guidance with hardware upgrade for Reaper and plug-ins

[yhlee]

Hello! My husband is trying to figure out whether I need an upgraded computer for what I want to do with Reaper, and the trouble is that I am terrible with computers so I don't know what the bottleneck is, and my husband knows computers but has no clue about music. Please forgive me if I get the terminology wrong; I am a hobbyist.

I'm currently running Reaper 5.62 x64 on Windows 7 Professional 64-bit. My processor is an Intel Core i5-2500 CPU @ 3.30 GHz 3.30 GHz (it's listed twice in properties, I don't know why). 32 GB RAM in four 8-GB pieces that are DDR3 1600 SDRAM.

Hard drives: two Western Digital Black 1-TB, 7200 rpm, SATA 6, Gbyte/second, 64 MB cache.

What I'm trying to do: I want to use MIDI with sampled instruments to do basic orchestral arrangements/compositions. What I've been running up against is severe stuttering/lag in Reaper, and I *think* it's because I'm running out of RAM with the number of sampled instruments I'm trying to load, but I'm not actually sure that *is* the problem. And maybe what I'm trying to do is not possible with a single computer, in which case I'd rather know that before spending $$$$$ on very expensive RAM only to have it not work anyway?

The piece that I was having trouble with was using: Orchestral Tools Berlin Strings, Orchestral Tools Metropolis Ark 1, some Vienna Symphonic Library Special Edition (I've done smaller arrangements with just VSL and never had any stuttering problems with it), Drums of War, and some instruments out of Komplete 7. This includes: flute, oboe, clarinet, violin I (long & short articulations), violin II (long & short), viola (long & short), cello (long & short), bass (long & short), various patches from Drums of War, Soundiron High School Drum Corps. The first part of the piece would play up to a point then start stuttering so badly and lag the system so badly it was unworkable. I tried swapping out all the strings from Orchestral Tools Berlin Strings to Heavyocity Novo (on the grounds that maybe only having a single patch per section as opposed to two would improve the situation) but still ran into similar problems.

Is my arrangement too big for a single computer? Given the price of RAM at present I am very hesitant to spend more on it unless I know it's going to actually fix the problem; for all I know the issue is some other piece of hardware (or even software/plug-in??). Any guidance or suggestions would be welcome.

[cfillion]

Originally Posted by yhlee

I *think* it's because I'm running out of RAM with the number of sampled instruments I'm trying to load, but I'm not actually sure that *is* the problem.

You can check if the memory usage is close to 32 GB in the Windows task manager. (If that's the case you can try purging unused samples in Kontakt.)

Audio glitches are usually caused by the audio hardware not receiving a full audio buffer in time. What sample rate and block size are you running at? Does it sound worse when the MIDI Editor is opened?

Check the RT (real-time) values in the Performance Meter window (and possibly per-track CPU usage).



RT CPU = CPU usage of the real-time thread (responsible for audio processing)
RT longest-block = slowest time it took to fill an audio buffer / maximum time until the audio hardware sends it to the monitors
RT xruns = how many incomplete buffers occurred since startup (new since REAPER 5.79)

[yhlee]

Hey, @cfillion, thank you so much--I didn't realize you could display those additional statistics in the Performance Meter. You nailed it--the CPU is going over 100% exactly when the stuttering happens, so it's the CPU, *not* the RAM.

RT longest block starts at 16.9 ms/1.45 ms then goes down to 4.something ms/1.45 ms when things get bad in playback. It reported RT xruns: 0 and Media xruns: 0.

So this probably means I need a faster core? (My husband's words.) In all fairness, this computer is like six years old even though we added RAM to it. It wouldn't be surprising if it needed upgrading...Would you say CPU is the appropriate thing to upgrade--do you have specific recommendations?

[cfillion]

1.45 ms is very short! (64 samples per block at 44.1kHz?) Try increasing the block size (Preferences > Audio > Device). 512 or 1024 should be good. This will give your computer more time (latency) to generate audio and thus lower the RT CPU usage.

[ivansc]

Nobody has asked what is being used as an Audio/MIDI interface yet.

But FWIW even on a quad core i5 just the Vienna library is gonna make it sweat as the tracks build up.

[yhlee]

Hello, @ivansc, my MIDI interface is an M-Audio Uno, although I've been trying to fix playback without even having my keyboard turned on (it's a Komplete Kontrol S88). Right now I'm attempting to get non-stuttering playback of MIDI data that's already been recorded and quantized into a project. I was afraid that all the orchestral tracks were going to be an issue, though.

@cfillion I tried changing the block size to 512 and then 1024. It definitely helps--the RT CPU drops to 33% or 45% depending on the setting. However, playback is now audibly desynchronized, especially in sections where more instruments are playing (easiest to hear with either the percussion in general, or that one tutti section), and in a couple places I'm hearing audio dropouts of sections, so I think it's still struggling a bit.

Thank you both for your help! This is not ideal but is a massive improvement, and these are troubleshooting tips I wouldn't have thought of. (I am embarrassingly bad at computers...)

[cfillion]

Originally Posted by yhlee

However, playback is now audibly desynchronized, especially in sections where more instruments are playing (easiest to hear with either the percussion in general, or that one tutti section), and in a couple places I'm hearing audio dropouts of sections, so I think it's still struggling a bit.

What does disk activity looks like when that happens (in Kontakt and Windows task manager for the other VSTi)?

[yhlee]

Originally Posted by cfillion

What does disk activity looks like when that happens (in Kontakt and Windows task manager for the other VSTi)?

Hello!

So here's the thing--I wasn't getting sound (this happens periodically, especially if I have had the temerity to be listening to iTunes or sound from videos on Chrome or whatever) so I restarted.

I didn't load anything else--no browser, no Photoshop, nothing--just clean restart, then I launched Reaper.

EDIT: to be clear, I closed Photoshop before launching Reaper in the past attempts, because I figured it wouldn't be a good idea to try to run it and Reaper at the same time, but I wonder if it lingered on somehow? I'm sort of foggy about how this stuff works with computers.

Not only did my sound come back (it generally does after a restart), the lag/desynchronization was gone!

I opened the strings in Kontakt and saw CPU usage of around 20% at the highest; Reaper itself reported RT CPU at around 40%.

It seems that the price for this is that when I want to use Reaper I have to restart, but that's better than, e.g., despairingly throwing thousands of dollars into more RAM that wouldn't even fix the problem. So thank you so much for the help troubleshooting and saving me a significant amount of money.

[ivansc]

Cheques and postal orders graciously received...

Glad you got it sorted out!