UntilThen
Headphoneus Supremus
- Joined
- Jun 16, 2015
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Eric sent me a 12AV7 that has a mu of 37. I have had good results with a similar tube that has a mu of 47. To me it seems to be more an art than science how to match up drivers with power tubes in relation to the mu - trial and error.
On the other hand, it seems to me that some people have some kind of formula in mind when they match up input and output tubes. Perhaps someone can explain to me if there is a way to predict the synergy between input and output tubes?
It's more to do with the headphones you're using. With a warmer sounding headphone like Atrium, you'll want more energy from your tubes, hence higher gain. With a very inefficient headphone like Susvara you definitely want higher gain tube.
With my very efficient Grado GH1, a 20 mu is more than sufficient. The less the better with Grados.
I think it's common sense to match bright drivers with warm power tubes to balance it out and vice versa. However sometimes uncommon sense prevails when you specifically choose a bright setup or a very warm setup.
For example I am usually someone who prefers transparency and neutrality but when I listen with Audeze LCD4 and Auris Nirvana, the chocolate syrupy sound taste good in mouth literally.
So no formula. On Monday, you like bright sound. On Tuesday, a bit more moderate. On Wednesday you're almost over the hill, so you start to gravitate towards warmth. Come Friday, you're all blues and smokey. On the weekend, you pass out and just sleep in.