Genalex - Gold Lion KT77 Power Vacuum Tube (Matched)

19 Reviews

Availability: Usually ships within 24 hours.

USD $‎81.95

Need matched power tubes? Don't worry! Price includes matching in any quantity you need for no extra charge. Need a matched pair? Just order "2" tubes. For a matched quad order "4" tubes. Matched sextets and octets are available as well.

After extensive research and engineering, New Sensor Corp. has reissued the famed Genalex Gold Lion KT77 vacuum tube. This tube has been recreated down to the finest detail for exceptional performance and sound quality.

For audiophiles, the Genalex/Gold Lion KT77 power tubes have full, yet tight and dynamic lows. They have great clarity in the mid-range as well, and extended highs. Many audiophiles that have previously enjoyed the Winged "C"/SED EL34 tubes have reported that these KT77 tubes are noticeably better.

From our review in guitar amps: "The Gold Lion KT77 is a drop in replacement for an EL34 or 6CA7. The sound however is not typical of an EL34 or 6CA7. It is more of a hybrid. The tube delivers all the mid punch you would expect in an EL34 but also has a top end that is more open and bright. It’s definitely got a bit of a 6L6 designed into it. I tested it in Marshall 2205 50w head and was able to get that 70’s rock sound but with some bias adjustment could also dial in a VOX-like chime."

If you are curious about how these fare in a hifi stereo amplifier be sure to read the Wall of Sound EL34 tube comparison for details.

Other Genalex - Gold Lion tubesEL34 Tube Types

Additional Information and Downloads

EL34 Tube Review for Guitar Amplifiers
EL34 Tube Review for HiFi Audio

Tube Matching Information:
Power Tube Matching FAQ
Perfect Pair System

Genalex - Gold Lion KT77 Datasheet (PDF)

Download Adobe Acrobat PDF reader

Warranty Information and Return Policy

Warranty Period: 3 months

All our tubes are guaranteed for 3 months from the date of purchase. (Any exceptions will be noted on that tube's Warranty tab)

If you receive a tube that does not perform to the manufacturer's specifications, please do the following:

- contact us to get a return authorization
- return it via regular mail within 90 days from when we shipped it, and we will provide an exchange or refund of the full purchase price of the tube.

Returns not related to warranty or defect will be considered at our discretion, and are subject to a 15% restocking fee.

We can not accept returns that don't have an authorization, are past 3 month, or are returned improperly.

These guidelines may be updated without notice.

Ratings & Reviews

19 reviews

Genalex - Gold Lion KT77 | impressed


On my Marshall jcm 2000 dsl 50...I have been using EL34 Mullard; then preferred em..when i bias em, it's set at about 40.4...well i was readin about the i gave it a shot...set it @40.4; (50 watt amp range 25-42) wasn't happy...too hot yew...on the box they were set at i lowered em down 30.1...unbelievable; jaw went to the ground....a fractual audio axe fx into the clean channel of the jcm....everything just rings out from clean to driven....

Genalex - Gold Lion KT77 | Golden Lion!


I replaced the el34 s in my melody integrated amplifier. This was after I replaced the preamp tubes and finally I had an amp that I could listen to. Extended top and bottom with proper tonal balance. The detail got better as well as strings and voice sounded more lifelike. These are far better that the stock tubes that came from the factory with this amp. Looking at buying a set of 16 GL-KT77 for the mono blocks.

Genalex - Gold Lion KT77 | Didn't last long.


I must report that after about 10hrs of use the tone changed for the worst. Initially the GL-KT77 sounded wonderful, but now the tone emphasis has shifted all to the mids, and to make matters worst, taking my amp off standby creates a loud *crack*, and sparks of current can be seen around the switch's periphery. I replaced my standby switch in vain as the problem still remained, replaced the GL 77s with the previous tubes and the problems vanished.

Note from The Gold Lion tubes have a 90 day warranty. Contact us for replacement.

Genalex - Gold Lion KT77 | Current King of big bottle guitar tone


These GL-KT77 sound massively awesome in any British style guitar amp I've tried to date - and yes, Winged =C= are to beat for classic EL34 but these are the superior athlete, respectively. Bigger, deeper, higher, punchier, richer in every measure and yet there's a definite sophisticated quality that reminds me of the maturity, laid back attitude of NOS tubes. Frankly, these are the current big bottle tubes to beat. Pricier, but still way more practical than spending hundreds more for vintage tubes which is hard to justify

Genalex - Gold Lion KT77 | Unreliable


Failed after about 300 hours. Sounded ok, but only ok. Not worth the money IMO