The Foxboro Plug-In Upsampling Thread

I'm pretty sure there are going to be questions/comments about this, so thought I'd be pre-emptive and create a thread so related posts wouldn't get lost in a more general Foxboro thread.
 
First thing I'd recommend is reading the eZine description of what it does, and the limitations. It's a very new concept so there are some fine points.

FYI
Web page (http://static.cakewalk.co...nar_foxboro_update.pdf/) reports as not available @ 12:28 EDT

Why would there be a problem with the way its always been? Where is the oversampling meaningful, in what pert of the spectrum? I am a bit doubtful as to its necessity. 
  

John
Why would there be a problem with the way its always been? Where is the oversampling meaningful, in what pert of the spectrum? I am a bit doubtful as to its necessity. 
  

I love that feature of Metaplugin(2xoversampling), and always run Dimension strings programs inside that.
Quite noticable difference.
 
I guess it depends on quality of sample libraries also.
One that stretch samples a lot to resample to many pitches is especially great value.
One of quality sampled at every pitch in keyboard range, less so.
 
In general you could say that aliasing is reduced. Some rough edges of mid and high frequency content reduced.
 
Maybe start with some chords of strings.

John
Why would there be a problem with the way its always been? Where is the oversampling meaningful, in what pert of the spectrum? I am a bit doubtful as to its necessity. 
 

 
Excerpted from the eZine:
 
Some plug-ins, both processors and virtual instruments, can produce unwanted artifacts when running at lower sample rates (e.g., 44.1 and 48 kHz) if they don’t oversample internally and lots of high frequencies are present. Most modern plug-ins give the option to oversample at the expense of drawing more CPU power, but many older ones still in common use do not. Amp sims and synths are affected the most, but so are dynamics processors and some reverbs. The artifacts result from “foldover distortion,” which produces a sort of “wooly” noise when higher frequencies from the digital signal processing "fold back" to create noise in the audio range.
 
The typical workaround is running projects at higher sample rates, such as 88.2 or 96 kHz. However this uses more CPU power, which can limit the number of tracks and plug-ins you can run in real time.
 
[Upsampling] provides the benefits of processing or generating audio at a higher sample rate in projects using lower sample rates (e.g., 44.1 or 48 kHz). When selected, SONAR begins the bounce process by upsampling the incoming audio to the specified higher sample rate, processes the plug-in at the new rate, then downsamples the resulting output to the current project sample rate. This process happens automatically, behind the scenes; it works with VST, DX and/or virtual instruments.
 
LIMITATIONS OF UPSAMPLING
 
Please note that only some plug-ins, generally older ones, benefit from upsampling and only if significant high frequencies are present.If no harmonics exist that reach into the range of the clock, there will be no foldover distortion, hence no need for upsampling.
 
There can be a significant improvement in sound quality with some plug-ins, no improvement with others, and a few may actually sound worse. So, upsampling is enabled on a per-plug-in basis—in other words, enabling upsampling for one plug-in enables it for all instances of that one plug-in, in any project. Because this rendering process is CPU-intensive, do not enable upsampling for a particular plug-in unless you can hear an actual difference.
 
Note that SONAR’s high-end sample rate conversion requires considerable CPU power, so this process is available only when doing a fast (non-real-time) bounce. Also, the maximum upsample rate is 384 kHz, so upsampling is not available for projects that run above 192 kHz; and at present upsampling cannot be applied to plug-ins in surround buses, or to bit-bridged plug-ins or region effects. Finally, note that some plug-ins may not support operating at a higher sample rate. In this case, SONAR displays an error message toast notification, and performs the plug-in bounce at the original project sample rate.
 
It’s also important to remember that the sound designer probably built a sound based on what was heard. If you now process at high sample rates, the sound may be brighter because the high frequencies are no longer being folded back, and there could be less perceived low end because the foldover distortion is no longer there. Whether that sounds “better” or not is subjective.
 
WHY UPSAMPLING CAN IMPROVE AUDIO QUALITY
 
It may seem counter-intuitive that after upsampling to a higher sample rate and rendering, returning to a lower sample rate preserves the benefits of working at the higher sample rate. However, these benefits occur in the audio range, and as low a sample rate as 44.1 kHz has no problem reproducing sound in the audio range. Because upsampling processes at higher frequencies, when sample rate-converted back to a lower sample rate, the frequencies that could cause foldover distortion are no longer present. 
 
 

I just noticed - helpfile says there is to be a field in plugin manager for this render-options - but it's not in my install anyway.
 
But I tested, it does stick as a global setting once set from plugin gui.
 
so no cow on the ice....
 
The old saying "all daws sound as good" is not true anymore...Sonar sound better...

drewfx1
 
It's desirable or necessary for plugins that do processing that creates frequencies greater than 1/2 the sample rate but do not upsample internally for whatever reason (even though they should).
 
For instance any plugin that creates distortion, saturation, etc. as well as some synths that create funky waveforms with loads of high frequency content. As I believe was discussed in the other thread, this might also include things like aggressive limiting.
 
Basically for plugins that don't do it themselves, the high frequencies get filtered out instead of folding over (aliasing/imaging) into the audible range.

Next time I'm having you write the eZine copy 

It's been mentioned that the feature works best on material with a fair bit of HF detail.
 
So..... what if I'm using the same synth for 2 different uses - one for bass & one for percussion? Think Dim Pro etc.

mudgel

Will having the setting checked have a detrimental effect in other hosts? Maybe create an instability or something? Obviously not planned but was it tested?

It is a setting in SONAR not in the plug-in. Plug-ins will run as they always have in other hosts.

You may want to, at least at first because it may affect the mix (or not).

Yes.

scook

mudgel

Will having the setting checked have a detrimental effect in other hosts? Maybe create an instability or something? Obviously not planned but was it tested?

It is a setting in SONAR not in the plug-in. Plug-ins will run as they always have in other hosts.

Please look at the screen capture at the bottom of page five of the eZine. It shows the menu item on the left side of what looks like TH2s interface. Then at the bottom of page 6 it clearly says that it is turned on in each plugin.

mudgel

Please look at the screen capture at the bottom of page five of the eZine. It shows the menu item on the left side of what looks like TH2s interface. Then at the bottom of page 6 it clearly says that it is turned on in each plugin.

It is an option added to the Windows menu by SONAR maintained in SONAR.

scook

mudgel

Please look at the screen capture at the bottom of page five of the eZine. It shows the menu item on the left side of what looks like TH2s interface. Then at the bottom of page 6 it clearly says that it is turned on in each plugin.

It is an option added to the Windows menu by SONAR maintained in SONAR.

Perhaps were splitting hairs but you have to open a plugin not Sonar to get access to the new menu item. If I was strictly following what you said I'd be searching for some preference within Sonar.