Blog‎ > ‎

Well, that explains things...

posted Nov 14, 2011, 1:22 PM by Frank Adrian   [ updated Nov 14, 2011, 1:28 PM ]
I've been troubled with my DAW system running slowly. About two months ago, what used to be able to run about 50-60 plugins with no trouble now was having problems with a dozen or so. This caused me to have to do a lot more bouncing/freezing of effected tracks and really killed my workflow. The only good news is that it had also caused me to use fewer plugins. I've been trying to figure out what was going wrong, but had been making no headway. I finally Googled the phrase "optimize settings reaper plugins" today and went to an article that had this useful information: "Besides that, especially resampling due to Reaper setting the driver to a different sample rate etc. could have much more influence on that." Why did this one line from a search result matter so much to me?

I've been using an old Mackie Onyx 400F as my audio interface for the past couple years. I bought it used on eBay and it worked well on Windows XP as a replacement for my old Echo Digital Gina 3G, which in turn, was a good replacement for my Roland (rebranded from Edirol) FA-66. The problem came when I upgraded from Windows XP to Windows 7 earlier this year. Unfortunately, the 400F unit did not have Win7 drivers (nor is it likely to ever have one - Mackie has moved on from that unit... welcome to the digital world of support), but I managed to get it up and running with the Windows Vista driver that Mackie originally provided for the unit. However, but there was one issue...

I normally use a 48K sample rate for my projects. The audio interface was set to that rate and all was good. Well, except that occasionally, the Onyx 400F would jump to a 192K sample rate with no prompting from the operator, causing playback to speed up by a factor of four and causing take failure and embarrassment for the recording engineer. My assumption was that this was an issue with using the Vista driver when used on a Win7 system. Luckily, in the past, most of my recording has been done for myself or my band, so no big deal - just reset the sample rate and run the take again. But lately, I've started recording other people. I didn't want the sample rate slip and the playback speed issue occurring when I was doing "real" work. So I just started keeping the sample rate for the system set at 192K. After all, a finer time resolution is better, isn't it?

I should have known better - first of all, my disc I/O rates and storage sizes when recording went through the roof. When recording at 192K, you're passing along four times as much data as when you're recording at 48K. Besides shifting all of that extra data, you're also processing it when putting it through a plug-in. Four times the samples means using four times the CPU you normally would - which leads us to the "what used to be able to run about 50-60 plugins with no trouble now was having problems with a dozen or so" statement above. So, starting tonight, I'm going to go back to the 48K sample rate and see if that helps - it should. I should have spotted this myself before I had the genius idea of sampling at a higher rate.

The takeaways? Don't sample at a higher rate or greater bit-depth than you need to. Anything higher than 48K at 24-bits is probably overkill and will probably not affect sound quality, certainly when you pass them into the 16-bit, 44.1K world of CD audio. Second, Google is your friend. It's amazing what you can find. I found the answer within thirty seconds of typing the search. Finally, don't procrastinate. I would have saved myself a lot of heartbreak by searching for information when I first saw the issue in the system. In my defense, I needed to perceive the change and diagnose the problem as performance before I was able to do this effectively. Alternately, I knew that this was the issue about three weeks before I actually did the search - I was busy and told myself that getting through the next few weeks "as is" was better than dicking around with the system. Now, knowing what I know, I have to go and make two setting changes. Searching and fixing things would have saved me all of the time I used to bounce tracks, dicking around with settings trying to make the system run faster, etc., etc., etc. Stupid is as stupid does...

The good news? After I'm done recording the demo for my latest song for my band (tonight, with any luck - I have revised vocals for two verses to record, tune, and mix), I plan to pull the Onyx 400F and replace with my new MOTU 24I/O audio interface. I should get more channels, lower latency, and a more stable driver. The downside? I have to re-wire my patch bay (never a fun thing due to tightness of physical access), and grub around with my computer system - an activity that's always fraught with danger. My son will be home later this week, though, and he can help me...
Comments