Voodoo Lab

Hi all,
i own a Voodoo Lab/DMC System Mix Plus and would like to use the VCA before my amplifier input to simulate the volume pot on my guitar.

In the manual it says it's designed for line levels, so i'm guessing this is why when i wired it up, i experienced all kinds of hell in hissing and noise!!

I looked on the site but couldn't find anything, so i thought I'd ask here, does Voodoo Lab have any sort of signal converter(??) for this type of problem?

Cheers and thanks!

Bump?

The best signal to noise ratio is going to be at line level. The VCA will likely add some hiss when routed in front of an amp, however I would think this would only be noted when using a ton of gain. Simplify the setup as much as possible to determine if there is possibly another reason for the problem.

Hi john,
i'm using a krank revolution with the gain almost maxed out.
just tried these various scenarios this morning.

1) GTR -> AMP.
2) GTR -> VCA -> AMP.
3) GTR -> VCA -> NS-2 -> AMP.
4) GTR -> AMP -> VCA (fx loop).

1) GTR -> AMP.
normal pickup noise. rolled my volume dial back to get rid of pickup noise. a little high end hiss, but that's always been there. my amp sounded normal.

2) GTR -> VCA -> AMP.
buzzing is introduced. rolling volume dial up or down does nothing to change this.

3) GTR -> VCA -> NS-2 -> AMP.
even with the NS-2 maxed out, the buzzing is audible. it IS reduced some, but still way too present. i tried some different cables, removed the NS-2, did all variations.. buzz is always present.

The only time the buzzing is not present is when the VCA OUTPUT is disconnected from the next device in the signal chain.

4) GTR -> AMP -> VCA (fx loop)
No buzz, so it's not the VCA itself or an electrical problem.

would this LLS-2 http://www.ebtechaudio.com/llsdes.html be the right device to remove the noise i'm experiencing?

I didn't realize this was a loud buzz rather than some added hiss. Likely what you have is a ground loop. Simplify the setup as you have done but isolate things from touching common conductive surfaces. In the case where you had the guitar to VCA, and VCA to the amp, was anything else connected to the System Mix Plus or to the amp? Only when you find the source of the problem can you apply the fix so lets first find the problem.

Hi john.
yeah, i hadn't realised it was such an obnoxious buzzing noise either until yesterday.. this is going to be a very long post so get your coffee ready!

In the case where you had the guitar to VCA, and VCA to the amp, was anything else connected to the System Mix Plus or to the amp?

Yes.
Normally i plug my Krank send into DBX channel A in, and the DBX channel B out goes to the Krank's return. Yesterday, everything else was still set up in my rack as per usual, except the cables were detached from the send and return jacks on my amp.



So today i disconnected EVERYTHING from the SM+ and plugged my guitar into the VCA then the VCA into the amp input. A lot of high end hiss, but no buzz(!!!)

When made a connection between the IPS33B and the SM+, a slight hum returned so i kept the IPS33B disconnected (i've noticed a very loud vibration inside the IPS33B whenever it's switched on.. bad power inside it?)

Upon making a connection between the SM+ and the G Major, no buzzing but a very high pitched frequency became very slightly audible, so i disconnected the G Major again.

Plugged the DBX266XL Channel A output into the System Mix Plus MIX 1 IN 1 as i normally would. That's where the buzzing was at it's worst. Changed cables, unplugged different things from my Furman power conditioner, there was no change.

I run the DBX off a 240v AC power board (240v AC, i'm in australia) and nothing else on the power board (whammy, midi pedal) has ever given me any problems. When the VCA is not in my signal path, the DBX has never given me any problems either, and it sounds amazing.

All of the other equipment is run off 110v as i own a fair bit of vintage american gear.
I use a 240v AC -> 110v AC stepdown transformer, which powers a Furman PL plus power distributor. My Krank, System Mix Plus, IPS33B, G Major, and an old rackmount MXR Flanger are powered off the Furman. Also, a 9v DC adaptor is plugged into it, and that powers a DMC/Voodoo Lab MX28S midi splitter/distributor.

I intend to get a US DBX model (110v) so i can power it from the furman, but i haven't had the money to order it over.. having said that, i wouldn't think the buzzing is caused from the 240v/110v because, as i mentioned, i've never had any problems from the DBX running off 240v, it's just whenever the DBX and VCA are patched into the signal together, something goes haywire!!

What do you suggest John?