SNES SPC - What settings do you use when listening? (Sample Rate + Interpolation techniques)

[Pyro Paper Planes]

When listening to SNES-SPC files, what settings do you prefer? If I'm not mistaken, the original SPC700 soundchip on the SNES was (usually) limited to a sample rate of 32000Hz, and utilized a gaussian interpolation technique. However, most SPC players allow you to select higher sample rates and implement different types of interpolation (None, Linear, Cubic, Gaussian). At higher sample rates, is the SPC file simply being upscaled, or is the data actually preserved? Do you prefer trying to emulate the Super Nintendo's limitations, or prefer the higher sample rates and different (if any) interpolation techniques? 

[lazygecko]

I mostly just stick to the original 32khz rate and with filtering enabled.

What higher sample rates bring to the table is entirely dependant on the nature of the samples and how they are used in the respective soundtrack. If it contains sounds that are often played at tones above the native pitches they are stored in, then it might sound a bit brighter. I think soundtracks with lots of simplistic waveform sounds usually benefit the most from this. But a soundtrack like Super Metroid, which mostly uses instruments stored at a high pitch at 32khz and are then downsampled, will not gain anything from that.

Disabling or cutting back on interpolation is very hit and miss. I think it would generally follow the same rule of thumb I described above. Simple sounds might sound a bit sharper and crunchier with less interpolation which can arguably be a benefit. But the technical nature of a soundtrack like Super Metroid is actually just going to harm it and turn the whole thing into an aliased mess.

[Pyro Paper Planes]

The tracks are definitely brighter with Cubic Interpolation vs Gaussian Interpolation. I keep flipping back and forth between the two settings. It reminds me about the debate of whether scan lines contribute to older games; They technically provide an inferior picture, but the pixel art was often designed with the limitation in mind. While the Cubic Interpolation provides a more clarified sound, I have a feeling some of the blemishes were supposed to be hidden.

To go into specifics, I'm using JCOM SPC to isolate the individual channels. I'm trying to get the most authentic sound out of the tracks. So you would suggest 32000Hz with Gaussian Interpolation for something like Super Metroid? 

[lazygecko]

Seeing as composers didn't have a choice in the matter when originally composing for the hardware, it's pretty safe to say that the interpolation is part of the artistic intent.

I think with module-based music from Amiga and PC games the interpolation condundrum becomes more up in the air. Players from that era usually lacked any sort of filtering, but it's a standard feature today. Thus modern recordings of soundtracks (Like official OST releases or YouTube uploads) in those formats often end up with some form of interpolation active, which in many cases filters off the rough edges to a serious degree. I find this kind of aggravating since it often feels apparent to me that the aliasing is an intended part of the sound and not just a byproduct. One of the biggest examples I can think of is Isotoxin from Unreal. Here is a video of it with interpolation enabled:

 

And here is a recording I made from the original module without any interpolation:

https://dl.dropboxusercontent.com/u/66640537/isotoxin.mp3

You can clearly hear just how excessively subdued the main distorted synth line becomes once you start filtering it. The aliasing adds so much brightness to it that it simply feels evident to me that this is how it was meant to sound in the mix, since you can at times barely even hear it in the full mix if all that aliasing is cut off.

[Pyro Paper Planes]

This might sound ignorant of me, but I've never really considered interpolation in a mix until now. While I've noticed the sound difference in the past, I always assumed it boiled down to a quality issue or side effect of the ripped files vs. playing off the soundchip itself.

Thanks for your advice on this lazygecko. I'm pretty sure you've helped me out in the past too.