Hello Deramg. The two outside tubes are the 5687's. The 5687 is a dual triode developed for use in computers. The original nos tung-sol black plate 5687 is "far and away" the best sounding tube of that type. You may also substitute the 5687 with a 6900 or 7044 [ direct plug in replacements]The two inside tubes are 12au7/ecc82 dual triodes.The Ei ecc82 isn't a bad sounding tube but can be vastly improved upon with many brands of nos 12au7/ecc82 types but it is imperative that they are quiet and non microphonic. The early 60's vintage amperex bugle boys are terrific in that spot.
Preamp Tubes for KR AUDIO 18 BSI
I need some help on this amp here, i've done searches with the tube # on the internet and nothing really shows up...
what can i use to replace those 4 input tubes?
it will be such a great help...
going to modify it and going max, heard the result is nirvana...
Even now, im' at 90% of satisfaction, and so far i never gives me a problem.
what can i use to replace those 4 input tubes?
it will be such a great help...
going to modify it and going max, heard the result is nirvana...
Even now, im' at 90% of satisfaction, and so far i never gives me a problem.