Multicore CPUs: Any risk to audio quality?



With the end of the Window XP security updates, among other factors, I needed to take some time to replace my ancient tower pc, possibly with one that runs either an Intel Ivy Bridge 4 or 8 core or the latest Haswell 4 core processor.

To minimize fan and/or electrical noise, the better choice appears to be the low power versions of the Ivy Bridge processor family
(http://en.wikipedia.org/wiki/List_of_Intel_Xeon_microprocessors#Xeon_E5-2xxx_v2_.28dual-processor.29 )
E5-2630 v2 (6 core, 2.6GHz, LGA2011 socket, 80w), E5-2630L v2 (6 core, 2.4GHz, LGA2011 socket, 60w), E5-2428L v2 (8 core, 1.8GHz, LGA1356 socket, 60w)

-or the new Haswell processor family.

http://en.wikipedia.org/wiki/List_of_Intel_Xeon_microprocessors#.22Haswell.22_.2822_nm.29 )
E3-1285L v3 (4 core, 3.1GHz, LGA1150 socket, 65w)

and
( http://en.wikipedia.org/wiki/Intel_Haswell_%28microarchitecture%29#Desktop_processors )
i7-4770S(4 core, 3.1GHz, LGA1150 socket, 65w), and i7-4770R(4 core, 3.2GHz, LGA1150 socket, 65w).

Needless to say, my chief priority will always be audio signal quality (i.e. editing of uncompressed wav files
of music CD tracks for playback via USB or a balanced AES card feeding a high performance external DAC). But I also would like to eventually use this computer for DVD as well as more demanding BluRay movie disc editing.

Though presently having no hands on experience and minimal knowledge of computer video editing, I do know that the most time consuming phase of the process is recompression of the edited video back into the BluRay movie disc format. Depending on the software and hardware resources, recompression could take anywhere from 45 minutes to well over 90 minutes.

So I thought that a new pc with one of the above six or eight core model processors and 16GB of RAM, together with the right software apps, might significantly reduce BD compression time-perhaps to as little as 30 minutes.

Again, however, my primary concern is audio quality. Therefore, compared to the ubiquitous dual core processors, could using four, six or eight core Ivy
Bridge or the new Haswell four core processors somehow pose any degree of risk to audio quality, in one or more ways?

And, of course, of particular interest would be any related incidents involving any of the specific (low power) processors listed above, and/or desktop boards
they were used in.

Before I make this computer purchase, any advice or referrals would be greatly appreciated. Thank you.
ajant
I don't see how a better processor can hurt SQ. If anything, it may help.

If you need a good case, look at the Corsair Obsidian series. They're made very well and designed to be very quiet. I have one and like it very much.
I recently built a quiet quad core Haswell 4771 based machine with a fanless PSU, fanless CPU heatsink and onboard graphics. There's only one fan in the system - a large 180mm intake fan that blows unimpeded across the CPU heatsink.

PSU - Seasonic Fanless X-460W
Heatsink - Zalman FX-100

I honestly feel the SQ is noticeably better than a Mac Mini (Bootcamp) running the same OS/software. The Mini is also a quad core (albeit Ivy Bridge).

The key aspect I think is to minimise the interference from fans and other moving parts, so I have also used a boot drive 240GB SSD.
You can also go with a liquid cooled system - I only hear mine on boot up.
Things you should be looking into:
8 core CPU.
16 gigs of memory (speed not really important as quantity)
Asus motherboard (A personal preference)
Linear power supply (instead of a standard, switching PSU)
Quality cabling.
Power conditioning (like any other audio component).
A separate power supply for your DAC (if it's USB powered).
Windows Server 2012 R2. Stripping out the OS will noticeably improve SQ (while reducing functionality).

If you're going to use the computer for playback, everyday usage/editing you may want to consider dual booting two OSs
I pretty much agree with Billbartuska. Although that much memory might be too much in my view. If going WS2012, consider the Optimizer. It made a huge difference in my system.

For what it's worth, four months ago I wanted to build a new server and Marcin, maker of JPlay, advised to buy quad core. He said he couldn't explain why, but in his experience quad core sound better than dual, which in turn sound better than single-core. I didn't try the options, but got a Xeon 1265lv2 and been extremely happy with it.
Just make sure you install he 64 bit version of the OS softwear (windows) and the 64 bit version of your audio system. the extra 32 bits make a huge difference. I wish I did it.
I have an intel 6 core with hyper threading on a windows 64 system with no problems. My last system was almost the same but with quad core.
Billbartuska, I'm not sure what you mean by dual booting two OS's. (Windows 7 and Linux, for instance?) With modern machines, nobody really dual-boots anymore. If they truly need the availability of two different operating systems, then they run a hypervisor and open a Virtual Machine for each OS they want to have available. There is a very minor performance penalty to pay compared to a dedicated single-OS machine, but with modern hardware it truly is negligible against the benefits of infinite flexibility.

To answer the OP's question, any of those processors will work well for the task at hand. The E5 series is typically more utilized in servers, so if you build around this processor you might need to get a server-grade motherboard (such as from SuperMicro) to work well with it. These processors might also use ECC RAM; you'll need to check on this. If I recall, the E5 series, unlike the core i5/i7, don't have integrated graphics features, although if you're doing video editing you're going to have your own video card anyway, so it won't factor into your equation.

The core i5 or i7 tends to be used more often in desktop machines. I would personally go with one of these. It's going to be easier to find a compatible motherboard. The difference between the i5 and i7 is that the i7 supports hyper threading, so it can run more threads per core. For a server setup, where you might have hundreds or thousands of different machines making simultaneous requests that each spawn a new thread, this might make a difference. For a desktop machine for video editing, I highly doubt it will make a difference. You will need to look at the software you're planning on using for the editing to see just how well it can handle parallel processing. If you're software is single-threaded, you are unlikely to get any additional advantage to having more processor cores or hyper threading.

Any of these processors with at least 4 cores will be fully up to the task. I agree with the 16GB of RAM. For video editing, you will also need very copious storage space that can be quickly accessed. So at the very minimum, a good 4TB hard drive with a SATA 6Gb/s connection. If you're editing a lot of Blu-ray discs, you will need to investigate RAID to allow you to utilize a large amount of storage (more than what a single hard drive). You'll also need a good backup plan with an external hard drive.

I don't see how the choice of processors here will affect audio quality in the least. It won't make a bit of difference for editing. For playback, as long as the processor can keep up with the audio/video streams without interruption (and realistically any modern hardware can do this with very little CPU load), it shouldn't matter.

And for a video editing system, you'll need big displays and a comfortable keyboard/mouse interface, so it's unlikely to be embedded in your audio rack. Consequently, fan noise shouldn't matter. Now, if the system were to be a home theater PC that was effectively another component in the rack, then you would be considering a low-noise strategy (large fans, maybe active heat sinks or water cooling). But for a video editing system, it's likely to be in your office or wherever, so that's probably not a primary concern.

Put simply, the specific processor choice shouldn't matter tremendously. I feel the more important thing is to have the drive space, video card, software, and RAM to effectively deal with large-file video editing.

Michael
04-18-14: Billbartuska
Things you should be looking into:
... Windows Server 2012 R2. Stripping out the OS will noticeably improve SQ (while reducing functionality). If you're going to use the computer for playback, everyday usage/editing you may want to consider dual booting two OSs

04-20-14: Sufentanil
Billbartuska, I'm not sure what you mean by dual booting two OS's. (Windows 7 and Linux, for instance?) With modern machines, nobody really dual-boots anymore. If they truly need the availability of two different operating systems, then they run a hypervisor and open a Virtual Machine for each OS they want to have available. There is a very minor performance penalty to pay compared to a dedicated single-OS machine, but with modern hardware it truly is negligible against the benefits of infinite flexibility.
Michael, I for one dual boot Windows 7 and Windows XP, booting the XP installation on the infrequent occasions when I find it necessary to utilize older programs or hardware that won't run on 7. (Of course, I do not access the Internet via XP now that security patches for it have been discontinued).

I utilize Terabyte Unlimited's "BootIt Bare Metal" boot manager, which allows multi-booting of 3 or 4 or even more OS's. The OS's are installed into separate partitions on the hard drive, and are kept completely independent of each other, and hidden from each other.

I don't know if Windows 7 and 8 include a built-in dual boot capability (I know that XP did), but even if they do I would recommend to anyone interested that it NOT be used, assuming it functions similarly to the one in XP. The one in XP did not keep the OS's truly independent, resulting in several potential major issues. See the section entitled "What's Wrong With The Microsoft Way" at the middle of this page.

The Terabyte program, btw, includes nice partition management capabilities, and can be purchased as a package with some excellent disk imaging programs, at surprisingly low cost. IMO (and I suspect you would agree) everyone who makes any half-way serious use of a computer should periodically image their system drive (i.e., what is usually the "c" drive in Windows). Although very few people seem to do that, which is why when hard drives fail most people lose a great deal of time even if their data has been backed up.

Best regards,
-- Al
Thanks for the info, Al. There's a lot of look into there. Do you have many programs nowadays that only run on XP?

I still contend that the VM-based system is much more flexible. It's what I do in my closet-based server, so that I can simply spawn up a new Virtual Machine in whatever OS I need to run some latest and greatest software only available on that platform. (Realistically, though, I can run everything I want/need on Linux, but I have the ability to deploy Windows VM's as needed.) And all without reconfiguring hardware, etc.

But back to the OP's question: Video editing and concern for collateral damage to the audio quality with a poor choice in processors. My answer would be: That's not a concern. Just choose an audio encoding format that has good sound quality. It might help if you could list the software you plan on using for your video editing. That will dictate the OS's that it runs on, how multi-core compatible it is, etc. And do you plan on doing a lot of 3D editing and playback, or only 2D? (It makes the difference between suggesting a $300 video card or an $80 video card, unless you do a lot of gaming on the machine as well, in which case you should get the more powerful video card.)

Michael
Michael, thanks for your inputs.

A key question I would have concerning the choice between multi-booting and using a virtual machine, to which I don't know the answer, is whether an existing image of a base (non-VM) OS installation can be restored into a VM, and still run properly.

For example, referring to what I described earlier that I did with some of my own computers, let's say that a computer has been running XP for several years. I create an image of that "c" drive or partition, store the image file on a second hard drive, then I reformat the main drive, deleting that "c" partition, and I install Windows 7. I then set up a VM in Windows 7. If I then restore the XP image to that VM (assuming the imaging program makes that possible), will the restored image work properly, without a lot of sophisticated tweaking?

I don't know the answer to that question, but I'm dubious that the answer is yes. If the answer is no, it would make multi-booting the clear choice vs. a VM in that situation, because using the VM approach would probably require reinstallation of the OS, drivers, programs, data files, settings, options, preferences, updates, etc., none of which is necessary when restoring an image to a multi-booted configuration. Also, I would expect that re-activation issues might arise for some software if it has to be installed into a VM after having previously been installed into a base OS, especially if it has previously been installed a significant number of times.
Do you have many programs nowadays that only run on XP?
Not many, but there are definitely occasions that occur from time to time when my wife and I need to open proprietary file types that were created in the past with programs that are now obsolete and won't run on Windows 7.

Although I understand that at least some versions of 7 have a compatibility mode which emulates earlier versions of Windows. I haven't tried that mode, but I would have my doubts about its effectiveness in all such situations.

Best regards,
-- Al
If you are going to buy a new pc and just use it for audio anyway you might want to consider a dedicated music player like the Bryston BDP-1 or BDP-2. Not sure how much you were going to spend for the pc but just another thought.