Yes and no. The 50k pot and preceding output Z are in parallel from the perspective of any signal trying to couple onto the cable from a remote source, e.g. ambient hum.
But the output Z and pot are in series from the perspective of the wanted audio signal being fed onto the cable.
Is the impedance only 50K at minimum volume as the source cannot "see" the load beyond the POT, then fixed all the way up from minimum volume to maximum? Just checking my understanding that the input impedance is indeed fixed on a standard POT while the output varies depending on the level.
Thanks
It doesn't really "sound" like anything. Dead quiet and transparent really. I'm running it from an SMPS which is why I didn't need the Aikido mojo
Thank you again, I think I am getting my head around this now!
I am wanting to put these calculations into a spreadsheet for future use.
I am considering whether I could wire up two pairs of outputs from my ACF build, an unbalanced pair and a balanced pair.
If I was to use a simple 1:1 center tapped transformer to create a balanced output, is there anything else to consider with regards to the effects of the input impedance of the transformer and the output impedance looking into the power amp that the ACF would be connected to.
Is it simply a case of using a 1:1 transformer and the impedances will be the same as if I had not used the transformer and simply wired up unbalanced outputs at the output of the Aikido ACF?
I was looking at a pair of second hand Sowter 4231
(Primary 600 Ohm - Secondary 600 Ohm - Ratio 1:1)
many thanks.
If I was to use a simple 1:1 center tapped transformer to create a balanced output, is there anything else to consider with regards to the effects of the input impedance of the transformer and the output impedance looking into the power amp that the ACF would be connected to.
Is it simply a case of using a 1:1 transformer and the impedances will be the same as if I had not used the transformer and simply wired up unbalanced outputs at the output of the Aikido ACF?
I was looking at a pair of second hand Sowter 4231
(Primary 600 Ohm - Secondary 600 Ohm - Ratio 1:1)
many thanks.
Sorry, I hope you don't mind, I am just returning to this calculation. I understand that this is with the POT halfway, the maximum output impedance and either side of this it is lower, but how, in terms of a formula, would I calculate the output impedance if the volume control is not at halfway?
Is it something like the output impedance of the source + the series leg of
POT and this total in parallel with the shunt leg of the POT?
Using this method with a standard 50K POT at half vol and 3.5K source as above, I get 13,317.76 which is close to the 13,375 in your answer above but not correct so my formula is obviously not correct.
many thanks.
Thank you for your help it is much appreciated, yes that does make sense now thinking it through. I have read a number of articles online around this subject and a number of forum threads also but have not been able to nail it down until now.
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