Tube Rolling - No Change in Sound


In my Wyetech Opal pre, I substituted NOS Ken Rad VT231's for JAN Philips WGTA's in the input stage, expecting more body and warmth to sound based on Ken Rad reputation. But nothing has happened; I perceive no audible difference from the switch in tubes! What's up with this? This was my first foray into tube rolling.

Neal
nglazer
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Don't know who told you KenRad VT-231s would add anything to your sound. They are a very transparent tube, adding/taking nothing from the signal(as are the TungSol Round plates, Sylvania VT-231/6SN7GTs and 6sn7Ws). Raytheon, National Union, and RCA VT-231s will all give you a bit more of the sound you're looking for, to various degrees. They are all a little euphonic(warmer) than the others. I've got three matched NOS pairs of the KenRads, for when I can't find(or afford) the TungSols and Sylvania 6SN7Ws that I love so dearly(for the above mentioned reasons).
Msstl's number one response is probably right on...I would have contacted the MFG and asked what tubes in the unit respond most to rolling...just changing tubes out doesn't always change the sound...the KRads are great BTW
Well, trounce me if you want, but I still STRONGLY maintain that the sonic signature of any system is at least 85% determined by the amp and speakers. As for preamps, I think one thing you WILL get out of tube rolling is (maybe) a quieter/lower noise floor (depending on the tube you select.) This is certainly true for tubed phono preamps. But the amp is where I'd look to effect tonal changes through tube-rolling.

Of course if you have a solid state amp, you're going to get the detail and slam for which ss is well known. But if you don't like the sonics, you'll have to roll the whole amp!
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Of course if you have a solid state amp, you're going to get the detail and slam for which ss is well known. But if you don't like the sonics, you'll have to roll the whole amp!

Nsgarch (System | Threads | Answers)

I laughed at that! Good one Nsgarch :o)