Science-y Stuff Happens Here!
The Sounds of Silence
Maybe I'm spoiled on systems like the F900, Varicam, HVX200, even DSLRs, but I want my camera to be seen, and not heard. In the case of the Epic you usually oscillate between two settings, annoying, and hairdryer. There's a small grace period where your fans won't "sing you the song of their people," but it's a very tiny window, and when you've passed the point of no return be prepared to watch as your sound guy starts grinding his teeth in frustration.
So what's the solution? Well, according to RED and their new fan kit 2.0 setup, it's a new lower fan, and the addition of a top fan. The concept is that by having a bigger fan pushing a larger volume of air, in conjunction with a top fan pulling that air through the cooling duct, that theoretically you'll be able to keep the camera cooler for a longer period of time.
The Ideal
Keep the camera as quiet as possible, for as long as possible. This isn't a crazy request. The benchmark I usually hold up is the Arri Alexa, which has a subtle hum, but has never provoked the question on set of "seriously where is that sound coming from?!" The Alexa is also a bigger camera, with a lot more space for allowing the heat to be dissipated. The Epic is a modular design, and you've got a lot of electronics all crammed together. Simply put: 10 gallons of shit, in a 5 gallon bag.
Yeah Mr. White, Yeah, Science!
Alright, so this isn't that scientific, nor did it involve a Winnebago in the desert. However I tried to use a realistic setting for the test, in this case my apartment, which comes close to simulating a nice middle-ground between studio and location audio. My apartment building has poured concrete walls, ceilings, and floors, and has very little noise to it, other than the occasional rustling from my dog sleeping.
The setup was as follows:
-Epic placed about 3.5' from the ground on my Oconnor tripod.
-Sennheiser 416 placed at various locations (2' and 6' from the camera). 3.5' high.
-Audio recorded on the Tascam HDP2
-Room temperature was a constant 73 degrees.
-Each configuration of the camera was allowed to achieve consistent idle temperatures.
-All record times were 15 minutes.
With that said this audio test represents an unrealistic extreme in physical setup. It's very unlikely that you'd ever willingly aim your microphone at the camera, nor would you do so this close. Also this test only captures the onboard noise from the camera. If I was able to design a more elaborate test I would suggest having speakers placed to simulate spoken dialogue, to best capture how the fan noise was impacting the audio off a boom mic.
However we're not splitting hairs in this test, but rather just looking for perceptible differences in fan configurations.
RED Epic Original Lower Fan
Combined Audio Tests
Fan Kit 2.0
So lets start with the proposed 'ideal.' This involves the new bottom fan, and the new top fan. Camera was allowed to come to its idle temp after 30 minutes. This produced a natural resting state of 43/70. For those not familiar with the Epic the first measurement is the SENSOR temperature, and the second number is the CORE temperature. So in this case the Sensor is 43 degrees, with the Core temp being 70 degrees.
I normally keep my camera in the Quiet Record mode. However I noticed right off the bat this produced a pretty audible noise from the fans. Based on some forum feedback I heard the magic settings were to go with Adaptive, and keeping the core temperature at it's highest setting within Adaptive, which was 70 degrees. Once I selected this option the fans seemed to idle down. However the sound was certainly persistent, with the vast majority coming from the lower 2.0 lower fan.
The new lower fan can best be described as whiny, as it has a very noticeable electronic sound to it, that is frankly unpleasant.
I also noticed that engaging the camera into quiet record has NO effect on the lower fan's speed/noise. Whereas with the original 1.0 you'd get an immediate silencing of the internal fan. So with the 2.0 lower fan you can safely say that quiet record has no effect, therefore making adaptive the best choice if you're using the 2.0 lower fan.
The biggest thing to note is that with the 2.0 lower fan and top fan is that you will remain at 43/70 for the entire duration of recording. As mentioned earlier I took two samples, once at the beginning of the record duration, and then another 15 minutes later to see how much the fans may or may not have increased in sound. 15 minutes represents a fairly extreme end of the spectrum as far as record times go.
Bottom Fan 2.0 Only
Okay, this thing is a bigger lower fan. Hell, when you see a Camaro with a hood scope or a blower it just looks faster. So it's a bigger fan, it should be better! Well, not really.
Continuing to use the Adaptive mode (since silent record had no effect on the bottom fan's speed/sound). The same sounds persisted from the earlier combo test. The only difference was that the sensor temp raised one whole degree, holding at 44/70 from Idle, to record from start to finish. Not terribly shocking, since the lack of the top fan reduced the combined efficiency.
Original Bottom Fan (Stock Configuration)
This is the configuration your camera comes in by default. Since the original bottom fan responds properly to Adaptive Preview / Quiet Record, I opted to utilize it since the goal is to create the most silent recording possible, not necessarily the coolest camera.
I ran this test twice, once with the target fan speed set at 40 percent, and the second time set at the extremely low speed of 25 percent. The idle temperature speed using Adaptive Preview / Quiet Record was 45 for the Sensor, and 70 for the Core.
For the first test of 40 percent, the camera was audibly louder in Adaptive Preview. Once the record button was pressed the Epic instantly simmered down to it's silent recording, which while not dead silent, is essentially the epic sipping air for as long as possible. At some point the Epic's core temperature rises to a point where it has to speed up the revolutions of the fan. The temperature at which it does this is 76 degrees, which was uniform across all the tests. At 76 the Epic decides it can't hold its breath and needs to start sucking some sweet O2. The question becomes how long of a time period can the Epic hold it's breath in this Quiet Record mode.
In the case of the 40 percent fan speed the time was 1 minute 57 seconds. The sensor temperature had risen to 48 degrees, with the new core temperature at 76 degrees. It held this temperature for the remainder of recording for the 15 minute test. Fan noise was fairly noticeable for these tests.
For the 25 percent speed test the fans engaged at the 1 minute 50 second mark, with a Sensor temperature at 48 degrees, and a Core temperature of 76.
Original Bottom Fan + Top Fan
Here's where we get tricky. This is the same test as the one previous, with the addition of the top fan. Clearly the original bottom fan has something going for it in the ability to actually shut up in Quiet Record mode. But the limitations are that it can only hold its breath for +/- about 2 minutes depending on the targeted fan speed. The question becomes does the top fan extend that duration between silent recording, and when the fans have to rev up slightly to maintain operation.
Using Adaptive Record / Quiet Preview, the idle speed was a steady temperature of 46/70. The idle sound can best be described as louder than the 2.0 upper/lower combination, but lacking any electronic whining. However once you hit record, things change dramatically.
The camera immediately went quiet, and at 40 percent fan speed the Epic remained in its silent mode for 3 minutes 40 seconds. Only when the core temperature hit 76 degrees, did the lower fan speed up slightly, and it's increase was hardly what I would describe as aggressive. It maintained this sound level, never increasing during the 15 minute record.
The final test was at 25 percent fan speed. Once the record button was pressed the camera went silent, and stayed silent, for 4 minutes 45 seconds. Over a minute longer than the 40 percent speed. And just like the 40 percent test, once the camera did it's initial lower fan speed increase it held that temperature and volume for the entire period of the 15 minute recording duration
RED Top Fan
Final Verdict
So I'll try not to beat around the bush here. Why would you want the lower fan 2.0? Well I think if your goal isn't necessarily silence, but rather avoiding the dreaded hair dryer mode, in locations/environments that are normally not as permissive to Epic's current fan setup.
Outside of that, I can't really think of anything. I've heard some reports, pardon the pun, that there are some lower fans out there that are as silent as the 1.0 fan. In fact on receiving my 2.0 kit I immediately became a little perplexed by the increased noise and electronic whining. This lower fan, used in testing, was sent to RED for examination. Their technicians verified it was working within specification. So if anyone proposes that the lower 2.0 fan in this test was flawed, I can disprove otherwise.
So what's the best setup for those chasing the concept of a quiet camera? To my ears, and equipment it's fairly apparent. It's keeping your 1.0 bottom fan, and adding the Top Fan. In the process of adding the upper fan you extend the Epic's quiet record mode by nearly 250 percent. This is a pretty dramatic increase, and even once the Epic cycles it's lower fan up at the 4 minute 45 second mark, the audio increase is fairly minor. In fact I'd even say the best upgrade for your Epic is just the new fan algorithms if you're on a tight budget!
The information gathered in these tests have given me enough confidence to say that the best combination for your money is the original bottom fan, and new top fan. If RED re-engineers the lower fan to be as silent as the original fan, especially in quiet record mode, while still moving the increased volume of air, then they'd have a winner hands down.
As it stands I think the results are quite deafening.
Top Plate 2.0