KT66 amp tubes in action!!!

[clayton5150]

are kt66 interchangeable with 6l6s iv seen pic of 2 6l6s and kt66s in a 5150. the only thing iv heard that could be a problem is heater current.

[dsl100stack]

whoa bro!! your tubes are red plating!

[Progneta]

Its been a while since I have seen a tube light up like that

[drlucaselliot]

search "emitron KT66" on ebay. theres a RARE MINT NOS 1950's pair

[drSwan77]

Oh man I envy that sound but isn´t that a Bryan Adams riff? Let´s just hope he stole it from AC/DC :) No disrespect to mr Adams but he seems more like a Vox-guy to me. Vox rock in their own kind of way.

[EuphorbusBTB]

Whats the American abreviation for KT66?

[MrRhoads26]

The 6L6GC

[rw5791]

kt88's work well with 525 volts and about 60 ma.Kt66 is best around 450 with 40 to 45 ma.

[knowitallhendrix]

Jimi hendrix's favourite JTM45/100W had high plate voltages over 500V. it is said that is what gave him that famous tone, and why he had 1 or 2 amps he liked out of all his marshals

[OneStoneAudioPhysics]

Congratulations...you are melting your screen grids....

[ACDCG400]

exactly. you can run those plate voltages just lower the screens. =[ they're like dying.

[SenorCarrot]

You do realise KT66s are only spec'd to be able to take 500v?

[pgahiwatt]

I have an Australian made WASP from the 60's-70's which runs GEC KT88's as standard(4 of) it produces 280 watts and is bloody loud.The valves/tubes NEVER glow like that and runs high plate votages.I think this amp is in pain!The only other time i've seen this is when i was demoing an Ampeg(also KT 88's)and couldn't work out why there was no sound...the speaker lead was damaged and it was stressing valves.Not healthy unless you have shares in a tube factory!

[acdc126]

in that video marshall sound like peavey

[ufonaut]

Hi, the clip was filmed with a tiny digital camera, and because it was in the house, the amp was very heavily attenuated, so the tone is squashed away to almost nothing. Believe me, the amp in person at a good volume sounded nothing like that!!! It had SS rectifiers, the original set of 6 diodes IIRC. I sold it a long time ago.

[acdc126]

thank you to explain. ss rectifier mean diodes? i dont know everything in english... but i understand that you did something really sad, you sold that amp

:( what you think!?

[acdc126]

575volts on plate!? its very high! is it with 2 gz34? or diodes rectifier... im near to end my project to make my own jtm45/100 with a peavey vtm120, everything is modded i just have to finish the power supply and fix transformers. my toroid PT give 360v, its 10 more than the marshall, i dont think it can go to 575vdc. my peavey 380vac gives less than 530dc

[ufonaut]

I should also have said that your JTM45/100 will work fine on a lower voltage B+, but it will not sound like an original. Lower B+ gives a softer, fuzzier tone, whereas the 575V produces a hard, clean-ish sound with plenty of compression but not fizzy. Think "Wing Cries Mary" or "Hey Joe".

[acdc126]

i think the number of views today show what is a better choice, 5150 :P

[KX36]

that's cool... although i'm pretty sure that change in glow is not the sign of a healthy set up... it also seems like quite a lot of overdrive for a JTM45, maybe that's just me / the vid.

[daneswede1]

test

[Thirdgen83]

Sounds like garbage...

[daneswede1]

YOu need to rethink your setup. Please take this as advice and not be upset about my constructive critisicm. I am a big time gear head and currently run a four head / rig system on tour. Im writing to you from our tour bus outside L.A. . I play with some X members of Sabbath and Malmsteen. Anyway. I use a 1972 Marshall SUperlead 100 watt pt to pt, a 1977 Marshall MKII Superlead 100 watt NMV, 1 981 Marshall JCM800 2203 MV and an 07' Bogner Uberschall

[KX36]

dude.. aere you the roadie guy off wayne's world 2 ;-)

'72 super 100... me want.

[acdc126]

4 heads at same time or switching heads for different sounds...?

[schenker69]

If those tubes had tits I would hump them.

[AmpegV4]

Do you know anything about the old Ampeg amps, Like VT-22, V4, ?? They use KT66/7027A's and I love to play loud like that, only problem is they always blow up on me and end up overheating like that. I have had many V4's do that to me. Too bad they don't last cause I love the sound. I never knew Marshall made amps with these tubes in them, but these tubes are bad ass when you crank them.

[AmpegV4]

Buddy, you gotta watch the KT66, very unforgiving tube. They shouldnt light up like that when your playing. Somthing is wrong with your biasing and it wont last long if your playing all with it on ten...ask me how I know.

[ufonaut]

Hi, biasing these things is a real compromise - set up how it was on the clip, cleans sounded a tiny bit weak and gritty yet the grids were running red like that. Luckily those were GEC KT66's, which could take that "abuse". I sold the amp a few months ago. Note that you can just see the RS De Luxe power transformer at the left of the picture, this was a real early JTM100.

[acdc126]

i did my own jtm45/100 but use dual rectifier when ii want 100 watts ouput. for the moment i dont need that dual rect option. my project is not prfect, it give me only 500VDC and the bias was 40ma with original resistors value. i changed resistors to get 25ma(bias voltage changed from 50 to 60 volts) at high volume the kt66 are a little bit blue. normal?

[IXIBobOhIXI]

Tubes > everything

[daneswede1]

Kind of thin sounding but the grit is there. Make another clip and add some bottom to it. I like how the tubes look like there gonna blow any second when your playing :>)

[KennysKoolKlub]

sexy! i love tubes