Build Inquiry: OpenTheremin V3, NVX XGLI35, WM-047 HiFi 47 PreAmp

I have the following components: 

1) OpenTheremin V3, SeeedUino v4.2 shield
2) NVX XGLI35 Ground Loop Isolator
3) WM-047 HiFi 47 PreAmp

What is the ideal/correct order to route the audio from the OpenTheremin V3 through, so that it can go out into my speakers for playing?

I was not using either of the GLI nor the PreAmp before, but after spending an extensive amount of time with Peter Theremin during lessons trying to stabilize and improve the sound from my OpenTheremin, I settled on just using the GLI, which was a massive improvement over having nothing.

I want to add in the PreAmp, if that would help the sound quality/stability.

I also may swap my SeeedUino v4.2 for the current v4.3, but that is mostly for convenience flashing it under Linux as the Serial to USB chip has been swapped to something more common/standardized. I do not see, nor anticipate, any other board-level improvements there that might change anything.

Hello Saijin,

current is V4.5.
The real important thing for a go or no go when you use your OpenTheremin is a direct ground connection to earth ground  (for ex. by power connector ground).
The second important thing is an extra power adapter only for the Theremin. 
Not every power adapter worked for me on my V4.5, so test a few different.
And the layout now on the V4.5 is important for better reduction of inteference with the Arduino!!!
In V4.5 the Atmega328 is better isolated from the Volume/Pitch circuits.
Maybe your non Arduino Seduino is a pain in the ass for a good tone and control of your V3 shield.
Layout and MC can matter here.

My 2 Cents
Chris

On the Seeduino pseudo Arduino they added buck converters and some USB relocation.
Buck converters can make severe problems on ground equality, resulting in ground loops! 

Your amplifier is a joke for a good sound

If you look for a good not very expensive and working portable amp for your Theremin:
Joyo MA-10E (guitar amp) batter and 9V power plug powered (included) for 35 Euro here, so should be around 40 US$
If you want a Headphone only solution take an Vox AmPlug2 clean for about 25US$.
That's what i use for OpnenTheremin V4.5 and Etherwave standard.

My 2 Cents
Chris

Chris,

Thanks for the replies.

Let me constrain my opening question further: 
Given that all the hardware is already purchased by me, assume that none of it can be replaced with newly purchased hardware.

How best to approach interconnecting each element to improve my output?

In my opinion to use more than your extremly cheap headphone amp makes no sense at all!
As i said in my first post... there are several things to get it working as it should.
Just try it!
 

Chris,

Thanks again for your opinions on my equipment.

I will keep this open as my original inquiry still has not been answered.