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MF MD HG01 2017 Holiday Gift Guide 11-12-17
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210099 000118185

Tung-Sol KT66 Matched Power Tubes Medium Duet

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Tungsol KT66 Power Tubes mean that the Bluesbreaker sound is back--woman tone at its finest!The platinum matching process consists of a 24 hour tube...Click To Read More About This Product

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Tungsol KT66 Power Tubes mean that the Bluesbreaker sound is back--woman tone at its finest!

The platinum matching process consists of a 24 hour tube burn-in period followed by a bias (plate) current measurement in milliamps.

Order tubes BEFORE they need to be replaced, and save the gig.


Review Snapshot

by PowerReviews
Tung-SolKT66 Matched Power Tubes

(based on 3 reviews)

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Reviewed by 3 customers

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(7 of 7 customers found this review helpful)


Just the facts

By Marco

from Baltimore

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Comments about Tung-Sol KT66 Matched Power Tubes:

I bought a matched pair of these from MF for a Marshall Vintage Modern i got last month and im glad i did. These are a great sounding, powerful tube, gainy and very midrange forward, which is i suppose, the only reason to use KT66 tubes in a guitar amp. Ive seen much sneering and jeering of these tubes on various amp forums, but here are the facts.Marshall has used EL34 tubes for over 40 years for a reason: The original KT66 was unpopular with guitar players (before Eric Clapton used them and they became legendary) because it was expensive, scarce and when Marshall started using them in 100 watt high gain amps, they had a tendency to burn out like Chinese made light bulbs.Speaking of Chinese made light bulbs the Shaugang KT66 is very popular on many of these same amp forums. Since thats what was in the amp when i got it i have some experience with these too and can compare. The Shaugang LOOKS a whole lot like an old British made GEC KT66. Apparently from what ive seen in the forums,some of the supernatural,magical characteristics of old tubes suffuse a new Chinese made tube if the glass is the right shape. Thats the only reason i can think of for the praise heaped on the Shaugang.According to the spec published by GEC, an original GEC KT66 in push pull operation used about 450-500 plate volts,450 screen volts, drew 70-80 mA current and put out 25-30 watts per tube. Those are the published specs of this Tungsol tube. I have some knobs and electrical probes just like the amp forum guys and i can tell you the published specs are accurate.Perhaps they arent Magical but maybe Tungsol/New Sensor can change the shape of the glass envelope to let the magic NOS tube spirits in......... Features (its got all of them) 5, Quality (compared to other New Built)-5, Value (compared to other KT66) 5, so overall it has to be a - 5.

(4 of 4 customers found this review helpful)


Excellent KT-66

By Guy-nv9XO

from Me.

See all my reviews

Comments about Tung-Sol KT66 Matched Power Tubes:

This is my new favorite KT-66, replacing the "Gold Lion" reissue. This is an extremely rugged and well built tube.Very high quality material and American engineering from New Sensor. Sounds more like a fine 6L6 than any KT-66 ive heard. I also want to dispel some nonsense ive seen on Marshall forums:this is NOT, in any way, a "relabled" 6550 or KT88. Electrically those are both very different tubes. Also, this tube can be used anywhere any other KT-66 can be used. Make sure to insulate the METAL BASE if you have the "bear trap" tube retainer clips,(Vintage modern owners im talking to you) so it doesn't ground to the chassis. Just thought id mention that before i read another sob story about how this tube is really a 6550 and it "ruined my amp'- nonsense.


Best tube for a Valve King 112 !!!

By Lucky Man

from Bluegrass State

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Comments about Tung-Sol KT66 Matched Power Tubes:

Simply said, If you have a Valve King 112...this is your tube!!!Plug and Play once you remove the "cage " and the'll not use them for this tube due to "grounding" issues on the metal base,,,get some spring retainers if you feel the need...Enjoy!!!

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