LF Lift in the KT88

[John Caswell]

Noel's review was May 2012 latest version.
Not much else to say.

John

[Richard]

Originally Posted by John Caswell

Noel's review was May 2012 latest version.
Not much else to say.

John

Hi John,

You've not much else to say or Noel didn't? I didn't see the May 2012 review. Did he like it?

In the Dec 2000 one when it was launched he found response 17Hz to 30KHz -1dB which is impressive and very similar by the sounds of it to the current version so all is well there then

[John Caswell]

Hi Richard et al
Yes basically he liked it.
"The KEL84 measured neatly all round. It will need to be used with sensitive loudspeakers, but it will give an easy valve sound. Freq resp was limited to 20.4kHz before rolling away slowly so KEL84 will sound fairly easy going. At the low end bass rolled down slowly below 50 Hz measuring -1dB down at 16Hz." NK

Personally I have always liked this amp as it always sounds good and performs well, it just doesn't have enough ooomph for my system. I am reminded of the WAD 6550 and the WD88 where everything just fell into place nicely to produce great amps with excellent results.

John

[Phil Y]

Originally Posted by John Caswell

In response to PhilYs comment "I was just thinking that it made logical sense to perform the same check across the entire WD amplifier range".
No it doesn't really, a lot of the amps have been going for 15 years or more and it is really impractical and possibly verging on the ludicrous to do this, especially if it is, say, an output tx problem, as we couldn't do anything about it anyway.
I repeat, I remain convinced that there is nothing to worry about.

John

My fault John, I was being a little tongue in cheek but did not make my meaning clear. I meant the entire current range (two) of WD amps.

Regards Phil.

[Richard]

Originally Posted by Phil Y

My fault John, I was being a little tongue in cheek but did not make my meaning clear. I meant the entire current range (two) of WD amps.

Regards Phil.

Strange how we read things I'd read it as meaning WD88 and Kel84 and couldn't understand why John's reply was, err, not very enthusiastic

[Richard]

Originally Posted by John Caswell

Hi Richard et al
Yes basically he liked it.
"The KEL84 measured neatly all round. It will need to be used with sensitive loudspeakers, but it will give an easy valve sound. Freq resp was limited to 20.4kHz before rolling away slowly so KEL84 will sound fairly easy going. At the low end bass rolled down slowly below 50 Hz measuring -1dB down at 16Hz." NK

Personally I have always liked this amp as it always sounds good and performs well, it just doesn't have enough ooomph for my system. I am reminded of the WAD 6550 and the WD88 where everything just fell into place nicely to produce great amps with excellent results.

John

Thanks John, I must have missed seeing that article in there. I usually have a peek and buy the mag if there's something interesting. Looking out the original supplement for Kel84 made me realise they were exciting (for me anyway) years 1993 to 2003 when HFW did WAD kits and valve articles. Crikey the first kit was nearly 20 years ago now. It seemed to peak somewhat after that when the Chinese got on board for good or bad.

Yes great amps the KT88/6550 series and I still have an idea I'll own a Kel84 at some stage too. I've stashed some valves along the way ready. Power won't be an issue as the 10W Glasshouse I'm using presently is quite enough with the Castles though it does have a powerful bass. I've heard 2 Kel84s here at home but never owned one, both times I've thought, oh, that's nice.

I think, strangely, that previously having a Leak ST20 put me off as that was el84 but a different sound, nearly there but not quite. Kel84 is more refined imho.

[Phil Y]

Hello Richard,
I was a long time Stereo 20 user (about 20 years) before I moved on to the KEL84. There is no doubt in my mind that the 84' is a better sounding amp.
More dynamic, more detailed and a lot crisper at both frequency extremes. I have also found the 84' more responsive to passive component upgrades, which I feel suggests it's a fundamentally more capable design.

Regards, Phil.

Hi all,

Apart from correcting the low frequency lift, does the change of C1 from 0.1 to 1.0 uF have any audible sonic effects - good or bad?

Steve

[John Caswell]

Hi Steve,
According to Matthew who did some long term listening, no!

John

[bob orbell]

Yes I agree with that, no change at all in sound quality. BOB