Tung-Sol KT120
New Sensor now announces the Tung-Sol KT120, which has a plate dissipation of 60 watts, making it the most powerful tube in the 6550/KT88/KT90 family. A pair of these tubes in push-pull configuration can deliver power levels of 150 or more watts. When used at the parameters found in existing 6550/KT88/KT90 circuits, the Tung-Sol KT120 is impervious to overload, delivering peak power with extreme reliability and long tube life. However, taking advantage of the higher current handling capacity of these tubes, a very unique and super powerful and stable amp can be designed using the Tung-Sol KT-120.
Note: The size of the Tungsol KT-120 tube is substantially more than its KT88 cousin. The seated height is approximately 4.5" (113mm). The width is 2" (52mm).
Other Tung-Sol tubes 
KT88 Tube TypesAdditional Information and Downloads
Tube Matching Information:
Power Tube Matching FAQ
Perfect Pair System
Downloads:
Tung-Sol KT120 Datasheet (PDF)
Download Adobe Acrobat PDF reader
Warranty Information and Return Policy
Warranty Period: 3 monthsAll 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
11 reviews
KT 120... A new BENCHMARK
by Nigel
After reading on Prima Luna.com the U.S. website that an announcement has been made that after many months of testing"It is safe to use Tung Sol KT120 in ALL Prima Luna amplifiers".
My Dialogue 5 power amp can use every major power tube except 300B and EL84, and I have tried many tubes.
Not being a fan of KT88 and using Shuguang Treasure 6CA7-Z for many months, I decided to try this new design.
Out of the box I noticed the bottom end was boomy and sloppy.
So I gave them 50 hours over 3 days giving them 8 hours on and 4 hours off.
I have to say that this tube is seductive and awesome.
I consider it a benchmark of tube design/sound. A decathlon valve of the tube world if you will.
It has the mids of an EL34 and bottom and top end that my Treasures can not come close.
But compared to a KT88 such as the Gold Lion this is where this KT 120 tube takes off.
The bottom end is so much more controlled and the top end soars higher and cleaner.
For the record I consider the KT120 the most musical tube in the 6550, KT88, and KT90 family.
I am totally impressed and every time I listen to my music lately I have had a big smile...Cheers
Ian
by Ian Storey
Just bought the Tung-Sol KT-120 set of 4 for my Prima Luna Pro Logue Premium. I am new to the world of valve amps but these things sound better than great. I replaced the EL34 tubes based on reviews on this this site. Couldn't be happier and thank you heaps Tube Store. This site is very informative - I don't think I'll change valves after these 120s. Just great.
Geat Sounding Tubes
by BobW
I ordered the matched set of 4 Tung-Sol KT120's for my Jolida JD502CRC on Friday 12/27/13 and on Monday 12/30 they arrived(using the "Economy Service" shipping). I now have about 90 hours on them. Compared to the Tung-Sol 6550's that the amp came with - the Tung-Sol KT120's have tight extended Bass, real nice mid-range, and clean extended high frequency, they are very open and not restricted, the KT120's are more musical than the Tung-Sol 6550's. They effortlessly push the amp more than the Tung-Sol 6550's. The amp now sounds exactly the way I have always wanted the amp to sound, it sounds great with 50's, 60's, 70's, and 80's rock music. I am also running thetubestore Preferred Series 7025/12AX7for pre-amp tubes and Mullard CV4024/12AT7WA for driver tubes.
Awesome
by Krish Iyer
I replaced the EL34s for a matched set of Tung-Sol KT120s on my Primaluna Premium Integrated Amplifier and the improvement in the musicality and overall sound quality delivered via my Focal Electra BE1028s has been astounding to say the least. Especially the bass and mid to lower frequencies emerge with a lot more depth, and the overall sonic range is richer and smoother. Can't think of going back to the EL34 tubes!
I was impressed with the speed and quality of delivery and overall service from TheTubeStore, and have placed my order for a standby set as well. One tiny niggle though - I wish TheTubeStore blue sticker were put on the back side of the tube rather than front. It impacts the overall optics. Is that sticker really required?
Note from thetubestore.com: The blue Perfect Pair sticker is attached so the customer always has a record of the tube's matching characteristic in the event a replacement is needed to mate with this set in the future. Regarding the "front" or "back" of the tube, there really is not either. Amp's vary widely in how the tube sockets are mounted. What is the front in one amp will be the back or side in another depending how the socket is mounted.
Convergent Audio Technology/KT 120
by Jim
I had my CAT JL1s modified for the KT-120s because CAT is now using KT120s in their new designs. The KT120 tubes are a major upgrade in sound to the 6550 tubes.