Set up for ZU103 cart and K&K SUT

Great post by Jbaxley. One minor correction/suggestion: if inserting resistors reduces gain too much, it would be easier and more effective to switch the GCPH to a higher gain setting than to open up the SUT's and change taps.

He can choose 42, 48, 54 or 60 db of gain from the GCPH without affecting the impedance structure. Changing the K&K's gain setting might require starting over with different resistors. No point going in circles!

I agree with both of the posts above. Doug's first point hits the nail on the head: why do you need a step up at all? I hadn't looked up the specs for your phono stage, but now I have. Your GPCH has several different gain settings and different cartridge load settings. The 100 ohm load setting is right in the middle of Zu's recommended range; just use that. And you can easily select the best gain level for your system. You have up to 66 db gain, which is enough for even a passive set up. Your phono stage eliminates any need for a step up transformer.

Hi matem
Thank you for your great feedback.

The GCPH is very flexible phono in the market and sufficient for Zu103. I bought the SUT because I have read a lot of articles (Stereophile) mentioned the superior sounds achived by using SUT togeher with Denon 103 based cartidges.

I did set up the GCPH (no SUT) with loading 47K and lowest gain 42db. I intend to compare between the set up with and without SUT to findout what will be the best for the ZU103. Most of my gears, cart, TT and phono are still in break in period, so it may need another 50 hours at least.

It seemed that the most confused part left for me is the way to opimize the loading by adding or replacing resistor. Does it mean the resistor in the GCPH will need to be replaced ? How did you reach the resistor with a value of 15300 ohms. I still could not find the chart you mentioned in Kevin article, but will explore more.

Also I was told that generally SUT is better matching with Tube Phono, and Head amp is far better with Solid state. Any ideas ?

Thank you very much for helping to improve my understanding.

regards

Victor



"To achieve optimum loading, you would need to add a parallel resistor in one of the values shown in the chart in Kevin's article. For a resistive load of 150 ohms, use a parallel resistor with a value of 15300 ohms. You can buy them at Radio Shack; they're inexpensive."