Even straight out of the bo...x these reissue gold lion kt88 tubes blow away the competition that I've tried. Most kt88 amplifiers nowadays come with psvane and I'm telling you they are sterile tubes and not in a good way, sure they are listenable but you just know it can be a whole lot better, the gold lions are warmer and hands down more detailed and critically they have an open holographic sound that I could never get sick of, this is what tube amps are meant for in this day. The psvane also seems to have inconsistent bias where the GL holds dead where you set them. I can't recommend them enough. I first tried a few of the "cheaper" nos kt88 and 6550 that I was able to get but with all of the praise the reissue gold lions receive I knew I had to try them. There are some nos tubes of this type that sound pretty good but you don't know how much life they actually have in them and usually they are bought as is due to being vintage and definitely no guarantee, these have a 90 day warranty! I'll admit I haven't tried the nos gold lions but I'd never spend the money they go for so it's irrelevant to me but out of the nos stuff I have tried I haven't heard my amplifier come to life like this. The gold lions have that romantic quality we want in a tube, like most of the nos stuff I've tried but where the gold lion kt88 pulls ahead of the nos is with the huge holographic sound. If your hesitant to part with the cash allow me to make it easier, if I could go back I'd save the money I spent trying out all of the others and go straight to the gold lion and never look back! Only way to describe these is stunning, that is it!
Verified purchase: No
Very well made and packed with a corrugated cardboar...d sleeve inside the tube box. The tube feels heavy and solid in your hand. The bias remains steady when you set it after the initial warm-up period. The matching by Tonal Tubes was as good as it can get, much better than the standard Russian 24 hour burn in and matching alone. I checked the Tonal Tubes matching on my custom tube matcher (see picture), and the four tubes were all within plus/minus 2 mA of 52 mA with 428 volts on the plates and -48 volts of bias. Screen current was very well matched at 6 mA each on all four tubes (a testament to manufacturing grid alignment consistency). The sound is wonderfully warm top to bottom with a deep and wide soundstage, of course some of this depends on your amplifier too.
Verified purchase: Yes | Condition: New
These tubes are far better than the PrimaLuna factory tubes in t...he Prologue Five, way better base, treble isn't bright, it's right, no muting of details, and the mids are great as well, top to bottom better. Better air, space/soundstage. They aren't even broken in yet. I have nominal experience with power tubes, but these sound like a great SS amp with a shade more tube sound.
Verified purchase: Yes | Condition: New
This tube is my favorite of all the "ne...w issue" (as opposed to "NOS") tubes I have tried in my limited experience with power tubes. It's close to the solid low end and balance of my JJ 6L6GC, better midrange and treble than the Tung Sol EL34B (though not quite as articulate) and much better in my set up and musical tastes than the Gold Lion KT88 I tried for a while. The GL KT77 does it all for me! YMMV as always. Update: Just noticed the heading says "KT88/6550" however, this review is about the GL KT-77. Not sure how I messed that up!
Verified purchase: Yes
I was skeptical, excited, impatient, etc. But these tubes after ab...out 45 min blew my Tung_Sol KT120s out of the swamp. Very nice mid range and after a week The Boss' Nebraska sounded like it was being recorded in the house. Great value. Very good upgrade.
Verified purchase: Yes | Condition: New