KT88's Vs. EL34?

[ianwrecked]

Hi! I've heard that replacing the stock EL34's in a Rockerverb 100 with KT88's will really make a huge difference. I realize that KT's are really high-powered tubes, but does it affect the power that much?

[a.hun]

Hi! I've heard that replacing the stock EL34's in a Rockerverb 100 with KT88's will really make a huge difference. I realize that KT's are really high-powered tubes, but does it affect the power that much?

Hi!

Well the KT88 is pretty much an upgraded 6550. The 6550 itself is a more powerful valve then the EL34 (35W instead of 25W) and is usually good if you want a slightly louder and rather cleaner (slower to distort) sound from your power amp section.

Though the amps transformers etc should allow a bit more power with the more powerful valves the volume difference won't actually be huge. The tonal changes wll probably be more noticable. Whether or not you'll like them is nother matter...

You would of course have to have the amps biasing checked for the new valves by an amp tech. But that is true of any new set of power valves, even of the same type...


Andy.

[Orphin]

Hi! I've heard that replacing the stock EL34's in a Rockerverb 100 with KT88's will really make a huge difference. I realize that KT's are really high-powered tubes, but does it affect the power that much?

Personally, I wouldn't think that I would use the word "huge" difference. There will be a tone difference for sure, but it's still the same amp, and it will always sound like this amp, but a little different.
If you've heard that it will make difference as in "better", the person who said it really meant that it was better to him. Doesn't necessarily have to be better for you.

[a.hun]

Personally, I wouldn't think that I would use the word "huge" difference. There will be a tone difference for sure, but it's still the same amp, and it will always sound like this amp, but a little different.
If you've heard that it will make difference as in "better", the person who said it really meant that it was better to him. Doesn't necessarily have to be better for you.

I'd agree with a lot of that, especially the last comments. But while maybe not 'HUGE', there will likely be a pretty noticable difference, especially I'd think in tone and feel. Whether it'll suit you (or the Orange amp) or not, well that is something only you can decide.

Look at it this way. Big Marshalls way back, like these days, used EL34s. Then at one point they started using 6550s for US distributed ones. That lasted for about 10 years or so I think. The 6550 amps gained some clean power, yes, and probably made better bass amps. But with guitar a lot of people (not all, mind!) thought they lost a lot of their 'Marshall' character. The character of the distortion they got with the 6550s wasn't nearly so gnarly, but a lot more in your face, and it didn't happen anything like as progressively either. Was the little bit louder worth it or not?

One of the most popular Marshall mods (surprise surprise!) was changing the bias back to run EL34s. Though of course some guitarists and bands did thrive on the 'US Marshall sound'.

Probably pretty surprisingly to many though, it is actually very debatable whether much at all of a cranked 100W 'Plexi' Marshalls great distortion is actually true power valve overdrive. That really depends on which stage distorts first and foremost: preamp stages, (tone stack), the phase inverter stage, or the power valves themselves. Sometimes the answers can be surprising and not what you'd think at all. And remember, a Marshall is going to be different from say a Hiwatt on that sort of score, and both are likely to be very different again from an Orange.
http://www.thegearpage.net/board/showpo ... stcount=19" onclick="window.open(this.href);return false;

That hardly matters though, the differences between using the different power valves sound and are real enough...

Purely a matter of taste. Feel free to try it out yourself ianwrecked, making sure to have the valves properly biased - not just by flipping the switch on the back! And you could report back on whether or not it really worked for you.

For me though the ability to change from the standard power valves really isn't a huge selling point of the RV.100. All it does is just to make it a little easier for your tech to change the bias range. (And much easier for someone to switch it wrongly by mistake! ) A tech will still need to open the amp up to do a proper bias check though. And anyway it is by no means impossible to convert many other amps. Myself I might be tempted to do it with an EL34 amp for playing bass. But then I'd never buy a Rockerverb purely for bass...


Andy.

[flea]

Would you be able to put KT88's in the R30? I just tried the KT77's and didn't really care all that much for it, but I'm just kinda curious. I'm still learning about tube amps, really.

[a.hun]

Would you be able to put KT88's in the R30? I just tried the KT77's and didn't really care all that much for it, but I'm just kinda curious. I'm still learning about tube amps, really.

Head, yes, combo no!

KT88`s will work in a Rocker 30 head but they wont fit in a combo as they will hit the speaker! You will also need to change the cathode resistors from 330ohm and 270ohm 4W to 470ohm and 470ohm 6W!
The Rocker 30 head will then run on KT88/KT66/6L6/5881/6550 with slightly different power and tone!

Thread on using KT88s and 6V6s in the R.30:
(http://forum.orangeamps.com/viewtopic.php?t=7263" onclick="window.open(this.href);return false;)


Andy.

[flea]

Ok, cool, thanks Andy! Not going anywhere near that one as I like my R30 too much to butcher it, and it's a combo anyway.

[a.hun]

Ok, cool, thanks Andy! Not going anywhere near that one as I like my R30 too much to butcher it, and it's a combo anyway.

Man, I know what you mean. I'm still totally loving the sounds of my R.30 combo on its original valves! (JJ pre's and EH6CA7s.) Suppose I'll get around to swapping out some of them at some point, probably trying some old Tesla EL34s for starters, and who knows what in the preamp.

But 'till now I've really never felt the need!


Andy.