wimpy though.

I stock three 12AX7s for repair work:
* Chinese 5th generation 12AX7s to tighten up bass heavy amps (or individual sections)
* JJ 12AX7s to give additional bottom end to amps that are a little too thin (or individual sections of those amps)
* Any of the other current 12AX7s that are reliable to use as a general replacement for amps (or individual sections) that don't need any help.

I realize that some people can hear the subtle differences between all of the other 12AX7s but almost all of the amps I service are performing amps where differences in raw character count and any subtleties get lost in the mix.

 

[misterwhizzy]

Re: PI affecting tone?

Hey, Jerry. I'm always happy when you weigh in on one of my threads. And it's because of you I'm NOT running a 12AX7 as a PI. It's a 12AU7, of course. And I'm pretty happy with that suggestion and that tube.

 

[jeremy]

Re: PI affecting tone?

might just be your amperex is a bit tired. the PI is the hardest working tube in the amp.

thats the truth right there. i swap preamp tubes for tone but replace the pi tube with the power tubes