Dimmer for Lowel Omni

M

majeure

New member
I'm still looking for a dimmer that doesn't sound like a sex toy. The buzzing from the vibrating filament makes recording clean dialogue impossible.

I tried one made for household fixtures and it buzzed WAY too much, then tried this one from Barn Door :http://www.filmandvideolighting.com/10vadi.html
and got the same result.

I'll build one if I have to, but I'd rather just buy it.

Thanks!
 
I have read the previous posts and it looks like the dimmer from Habour Freight is the same one sold by Barn Door, so I'm looking for some alternative here.
 
Hi Majeure,

FYI, I tried a few noise tests - here's the results.

Setup:
Light -> Harbor Freight Dimmer -> Watt Meter
Monitor: Sound Meter

With a Lowel Pro (150W), the light doesn't make any noise regardless of the intensity.

With a Lowel DP (1000W), indeed the light has a subdued buzz - about 20 dB lower than speaking level (-42 dB on the sound meter, placed 3 inches from the light). The vibrating noise seemed to be fairly constant adjusting the dimmer anywhere from around 600W down to 150W (the lowest dimmer setting).

I didn't try my Omni, but me recollection is that it's less noisey with the lower wattage load. If it's really important to you, I could do another test and let you know the dB on the sound meter. But actually, even with a sensitive mic that's 6 feet away and a low load from the Omni (like my Oktava MK012A condenser), I don't think the Harbor Freight is audible (and I'm a sticker for good audio). If I did think it was an issue, I'd use one of my lower Omni or Tota wattage bulbs.

Good luck, Michael
 
I believe that sometimes bulbs vary from one bulb to another as far as vibration. I recommend trying another bulb and see if it is quieter.
 
Just spec'd a theatrical lighting system here at work, and I've learned:
the best way to quiet lights is sine-wave-dimming. Most cheap dimmers
slice the AC power sine wave and produce wicked harmonics,
which then contaminate analog audio and makes lamps buzz.
Sine wave dimming, on the other hand, just reduces the amplitude
of the AC power sine wave, so there are no additional harmonics.

Question is: can you get one of these dimmers for a Lowel-sized budget?

Les
 
I use the HF dimmers, I find that they work better with some bulbs than others. Older bulbs tend to buzz more. the worst buzz comes from 500w photo floods, I have a SV with a 600w lamp, same lamp the omnis use with 0 buzz.

good luck.

Jason
 
stuckfootage said:
Just spec'd a theatrical lighting system here at work, and I've learned:
the best way to quiet lights is sine-wave-dimming. Most cheap dimmers
slice the AC power sine wave and produce wicked harmonics,
which then contaminate analog audio and makes lamps buzz.
Sine wave dimming, on the other hand, just reduces the amplitude
of the AC power sine wave, so there are no additional harmonics.

Question is: can you get one of these dimmers for a Lowel-sized budget?

Les
Click to expand...

Hi Les,

My guess is that sine wave dimmers are mostly lower wattage. Generally, it's a no-no to reduce voltage to high-amperage motors, etc., so I'm guessing the target market for sine wave dimmers would be under 1KW. Of course, reducing the voltage for a tungsten light isn't a problem (actually extending the life of the bulb).

For many moons, a variac (variable a/c transformer) has been the ultimate sine wave dimmer, albeit too heavy for filmmakers doing portable work.

Regards, Michael
 
You must log in or register to reply here.
Back
Top