Digitech GNX3000-tube amp routing.

[Tommycanoe]

Hi Everyone

I am hoping someone can help me with this. I have a Digitech GNX3000 and have recently purchased my first tube amp. A Traynor YVC80. I am experiencing a high pitched whine and some noise even in the best routing I could come up with. The amp has 2 types of effects loops. This happens even when the GNX is in bypass mode. I am also getting some hum that seems to subside when I touch the strings. The guitar has SCN Fender single coil "noiseless" pickups. I am hoping someone can give me a definitive routing map to get this working as best as it can be as well as suggesting any necessary settings on the GNX. When I use effects on the GNX I use direct amp and speaker hoping that I am not adding an amplified signal to an already amplified signal. Any help would be much appreciated.

 

[Phil O'Keefe]

How do you have everything connected now?

 

I am also getting some hum that seems to subside when I touch the strings.

 

That's typical and normal.

 

When I use effects on the GNX I use direct amp and speaker hoping that I am not adding an amplified signal to an already amplified signal.

 

I don't have a GNX, but "direct amp" would most likely be the type of amplifier sim in it you've selected, and using that one makes sense... if there's a dedicated speaker simulator, you'd want to turn that "off" when using the unit with a guitar amp.

 

[Tommycanoe]

I have a Strat through a Cry Baby on the front end. The processor is looped through the TRS effects loop jack with a "Y" splitter cord. I am not sure if this is the series or parallel loop. This is all a bit over my head. Thanks for taking the time to help.

[Phil O'Keefe]

I have a Strat through a Cry Baby on the front end. The processor is looped through the TRS effects loop jack with a "Y" splitter cord. I am not sure if this is the series or parallel loop. This is all a bit over my head. Thanks for taking the time to help.

 

I checked the Traynor manual, and it doesn't really say if the TRS jack is parallel or serial. The two dedicated jacks (send / return) are definitely parallel though.

 

Do the trim controls for the send and return have any effect on things if you adjust them while using your current connections? If so, try adjusting the send and return levels, as well as the levels on the GNX until you optimize the gain staging - which merely means that the output from one stage (in this case, the GNX) should be high enough to provide a strong signal to drive the next stage (the return on the amp's effects loop) sufficiently hard enough so that you don't have to turn that next stage up unreasonably high to try to compensate for low levels (which leads to noise), but isn't set so high that it overdrives the input of the next stage and causes it to distort.

 

Here's a link to the GNX3000 manual:

 

http://rdn.harmanpro.com/product_doc...B_original.pdf

 

Page 17 and page 25 cover connections and line level hookups, such as using the unit in an effects loop, while page 26 discusses how to optimize the line input levels.

 

You should be connecting the guitar to the wah and plugging into the amp's input, and ideally, two cables to connect the amp's effects loop to the GNX - one from the "send" jack to the Line Input on the GNX, and one from the line output on the GNX to the amp's "return" jack.

[Tommycanoe]

I haven't tried the controls yet because I thought they only affected the dedicated send/return jacks. I seem to get better results with the TRS jack but I will try messing around with these and see how it works. If it doesn't have any effect then I'll try the dedicated jacks and try adjusting the controls with that setup. Also I will check and see if I am plugged into the line input or the guitar input on the GNX. Thanks for your ideas. When I get back from holidays I'll try your suggestions and let you know how I make out.