6FQ7: gif1, gif2, gif3, gif4 Bold designators are close or identical, Italic designators are different ratings, different pinouts or different filament voltages. Please see the substitutes at the top of the page for more details The TELEFUNKEN ECC83-TK is a well-balanced tube suited for all types of music and playing styles. Designed to allow for cleaner headroom than higher gain 12AX7s when pushed into overdrive, it offers distortion with strongly defined lows, a rich mid range and clean, smooth highs.
6CG7: Courtesy Bureau Belper (De Muiderkring, Bussum), Scan Frank Philipse Michael Schlör vacuum tube data sheet TESLA RE 40 AK / KT 88 BEAM TETRODE manufactured by Tesla Vršovice s.r.o. Czech Republic Brief data The RE 40 AK has a designed maximum anode dissipation rating of 35 W and