could have placed this topic in tech forum,,, but as the amp page gets more attention and this has critical importance as to how our am will voice, thought we would share what we know about the KT90.
I plan to swap out these Svet 88 aka 6550, same thing (88 = 6550) for a set of KT90's.
As you all know the 88 has a much greater popularity as power tube by popular demand.
Perhaps this has to do with the fact that the majority of audiophiles have xover low sens speakers which need as much full midrange as they poosibly can get , the best tube for the job is the 88.
But as I have FR speakers,, I dont need/want the 88 **bloomy** midrange.
I am hoping the 90 has a bit toned down mid section.
Now dont in and claim ** just the oppostite, 90 has more forward mids..*
Again I don't expect much of a sound dif, nuance, minisclue at best.
But a miniscule is all I am hoping for.
Bass and highs not that much interested.
can't find much of anything about the KT90 on the Inet/YT.
Its alllllllll about the 88.
Its like the 90 has been thrown under the bus and then steamed rolled over.
btw the EI's did in fact have some issues, but the legend lives on.
They make music sound alive in my JOR but had a steely/harsh (distorted) top end) But not fatiguing in any degree.
Now you are wanting to know **harsh top end,,but not fatiguing..??? how is this possible..**, I find the fatigue factor has much more to do with the 120hz range,,, muddy, greyish, resonances in the low end.
So in fact the EI90 has this super clean, live soundstage in most fq;'s, except some of the upper range,
The EI was not a long lasting tube as well.
Electro Harmonix has corrected the issues in the EI type.
In 3 months we will find out.
