Hello all, first time here so please be gentle! 😀
I wasn't sure exactly what board to put this on
Anyway I am running across an issue that is driving me nuts. Live situation. I play a LP through some pedals and then a Radial Pro48 Active DI which splits off to my Vox AC10 and XLR to house PA. I get a nasty hum even with ground lift on the DI. I also picked up a HumX and have my AMP power going into it. Still same hum. I moved the humX to the power of my pedals (MXR ISO brick) but still same hum.
The only time the hum goes away from amp and PA is when I disconnect XLR from my DI. I don't have access to get into the PA other than plug in and set level.
Do you guys have some ideas to get around the hum? I use my amp to help me monitor my sound and need PA to reach the audience.
David
I wasn't sure exactly what board to put this on
Anyway I am running across an issue that is driving me nuts. Live situation. I play a LP through some pedals and then a Radial Pro48 Active DI which splits off to my Vox AC10 and XLR to house PA. I get a nasty hum even with ground lift on the DI. I also picked up a HumX and have my AMP power going into it. Still same hum. I moved the humX to the power of my pedals (MXR ISO brick) but still same hum.
The only time the hum goes away from amp and PA is when I disconnect XLR from my DI. I don't have access to get into the PA other than plug in and set level.
Do you guys have some ideas to get around the hum? I use my amp to help me monitor my sound and need PA to reach the audience.
David
Are You playing Vinyl ?
Are You aware You need to connect the Turntable to a pre-amplifier before the pedals ?
David,
The Radial Pro48 Active DI does not use transformer isolation, unfortunately there are some combinations of equipment where transformer isolation may be the only way to prevent hum. Radial's passive DIs all have transformer isolation.
A DI "ground lift" disconnects pin 1, the shield connection of the XLR connector.
That normally eliminates the hum inducing "ground loop" that can occur between the mixing console's ground and your stage amplifier's equipment ground.
If the XLR has been wired with the shield connected to it's case as well as pin 1, the shield will remain connected, no "ground lift" regardless of the switch position. Most XLR's shields are not connected to the case, but some are- check continuity between pin 1 and case with an ohmeter, if it reads a few ohms, you likely have found the problem. That said, there may be only one XLR cord out of dozens in a sound system that are (mis)wired in the above fashion, unless they all happened to be purchased in one lot.
That said, the sound of a guitar amp and speaker are as much a part of the sound as the pedals and guitar (Les Paul?), using a microphone on the Vox AC10 would eliminate any ground loop problem, and allow the sound engineer and audience to hear what you play on stage.
Art
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The Behringer DI-100 DI box (active) claims to offer Galvanic isolation. I poked around on one with a meter, and it appears to be true, even when running from phantom power.
Yeah, yeah, it's a Behringer. Not up there with your Radial DI. But might be worth a try? For the price of them it cant hurt, and if it is no good you can always throw it at your bass player..... 😀
Ant.
Hey guys, I appreciate the responses!
By LP I meant a Les Paul guitar, my bad. No DJ here 😀
I had a feeling that since I was getting phantom power from the mixer, that would be the source of Ground Hum. I ordered a Whirlwind IMP2 to see if going passive is the key. I'll keep you posted!
I could also test the cable. I think I have another lying around to see if there is a difference.
You're right about micing the amp. I was just trying to keep things "simple" but at the cost of my sound. Ugh. It sucks because I don't have alot of time for setup. I need to be able to plug in and be ready to go. No house engineer available to help adjust things.
By LP I meant a Les Paul guitar, my bad. No DJ here 😀
I had a feeling that since I was getting phantom power from the mixer, that would be the source of Ground Hum. I ordered a Whirlwind IMP2 to see if going passive is the key. I'll keep you posted!
I could also test the cable. I think I have another lying around to see if there is a difference.
You're right about micing the amp. I was just trying to keep things "simple" but at the cost of my sound. Ugh. It sucks because I don't have alot of time for setup. I need to be able to plug in and be ready to go. No house engineer available to help adjust things.
Going passive DI might be OK if your pedals are buffered. But if your pedals are true bypass, or you otherwise end up with guitar directly into the passive DI, you might find you lose a chunk of top end off your guitar signal.
I'd think mic'ing your amp is your best alternative. No ground loops there, and it's always going to work into any mixing console.
Or a true galvanic isolating active DI, if you're dead set on that.
FWIW, I have always mic'ed my guitar rig. As said earlier in the thread, the amp and speaker is an integral part of most guitarists tone; a DI of course misses all of that.
Ant.
I'd think mic'ing your amp is your best alternative. No ground loops there, and it's always going to work into any mixing console.
Or a true galvanic isolating active DI, if you're dead set on that.
FWIW, I have always mic'ed my guitar rig. As said earlier in the thread, the amp and speaker is an integral part of most guitarists tone; a DI of course misses all of that.
Ant.
Buy a ISOBLOX Transformer Isolation 1:1 or similar. Amazon $27.99 and add to XLR Cable to the house feed.
Duke