Dear Mate,
Lynn Olson suggests to extend the bass response of his Ariel loudspeaker by using active filter to the low pass, the ARIEL would be passively filtered with a high pass between the preamp and amp, look at this:
http://www.nutshellhifi.com/ME2txt.html#swactive
Now, my question is how do I design such a filter? How to choose the series cap and the resistor to ground? There is any way to come up with a value? Has somebody experimented with such a thing?
Thanks for you interest.
Cheers
Pierre
Lynn Olson suggests to extend the bass response of his Ariel loudspeaker by using active filter to the low pass, the ARIEL would be passively filtered with a high pass between the preamp and amp, look at this:
http://www.nutshellhifi.com/ME2txt.html#swactive
Now, my question is how do I design such a filter? How to choose the series cap and the resistor to ground? There is any way to come up with a value? Has somebody experimented with such a thing?
Thanks for you interest.
Cheers
Pierre
Pierre,
Assuming that you are going to "dedicate" a tube amp to the high pass channels, it is as simple as either placing or "re-placing" the input coupling cap on the input tube with the correct value for the 80hz F3. You might need to change the grid load resistor to match well with the cap.
here is a calculator
I would need the schematic of you tube input to help further.
But an example would be .0047uF cap with a 390K grid to ground would give about 87hz F3.
A 200K and .01uF would be 79.6hz close enough?
Assuming that you are going to "dedicate" a tube amp to the high pass channels, it is as simple as either placing or "re-placing" the input coupling cap on the input tube with the correct value for the 80hz F3. You might need to change the grid load resistor to match well with the cap.
here is a calculator
I would need the schematic of you tube input to help further.
But an example would be .0047uF cap with a 390K grid to ground would give about 87hz F3.
A 200K and .01uF would be 79.6hz close enough?
...
I would need the schematic of you tube input to help further.
Hello,
for the mid-highs I use a Primaluna Prologue 4 (it's a 35Watts PP of EL34).
Thanks
Pierre
Doug do you mean don't exceed the maximum grid resistance? I don't recall seeing a maximum cathode resistor spec in most data sheets. Also, I believe charge builds up when the grid R is large, i.e. greater than 1.5-5Meg, like grid-leak bias. I may not have totally understood!
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