Topic: M32 DA/AD PRO, Heat And Noise Question

I got a new M32 AD/DA PRO System, and as i hooked them both up, they startet Ventilation about half an hour later. The processors of the units went up to 74 on the one and 69 Degrees on the other unit, without sending any Audio signal through.  They feel very hot from the outside as well. They were connected to my UFX+ by MADI.

I just want to ask if this is kind of normal, and if there is any solution for less fan noise, maybe adjustable RPM or turning them off temporary for Mic-Recordings.

These M32 units are really amazing pieces ofi Hardware and I love them already, but this issue would be great to fix, if possible.

Thank you.

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Re: M32 DA/AD PRO, Heat And Noise Question

32 channels plus network processing in a 1U height enclosure won't work fan-less. You can reduce upheating by making sure the enclosure has free space around it, either by using higher feet, or leaving a bit space to other units within a rack.

BTW, there is a firmware update on our website's download section.

Regards
Matthias Carstens
RME

Re: M32 DA/AD PRO, Heat And Noise Question

Thank you.

Yes I saw the update and installed it. I am already leaving space between the units, and was wondering about the heat with no audio floating through it, but I think that staying in sync needs to be calculated by the processor, even there is no signal, right? I just want to understand;) Btw. The UFX+ is processing a lot more audio in my case.

I don't know how hot it can get but is there a thought about more manual control on the fan in further updates?

I think the  M16 AD/DA is without a fan, is this right?

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Re: M32 DA/AD PRO, Heat And Noise Question

Audio or not does not change the power consumption significantly.

I will ask about manual control.

The M16 has no network processing, half the channels and double the enclosure size - then it works without a fan  wink

Regards
Matthias Carstens
RME

Re: M32 DA/AD PRO, Heat And Noise Question

The M-32 Pros are getting quite hot due to the following design decisions:
- true balanced circuitry, involving 4 op amps per channel
- line level of +24 dBu, which require analog voltages of +/- 15V
These on the other hand are among the most important features of this series, so we didn't want to make any trade-offs there.
Moreover, as MC already mentioned, about 20% of power consumption stems from the network processing engine (which also provides other features and cannot be turned off).
The fan is therefore required to stay within the specified temperature range of all parts.

However, during development, we did intensive testing in case of fan failure. We found that even if the processor temperature went up well beyond the specified limit, the unit continued stable operation over many hours.

Of course we cannot and will not recommend that. Thermal design of rack units is tricky, there are countless scenarios where the units could be installed. So if we add an additional "fan off" mode, it will have be a "we take no responsibility whatsoever and you are required to monitor the temperatures on your own"-mode.

Let me discuss that within our team, let's see what we can do.

Re: M32 DA/AD PRO, Heat And Noise Question

Thank MC and Marc,

@MC you are right of course: choosing an M16 for fan only feels like living in the past, and not so good;)
Maybe a second UFX+ with less IN/Out then, is an option, if the fan noise is annoying too much, just thinking...any other thoughts?

@Marc:
I got that and it totally makes sense.
But it would be great to turn them off for recording, otherwise I think it can be an issue in some studios.

I was thinking about a "fan-off timer" that turns it off for 30 minutes or a specific time range, so you can't forget about that.
Or deactivating the fan with a "critical threshhold value", where the fan necessary has to start again to avoid damage.

Maybe choosing manually fan speeds can be a big advantage, as you watch the temperature and get your workaround with that, if lower RPM-values are doing almost the same in your setup.
For me It feels like the fan is not regulating that much for the action it does, but I can only compare to running with no fan, so its just a non-objective opinion on that point;)

Re: M32 DA/AD PRO, Heat And Noise Question

Please note that it is a bit of a contradiction to build a super low noise design and then add a fan, at least in case the device is running in the same room where monitoring or recording takes place - and yes, there are many nice applications for these devices just in such rooms.
So I support requests for reliable non-fan mode. Not possible to partly reduce functionality in order to reduce power consumption? Can an alternative housing (e.g. with many vents) help?

Re: M32 DA/AD PRO, Heat And Noise Question

I was always interested about M Pro series with heat and fans but decided to wait out and watch.  I totally get that they are designed for more broadcast scenarios that imply machine rooms etc.  For the time being the Micstasy/ADI8-QS combo is still quite a high spec and silent combo.  What it loses in perceived quality in comparision to M Pro or later Focusrite Rednet I cannot say as I have never compared.  But at least in my situation the only time I ever wrinkled my nose at the RME was the (utilitarian) Madiface XT headphone DAC vs Merging Hapi, when switching from one to the other.  In the true actual pre/adc/dac dept, I am still very happy.

Madiface XT, Madiface, 3x Micstasy, ADI8QS
Sequoia 14,  W7Px64, W10Px64

Re: M32 DA/AD PRO, Heat And Noise Question

Yes, it's true, the ADI 8 QS works without fans and noises, but we should not forget it's now a 12-year-old product.

Re: M32 DA/AD PRO, Heat And Noise Question

Ulrich wrote:

Please note that it is a bit of a contradiction to build a super low noise design and then add a fan, at least in case the device is running in the same room where monitoring or recording takes place - and yes, there are many nice applications for these devices just in such rooms.
So I support requests for reliable non-fan mode. Not possible to partly reduce functionality in order to reduce power consumption? Can an alternative housing (e.g. with many vents) help?


Yes I Think the same. Maybe kind of a "power sheme" is a good point, where the Units run in minimal mode like 16 Channels only, no Network for example. I think right now there is nothing comparable on the market. The sound quality is outstanding in my opinion and switching (back) to an 12 year old device is no proper solution because of ventilation;)

@Matthias, maybe you also can come up with this approach, beside the "manual control"- idea, when you're talking with RME guys;)

Re: M32 DA/AD PRO, Heat And Noise Question

just want to let you know that there will be a new firmware, that has new power schemes!

They did that really fast and efficiently, and the beta version I tested worked very good!
I can’t say anything about the schedule of the release of this new fw, but I think it will not last very long..

Re: M32 DA/AD PRO, Heat And Noise Question

Interesting! I hope we will get more information here on the new functions and their impact on noise generation.

Re: M32 DA/AD PRO, Heat And Noise Question

As Lutz said, there's a new firmware release in the pipeline. Thanks Lutz for testing the beta version and providing feedback!

The official release will be around next week, but for anyone who wants to give it a try now, here is a link to the beta firmwares (AD and DA):
http://rme-audio.de/download/m32_v1.2.2-beta1.zip

In this version we added another fan preset, named "Off", where the fan stays off (obviously) until a critical temperature (71 deg C in the analog section) is reached. Only then it starts at mid speed, but going up quite fast.
This new profile is intended for situations where there is enough space and airflow *around* the unit. Our tests have shown, that leaving about 1 HE space to each side is a good number (the more the better). Setting the frontpanel led mode to "Dim" additionally lowers power consumption and with that heat dissipation.

Secondly, the "Silent" profile has been optimized and renamed to "Normal". Now the fan starts from the very beginning at lowest speed possible and turns up slowly if temperature rises.

Re: M32 DA/AD PRO, Heat And Noise Question

Cool, I had the M32 AD pro with the new Firmware run for 90 minutes in a ful lrack without spacing in-between without the fan turned on. It works just fine. Thank you!

Re: M32 DA/AD PRO, Heat And Noise Question

strange fact on the side: After 90 Minutes I turned the fan on (cool mode). Now 10 minutes later the processor is still at 72 degrees and analog still at 58 degrees... so no change at all?

Re: M32 DA/AD PRO, Heat And Noise Question

Due to it's mechanical design and PCB stackup, thermal mass is quite high. This in turn means temperature is both in- and decreasing rather slowly.
Environmental temperature is also an important factor. The "Cool" preset is primarily meant to be used in air conditioned machine rooms, where the fan ensures proper air exchange in densely packed racks. It's not very effective if environmental temperature is too high (more space between units is the way to go in these circumstances).

In your case, 58 and 72 degrees still leave enough safety margin, so no worries. How high were the temperatures when you've switched presets? What was the environmental temperature and how much space did you leave between units?

Re: M32 DA/AD PRO, Heat And Noise Question

Hi Marc,
thank you for the reply. Unfortunately I don't have any space between the M32pro and the preamps :-(
(this is our mobile recording rack: on top Furman, next RME, next 2 x DAV BG8 preamps, in a separate Rack 2 x Millennia HV3r)
It was very warm that day. I would say at least 35 degrees (environment). As I mentioned: When I switched the presets the temperature was 58 degrees (processor) and 72 degrees (analog). This stayed the same when I switched the presets from "off" to "cool". Even after 30 minutes there was still the same temperature.
Neertheless: I thought the setting "cool" is meant to keep the M32pro as cool as possible smile
--> Thank you for clarifying this. smile
Marcus

Re: M32 DA/AD PRO, Heat And Noise Question

Hi Marcus,

mruebsamen wrote:

Unfortunately I don't have any space between the M32pro and the preamps :-(
(this is our mobile recording rack: on top Furman, next RME, next 2 x DAV BG8 preamps...

I see. With no space at all there is the possibility that the fan could finally start spinning (above 70 degrees analog temperature). Are you using the rack in "no noise"-environments like classical recordings on stage?
Otherwise you could place a slow spinning large fan (>12cm) at the back of the rack, so that it blows between Furman, M-32 and upper BG8. This is immensely effective, as heat is transported away from the chassis (which works as a heat spreader).
If fan noise is a no go, than you could try swapping the lower BG8 and the M-32.

mruebsamen wrote:

Even after 30 minutes there was still the same temperature.
Neertheless: I thought the setting "cool" is meant to keep the M32pro as cool as possible smile
Marcus

Well, it is "as cool as possible" quite literally. In a packed rack, given high environmental temperature, holding the temperature at 58 degrees (you've written processor, but I guess you meant analog?) is hard enough. The temperature would surely have increased otherwise. But still, lot's of safety margin in your case. No need to worry so far!

Re: M32 DA/AD PRO, Heat And Noise Question

Hi Marc,

I see. With no space at all there is the possibility that the fan could finally start spinning (above 70 degrees analog temperature). Are you using the rack in "no noise"-environments like classical recordings on stage?

No... Even though there is "no noise on stage"  the rack is far enough. So that we haven't had  any real issues yet (even though I could hear it :-/

Otherwise you could place a slow spinning large fan (>12cm) at the back of the rack, so that it blows between Furman, M-32 and upper BG8. This is immensely effective, as heat is transported away from the chassis (which works as a heat spreader).
If fan noise is a no go, than you could try swapping the lower BG8 and the M-32.

I try to do this. Thank you for the good tip. However, I was really happy about the new "no fan" mode. It worked for me for a long time. We are recording typically in large cathedrals in which the temperature is not that hot. Next Sunday we a have a two hours recording at the Freiburger Münster. I keep you posted smile

Well, it is "as cool as possible" quite literally. In a packed rack, given high environmental temperature, holding the temperature at 58 degrees (you've written processor, but I guess you meant analog?)

I'm not in the studio at the moment. But I'm pretty sure, that the "setup page" displayed 52 degrees for the processor and about 70 degrees for the analog section....
Thanks again and best regards, Marcus