Author Topic: yet another llama/tsf question...  (Read 826 times)

m_charles

yet another llama/tsf question...
« on: August 12, 2007, 03:18:02 PM »
Hi,

I'm building a red llama clone, and I had a question. I seem to remember reading a while back that you can tweak the 100k input resistor to affect the highs and lows. With my little understanding of electronics, I believe lowering it would let in more highs. Is this correct? Will this also chop the lows, or only add some highs?

I appreciate everyones help, but I have searched and read a ton of postings on the RL, mark Hammer's mods, other mods, hot harmonics etc. So no need to reccomend other mods, cap changes, etc., was just wondering about this in-resistor specifically.

thank you!

chuck

brett

Re: yet another llama/tsf question...
« Reply #1 on: August 13, 2007, 05:51:01 AM »
Hi
the 100k resistor affects the gain.  As gain increases, it probably sounds like treble increases, because the distortion products will be high-pitched harmonics. 
To tweak the lows at the input, you can decrease the value of the input cap, though the values will probably have to be very small before you restrict the amount of bass.  e.g. a few pF  This is because the input impedance of MOSFETS is so high.

An easier solution is probably to add a cap to ground after the 100k resistor and before the cap. This will filter out highs, with larger caps filtering more highs.
cheers
Brett Robinson
Let a hundred flowers bloom, let a hundred schools of thought contend. (Mao Zedong)