kt88/6550 differences ?

[MYLILSS]

i was curious tonally what the differences are between kt88's and 6550's ? i recently tried a pair of kt88's in my jsx, and loved the way they sounded. no i didnt blow anything up, played it like this for several hours and nothing. only problem with kt's i i cant fit 4 in there. 6550's will fit. if there is too much of a difference i will just continue running it at half power, but contemplated running 6550's if there isnt a massive amount of difference, or if the difference may be in a better direction.

 

[nitro]

6550s sound more aggressive then KT88s,they have more presence and tight sounding.

 

[Loudness250]

There are different size kt88's maybe you can fit some smaller ones in that amp.

 

[Ventura]

Can't really say 'generally' speaking. They can react very differently from one amp to the next. I like KT88's for huge headroom and lots of 'clarity'. I don't find them the most appealing tubes for powersection saturation. Yes, the TwinJet (for example) is loaded with KT88s, but the TJ's gain comes from the preamp stage, not the poweramp section (IMHO). I have a poweramp right now that's used for all-headroom, zero-color (as best as possible, anyway), and it's loaded with KT88s. I run my Axe through it and my Mak4. I can't imagine ever hearing this thing get close to saturation (a small nuclear-like explosion would be recorded in the PNW if I ever got it that loud )

My experience with 6550 is that they're bloody nasty (good nasty) sounding tubes. I have them in my VH4S and wouldn't trade them for anything. I like them a lot. Smoother than the EL34s, higher top end on them, fatter gain and in this particular amp, I do go for some heavy power section saturation!! But again, all amp dependent.

Hope this helps

V.

 

[MYLILSS]

Thanks for the info ventura. Clean headroom isnt something i need so i think imma go ahead and try the 6550's. My main concern was losing the low end punch the kt88's give. The kt's definately sound better in here than the 6l6's did, but 6550's sound like they will be another step in the right direction for where i want this amp to go

 

[Giga]

If low-end is your main concern, stick with the 88's. They are bassier for sure (or at least the ones I compared were). 88's Also have thicker/ more prominent low-mids.

Giga

 

[O'Rourke]

To my ears with the same brand of all three in the same amp 6550's still bring the mids while being more extended than an EL34, sort of a pissed off EL34 with more high end and a touch tighter and heavier low end. KT88's are more of a "full range" tube, they bring more of everything without heavily focusing on any particular area the way 34's tend to be mid focused for example.

You're not going to hear much difference untill you crank it up and really push the power section though.

 

[MYLILSS]

To my ears with the same brand of all three in the same amp 6550's still bring the mids while being more extended than an EL34, sort of a pissed off EL34 with more high end and a touch tighter and heavier low end. KT88's are more of a "full range" tube, they bring more of everything without heavily focusing on any particular area the way 34's tend to be mid focused for example.

You're not going to hear much difference untill you crank it up and really push the power section though.

Sounds good. Ive never tried the amp with 34's in it. This one has always had 6l6's in it since i have owned it. Based on yours and ventura's decisions i think imma give a set of 6550s a shot. Thanks

 

[JTyson]

I think the 6550's are more "mechanical" sounding than the KT88's. Tighter and a little more focused. If you do metal, I would go with 6550's. Other stuff, I would probably prefer the 88's

 

[Laura]

To my ears with the same brand of all three in the same amp 6550's still bring the mids while being more extended than an EL34, sort of a pissed off EL34 with more high end and a touch tighter and heavier low end. KT88's are more of a "full range" tube, they bring more of everything without heavily focusing on any particular area the way 34's tend to be mid focused for example.

You're not going to hear much difference untill you crank it up and really push the power section though.

I agree with this. I like KT88's because I hear a bit more saturation, less snarl in the mids and a bit more "oomph" in the low end.

 

[Shawn Lutz]

Can you run KT88's in place of 6550's? To me the best Marshall's JMP/JCM800 2203/2204's are the 6550 versions.

 

[hellaboogie]

I like the big bottles