Eventide blackhole vs VVV

[valhallasound]

Thanks for the pic! Yeah I heard the Blackhole has 30+ allpasses, add to that filtering and feedback + modulation support(linear interpolation?), that is definitely brute force! I do take my hat off for whoever tuned it though, seems they hit the sweet spot.

The linear interpolation makes a big change to the sound. It can make things "duller," to the point where many people prefer the sound of the BlackHole running on the H8000 at 96 kHz. This would push the linear interpolation artifacts into a much higher frequency range, and would make the sound brighter, without being too bright.

Personally, I prefer using linear interpolation for these types of algorithms. It gives a natural, subtle filtering to the decay of the algorithm. The brightness is largely restored when using higher value allpass coefficients, as the high frequencies are in the feedforward signal for each allpass. I like the sound of the Blackhole plugin running at 44.1/48 kHz. I *think* that the Eventide Space is running at 48 kHz, which means that the Blackhole in that pedal will have the lowpass filtering - and it sounds freaking fantastic in that context.

In the Valhalla plugins, when there is a "bright/dark" option, this often controls whether the delay interpolation is linear, versus a brighter type of delay interpolation. VintageVerb combines linear interpolation (for the 70s/80s modes) with downsampling for the 70s mode. This makes a BIG difference, as the artifacts caused by linear interpolation are very dependent on the sampling rate, and running at a 22.05/24 kHz sampling rate internally will put the linear interpolation artifacts into a very audible range.

Sean Costello

[Novalis]

This makes a BIG difference, as the artifacts caused by linear interpolation are very dependent on the sampling rate, and running at a 22.05/24 kHz sampling rate internally will put the linear interpolation artifacts into a very audible range.

Hello Sean,

could you maybe post an audio example in which these interpolation artifacts are very pronounced and clearly audible, please?

This would help my ear to pick up the sound and identify it later... and so that I know what the heck you're all talking about here

[valhallasound]

This makes a BIG difference, as the artifacts caused by linear interpolation are very dependent on the sampling rate, and running at a 22.05/24 kHz sampling rate internally will put the linear interpolation artifacts into a very audible range.

Hello Sean,

could you maybe post an audio example in which these interpolation artifacts are very pronounced and clearly audible, please?

This would help my ear to pick up the sound and identify it later... and so that I know what the heck you're all talking about here

I'm not in front of a DAW right now, but you can hear the differences by using the demo versions of a few Valhalla plugins:

- ValhallaShimmer: The color mode toggles between bright (full-bandwidth delay interpolation) and dark (linear interpolation).
- VintageVerb: Most of the algorithms use linear interpolation in the 80s mode, and full-bandwidth interpolation in the NOW mode.
- ValhallaÜberMod: the EQ Mode switches between bright interpolation and dark interpolation.

[ghettosynth]

So slightly off topic, but related. In an earlier conversation about Blackhole, which I think is linked in this thread somewhere. We were talking about Spacemaster 2 in Reaktor. It was mentioned that it only has some 12 All Pass networks and that Blackhole has some 24. Interestingly, when I first discovered Spacemaster there were two versions and without thinking much about it I assumed that they were the same and that the second version was just newer.

As it turns out, they're not. The original Spacemaster actually has the option to double the length of the early as well as the late networks. You can choose it separately for both the early and the late. So each then has 12 networks per side .Additionally, there is more flexibility in the modulators. I added a pitch shifter to the feedback network so I could get my own DIY shimmer effect, woot!

Anyway, I still like Blackhole, but, Spacemaster is getting more love lately, especially the older one.

[ghettosynth]

Also, while we're a bit off topic, but still close to the topic, Cloudseed has become very stable and sounds awesome. It has a user selectable number of stages for both early and late stages. It's open source if you want to modify it. It's free if you don't. Just download and drop in youg plugins directory. Not my project, I just think that it's cool.

https://github.com/ValdemarOrn/CloudSeed

[Novalis]

This makes a BIG difference, as the artifacts caused by linear interpolation are very dependent on the sampling rate, and running at a 22.05/24 kHz sampling rate internally will put the linear interpolation artifacts into a very audible range.

Hello Sean,

could you maybe post an audio example in which these interpolation artifacts are very pronounced and clearly audible, please?

This would help my ear to pick up the sound and identify it later... and so that I know what the heck you're all talking about here

I'm not in front of a DAW right now, but you can hear the differences by using the demo versions of a few Valhalla plugins:

- ValhallaShimmer: The color mode toggles between bright (full-bandwidth delay interpolation) and dark (linear interpolation).
- VintageVerb: Most of the algorithms use linear interpolation in the 80s mode, and full-bandwidth interpolation in the NOW mode.
- ValhallaÜberMod: the EQ Mode switches between bright interpolation and dark interpolation.

I have VVV, but I would like to know how I can identify what linear interpolation artefacts sounds like.
If somebody could point it out to me once what it is I have to listen for, than I can do it on my own in the future.

[valhallasound]

I have VVV, but I would like to know how I can identify what linear interpolation artefacts sounds like.
If somebody could point it out to me once what it is I have to listen for, than I can do it on my own in the future.

The main artifact: Linear interpolation sounds darker. It doesn't necessarily introduce noise - linear interpolation can be very clean in that regard. The sonic difference tends to be a gentle rolloff of high frequencies, starting at around 1/4 of the sampling rate.

ValhallaShimmer is a really easy place to hear this. The dark color mode just switches over to linear interpolation. That's the only change.

In other plugins, you can listen for the following artifact: If the sound is fairly bright with the modulation depth at zero, but then gets darker as soon as the modulation depth is set to a non-zero value, the plugin is probably using linear interpolation. I remember hearing this artifact in Eventide UltraVerb - it was fairly bright sounding with no modulation, and then instantly got warmer and darker when the modulation depth was turned up. This is due to these plugins setting the delays to an integer value when the mod depth is at zero.

[deastman]

Okay, but which is better: VVV or VVVV? VVVV has one more V, but it doesn't have a vintage hall algorithm.

[ghettosynth]

Okay, but which is better: VVV or VVVV? VVVV has one more V, but it doesn't have a vintage hall algorithm.

The extra V is for vivacious. If that's something that you want in your reverb, you know what to do!

[Funkybot's Evil Twin]

Okay, but which is better: VVV or VVVV? VVVV has one more V, but it doesn't have a vintage hall algorithm.

Wait for Valhalla Vintage Verb version 5 (or VVV vV if you will).

[deastman]

Okay, but which is better: VVV or VVVV? VVVV has one more V, but it doesn't have a vintage hall algorithm.

My joke may have been too obscure for some of this audience...

https://vvvv.org/

[Hermetech Mastering]

I'll take your four and up you one: https://en.wikipedia.org/wiki/Vi_veri_u ... vivus_vici

[ghettosynth]

Okay, but which is better: VVV or VVVV? VVVV has one more V, but it doesn't have a vintage hall algorithm.

My joke may have been too obscure for some of this audience...

https://vvvv.org/

No, it just needed more funny

[Novalis]

The main artifact: Linear interpolation sounds darker. It doesn't necessarily introduce noise - linear interpolation can be very clean in that regard. The sonic difference tends to be a gentle rolloff of high frequencies, starting at around 1/4 of the sampling rate.

Thank you, Sean.

Seems quite a stretch to me to call a gentle rolloff of high frequencies an artefact, though
But I guess this is a question of definition

[valhallasound]

The main artifact: Linear interpolation sounds darker. It doesn't necessarily introduce noise - linear interpolation can be very clean in that regard. The sonic difference tends to be a gentle rolloff of high frequencies, starting at around 1/4 of the sampling rate.

Thank you, Sean.

Seems quite a stretch to me to call a gentle rolloff of high frequencies an artefact, though

Put 24 linearly interpolated delays in series, and then get back to me on that.

If you are listening to a single delay line in isolation, the high frequency loss of linear interpolation is really subtle. In a feedback loop, it becomes more obvious. Blackhole & ValhallaShimmer both use a ton of allpass delays in series, where each allpass uses a linear interpolated delay in its feedback loop. The slight amount of high frequency loss of the delay gets magnified by the feedback loop, and each allpass delay in series will result in additional high frequency loss.

The best way of hearing this is in ValhallaShimmer, in the mono mode. Turn the High Cut up to 15000 Hz, then switch between bright and dark color modes. The Bright mode will have high frequency reverb that lasts as long as the low frequency reverb. The Dark mode will have a much quicker attenuation of high frequencies in the decay.

I call the linear interpolation effects an "artifact," in that the high frequency attenuation is often viewed as an undesirable effect of linear interpolation. In reality, most algorithm developers that use linear interpolation will design the algorithms around these characteristics. Linear interpolated delay lines inside of allpass delays can help tame the high frequency decay of these blocks, which can otherwise sound brittle. In an FDN, you almost always want some high frequency attenuation, as real world acoustic spaces have a fair amount of attenuation at higher frequencies due to air absorption.

Sean Costello