Breaking in Genelax Gold Lion KT66s

Pez · « **on:** 31 Jul 2009, 06:03 am »

Just sprung for an Octet of KT66 Gold Lions after Tyson was kind enough to let me borrow his for a few weeks. These are a beefy looking tube. They feel substantial and very well made. Every detail of the look screams "Attention to detail". (for system details see my sig)

I was incredibly impressed at how much better they were than any EL34's I had used. I have an Octet of Winged =C= on the Radii DPP-105 (I know I know, you've never heard of it

) most of the time as I have heard nothing better I have tried JJ EL34s, E34ls, Svetlana EL34s, Electro Harmonix, and various labeless Sino EL34s. when I heard the GLs I was blown away by there big fat presentation. But now that I have them brand new I get to break them in on my equipment. Here's a log to give you an idea how these puppies break in. I will not be able to comment on the bass as I have them setup so they are running the ribbon section only on my RM40s which really frees up the Radii to retrieve every ounce of detail it can in the midrange and highs.

Out of the box: The GLs are deceptively good sounding right off the bat. Rough around the edges and there's a certain whiz bang quality about the sound that definitely catches your attention but ultimately is the reason I hate most solid state equipment. A lot of "Wow!" factor, but no inner detail, no control over sibilance. Cymbals etc sound very artificial, as well as quite a bit of congestion from vocalists, and certainly nothing that pulls you deep into believing the illusion. All that said you certainly can hear the potential of these tubes right off the bat and they are the least offensive tube I have heard out of the box.

15 hours: Welcome to break in hell. Nasal, chesty, FORWARD presentation, craptastic treble control, bright BRIGHT BRIGHT and probably the most out of focus soundstage I have ever heard from two identical speakers hooked up to the same amp.

Forget it, all the nice things I said about them out of the box were wrong, send these back to the the store they are broken...

30 hours:

One redeeming factor, they are no longer bright, just chesty, slightly less foward, no improvement to out of focus soundstage, slight hint of inner detail, but that could just be wishful thinking on my part. Why are vocals that are supposed to be center floating from left of center to right of center then evaporating into thin air? Why is piano sounding like it's constantly overloading the mic? Dynamics are either really soft or shouty.

I know this probably isn't helping anyone yet, but I have heard the true capability of these tubes. I can't wait to get to that point to share my findings. I will compare them directly to the EL34 JJs and the Winged =C=. More to come.

Angaria · « **Reply #1 on:** 31 Jul 2009, 09:28 pm »

Very interested in how this progresses as I'm interested in picking up a quad. Based on my last set of Tesla's I'd say wait for 100hrs before final judgement. (just what you want to hear, I know)

Pez · « **Reply #2 on:** 31 Jul 2009, 10:11 pm »

Actually estimates I've read go anywhere from 100 to 300 hours. I am letting them run 24 hours a day with a computer fan on full blast just in case. Don't want things to get too toasty in the wood furniture they're sitting in. So far they are very stable and the bias seems to stay put rather well. Today I will have about 60+ hours so I'm either half way or 1/6th depending on who you ask.

rajacat · « **Reply #3 on:** 31 Jul 2009, 10:55 pm »

I had have a quartet of Genelax Gold Lion KT66s in my Heathkit W5m monoblocks for about 3 months.
Previously I had Valve Art Shuguang Chinese KT66s but one had a premature failure so I decided to try a different tube. Yes, they did sound rather good from the beginning but they seemed to mellow out after a number of hours (100?) and attain more gravitas. As usual I didn't monitor the hours closely so I can't say exactly when they reached maturity but I'm very satisfied with their performance. I'm constantly tweaking my rig so often I have an overlap that interferes with attaining and objective assessment

. Nevertheless, I certainly can recommend the GL KT66s.

I do prefer them to the Chinese KT66s which may have reliability issues and do not seem to image as well or have as large of a sound field.

-Roy

Pez · « **Reply #4 on:** 1 Aug 2009, 05:49 am »

50-60 hours Ok now the sound has really mellowed. No longer spitty and chesty. Soundstage has snapped into focus much better, though not quite where I want it to be. Sweet spot is still small and somewhat shifty definitely not up to par with where the winged =C=s are in this respect. There is still a bit of sibilance, though nothing near the horrors I heard at 15 hours. They are starting to show hints on nuance, but still lack the refinement to be convincing about it. Dynamics are much improved showing much more shading than previously, again not quite there yet.

It's getting close. By the end of the weekend I'll be at 100 hours. Hopefully they will stabilize! Only 40 or so hours to go.

Pez · « **Reply #5 on:** 2 Aug 2009, 04:58 am »

70-80 hours: ok doing some critical listening at 70 hours was interesting, things have taken a turn, the sound temporarily turned to mush. No definition and bloat in the mids and a rather nasty top end, but at 80 hours everything seemed to snap into place. Sounding better than the EL34s (based on memory). Much better soundstage and vocals are now focused rather than floaty. Things are starting to sound consistently good now, getting close!

Pez · « **Reply #6 on:** 3 Aug 2009, 05:14 am »

90-100 hours. Nice solid sound! It still feels a bit shouty and higher volumes, but I think that's a microphonic issue and I've got some dampers on the way to take care of the problem. Detail is phenomenal, dynamics are the best I've heard from my system and everything sounds so natural and realistic. I am very pleased with what I'm hearing now. I'm not 100% sure they are completely broken in yet. I'll let them run again for 10-15+ hours and listen again, but it's hard to imagine it getting much better! Next step after I'm sure they are ready is a direct comparison to the Winged =C=. It may be a week or two before I can really get going on this so bare with!

Angaria · « **Reply #7 on:** 31 Aug 2009, 01:31 am »

We'll see if my experience mirrors yours. Just swapped in the GL's for the tungsol 6l6gc-str's that'd I'd been running (22wpc PP integrated).

Current impression of the GL's are very dry bass, congested and uptight sounding midrange, detailed but shrieky highs. I'll update around 30 hrs or so.

Pez · « **Reply #8 on:** 31 Aug 2009, 01:46 am »

I never finished updating. I'm well past the 200 hour mark. If I had to pick an hour in which I think they were done I'd say about 130. The overall sound is very liquid. Much more so than my shugang 88s or EH 88s. Very similar to the winged C el34s but much more refined and definatly has a deeper sound stage and much better highs. I tried them against the GL kt88s for a bit last weekend and liked them bettter for their liquidity, but lacking a bit in comparison in 3d soundstage and overall detail. Still an excellent and under rated tube I have switched amps to the Bella since I started this thread and have yet to find a tube that was definitively better! I have penta KT88s on the way so we'll see.

jcspinks · « **Reply #9 on:** 31 Aug 2009, 02:01 am »

Do check out the Shuguang Treasure / Genelex GL thread. My Treasure 6ca7s are mesmerizing after 300(!) hours of break in.

Pez · « **Reply #10 on:** 31 Aug 2009, 03:14 am »

Oh believe me. If I had that kind of cash to throw around I'd definately buy a quad of the 88 black bottles. They are high on my must have, but can't afford list.

Angaria · « **Reply #11 on:** 7 Sep 2009, 04:34 am »

Would just like to confirm similar progression to Pez, though in my case I felt it was a steady improvement of bloom and bass extension. But was it worth $100 over my previous tungsols? In this amp perhaps not. For comparison, found a similar margin of improvement going from nec 12ax7's to rca blackplate 12bh7a's in this same amp.

Pez · « **Reply #12 on:** 7 Sep 2009, 04:47 am »

Yeah, while they are great tubes, I to have moved on to a different set that is better. The Penta KT88s, but I will say that if you have an amp that can only run el34s or 66s these are the way to go for sure. IME.

JakeJ · « **Reply #13 on:** 7 Sep 2009, 04:21 pm »

Hi Pez,

So you are now running the KT 88 and before you were running the KT66? Isn't that kinda like comparing an apple to an orange? Not trying to be negative here as the run in chronology is good info but it seems that a more definitive comparison would be using same tube types of different brands. Penta KT88 vs. GL KT88 or the various brands of EL34 you mentioned to each other.

Since the KT 88, KT66, and EL34 each have different plate voltage and current ratings it seems a bit of a conundrum, eh?

BR,
JakeJ

Pez · « **Reply #14 on:** 7 Sep 2009, 04:37 pm »

Yes indeed, apples and oranges. I am actually planning on putting the pentas up against my buddies gl kt88s fo comparison. However as far as Kt66s and el34s the gold lions ARE the best I have heard without a doubt. I have tried JJs I have tried Svetlanas, winged c, EH, and quite a few unmetionable ones. Heck I'd use the GL 66s before some KT88s that I have like EH and Shugaung standard issues if you really want to throw a wrench in things. I have not tried them vs any other KT66s. So there you go, for whatever that's worth

Quote from: JakeJ on 7 Sep 2009, 04:21 pm

Hi Pez,

So you are now running the KT 88 and before you were running the KT66? Isn't that kinda like comparing an apple to an orange? Not trying to be negative here as the run in chronology is good info but it seems that a more definitive comparison would be using same tube types of different brands. Penta KT88 vs. GL KT88 or the various brands of EL34 you mentioned to each other.

Since the KT 88, KT66, and EL34 each have different plate voltage and current ratings it seems a bit of a conundrum, eh?

BR,
JakeJ

JakeJ · « **Reply #15 on:** 7 Sep 2009, 05:25 pm »

I think the info you provide has good value but one must remember that your findings are for your amplifier and we may get differing results in our amps. Of course anyone familiar with tube gear is most likely going to be aware of that.

Out of curiosity I did a Google search for the Radii-DPP105 and only three links came up. One was to your review here on AC (that link no longer works, BTW), and a link to TNT audio for the AK Fest with Wayne Waananen, and posts on AA. However there is a link within your for sale ad to the Radii website which is here in case anyone else is curious. Unfortunately there isn't much info about the circuit, such as plate voltages, etc.

The website also does not make mention of running different tube types in the DPP-105. Is this something that Wayne had customized for this particular amp?

I will say again thanks to Pez for making these comparisons as I am currently in the market for tubes for my VAC PA-160 monoblocks and there are so many choices it does confound things a bit. Guess I'll need to do something similar by buying a few different brands of the tubes I need and make my own comparisons.

BR,
JakeJ

Pez · « **Reply #16 on:** 7 Sep 2009, 05:37 pm »

the type of equipment will make a difference, BUT I have never heard a bad tube suddenly sound great on a different amp.

that said you are correct sometimes it is system dependent.

As far as the kt66s I asked the designer directly and he said 'no problem' running 66s. Any other info would have to go through Santaman of Radii.

Tyson · « **Reply #17 on:** 7 Sep 2009, 08:07 pm »

The GL KT66's are smoother than the GL KT88's, but the 66's lack the dynamic punch and soundstaging abilities of the 88's. What to do? Well, I run the 88's on my midrange, and the 66's on my tweeters (and a monster Solid State amp on my bass woofers). Now that I've got a decent tweeter in my speakers, the sound is pretty phenomenal. That said, Jason is bringing his Shuggie KT88's over, which are supposed to be the "best of both worlds", should be fun!

JakeJ · « **Reply #18 on:** 7 Sep 2009, 09:12 pm »

Please post your opinions after your comparisons.

Thanks,
JakeJ

Tyson · « **Reply #19 on:** 8 Sep 2009, 04:56 am »

We tried the Shuggie KT88's in my treble amp and they were as smooth as the KT66's, while having a lower noise floor (ie, there were more spatial queues and ambient information presented), and matched the Gold Lion KT88's in tone and dynamics. Overall I'd say they were very nice tubes indeed.

We also listened briefly to the Gold Lion KT77's. I think they are not a great match in my amps and with my system. I'll probably sell my octet before long.