Roadster with Triaxis / Ground Loop Problem

[reuveu]

Hi Guys,

I have recently bought a Triaxis V1 which I plugg into a Roadster head as poweramp
The sound is diabolic but I wanted to use both preamp (i.i Roadster and Triaxis)
Therefore I bought a GCX which is control with a Ground Control

the schema is the following
Guitar -> IN GCX
OUT GCX -> IN Loop1
Send loop1 -> IN Triaxis
Output Triaxis -> Return loop1
OUT loop1 -> IN loop2
Send loop2 -> IN Roadster
FX Send Roadster -> Return loop2
OUT loop2 -> IN GForce
OUT Gforce -> FX Return Roadster ..

and Im having a gound loop hum !! when the I plug the jack in the IN of the roadster
I have tried many things.
I remove the ground of the triaxis it reduce the hum but it still there.
I have tried a Hum eliminator Ebtech nothing change

I have spoke a very cool tech in voodoolab
and we have tried many things and options
he advises me the hum eliminator
but nothing change

does anybody have the same config ? has anybody had the same problem ?
a solution for me ??

 

[R_ADKINS80]

I don't think what you are trying to do is possible without running a true stereo rig. Meaning: If you want to run the Triaxis with the Roadster then you need to run the Triaxis with its own poweramp and speaker cabinet, NOT try to run it through the Roadster while trying to use the Roadster's preamp at the same time.

Or you could do it the noob way that my buddy ran an ADA MP 1 back in the day. His amp did not have an fx loop so he set it to the clean channel and ran the ADA through the guitar input of the amp. While not technically correct......it worked.

 

[reuveu]

no no I don't want to run both at the same time
but to be able to choose either the triaxis or the preamp section of the roadster

i.e
i choose loop 1 i run the triaxis within the roadster poweramp
i choose loop 2 i run the head normally
never both at the same time ...

 

[R_ADKINS80]

Well alrighty then....disreguard my comment, as it is still early here in the US and I am still sleepy lol. I misinterpretted your post completely lol.

 

[phil110567]

Hi Guys,

I have recently bought a Triaxis V1 which I plugg into a Roadster head as poweramp
The sound is diabolic but I wanted to use both preamp (i.i Roadster and Triaxis)
Therefore I bought a GCX which is control with a Ground Control

the schema is the following
Guitar -> IN GCX
OUT GCX -> IN Loop1
Send loop1 -> IN Triaxis
Output Triaxis -> Return loop1
OUT loop1 -> IN loop2
Send loop2 -> IN Roadster
FX Send Roadster -> Return loop2
OUT loop2 -> IN GForce
OUT Gforce -> FX Return Roadster ..

and Im having a gound loop hum !! when the I plug the jack in the IN of the roadster
I have tried many things.
I remove the ground of the triaxis it reduce the hum but it still there.
I have tried a Hum eliminator Ebtech nothing change

I have spoke a very cool tech in voodoolab
and we have tried many things and options
he advises me the hum eliminator
but nothing change

does anybody have the same config ? has anybody had the same problem ?
a solution for me ??

Hi !

I've already had a ground loop problem with a GCX (but the configuration was not identical : no additionnal preamp, only pedals in loops)...

I've solved it by using a very special A/B box : "crossroads" by Roger Mayer. This A/B box has an isolated output. It does not change tone but it removed my ground loop problem (in this case I don't even use the A/B feature, only the isolated output.
I just plug the output from GCX into this pedal and I choose the "A" side which is isolated.
It means there's no electrical connectivity anymore so the loop is gone.

There are many "isolation" devices like those made by Palmer.

I hope it helps...

PS : Salut, je suis Français, j'habite et je travaille à Luxembourg et je joue sur un RoadKing

 

[reuveu]

in fact i just want to try to do like
several preamps in a poweramp

except that a preamp and the poweramp is a head

I have try the ebtech by morley hum eliminator 2
but the hum still there ...

PS je suis francais, jhabite Metz et travaille o luxembourg et je joue sur un triaxis et une roadster avec une p...*&*&^* de boucle de masse. !!!

 

[phil110567]

I do understand your problem.

Please find below some information about the roger mayer crossroads which is actually an A/B box but of a special kind.
As you can read, the output A is "transformer balanced" which means that there are no actual connection but you have a transformer instead. The ground is not connected but in a safe way. As the 2 devices are not connected anymore, you can't have a loop. I'm not sure the Morley stuff is "transformer balanced".


Extract from documentation of the crossroads :
The two switching modes are made much more flexible and have many more advantages by the fact that Output A is transformer balanced. The type of transformer that we use is manufactured from the latest high performance wideband ferrite material and is audibly transparent with a frequency response that extends to over 100KHz. It is very important to have one of the outputs balanced because in many cases when connecting several devices together in parallel a ground loop is formed causing hum and interference.

 

[reuveu]

yop the morley stuff is balanced lines

extract from website
"The Hum Eliminator™ is designed to eliminate 60 cycle hum (60Hz AC signal) caused by Ground Loops.
It is also designed to convert unbalanced lines to a true balanced lines (and vice versa). Why?
Unbalanced lines are more susceptable to picking up electrical noise and RF interference. "

 

[phil110567]

Please, be aware that it must be isolated by a transformer.
I'm not sure the morley works with a transformer

Please, have a look to the palmer stuff which does the same as the Roger Mayer's without the A/B switching :

http://www.palmer-germany.com/41-2-pli01.html

You may notice here that the focus is on the transformer which is used in theses boxes that actualy isolate the output from the input.

Hope it can help

 

[MrMarkIII]

Use the Ebtech on the Roadster A/C only, not the power strip for all your gear.
Or, try disconnecting the shield (ground) from ONE end of ONE of your many cables hooking this stuff together. Any cable but the first one from your guitar.

 

[reuveu]

Yop Guys,

after a lot of tests and time to do the troubleshooting :evil:
The ground loop 'has gone'

here is the solution
Guitar -> GUITAR IN GCX

GUITAR OUT GCX - > IN Triaxis
FEED THRU OUT GCX - > IN Hum Eliminator
OUT Hum eliminator - > IN Roadster

OUT Triaxis -> IN Loop 1 GCX
OUT FX Send Roadster -> Return Loop 1 GCX

OUT Loop 1 GCX -> IN GForce
OUT GForce - > FX Return Roadster

with this config
- when loop 1 is ON the sound comes from the Roadster
- when loop 1 is OFF the sound comes from the Triaxis

and with this schema the ground loop disappeared ...
just need to do the set up of sounds now !!

 

[phil110567]

Congratulation !

I'm planning to do almost the same with my studio preamp...

Do you have a band in metz ?
what kind of music do you play ?

 

[reuveu]

no band
I tried to find something few years ago but most of the musiciens around metz i found wanted to do a lot of rehearsal and play maximum of tour dates
even it is cool to play live, I just want to play for pleasure and have fun

I play Rock, metal Prog ... Dream theater, Rush ...
i don't play in a regular way .. when the day is sunny the call of the motorbike is stronger