WarmothRules
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Has anyone put in a lot of time with these two different power tube types? I've read that a KT-88 could be viewed as an oversized EL-34 and a 6550 could be viewed as an oversized 6L6.
KT-88's VS 6550's
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er... sort of ... almost.
The oversize 6L6 - the real one is the 7581. That is the extra extra large plate 6L6 that has the same filament current, same bias range, but will dissipate 35w per tube. Those just kick major butt. They also - somehow - have the same plate impedance, or so close to the 6L6 that it doesn't matter. Four of those in a Twin Reverb is abuot as clean as clean can get....
The oversize 6L6 - the real one is the 7581. That is the extra extra large plate 6L6 that has the same filament current, same bias range, but will dissipate 35w per tube. Those just kick major butt. They also - somehow - have the same plate impedance, or so close to the 6L6 that it doesn't matter. Four of those in a Twin Reverb is abuot as clean as clean can get....
Let me add.... EL34's have a charm and magic.... all their own. No matter the brand, those long skinny envelopes just have their own flavor.
Similarly, 6550's have their own, but.... Its not a flavor we usually associate with guitars. Notably, the 400PS bass (Fender) and the SVT... were 6550'd. Sun used them. They are made for, and used for high clean output. They dont sound good when they do finally distort and most amps cannot drive them hard enough to distort, no matter how the bias is set. The 7581 has a hard time being driven to distort in Fender designs, but is a drop in replacement for any 6L6.
Similarly, 6550's have their own, but.... Its not a flavor we usually associate with guitars. Notably, the 400PS bass (Fender) and the SVT... were 6550'd. Sun used them. They are made for, and used for high clean output. They dont sound good when they do finally distort and most amps cannot drive them hard enough to distort, no matter how the bias is set. The 7581 has a hard time being driven to distort in Fender designs, but is a drop in replacement for any 6L6.
jackthehack
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And they both have enough effects to require an effects tech....
WarmothRules
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jackthehack said:
I can proudly say the only effect I use is the distortion in my guitar head.
SlingeroGuitaro
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i prefer the kt-88 in everything i have- from modified marshalls to the mesa strategy 500. i use a marshall jmp-1 pre amp, and through an el-34 or 6l6 based power amp i get a great crunch, but through a kt-88 based amp it turns into an outright growl.
SlingeroGuitaro
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i use a mesa power strategy 500- i pretty much dime the power amp when i'm playing live, and feed very little pre-amp signal to the 500. it does break up, it just doesn't want to :glasses10:
of course, i can't hear now, so who knows how it really sounds :laughing11:
WarmothRules
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I just went with a 6L6 power amp. Should be here next tues :headbang1:
SlingeroGuitaro
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WarmothRules said:
this post will be useless without clips :headbang:
Patrick from Davis
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The 6550 were used by the metal heads to get a very dry crunchy tone. The amps had to be modded to get this. The El 34 has a very warm tone, sometimes considered a bit to muddy for the metal head. The KT 66, and 77 are somewhere in between those two. The KT66 are a replacement/analog (hmmm...) for the 6L6. I don't have anything to use them with so I'll pass on a review. I have a KT77 (JJ Tesla) in my home grown amp and it has the sound I wanted. It is a drop in replacement for the EL34. The EL34 was too warm for the intended hotrodded amp sound. The EL34's sound great if you are playing a lot of tunes that call for that warmer neck pickup sound, or are looking to cut down on the crunch type sound. I noticed that a lot of the players today are using the 6550 in the amps that they use for clean tones, probably for the reasons the CB noted.
Other things to note is that the sounds I listed above were for the Marshall style of amp (hi gain) that was used during the late 80's. Different amps do sound different with the same tubes.
Also, another ways to push power tubes is to replace the 12AX7's pre amp tubes with 5751's (I like the JAN's) because they give ~30% less output. Then you crank up the amp's volume and give the power tubes more electrons to play with. Fun, fun. SRV liked to do that with his amps. They are also a drop in replacement tube, except for the 12AX7's... Hope this helps.
Patrick
Other things to note is that the sounds I listed above were for the Marshall style of amp (hi gain) that was used during the late 80's. Different amps do sound different with the same tubes.
Also, another ways to push power tubes is to replace the 12AX7's pre amp tubes with 5751's (I like the JAN's) because they give ~30% less output. Then you crank up the amp's volume and give the power tubes more electrons to play with. Fun, fun. SRV liked to do that with his amps. They are also a drop in replacement tube, except for the 12AX7's... Hope this helps.
Patrick
Patrick from Davis said:
I'm sorry... but thats just not true. Change tone, yes, gain mod (lower!) yes. More electrons to play with... tripe.
The 5751 is comparable to putting 12AT7's in. The 5751 is... a low noise, mil spec 12AT7. A bit better dissipation, a bit lower gain.. than the 12AX7. If you want "cleaner" this will do it. OR - if you need less noise - it will do it too. When do you need less noise? Like when you got it dimed. You win on noise, lose on gain.
WarmothRules
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Eh looks like I got a 6L6 power amp. peavey classic 120. Got it used with 15 year old tubes. Does it need new tubes CB?
DiMitriR33
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SlingeroGuitaro said:
are ya shore that's not the speakers hitting x-max, or maybe your eardrums doing the same?
M
metalman22105
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I Love KT88's they sound great (and yeah, they sound kind of EL34-ish to me, IMHO of course)
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