For a comprehensive discussion and listening comparison of 11 variants of KT88/KT90/6550 tubes, see issue #19 of Vacuum Tube Valley. It can be ordered here.
6550 tube vs KT88
Was wondering what might be some of the differences between these 2 tubes. I've heard 2 sets of 88's and was not a tube that fits my music, classical. i found the sound too compressed, too flat on fq's, dynamics were thin. Too warm, not detailed like the KT90 tube.
Is the 6550 a middle of the road between the 2?
Hows the timber? bass/mids/high separation?
The KT88 seems to blend the 3 too much.
Is the 6550 a middle of the road between the 2?
Hows the timber? bass/mids/high separation?
The KT88 seems to blend the 3 too much.
Showing 5 responses by tvad
Bartokfan, you should do some homework before writing, because you really don't know wtf you're talking about. Your Jadis Orchestra (correct?) at 40wpc simply does not have enough power to drive 87db/1w/1m loudspeakers. It doesn't matter what tubes you're using. You don't have enough juice to recreate dynamic passages, especially in classical music. Period. The following is taken from a review of the Orchestra here on Audiogon. The limited power output means it struggles with vivid dynamic passages at loud volumes. It really can't render a concert grand without clipping - as a trial I'd suggest Emil Gilels' recording on DG of Beethoven's "Pathetique" - the chords crash and so does the amplifier. Yet, turn down the volume to what you might experience twenty rows back in an auditorium, and everything is fine - fantastic ambience, wonderful tone. You might find some KT88 tubes that work well in the JOR, and they might be found in the Vacuum Tube Valley Issue 19, but your problem with the sound of KT88 tubes has nothing to do with the tubes, and everything to do with your mating of a 40wpc tube amp with 87db/1w/1m loudspeakers. I owned a KT88 tube amp that produced 110wpc, and it created clean sound pressure levels of 105+db in my listening room with moderately sensitive loudspeakers like yours. IMO, FWIW, Amen, All Praise to Allah. Kumbaya. |
I'm also not sure that your amp, apparently designed to use KT90's, is really a good candidate for KT88's as drop-ins.Zaikesman makes a cogent point that amplifiers are usually voiced with a particular tube, regardless of their ability to function with several types of tubes. 11-01-00: RcprinceTherefore, it's likely an amp sounds best with a particular tube from a specific manufacturer (in the case of Jadis, the Ei Yugo KT90), and one cannot make generalizations about the quality or suitability of other tube types based only on one's limited experience with one amplifier that has been specifically designed for a particular tube. In fact, the JOR will probably sound different with Electro Harmonix KT90 than it does with Ei Yugo KT90. |