Ruby el34s sound flat?

Give them some time then reevaluate.Just a thought.

I've found the Tesla tubes to be more musical than the Ruby EL34.But you really can't tell if they're not broken in enough.♫

Ruby doesn't make tubes, they rebrand them like most of the sellers do. They would benefit from a good outgassing burn-in, especially if they are Chinese. Leave the amp on for 24 hours.

Any Ruby I had was Chinese.Sino?

I can't speak for the Rubys. I'm currently using JJ E34L (not to be confused with JJ EL34, they are not the same tube) in my Quicksilver Silver Sixties with the Gallo 3.1's and they sound excellent. Quicksilver recommends the JJ E34L as a replacement in the Silver Sixties. They sounded good right out of the box. If you don't hear a marked improvement after 40-50 hours I would try something else or you can give Mike Sanders a call at Quicksilver. He has always been very helpful.

They need time...........be patient.

Ruby's are okay depending on the circuit. I would simply use a quad of EH EL34's. The slim one's. I have had some manufacturing buddies tell me they don't like the Fat Boys as much. The EH's have an extended top end and an articulate midrange.
I have a modified Dynaco ST 70 and the EH's are my tube of choice for that amp. I have tried Sovteks, JJ's, and I have a Quad of Teslas but they are the newer vintage and are almost equal to the EH's. By the way I purchase my EH EL34's exclusively from Jim McShane. I tried several other vendors but I'm happy with what I get from him.

Most importantly is that I have a pair of Mullard Reissues brand new with about 20+ hours on them which went in the Dyna first. I thought they were too soft sounding. I bought a pair of EH's to compare and what I got was a sigh of relief. The sound was more effortless than any of the other tubes I tried. I like the warm sound but I also want detail and articulation. I don't like that warm sound with my Spica TC60's.

I have a pair of Quicksilver 8417's that were modified for KT88, 6550's, etc. I recently found out that I could run EL34's in it. I put in the Mullards at first and they were pretty darn good. But when I put the EH's in there it I got a smoother and more articulate sound. More transparency if I must say.

I have a friend that bought several quads of NOS tubes and they were wonderful but when one went up smoke glowing red he was hurt and finding a match was a chore. I told him to buy a pair of EH's and he did and he was very impressed. He wanted buy a Quad of Gold Lions. But I told him he could buy 3 Matched Quads of EH's for the same money. The EH's sound was at least 95% of the gold lions. His amps were a pair of VTL monoblocks and A quicksilver GLA. Until I find something that betters the EH EL34/6CA7's I'm sticking with them. None of the other recent vintage tubes are as articulate in either of my amps the Quicksilver 8417's or my Dynaco ST70. Plus the EH's are comparable to the Ruby's in cost. Give them a listen.

I thought the Teslas (JJ) were really sweet in my mini-monos. I have tried some KT88s but I went right back to the Teslas, I don't think I'll be looking for anything else, I'm way happy with the Teslas.

Thanx, Russ

Thanks for all of the responses. After playing them for about 30 hours I have grown to like them. The bass is definitely better than the Teslas ( more and tighter) but sound stage a little smaller and upper treble a bit muted but all in all very musical. I may try EHs next based on what I have heard.

I realize this is a very old post but I put some late 60's NOS Mullard EL34's in my Quicksilver Mid mono's that had the stock Tesla's in it.  There have been a few things that have got my attention when trying out new "so called" improvements to my system.  This was one of those "holy @#&*%" moments when I thought the price of those tubes was well worth it.  A VAST improvement.

Listed below is a link (Compares New production EL34 Tubes)  that may be helpful with your selection process.
http://wallofsound.ca/audioreviews/tubes/el34-tube-comparison-with-tubes-supplied-by-www-thetubestor...
Also some further research on the new black diamond Telefunken, Psvane EL34 types, including the Black Treasures (see Grant Fidelity), and the Sophia EL34S (coke Bottle) may be of value to you.
As rsfphl stated, I also have found the JJ E34L to be an exceptional tube; Its a very high value tube. a quad can be found or approx. $65.00 per quad.

I agree with the results of that comparison the Gold Lion KT-77 is a flat out great sounding tube and good value I've been getting matched burned in quads from Tonal Tubes for $170 and free shipping. Beat the pants off the JJ 6ca7 and Winged C EL34s and PSvane Phillips EL34 replicas in my system my amp is a Deja Vu stereo pushpull wired in triode class A.