Differences in tube sounds: 6550 / EL34

It depends on the application; In some applications 6550's are similar to SS amps-- Audio Research,for example.--AND of course 'what el34' matters,2.

I am considering two different integrated amps, one uses 6550, the other uses EL34. I am leaning toward the EL84 driven amp. What EL34 tubes do you suggest?

EL34 supposed to have more "lush" sound. 6550 are said to have better bass control. When i owned the tube gear I prefered the Ei Kt-90's over either Kt-88, 6550 or El34. Mostly out of reliability issues. Some amps built exlusively around El34 tubes could sound wonderful. Like the older CJ amps.

Dragan (Eldragon) is correct about the reliability of the Ei KT90. They are simply the best in that area. No other current production compares.

If you need the added gusto of the larger tubes, the JJ KT88 are my choice. 6550 tend to sound quite flat and uninteresting to me, as Averageguygeorge called it, "similar to SS amps". The KT88 adds a midbass fatness that I find intoxicating, along with sweet midrange and a nice treble.

Still, I think that overall, if you can get away with them from a power standpoint, the JJ E34L presents a midrange that is so good that you can forget about them not being so great in the lower frequencies.

My experience with the 6550 tube is in agreement with those who find it flat and uninteresting, sure does have nice bass control, however. Hard to beat the sweet midrange of the EL34 although bass is a bit soft. I prefer the SED version of the EL34, this is the original Svetlana EL34. The new Svetlana tube is essentially a Sovtech design.