Audio Research LS-15 Infincaps

He wrote "...Ei 6dj8". Ei is the abbreviation that a European company named something like Electrical Industries uses. They're available all over, are quite inexpensive, and certainly are among the best-value NP tubes around. Here's one source http://store.tubedepot.com/ei-6dj8eg.html among many. I've happy with my results with Ei 12AX7s, 12AU7s, and Tube Depot.

On your original question, here's an informed opinion about capacitors--
http://www.altavistaaudio.com/caps.html
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"I saw tubedepot on the web before, just dodn't know how reliable those guys are. Is it safe to buy tubes from them?"

Christian at Tube Depot has treated me very well over many transactions. He has accepted returns when I ordered the wrong things and has bias-matched my old Ei KT90s to the new ones I bought from him for free. He's a good guy.

Based on the pic of the LS15 here http://www.arcdb.ws/LS15/ARC_LS15_top.jpg , I'd say anyone who knows how to solder could replace those coupling caps with same-value better caps. Personally, I'd use the TRT D-Caps or Mundorf M-Cap Sup. S/Os, but you might also consider the V-Cap teflons, altho they're VERY expensive. But since you'd be saving the labor charge, maybe you could choose to afford them? Can you solder or have a friend who does?
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