Matching stepup to phono stage

Keep the CJ loading at 47K.

You need to choose the right step-up transformer to present the recommended loading of the cartridge AND simultaneously give you the correct amount of gain. The impedance presented to your cartridge will be the combination of the 250 ohms of the step-up and the 47Kohms of your phono stage.

Adding resistive loading to inductive loads, pace Bent Audio, is not recommended.

Patrick

Patrick

Why are you not recommending Bent Audio.

"The impedance presented to your cartridge will be the combination of the 250 ohms of the step-up and the 47Kohms of your phono stage."

OK, but how do they interact. How can the "final" impedance be calculated?

Rhbblb1 - if you send me an email offline I will send you a spreadsheet that I used that will do the calculations based on different step-up ratios in combination with the resistor values of the step-up and phono stage.

As an example. I used a K&K Audio step-up with a Hagerman Trumpet. The step-up had a 10:1 ratio. Using 47k ohm resistors in the step-up in parallel with the Trumpets 47k ohms yielded 940 ohms.

Actually Bent Audio has a great page and chart explaining this.

http://bentaudio.com/parts/tx103loadhow.html