Cp950

[Christopher Mondt]

Just bought a CP950 for festival use.
Blulink is nice and working but the fans of the powersupply are as loud as a DOREMI server.
They are real Hurricanes.

Who constructed that?
We measure 82 dB next to the processor.

It is pretty useless to have a soundprocessor in Your rack that makes such noise.
Why include a monitorspeaker if You need earplugs to stand the noise?
Anyone has a solution or same experiece?

Anyone whants to buy the processor from me? (Hamburg , Germany)

Christopher

[Steve Guttag]

You'll find that most places where the sound processor resides to not have a noise issue. Honestly, I don't recall the fan noise to be too over the top and certainly the monitor can play WELL above it. The monitor actually sounds pretty decent (though it doesn't monitor the amplifier outputs, which degrades its value).

I'm wondering if there is something up since you are likely in a 230V country if for some reason that is driving the fans higher. If you want to talk about fan noise, the QSC DPA-Q amps are a bit on the noisy side, as far as amps go. Then again, the Dolby DMA is the real jet airplane when it comes to fans.

[Mike Renlund]

Dolby has had complaints about the fan loudness. We've been collecting thermal information and plan to reduce the fan speeds in the next 1.0.4 version of software. I don't have an ETA on the software at this time.

[Bruce Cloutier]

We have an old DoReMi server back in IT for testing. When we power that up you can tell throughout the whole office practically. The fans are ridiculously loud. Everyone remarks about it and we try to keep the thing off. Thankfully we do not need to test with it all that often. I would think that in this industry where sound quality is so important that nothing should contribute like this to background noise. I get it that cooling is critical. But, you shouldn't have to add soundproofing to the equipment room.

We have a 3-stage air compressor in a closet not far from our IT room. Okay so this compressor was designed to be ultra quiet (for a compressor) and it only runs for some 90 seconds every so often as production uses the air. There is no soundproofing in that closet. When you stand equal distant from the two, I would easily say that the DoReMi is louder. And, it runs for hours sometimes. This compressor is pretty impressive. The DoReMi... not so much.

Cooling is an interesting problem. I have always designed low-power and so I have no cooling expertise. I've been thinking about cranking up our horsepower. But I think passive cooling would still suffice at that point for us.

Equipment for the entertainment industry in my thinking shouldn't have to spec fan noise in dB.

Just saying...

[Steve Guttag]

Bruce, you should remember, projection booths, historically, have not been quiet places. Film machines do make a bit of noise when in operation as do the exhaust when trying to cool upwards of 6KW of xenon based heat. As such, projection booths normally can keep such noises at bay. Just about 100% of those early, HDSDI based servers when into such environments. As such, server (or sound processor) noise is a non-issue. In fact, as we are transitioning to IMB based servers (I say transition because the bulk of our installed base is with SDI based servers though most have been using IMB based servers, for years). Even projectors are getting quieter as we move up the series numbers from 1 to now 4.

[Bruce Cloutier]

Hmm. Good point. It is a bit different in the home theater. My surround amp has cooling fans and it monitors internal temperature modulating the fan speed. You never really hear the fan. Sometimes I wonder if the fan still works. But just because the projector makes noise, you shouldn't disregard sound levels in designing related equipment. Someone might want to use that without the noisy projector.

[Marcel Birgelen]

A lot has been done in the last two or so decades to be able to reduce noise of forced air cooling. Ranging from intelligent fan control to improved fan bearings and improved fan blades. But ultra-quiet cooling technology is usually only used in stuff like high-end desktop PCs or notebooks. The "professional" equipment usually is equipped with the cheapest fans that move the required amount of air.

Usually, I don't have a problem with fan noise in a booth, but those high-pitched tiny, over-driven fans that everybody tends to use nowadays (especially in power supplies) sometimes drive me crazy, as they're especially hard to sound-proof against...

I recently removed a Juniper switch from our equipment rack in the booth of our screening room. When it was working under load, it would emit a high-pitched howling sound that could be heard in the last row of our screening room, even though the wall in-between is almost two feet of just isolation material in multiple layers, ranging from a slab of concrete, rockwool, multiple layers of mass-loaded vinyl and a layer of melamine foam...

[Sean McKinnon]

Personally, I probaly would not buy a cp-950 for festival use. The lack of analog inputs would make it a complete no-go.

We have a custom built "Hush" rack with forced cooling for housing Doremi servers (or any other loud gear) for studio screenings, premieres, or festivals where the projector is installed outside of a traditional booth. It works very well but was not cheap. We also have a custom built "muffler" that attaches to the exhaust ducts of our D-Cinema machines.

[Carsten Kurz]

Fortunately, the more recent systems are a lot quieter. e.g. in our Barco projector, the ICMP (=Server) adds nothing to the noise level. The classic rack mounted servers like Doremi or Dolby DSS were designed to run 24/7 under extreme conditions in densely populated racks, shuffling air into remote parts of the enclosure.
I mean, our 35mm equipment wasn't operating on the low side either.

[Christopher Mondt]

Did Dolby find a solution for the fannoise?

I still would like to sell the new/never used processor.

Christopher (Germany)