CV4004 / 12AX7, Matched Pair

Everything about tubes must be said in context of the circuit they being thrown into and multiplied by taste. But...This is one of best sounding tubes I've tried. It has slightly less gain than long plate mullards but much smoother response in lows and highs. Accepts boost well. No noise until I crank gain and boost it.BTW, long plate mullard and sovtek LPS are the same tube. So, if you tried one of those, you already must have tonal representation of the CV4004.Works well in Marshall-based circuits if you prefer a bit darker sounding MarshallWorks best in already dark-sounding/boomy circuits.If you look for something more midrange-focused, it might be not for youI can recommend to try this tube. Not sure whether you like it or not in your amp, but if you look for replacement, try this one.

Excellent quality tubes. Had to replace the tubes in my amp and these did the trick! Shipping was phenomenally fast! Overall, a great product at a reasonable price. Will certainly purchase again if I ever need tubes for my other amps.

Wow! Bought these just before Russia invaded Ukraine! They work as they should. Mullard tubes have always been good to me.

These are probably the best replacement tube for your 12ax7'sSimple.

Great set of tubes, really smooth out harsh distortion, I've put Mullards in every amp I own.

High quality tube sound at a fair price. You need these!

Nice sounding tubes at a very fair price. used in a McIntosh MA352.

Sound good, tube good