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Hi Maurice, For current production, I've had good luck with the EH 6922. I use a pair in my EE Minimax CDP, a quad in my Counterpoint SA-100, and had them in an Anthem Pre-2L that I sold. In the affordable range, but not current production, I also like the JAN 6DJ8 variously branded Philips, GTE, Sylvania from the early 1980's. The 6922 is a more "rugged" version of the 6DJ8 (designed to operate at a max plate voltage of nearly double the 6DJ8.) In a single tube stage circuit, the JAN 6DJ8 might just sound a bit more musical to you. I'm not familiar with your SET preamp. Does it utilize tube rectification as well? If so, IMO, the rectifier can be quite important in achieving the SQ you're after. Mike

Thanks! They (the ST-70 and DCM) are two pretty different takes on the 4 x EL34 circuit. I think an ST-70 with power supply cap upgrades and a driver circuit with 3 or 4 12A(insert your favorite letter here)7's would probably be really close. I'll very likely mod the ST-70 along those lines in the future - due to the dwindling supply of good 7199's and a desire be rid of the selenium rectifier and for better power supply capacitance. The DCM is my favorite of the two, a gorgeous sounding amp.

---------------- On 2/22/2005 11:45:12 PM sputnik wrote: Dang! Now I'll be humming it all night. ---------------- LOL! I know the feeling. Uncle Kracker did a respectable cover of that tune with Dobie.

Hi Maurice, We've chatted about this in another forum (where tube lovers are a bit scarce.) It's nice to see all the fellow tube junkies here. I have two tube amplifiers - A Dynaco ST-70 (which is stock, save for cap upgrades on the driver board), and a David C. Manley 75+75 (4 x EL34/6CA7 not tube rectified.) I variously drive RF-3's or Polk SDA-SRS's with my gear. So far, here are the rankings from EL34/6CA7 types I've tried: 1. JJ/Tesla E34L - Really bring out the best in my ST-70. Bass is tight and extended with real punch. Clear mids with exceptional definition and imaging. Highs are shimmering and vibrant without harshness or grain. They took aprox. 30 hours to burn in and open up. I haven't tried this tube in the DCM yet. 2. (Actually, tied for first)Vintage mixed quad of Sylvania/Dynaco/Mullard (all identical build structure) - In the ST-70 they have a warm and buttery mid range, yet not to the extent of detail loss. Bass is strong, but a bit loose. Highs roll off a bit early. In the DCM they are about all you could ask for. Makes you feel like part of a live musical experience. 3. Ei thin bottle pinch top EL34 - Second best imaging tube I've tried in the DCM, but quite thin in the bass and not much depth to the soundstage until broken in. The Ei brand is well regarded in current Manley designs, so thought I'd give them a spin. At about 36 hours these tubes started to sound great. One problem - one of them started arcing on the cathode riser to the beat of the music in play. It didn't effect SQ at all (surprising), but it was obvious the tube was destined for a short life. I returned the quad for replacement. The new quad had about 10 minutes on it when one of the tubes blew (literally), even breaking the glass sleeve. Back they went. Quad Three: (Sounds like a boxing match) After approx. 40 hours of play, they're still all in one piece and sounding good (like quad one after similar play time) in the DCM. With fingers crossed, I'm planning to roll them into the ST-70 this weekend. I've heard of reliability problems with some of the Ei small signal tubes. I don't know if it's mu (ha ha that was a typo on "my", but fitting) bad luck or if this may become an issue with their power tubes. Tubes I'd like to try are the "Seimans" branded EL34's - the ones made in E. Germany before unification and disappearance of the factory. I'd be interested in anyone's experiences with these. Closing thought: Has anyone else had the thought that the tube rectified B+ voltage in many vintage amps may be a bit high for some current production EL34 types? Some of the tube data I've read leads me to believe the new production types might fare better (both in longivity and SQ) in a tube rectified circuit with something like a GZ37/CV378 and a 10-20 volt drop in B+. Crazy idea? BTW - this is my first post here, so be gentle. Mike