This valve was one of my two choices out of six in total, to use with my guitar tube pedals. It behaves well under all tested circumstances: from cleans to heavy metal riffs. Compared to the other 12AX7 brand, this one was *slightly* towards the high-end, *a bit* less low-end feedback, therefore I chose this one for the distortion pedal. Other than that, they are both great tubes and their sound is powerful, defined and versatile: neither too bassy, nor treble and aggressive, just by no means low gain.