My Rhea's new partner arrives today

Dan,

I can assure you that JD's system does not at all have the digital edge that is prevalent in many other digital-based systems. I believe his Sony unit has gone through a few 3rd-party upgrades so this is not your average Sony unit anyway. The first time I took the Callisto Sig (it had the stock Sovtek tubes at that time) to his home, the sound was not at all forward nor fatiguing.

As for needing to spend a fortune on tubes here, there are many great Mullard and Telefunken pairs out there for less than $100. In fact I have bought quads of these tubes that comes down to $30-40 for each tube and these far exceed the stock Sovtek tubes in terms of resolution, tonal coherency and dynamics. But so far the most quiet 12ax7 I have tried is the Ei and these are only $15-20 a pair! I have 30 or so Tele 12ax7 tubes and none of them are as drop-dead quiet as the Ei's. The Ei's give up a little of the magic to the others in the Callisto & Io but so far, I find them to be the best tube for the Io's input stage. But this is only an issue on the first stage of the Io. I have not played with many Mullards in the Io yet.

JD and another local audiophile were at my home a couple weeks ago and we dropped in a prized pair of BugleBoy 12ax7's in the Callisto. I think we all agreed that the Mullards I had just swapped in replacing the Tele's "locked in" the music like the BugleBoy's had not. With the Mullard, the tonality was more coherent and the sound was more dynamic as well. The Tele's were definitely lacking resolution and presence in the upper frequencies....but I love these things in the Io. You just gotta try each one for yourself in your system.

I just loaned a few pairs to an A'gon member and he ultimately liked the Ei the most in his CAT preamp. If you'd like, I could loan you a pair of the Tele (smooth or ribbed) as well as a pair of Mullard. He ultimately kept the pair of Ei's so I do not have any extra here.

John

Hi John.

I knew I was probably going to get spanked for that "digital edge" comment. :) Guess I was really trying some bogus rationalization technique. Thanks for sharing some of your tube experiments with the IO. As it happens, I do have some of the Ei's. I'll have to give them a try in both the Rhea and Calypso. I checked again and the 6922 that is installed right now in V5 of the Rhea is the JAN-Phillips ($20) as I believe I had read somewhere that a poster had gotten the Rhea a bit quieter using these. I'll have to swap those out with the originals to see if there is much of a difference since I'm guessing I could hear that easier with the Calypso in the path than with the BAT.

I think I have found some Tele's and Amperex 6922's to try in the Calypso. I'll have to keep my eyes open for reasonably priced Mullards to give a listen to. Thanks for the offer to loan some to me, very nice of you. I may take you up on that if I have trouble finding some. As for the Tele's, do you find much difference between the smooth and the ribbed?

That's a nice thing about the Rhea/Calypso combo, and probably the Janus as well. There are several places along the signal path to change the sound abit. Then this number grows even more with the Callisto and Io. The BAT is wonderful, but not much room to tweak should one feel the urge.

Dan,

I have not compared the Tele smooth to the ribbed. Each time I have gotten more Tele's, I have tried them in the Io's input stage hoping they are super quiet like the Ei's, but so far such a quad (or even a pair) of Tele's has not crossed my path. So I have simply replaced the stock tubes with the newly arrived Tele's and enjoyed the improvement with no attention to which type of Tele it is. I guess I will have to do this next time I have an itch to tinker with the tubes. If you are interested, I could loan a pair of each to you.

And one more thing: I have tried the Amperex 6922 in the Callisto and the Io and this tube just does nothing for me. It was lifeless and in fact a bit fatiguing. I always prefered the RAM and Sovtek tubes to this in the ARC LS5 that I ran with for years as well. YMMV. But oh how sweet the Mullard 6922s are in the Callisto and in the CAT amps.

John

Today I'm posting some early Calypso tube rolling results. I tried a pair of Ei 12ax7's but the ones I have just didn't really sound that quiet although they are better than the stock tubes which are a pair of Teslovaks. Next I swapped in Tesla ECC803S. Much, much quieter than both the Ei's and Teslovaks. I have to stick my ear up to the speakers to hear any noise Very good dynamics and decent imaging. A nice improvement but not much different than the Ei, just quieter. Then came a pair of Tung-Sol 12ax7. Just as quiet as the Tesla but the details, dynamics and image resolution are a real big improvement over all of the tubes I've tried so far. The soundstage is deeper with the Tung-Sol. I could be happy with this tube. This combination of the Rhea and Calypso is quieter than with the BAT VK50SE with just changing two tubes. This tube may be a real good candidate for the V1, V2 positions in the Rhea. Still waiting the arrival of the Tele's and Amperex I bought the other day.

As for the 6922, I am trying a Tesla PCC88 but it is too soon to give a decision on them.

>>Dan, I have not compared the Tele smooth to the ribbed<<

I hope the ladies aren't reading this.
:-))