KT77 back in production

[organ]

Thanks to Eurotubes.com and JJ, the famous KT77 is now back in production. Well, not full production yet. It will probably be a few more months until you see it in your favorite tube dealer's website.

For those that don't know, the KT77 is suppose to be the ultimate EL34 replacement.

Here's a quote from JJ about the new KT77.... "A true beam Tetrode for those of you who want to exceed the bounds of a standard EL34".

I'm extremely excited about this. Current production tubes is really moving along. Can't wait to put them up against my KT66.

For more info including pics, thoughts and reviews click on this link... http://www.eurotubes.com/euro-u.htm

Check out the FAT plate!

Maurice

[RuSsMaN]

That's oustanding news.

[madmax]

Awesome!

[BMc]

Rogue sent four KT77 tubes to my dealer stamped with the Rogue logo. They told me the KT77 sounds much better than the EL34's in the Rogue Cronus. I will try them out Tuesday.

[organ]

BMc,
So have you listened to them? I can't wait until they're in full production. I'm getting my quad as soon as they're available. Great amp, btw.

[BMc]

I could not tell much difference on my 3.1TL's. The KT77's may not be quite as bright as the SL34's. The hights seem to be rolled off and the bass is weaker with either tube when compared with my old NAD 7140 solid state amp. With either tube the Crounus could not play at a loud level when my Dish 811 HD receiver was used as a source. The dealer wants me to add a line amp to help the Cronus drive the Dish 811. The NAD 502 CD player was not a problem for the Cronus.

The Cronus is a gorgeous piece of equipment, very heavy and well built. Even the remote is a work of art.

[organ]

Thanks for the update. Yeah, the output signal from the dish might be too weak for the Cronus or there could be an impedance mis-match. If you have a spare pre amp you could try running the signal through that before your Cronus for a little boost.

What speakers are you running? I find that using the 4 Ohm taps on my amplifier sounds best with all my speakers. When matching tube output taps to speakers, go by the speaker's minimum impedance rating instead of nominal. Your bass should increase with much better control on the lower imp tap.

[BMc]

I'm using the Polk SDA SRS 3.1 TL's that I upgraded with the RD0198-1 tweeters. Polk lists these as 8 Ohms. With the tweeters replaced the speakers are not excessively bright and do not need a "warm" sounding amp to tone down the highs.

It's too bad the Cronus does come with spare binding posts or a switch for the 4 Ohms output like my NAD amp. The dealer would rather I ask them take the cover off the demo model and move the wires for the 4 Ohms output if I want to try it that way. I might try the amp again with the Svetlana EL34's in the 4 Ohm setting, and in the correct polarity this time.

I only heard the Svetlana EL34's in reverse polarity. The binding posts were labeled wrong. It caused the SDA drivers to not work. Mark O'brian said I had a "special" reverse polarity unit made for a magazine review.

[organ]

Kick ass rig!!!!

Yes, Polk listed the SDA as 8 Ohms but I'm sure it dips down to 4 or maybe lower. Can anybody confirm this?

Which Svetlana do you own? SED (with flying =C= logo) or the S logo? The =C= is one awesome tube.

[BMc]

I have not bought the Cronus yet. They let me take it home to try it out first with the stock Svetlana EL34's. Two weeks later they asked me to demo it with the JJ KT77's. I did not get a good close up photo of the EL34 and cannot tell you which one it was.

Another look at the KT77 attached.

[organ]

Thanks for the close up shot. That's one sweet looking tube. Can't wait for a quad of KT77 to pump music in my system.

So have you decided if you're buying the Cronus yet? If you feel you still need more slam you can look at amps using KT88.