cayinA100 T tube amp

It sounds like you are still getting to know your amp? You may want to give it a little time first and then roll some NOS or new tubes first and see what you think.

Some integrated amps can be enhanced by using a nice preamp. The Jolida's are a good example of that. They are basically an amp with a volume control. I'm not sure if that is how the Cayin is set-up? Anyway even if you add a preamp you will be using most if not all of your tubes anyway in your amp anyway. In my experience tubes will make a big difference.

I truly don't think you should give-up on your amp before seeing what it can do with some nice tubes. If you do add a preamp stay with tubes. Just my two cents

From what I have read in reviews, the amp in the 88T and 100T are very very good. I recommend what Detredwings said and roll some tubes 1st. If you still are not satisfied then go with a preamp.

It is easy to change the amp's tone by making changes in the power tubes and the small tubes if what you want is a different tone. I did. You can start with different KT88's or 6550's. But you've got to have a goal in mind.

You can increase clarity some by using a high quality preamp but I wouldn't spend my money on a new preamp just to get a different tone.

I have an A100 and drive it with a preamp connection. The preamp I use is the VAS Citation I, made by Cayin's parent. I also use the VAS Citation to drive VAS mono blocks, in a three channel configuration. Very happy with the 'Cayin' sound. I do notice a significant difference when I use the preamp to drive the A100, even beyond the Phono inputs which was the main reason I acquired the Citation. When I drive the amp with cd input, there is less of a difference, but still noticeable. Tubes make all the difference. I have not done any tube rolling, yet. I also have a Cayin T88, which is not in use. I moved up to the 100 for more power and it made a significant difference. I drive different sets of ProAC speakers.