#1 Zout Maths - is it me?
Posted: Thu Apr 15, 2021 7:52 am
Let me say straight away that maths isn't one of my strongpoints and what knowledge I have doesn't get used much!
I want to know the output impedance (Zout) of the 2P29L preamp I'm working on. The preamp is using the Bartola schematic with his (Ale's) Mu Follower 'Gyrator'.
https://www.bartola.co.uk/valves/2017/0 ... ht-preamp/
https://www.bartola.co.uk/valves/2016/0 ... l-pse-amp/
Ale has a blog post on his website about calculating Zout so I thought I would try and learn by following it.
https://www.bartola.co.uk/valves/2018/0 ... impedance/
I thought the obvious starting point was to verify my maths by working through the 'proof of the pudding' example so I created a little spreadsheet to input the variables and perform the calculation. Once I get that taped I can move on to substituting the relevant values for the 2P29L scenario. I've attached the 'proof of the pudding' equation example below - my problem is I don't get the 356ohm answer when I work though it - is it me?
I want to know the output impedance (Zout) of the 2P29L preamp I'm working on. The preamp is using the Bartola schematic with his (Ale's) Mu Follower 'Gyrator'.
https://www.bartola.co.uk/valves/2017/0 ... ht-preamp/
https://www.bartola.co.uk/valves/2016/0 ... l-pse-amp/
Ale has a blog post on his website about calculating Zout so I thought I would try and learn by following it.
https://www.bartola.co.uk/valves/2018/0 ... impedance/
I thought the obvious starting point was to verify my maths by working through the 'proof of the pudding' example so I created a little spreadsheet to input the variables and perform the calculation. Once I get that taped I can move on to substituting the relevant values for the 2P29L scenario. I've attached the 'proof of the pudding' equation example below - my problem is I don't get the 356ohm answer when I work though it - is it me?