How much CPU is enough?

[theEmbark]

So I am trying to wrap my head around how much CPU is enough for various audio projects. I'm getting ready to preform a new build for a buddy and don't want to over or under sell the CPU.

So what would be an example of CPUs that would be needed for the following:

-Multi track recording (6 tracks)
-Multi track recording (12 tracks)
-Multi track recording (24+ tracks)

-10-50 track composition (all loaded with VSTs)
-50-100 track composition (all loaded with VSTs)
-100+ track composition (all loaded with VSTs)

-10-50 track composition (VST/live audio mix)
-50-100 track composition (VST/live audio mix)
-100+ track composition (VST/live audio mix)

Some processors I have in mind are the older Xeons like the x5660 and x5680 (and lower). As well as the newer i5 and i7 machines.

Multi core processors seem more important then high clock rate from everything I've seen and read but how many cores are required. Do I need to go dual xeons or even the E5 route for some of these applications or does a run of the mill i7 4 core do the trick these days?

I realize software is kind of the X factor here. Assume Cubase as the DAW of choice in this situation.

Thanks,
Kevin

[Daags]

any idea what vsts ?

[theEmbark]

I'm kind of generally speaking but here's a short list:

Ample sounds (various guitars/basses)
Native Instruments
Serum
TAL
Superior Drummer
XLN Keys
XLN Drummer
IRcam solo instruments
East West: Symphonic Orchestra

Edit: Also probably a lot of stuff from waves but I was thinking more instruments vs. effects at the moment

Those are the main ones.

Thanks,
Kevin

[Daags]

well, Serum can be pretty hungry .... and in terms of NI, anything relating to the reaktor user library can be monstrously hungry, even the newer NI creations devour CPU, i.e Monark and Blocks.

I'm using a 4 core 2ghz cpu, and one instance of either of those can frequently choke my cpu, at max buffer settings... or push it right to the edge leaving little or no room for more plugins on that core.

the rest of the plugs you listed should be fine on a current middle of the road CPU.

I honestly don't think you can oversell on clock speed, when it comes to vsts. obviously when shopping around, once you start reaching that area where the law of diminishing returns applies ... it's hardly worth spending an extra $400 for a .2ghz bump in speed speed. But my personal advice to anyone buying or building a pc for audio would be to buy the fastest clock they can afford. if it's a bit unneccessary today, you can be sure it won't be next year.

ymmv..

[ATN69]

I am on i7 - dual core, 3GHz. It's a Dell Latitude. There are certain plugins that might push me to the limit and that also goes for effect plugins (FX). Most of the listed plugins (the ones I know about) are quite low on the CPU except maybe Serum, but for Serum it depends on the number of voices used, etc. If you are talking about +100 tracks with vst included I would say you need a pretty good CPU. I seldom pass 40 tracks and most of the time I don't have problems with pops and cracks. My average CPU load for such complete track is around 80% to 85% maybe.

It is not only for the vst instrument you need CPU capacity, but once you start adding FX to that it will increase the load. Some FX are easy on the CPU while others can load down the CPU quite much. For me I would say the i7 quad is a minimum because as a user you don't want to buy stuff, install everything with licenses and all, just to discover that the CPU capacity was not enough.

There are ways that will free up CPU load as well. External USB sound card is one example. Optimizing the system is important and it will help to keep CPU load down a bit.

[theEmbark]

well, Serum can be pretty hungry .... and in terms of NI, anything relating to the reaktor user library can be monstrously hungry, even the newer NI creations devour CPU, i.e Monark and Blocks.

I'm using a 4 core 2ghz cpu, and one instance of either of those can frequently choke my cpu, at max buffer settings... or push it right to the edge leaving little or no room for more plugins on that core.

the rest of the plugs you listed should be fine on a current middle of the road CPU.

I honestly don't think you can oversell on clock speed, when it comes to vsts. obviously when shopping around, once you start reaching that area where the law of diminishing returns applies ... it's hardly worth spending an extra $400 for a .2ghz bump in speed speed. But my personal advice to anyone buying or building a pc for audio would be to buy the fastest clock they can afford. if it's a bit unneccessary today, you can be sure it won't be next year.

ymmv..

Thanks for your reply,

And yes, Serum can be pretty intense on CPU. I have a i7 4 core 2.5ghz CPU on this MBP but once I load in a virtual bass, 2 guitars, drums, and a couple synths I've pretty much maxed out. Now my work station is a different story...

I do agree with you on clock speed - however most CPUs come out of the box at a decent rate. At least most that I am looking at.

I guess what I am really looking at is whether to go with a newer system based on something like a i7 4790k which would give me 4 cores at 4.0ghz. For $340.

or

Another Xeon powered machine where I could run a x5680 with 6 cores and a clock speed of 3.33ghz which can easily OC to 4.2-4.5ghz. These run about $150. With the benefit of being able to run dual for around $280.

So the prices are relatively close. I just faced this same dilemma for my own build and went with dual x5680s for my needs. Choosing the older chip does come with the downside of DDR3 RAM but honestly I'm not so impressed with DDR4. It's better but the performance difference doesn't seem to be night and day.

Any advice again appreciated!
Kevin

[theEmbark]

@Daags do you mind describing your average project with your specs? Number of tracks - vsts - etc. Please and thank you!
@ATN69 thank you for your feedback starting a little spreadsheet based on all data collected here

Thanks,
Kevin

[Daags]

There are ways that will free up CPU load as well. External USB sound card is one example.

errmmm. no. not unless you're running DSP on that external soundcard, and using it's on-board fx in lieu of vsts.


@theEmbark

an average project featuring Serum, or Reaktor's hungrier ensembles will be very minimal ... maybe 8 tracks max, and most of them audio that's being bounced/frozen/rendered from the cpu pigs. 2 or 3 sends, with typically no more than 2 or 3 plugs on each ... a limiter on the master, maybe. and I'll often have to scoot around the project turning plugs on and off depending on what's being done, to make it work within my cpu limitations.

[VitaminD]

It is really difficult to say. CPU use can vary wildly from synth to synth and, even in a particular synth, from patch to patch.

Multiply this by 20+ tracks, each having 0-5 insert effects, and it is hard to say with any precise measure.

Then you get into ASIO driver performance, sample and frequency rate, hdd speed etc.. all of these will affect performance.

[Daags]

I guess what I am really looking at is whether to go with a newer system based on something like a i7 4790k which would give me 4 cores at 4.0ghz. For $340.

or

Another Xeon powered machine where I could run a x5680 with 6 cores and a clock speed of 3.33ghz which can easily OC to 4.2-4.5ghz. These run about $150. With the benefit of being able to run dual for around $280.

won't the mobo for a dual xeon setup tip the scales in terms of cost ?
anyway, if it's trivial for you to put together a dual setup with 12 cores running at 3.33 - 4.2ish ghz would be what i'd choose. definitely. no brainer if the alternative is only 4 cores...

[ATN69]

errmmm. no. not unless you're running DSP on that external soundcard, and using it's on-board fx in lieu of vsts.

errmmm. Yes. I can clearly see the difference in CPU load when I run with the onboard sound card and FLStudioASIO compared to Focusrite Scarlet 2i2 and the ASIO drivers from Focusrite.

[theEmbark]

I guess what I am really looking at is whether to go with a newer system based on something like a i7 4790k which would give me 4 cores at 4.0ghz. For $340.

or

Another Xeon powered machine where I could run a x5680 with 6 cores and a clock speed of 3.33ghz which can easily OC to 4.2-4.5ghz. These run about $150. With the benefit of being able to run dual for around $280.

won't the mobo for a dual xeon setup tip the scales in terms of cost ?
anyway, if it's trivial for you to put together a dual setup with 12 cores running at 3.33 - 4.2ish ghz would be what i'd choose. definitely. no brainer if the alternative is only 4 cores...

Valid point about the motherboard. If I can find a SR-2 for $250ish then it works out to be almost the same.

I know if we were talking gaming etc this would be a different story as new GPUs need new boards for the most part but I feel like for audio buffs we just need power. And a BIOS that will run the OS we need for our DAW.

I looked at cubase's specs and there doesn't seem to be a reason that a newer chipset would run better over an older board. The only real difference I personally see is DDR4 which most desktop boards mac at 32 or maybe 64 Gbs. I probably won't even use that but with dual CPUs you can get up for 192gb on certain boards yes it's slower but I bet it benches better .

Anyways I think I solved my dilemma. Just go for another Xeon build and over build.

Thanks for the input,
Kevin

[fluffy_little_something]

100-track composition?!? Ever heard of less is more?
Given the huge differences between plugins, your question is almost impossible to answer. Just take the best Intel CPU you can afford, or maybe wait till October when the new AMD chips will be launched, which is what I will likely do...

[sprnva]

I could be wrong, but in the case of multi-core performance, most (or all) DAWs can only assign a channel to one thread or core. So if you load up a heavy synth/patch and follow it up with some heavy inserts it can choke a slow CPU regardless of how many cores it has. If I was in the market I wouldn't take a CPU slower than 3GHz to cover this and then get one with as many cores as I could afford.

For Xeons you can get older chips quite cheap on ebay as server pulls. The same kind of chips you'd find in the good Mac Pros.

[theEmbark]

I have heard of less is more but its not for me haha

I'm literally finishing a SR-2 build with 2 x5680s as we speak so I'll do some bench mark and latency tests and let my buddy play with mine for a while and see what he's actually using. He's burning thru an older AMD hex core right now however trying to get him to switch/upgrade DAWs too because for whatever reason cakewalk (6 I think he has) burns thru CPU

@sprnva - yup that's what I have right now - 2 x5680s which are 3.33ghz 6 core stock. I've seen them OC to 4.5 at highest not sure how stable that is but getting to 4.0 is a breeze.