OVERSAMPLING IN PLUGINS “MADE BY BX”

在偶然的机会下, 看到Gearspace论坛中有人转载了一段来自于facebook上Brainworx对其插件所使用超采样技术的解释, 我觉得这很有趣, 多少可以令人理解一下不同开发者对于OS的理解和使用方式, 也可以避免用户们对于OS技术有太多不切实际的猜想. 全文如下:

“All analog modeled plugins “made by BX” apply oversampling internally whenever it is necessary, in a really clever way. We are typically not simply oversampling the whole plugin, as this would increase the CPU/DSP load unnecessarily in most cases.

Especially on DSP systems, where a plugin always has to “reserve” the worst case DSP load this wouldn’t be great. The same would be true for plugins like our SSL console emulations, which get used on dozens of channels in many mixes. CPU/DSP efficiency is key here.

The way our system works is that we basically make sure that any crucial part of analog modeled circuits run with a sample rate of at least 176Khz internally.

Our Upsampling Settings, depending on your session settings:
– Below 50kHz (for example 44.1 and 48): 4x
– Below 100kHz (for example 88.2 and 96): 2x
– Above 100kHz (176.4 and 192): 1x

We don’t offer these Upsampling modes to be selectable or switchable by the user, because we believe they are highly optimized for each circuit and application the way we have integrated our Upsampling.
Now if you use external plugins to upsample a complete plugin 8x for example) in a 44.1kHz session that means that you are now effectively using up to 32x (!) oversampling in our plugin (4x internally times).
As you can see in some online videos even at such extreme setting some circuits still show some visible Aliasing at very minor levels (-80dB for example). In real life that is typically nothing to worry about, and it shows that certain circuits would have to be upsampled to unhealthy sample rates for your CPU. After all, you probably need more than one plugin per session…

Upsampling is always a compromise between CPU/DSP usage and reducing Aliasing. And most digital algorithms are compromises, just like most analog gear has theoretical flaws and “mistakes”. Over the decades the human ear has learned to like these “imperfections”, so after all the most crucial question to us is always: can you hear any of the compromises or flaws in a negative way. Not on test tones and in labs, but on real life audio signals, in a realistic environment…?

In general, if you can use higher sample rates in your sessions, please do so. If your computer can handle the track count you need at 96k, this will certainly not give you worse results than recording at 44.1kH. Although we know from many hit producers that they work in 44k/24 Bits or slightly higher, not necessarily in 192kHz. At higher sample rates you make sure that EVERYTHING in an algorithm plays at double-speed, so to speak, not just the parts that have been upsampled on purpose. Those actually continue to use 176.4 or 192kHz, see the chart above.

Brainworx as a company has more than 15 years of experience in modeling analog circuits, and we have a whole team of DSP and analog experts working on our plugins, always in close cooperation with the analog partner companies who make the original units and know them inside out. You can trust that all our plugins are being tested under high standards, and matched with their hardware idols according to state-of-the-art modeling methods in professional real-life scenarios.

As you can see in some videos on YouTube, even Upsampling 32x doesn’t get rid of 100% of all the Aliasing you can imagine or enforce, but that certainly shouldn’t stop you from enjoying our modeled plugins or that of some other cool digital companies. In the end the issue even varies from one analog circuit to another…

The only alternative to using plugin emulations of analog gear is… to use real analog gear. At Brainworx, we are fans and believers in analog, so if that’s what you want to do and what you can do on a daily basis, please go ahead and do it!

All things combined we do believe that high quality analog emulations are superior to the all-analog experience over a whole production cycle, that’s if you take cost, speed and convenience, recall-ability, presets and other things into consideration.

But there is no denying that analog hardware is something to be admired. Even in 2020!”

由于Brainworx是Plugin Alliance插件的主力部队, 可以说PA的大部分插件使用的超采样概念, 基本就如同BX所宣称的方式. 但Brainworx也声明, PA上其他品牌的插件, 则各自使用不同的OS技术.

Brainworx所发表的原文链接如下:

OVERSAMPLING IN PLUGINS “MADE BY BX”… – Brainworx Audio Plugins | Facebook