Tube amps and speaker ohms

I think the point Newbee made about the EL34 versus KT88/6550/KT90 is something that REALLY needs to be lauded. EXCELLENT POINT!!!

The EL34 is a tube that is going to be in many of these amplifiers. And, while it is my favorite of the traditional push-pull amplifier tubes, it does has its shortcomings. As Newbee pointed out, you are going to give up those low frequencies (and overall power) in exchange for those wonderful mids. Please be aware of this.

Another tube to consider is the KT77 made by JJ. VERY powerful bass, and good power overall. You still don't match those EL34 mids. Consider it a great tube slotting between the EL34 and the KT88. In more than a few amps, we actually heard MORE emphatic bass with the KT77 than the bigger tubes, combined with some seriously better midrange.

Tvad - FWIW, dealing with like kinds, ie SED's, I found the 6l6GC slightly mellow thru the upper mids/highs compared to the EL34 in both of my Primaluna amps which were primarily designed around the EL34 or the KT88 and to my ears both sound best with that the tube around which it was designed. I've been sort of interested in hearing an amp designed around 6L6's but I haven't found one yet. I tried them in my Baron but they were to hot - I'd have to get it modded (it takes 5881's).

JJ is the only maker of KT77's right now that I'm aware of. On AA several posters have been high on the sound they make, but there is some strong comments on quality control and pin size. FWIW - you probably already knew that.

Grant, my KT77 comments are based solely on listening to the JJ variant. I'm not sure how the Osram (didn't know they made KT77) and Mullards would sound.

In my Jadis DA60 and Dennis' (Badboss429) Quicksilver, a bunch of us (including Mechans) compared the JJ E34L blue glass, JJ KT77, vintage 1960s Mullard EL34 XF1 (EL34 Holy Grail), and JJ KT88 blue glass. The KT88 came in last. The rest of the tubes had a variety of opinions. Overall, things seemed to split between the Mullard and JJ E34L, but many of us couldn't get past the powerful, intoxicating lows of the JJ KT77.

From what I heard, the first batch of KT77 had issues with the tube pins. The octet I bought in January/February 20076 had this issue corrected. Didn't have any fail, either, but it's a complaint many have put forth with JJ power tubes in general. I have an octet of E34L Blue Glass, and one day while measuring them about three weeks ago, I found one was as dead as a doornail. That came as kind of a shock.