Damn Neon Lights!!

[SteveC]

We played a gig last night at a bar that has about a million neon lights. The buzz through my amp was driving me crazy.

 

Are there any products you can plug into the wall before you plug in your stuff that will filter that crap out?

[Fred TBP]

Last time that happened to a band I was in, my soundguy dragged out this HUGE 200-foot cable with clamps and tapped directly into the breaker box (secondary lines off the transformer) of the club to bypass all the lights.

 

The "simpler" solution is to get one of those power regulating units from Furman or Tripp-Lite that go for around $400 and have triple-level surge protection on them, but I discovered they're also succeptible to interference from computers (noisy peripherals like older hard drives) so that's not a guaranteed solution.

 

Of course, you could run a huge extension cord out onto the nearest utility pole and tap into that; some of them have 110V/220V outlets, but be sure you know what you're doing, and be advised it could get you arrested depending on whose property the pole is providing power to. Not to mention it could fry your amps if done incorrectly.

 

Reminds me of a camping trip I took with some musicians where we did tap into a utility pole on the campgrounds, but the ranger cut us off because of the noise, not because we were tapping into the pole.

[g.]

What you would want is not called a power regulator (mentioning this because simple surge protectors with light shows have been called this). But indeed, Furman and Tripp-Lite and others have supplied line conditioners which are basically isolating AC via an auto-tapping transformer that also keeps voltage within a few percent as long as sufficient power is available at the receptacle.

 

That'll only go so, far though. It helps to have all audio on stage star grounded through one circuit (that means every amplifier running from the same point, on fat wire and heavy duty receptacle), and have you shielded your bass to a higher level? I've posted about that recently in some Fender thread, and elsewhere in the past.

 

Still, lights on "starters" and dimmers can be a problem if on the same circuit as audio or in proximity; when I play clubs with beer signs on stage we usally unplug as many as we can get aay with.

[jeremy c]

Last time I had that problem, I used a noise gate.

 

It was the at the Flamingo Lounge.....the stage was surrounded with pink neon lights. There were also dimmer switches for the spotlights, everything was on the same circuit, and it was a complete nightmare for all our equipment. I have the highest-tech gear in the band so naturally my equipment buzzed the most.

[ArwinH]

Would an ebtech hum eliminator work?

[g.]

If that's the box I'm thinking (Peavey and others have made them too), using one will merely make sure that at that point in a signal chain there is no ground loop.

 

I did mention ground loop prevention in that other post, but as concerns not one component - but rahter the entire stage setup and PA. Also, it was mentioned more in the spirit of eliminating multiple paths for interference/noise, and to GET OFF any circuits with lighting dimmers and starters.

[way2fat]

I looked at one of those Tripplite voltage regulators, but the one with enough capacity had a 20 amp plug, the one with the neutral blade perpendicular to the hot one. I never see those recepticles where we play, unfortunately. I have also heard that "stacking" surge protectors doesn't increase surge protection. Is this true? What would be the best approach to take in a real world bar venue? Unplugging everything possible? Are any surge protectors commonly available more than junk?

[g.]

You've got a DPC amp don't you? You could use the 15-amp version as a personal rig protector - though really, that's suited for gigs where the club has crappy wiring add-ons and poor service - it'll keep you rocking without damaging YOUR gear during overvoltage or cicuit brownout. Also great for generator gigs, PA subsystems, anything with DSPs or more sensitive electronics in it, etc.

 

Doesn't work for "lead sled" power amps. As it is, some clubs actually won't allow a lead sled to develop full output power because it gets starved of input power and its conversion is not very efficient.

 

I mentioned star grounding a few posts ago, that's the way to get an entire band's audio set up. You go off one strong circuit for all audio gear - it all leads to that one AC source. Same as done in good studios, though for studios it is done with even more thorough means.

[way2fat]

Thanks for the info.

[way2fat]

Actually I'm running a Stewart 1.6 right now, the DPC-1000 was the one I let the smoke out of bridging into a Whappo Jr. It's at Peavey seeking a rebuild if it's not prohibitively expensive.

[Eric VB]

Oh, I thought Steve just wanted to know how to hook up those purple lights that people install under their cars to his bass rig. You know, the ol' "How do I plug 12VDC into 110VAC?" question.

 

[jeremy c]

Surge protectors will protect your gear from....surges.

 

Some of them may filter out some noise.

 

But they are not a cure-all.

 

Some surge protectors have fancy readouts that tell you what the voltage is. But even the most expensive product that Furman makes (which is called a voltage regular not a surge protector) can only help if the voltage is higher than 97.

 

Some 60 cycle hum (or I suppose 50 cycle in Europe) can be filtered out but getting rid of huge amounts of rf interference which is what you are getting from the dimmer switches and fluorescent lights is not easy. You will also get this kind of noise from computer monitors and other kinds of peripherals.

 

I've tried all kinds of things to filter out rf interference including shielding (with star grounding) and ferrite beads.

 

So my solution in the kind of extreme cases we are talking about is to use a noise gate.

 

I like the suggestion of using a 100 foot cord and connecting to a power source in another room. But this unfortunately is not always practical or possible.

[g.]

way2,

 

Ah, yeah. Well, for that Stew I don't recall it's input requirements (often silkscreened on back, definitely in the manual), but it might be at the edge of a 15 amp line conditioner's ability. What's it say back there? ; }

[g.]

Sure, a noise gate can help. Use one all the time as part of V-Bass presets - set never higher than that preset requires. Actually the downward noise expander as found in a Hush unit or as part of a Rane DC24 is a less destructive type of noise reduction than a hard gate. Doesn't cut off note decays so obviously if noise is present.

 

What IS valuable about an actual line conditioner {haven't I typed this before?;} is that it also provides power isolation.

 

Still, the key factor maybe also mentioned is to get all band/SR audio off any circuit with light dimmers and starters.

 

And shield that bass decently; hardly any factory basses or even a lot of luthier jobs are done fully.

[Eric VB]

Originally posted by jeremy c:

So my solution in the kind of extreme cases we are talking about is to use a noise gate.

Is that like a "notch filter" centered on 60Hz? How wide is the notch? You've got A1# @ 58.3Hz and B1 @ 61.7Hz ... as long as you're dealing with 60 +/- 1.6Hz power you should be able to use a 3.2Hz wide notch. Oh, and as long as you're not sliding through those pitches, too, otherwise there'll be a noticeable drop out, right? (I have a feeling this isn't practical.)

[g.]

Noise gates commonly are used to "gate" mics below a certain settable threshold, on stage and in studio. When sufficient signal is present the gate opens and lets the signal through until its amplitude again falls beneath threshold. The gated [reverb] kick and snare drum sound popular during the '80's used a high gate setting to truncate decays.

 

Downward noise expansion is more musical and can really clean up a mix. It too has a threshold,m but also a ratio. All signal below the threshold is moved down in dB according to the ratio one has set - in effect the reverse of compression. But actually it's often used with compression since compression brings up the noise floor.

 

The Rane DC24 puts all that and a peak limiter in a two channel package along with a crossover that can send out two different bands, or be recombined internally, so that each band may be treated differently. Or it can be used as two mono units or for stereo signals.

[g.]

In general notching is a poor approach for 60-cycle noise/hum since that noise also exhibits harmonics. Notching is better for control of acoustic body feedback and general PA feedback, and a whole crapload (tech. term) of self-sensing self-adjusting variable-depth notch filters are what you find in a good SR feedback eliminator, usually done in DSP.

[Eric VB]

Ah, based on signal strength. Gotcha. That DC24 sounds pretty sweet, even if it doesn't fly to Chicago.

 

No fancy schmancy FFT routine to isolate that hum? Sheesh!

 

How about a 60Hz low-pass filter? You'd only have to string your 5-stringer with B and E strings, and you'd have a full set of 12 chromatic pitches to work with!

 

You could go the other way with a 60Hz high-pass filter. That would leave you with exactly 5 chromatic pitches all to yourself before you run into the g****r's low E string. And if you need a cap for this, your amp may have some extras just sitting around in epoxy.

[jeremy c]

Greenboy already explained what a gate is but here it is in less technical terms.

 

An equalizer or notch filter or highpass filter can be used to reduce the volume level of frequencies.

 

A gate can be set to cut all sounds below a certain volume level. If the buzzing is softer than the notes you play, you can set the gate to only let the notes through.

 

However, it will play havoc with the decay of notes...when the notes fade to the level at which the gate is set, they will simply disappear rather than continue to fade.

 

Gated mikes on drums were used to get the sound of drums ringing off of recordings and they gave a distinctive sound to a drum set while doing it. The practice seems to have decreased in popularity.

[SteveC]

So I guess when there are a lot of lights, it's just gonna suck a bit, huh?

[way2fat]

GB - The only spec. I see is 120V 60Hz 5.25A. I don't use any effects so it would just be the pre-amp and power amp plugged in to it. Are all the major brands about the same at the same price for regulators?

[g.]

way2,

 

Nothing in the manual about its gulping habits during full load, or say 2x4 ohms fully driven? Assuming 5.25 is its draw in such a case, it should be fine.

 

I haven't priced them for awhile, but last time I did TrippLite seemed to be at a great price. Actually that was for a non-rack version -- you pay a premium for a rack version, and I found it easier just to throw a regular block version into the back of the rack on top of the closed cell foam I place between rack and cab. Without wasting a rack space.

[way2fat]

There might be, but I only refer to manuals as a last resort.