DIfference between KT88's and EL34's

[Gearjoneser]

Re: DIfference between KT88's and EL34's

Tonally, EL-34's have more crunch to the tone. Bigger bottles shift the EQ bassier too, so while your EL-34 EQ may be P5, B10, M6, T2, your 77, 88, 6550 EQ will be P4, B8, M7, T5.

[beaubrummels]

Re: DIfference between KT88's and EL34's

Jimi had his Super Leads set up to run 6550s in class B, mainly due the fact that he wanted more clean headroom and increased reliability, as he was having many EL34s failing and taking out his Output Transformers. He was also not happy with the ever increasing agressiveness and brightness of the high treble channel in the Super Lead which did not work well with a single coil Strat bridge pickup and a Silicon Fuzz Face...he also preferred the older shared cathode to the later split cathode preamp. As far as I know he was the first Artist to do this, then in the mid 70s, Unicord, Marshall's USA distributor requested that all USA EL34 Amps be set up to run 6550's mainly for their increased reliability, as the Super lead will easily exceed the design limits of EL34s at full tilt....

Post #2, only 10 years later. Nice to catch up.

Tonally, EL-34's have more crunch to the tone. Bigger bottles shift the EQ bassier too, so while your EL-34 EQ may be P5, B10, M6, T2, your 77, 88, 6550 EQ will be P4, B8, M7, T5.

I actually understood that.

[esandes]

Re: DIfference between KT88's and EL34's

huge difference. the bigger the tube, the more headroom basically. the EL-34 has more mid range growl.

[eljefe3126]

Re: DIfference between KT88's and EL34's

I don't think anyone quite answered the original poster's question, namely, what do KT-88s sound like? To that, I'd say that you've heard them before, but just not realized what you were listening to. Both Marshall and Hiwatt made amps based on the KT-88.

The Marshall Major used 4 KT-88s to generate about 200 watts. The first verson of it (known as the Marshall "Pig") had one supply voltage for the plates, and a lower supply votage for the screens (this is the conventional way to wire up a pentode). Mick Ronson used that version on a lot of Bowie songs and other things. Here's a clip of a gentleman playing some of those licks through a vintage "Pig":

https://www.youtube.com/watch?v=qHav_y8doTg

After a year or so, Marshall revised the Major to wire up the tubes in the "Ultra-linear" fashion. This was a technique borrowed from hi-fi, where the primary side of the output transformer had an extra set of taps, about 40% of the way from the center tap to plate taps. The screens were wired into that, and the same B+ voltage was used for both the plates and the screens. That's the version that was used by Ritchie Blackmore. Listen any Blackmore tune from his Deep Puple or Rainbow days, and you'll hear a Strat through 4 KT-88s.

Hiwatt made two amps with KT-88s, both wired in conventional (pentode) fashion. There were 2 versions of the 200-watt DR-201, one with 6 EL34s, and one with 4 KT-88s. The DR-405 used 6 KT-88s, and Hiwatt claimed a 400-watt output for it.

I don't know of any guitarists who used the DR-405; it was marketed to bass players. The DR-201 was marketed as a bass amp, too, but it works just fine for guitar or keyboards. Since I don't know which guitarists used the EL34 version of the DR-201 and which used the KT-88 verson, let me just link to a man showing off his vintage DR-201 with KT-88s:

https://www.youtube.com/watch?v=3JVGjonKABQ

You can listen and draw your own conclusions. To my ears, the KT-88s are just more articulate than other tubes. When someone cranks an EL34 amp, I hear a lot of mids, and they're muddy to me. When someone cranks a KT-88 amp, I hear the highs and the mids and the lows, all without the mud. The clean tones have a lot of headroom, so you have to make a deliberate choice to push it into overdrive. But if you stand on it hard, you can get all the distortion you want. To my ears, it's a big sound, and I love it.

[GoldenVulture]

Re: DIfference between KT88's and EL34's

I don't think anyone quite answered the original poster's question, namely, what do KT-88s sound like?

Well it was ten years ago, i doubt it really matters anymore. [ 02-03-2006, 05:13 PM #1 ]

Don't get me wrong , I use an amp that has a pair of KT88's and I'm currently hacking together one using a quad of them.