Doubt about EH 12ax7 tubes

[hellraiser85]

Hi! I bougth 5 Electro Harmonix 12ax7 preamp tubes to install in my 5150.

3 tubes has written this numbers on it: 08 09.

And the other two has written: 07 07.

What does mean these numbers?
Maybe the "07 07" tubes are balanced tubes (to put in the phase inverter position)??

Thanks!

 

[53Crëw]

I'm pretty sure it's just the date code of when they were made. (Year/Month)

September '08 and July '07

 

[hellraiser85]

Ok! thanks for the info

 

[VH100R]

nice preamp tubes. I love them.

oh yeah... probably the month/year