Try some Amperex 6DJ8 Bugle Boy tubes for around $15 each and see what happens. They should change the sound of the amp and then you can go up the 6dj8 chain from there.
Improving the high end on SA100 (stock, based on my experience with the SA220) means u need to replace the coupling caps AND swap out the 6DJ8 with a something that has sparkle like the Telsa (new JJ or NOS)
Now if your SA100 has been "altavista'ed" thats another story.
I would like to help you Undertaker but I never remember what mine are when I change,and I just did.All I know is they were 6sn7's,but thats because I have the new upgrades.I have to say to email Mike at the website as he is very helpful.Its a great little amp,hope your enjoying,Bob
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