new to tubes

Listen to the PX25 tube...there is no doubt that this tube has more grunt...it is faster handling transients than a 300b, and not as warm, nor is the bass response as rolled off. If you listen to tubes within a line, you will find that every line imparts some bias...Cary and Audio Note are darker overall than Audion. But there are characteristics of each tube that transcend the lines, and may be magnified in some product lines, and diminished n others, but those characteristics define the sound of the tube. You need to decide what is important to your ear. If you like hard rock music, perhaps the EL34 or PX 25 would be a better choice than a 300B? Vocals and string instrumentals, acoustic guitar, the female voice, perhaps the 300B is the tube for you. Big soundstage, technicolor...maybe KT88s. Just make sure you listen to the tubes in the equipment that you intend to purchase, including the speakers and the front end. And you owe it to yourself to listen to Single Ended amplification before you decide.

Thanks for everyones' comments.

Mcpody - the manufacturer states that you can roll the KT88s EL34s and 6550s; can you explain how the PX25 and 300B fit into that equation - txs for your help

Facten ; are you sure that it says EL34 and not EL84 ? The 84's are usually transferable with 6550's and KT 88's .
What model is the amplifier in question ?

+++ The 84's are usually transferable with 6550's and KT 88's +++

Not sure how a KT88 or 6550 will fit into an EL84's socket or vice versa. The EL84 is a much smaller tube. They [KT88 & 6550] use identical tube sockets to EL34s, 6L6s etc and these tubes are interchangeable in many amps.

KT88, 6559, EL34 are NOT interchangeable with 300Bs

Regards
Paul

Sorry, but you cannot use teh PX25 or 300Bs in your system. I was just using the 300B and PX25 as an example of tubes that have generally acknowleged sonic signatures, because the previous comments stated that the sonic signatures were totally equipment dependent, and that is not true. With the tubes that you have mentioned, the EL34s will give you the best mids, the KT88s the biggest soundstage and a technicolor presentation, and I am not familiar enough with the 6550s to give you a fair assessment.