Photosounder Spiral development updates

[A_SN]

Almost done.

[Naenyn]

Definitely one of the prettiest plugins out there.

[A_SN]

Definitely one of the prettiest plugins out there.

Thanks! Not surprising given that my share of graphics coding vs sound processing coding for the last 6 years is probably something like 7 to 1 . I've actually learnt very little about sound processing during that time. If anything I should start writing papers for SIGGRAPH.

It looks even better in motion btw, which you'll soon be able to see for yourself as I expect to release it and have a video showcasing it within 2 or 3 weeks. And I might have a release candidate within a few days.

[A_SN]

Alright, I've finally updated the site to the latest build (the last one was over one year old), please try it out and let me know how well it works for you!

All that's lacking from here until the final version is a live rectangular display, not very important. Other than that it's the real deal!

http://photosounder.com/spiral/

[chroma]

I just got this, and i like it, but i found i still like spiral-CM better for some things.
i really love the circular, pitch-based layout, but there are some things in regular analysers i've love to get in that.
maybe i just don't know how all to use it yet? is there a manual for it somewhere? I didn't see one.

but here are some things I'd like:

- ability to control the curve of the analysis. basically, to thin out the amount of detail. this allows e.g. extracting only the loudest frequencies of the signal. maybe easier to implement as just a cutoff of amplitube - frequencies, even if present, below a certain level just aren't shown. or apply some kind of exponential curve so that the amount that the brightness drops per amplitube can be increased. i was using spiral CM sometimes as a guitar tuner (because you can tune not on just the root frequency, but on harmonics too), but regular spiral is just too noisy to do things like that.
- i thought pan gain/width would do this, but didn't do exactly as i expected: spiral CM just shows white for all frequencies, spiral shows different colors for left/right, which is sometimes better, but not always.
- this wouldn't be that useful, but it would look cool (since it doubles as a useful tool and eye candy): some level of persistence would be really fun.
- if this could take a sidechain, and show e.g. differences between the two signals (if you treat the two signals as mono, this would look very much like the pan view), that would be really cool too.

thanks...

[A_SN]

There's no manual except this video which shows pretty much everything that's not hidden https://www.youtube.com/watch?v=cEiKMVB0wmg&vq=hd1080

The answer to your most of your questions is in hidden controls, I had a bunch of knobs that I chose to remove late in the development because I found I never use them anymore, so why clutter the interface with so many knobs. But they're still there, you can access them as sliders from your host's interface.

- ability to control the curve of the analysis. basically, to thin out the amount of detail. this allows e.g. extracting only the loudest frequencies of the signal. maybe easier to implement as just a cutoff of amplitube - frequencies, even if present, below a certain level just aren't shown. or apply some kind of exponential curve so that the amount that the brightness drops per amplitube can be increased. i was using spiral CM sometimes as a guitar tuner (because you can tune not on just the root frequency, but on harmonics too), but regular spiral is just too noisy to do things like that.

The Gamma slider will do that. SpiralCM had a gamma of 1.5 which made things more contrasty, which I initially liked best, but then as time went on I realised it sucks for having a good view of the whole mix (because the rest is too dark) so I progressively prefered to use 1.25, then 1.1, then 1.0, which is the most natural setting given that it gives proportional intensity of light to the sound. Btw if you tune your guitar you should probably want to turn up the resolution to the max, that's what I usually do.

- i thought pan gain/width would do this, but didn't do exactly as i expected: spiral CM just shows white for all frequencies, spiral shows different colors for left/right, which is sometimes better, but not always.

In Spiral colours are limited to a brightness of 80% so that they don't go to white when they're bright. That is so you can still see colours at the brightest, because white has no colour. SpiralCM's colours don't mean much so it's not a problem which is why it goes to white. The good news is there's also a hidden slider that does this, I think it's called Lum. Limit. SpiralCM's visualisation mode is also there, I forgot what it's called but it's there.

- this wouldn't be that useful, but it would look cool (since it doubles as a useful tool and eye candy): some level of persistence would be really fun.

I guess turning up the resolution would do that. I wouldn't implement that.

- if this could take a sidechain, and show e.g. differences between the two signals (if you treat the two signals as mono, this would look very much like the pan view), that would be really cool too.

What do you have in mind? What would the two signals have in common? Like, what type of use are you thinking about?

Btw how is sidechaining done for the user? Does it require two instances of the plugin, with one sending to the other?

[chroma]

The answer to your most of your questions is in hidden controls, I had a bunch of knobs that I chose to remove late in the development because I found I never use them anymore, so why clutter the interface with so many knobs. But they're still there, you can access them as sliders from your host's interface.

ahh, very cool! i did try the ones you mention... did not get exactly what I wanted yet but I will play with them, a quick check shows they do go towards what i'm looking for. the circle (pitch based) concept of spiral is very cool, and makes me think differently, so now i keep wishing it had some of the thing I like from other analysers (mostly i use the melda MMultiAnalyzer, which has a cool sonogram mode that's kind of like spiral, but flat).

what i'd like is something like the 'resolution' control in MMultiAnalyzer (MMA), which is really more like a 'threshold' control. gamma works sort of like that, but not exactly, and doesn't go far enough iirc. but it does go in the right direction, and is useful, so thanks....

(had to be careful playing with the 'hidden' controls... none of the official ones, or the ones you mentioned cause trouble, but the ones called 'col' and 'sat' crashed live when changed...)

in actuality, what i like most about spiral is the wrapped spectrogram, which i think is genius. but... the color spectrum looks pretty, but is not easy to decode information from right away. just two colors, one for left, one for right, and the middle the two mixed, is more traditional, and easier to decode a lot of information from for newbies like me (spiral CM, by being mostly white, does this for mono signals for me).

- this wouldn't be that useful, but it would look cool (since it doubles as a useful tool and eye candy): some level of persistence would be really fun.

I guess turning up the resolution would do that. I wouldn't implement that.

persistence = motion blur. it's a little different from resolution i think, but i'll play with it more. but thinking back, i mostly found it useful for old scope traces; i don't know that it would be that useful for spectrograms.

- if this could take a sidechain, and show e.g. differences between the two signals (if you treat the two signals as mono, this would look very much like the pan view), that would be really cool too.

What do you have in mind? What would the two signals have in common? Like, what type of use are you thinking about?

well, the stereotypical example is sidechaining bass with kick. but there are already lots of tools where you can, e.g. throw a vocal on top of a guitar, and then use an EQ to carve out space for the vocal in the guitar signal where they overlap. but that's kind of coarse sometimes, so you sometimes use dynamic EQs to do this. i use mmultianalyzer for this sometimes (i have even used it live), it shows the spectrograms on top of each others in different colors.

this would give you even more information about the conflict right away... you would know that the guitar has resonances at certain notes, and so avoid playing them, or something like that. i don't really know, i don't use it that much elsewhere, but i know some do, and having it with the notes right there in front of you seems useful....

Btw how is sidechaining done for the user? Does it require two instances of the plugin, with one sending to the other?

i've seen that done.. both DDMF IIEQ and the MMultiAnalyzer support that, and it is easier for the user, but there are plenty of sidechain implementations that just have an extra 2 inputs (so they have 4 inputs instead of 2) and you depend on the host/DAW to handle routing the second signal to the second input. That would work well enough, I would think.

[A_SN]

what i'd like is something like the 'resolution' control in MMultiAnalyzer (MMA), which is really more like a 'threshold' control. gamma works sort of like that, but not exactly, and doesn't go far enough iirc. but it does go in the right direction, and is useful, so thanks....

I see what you mean. But the way they do it is stupid, so I'm not gonna do that. Their intensity scale is logarithmic with a gamma on top. Like... why... So that threshold, which they weirdly named "resolution" (not the only thing they labelled weirdly, their "Super-Resolution" is just variable resolution) just cuts off the lower range abruptly, just... why... So I'm not gonna do that. I think having a totally linear representation of intensity is very clear, even putting a gamma on it is unnecessary, but maybe it takes some time to get used to not seeing a horribly processed visualisation. At least they got one thing right with MMA, the 3 dB/oct slope, it's necessary to correct the intensity of the spectrum when presenting it in a logarithmic frequency scale and therefore showing loudness the correct way, but too few analysers do that so everything looks like a downward slope. In Spiral I found that adjusting the gain can go a long way btw, I think most people I've seen use Spiral turning it way too high, you should usually try to not have too many crushed colours.

(had to be careful playing with the 'hidden' controls... none of the official ones, or the ones you mentioned cause trouble, but the ones called 'col' and 'sat' crashed live when changed...)

Weird, I don't recall having any trouble with them back when they were not hidden, I might have broken something, I should look into it.

in actuality, what i like most about spiral is the wrapped spectrogram, which i think is genius. but... the color spectrum looks pretty, but is not easy to decode information from right away. just two colors, one for left, one for right, and the middle the two mixed, is more traditional, and easier to decode a lot of information from for newbies like me (spiral CM, by being mostly white, does this for mono signals for me).

I tried something like that and I didn't like it as much because it makes it much harder to appreciate the subtleties in pan. It makes everything look either left, centre or right, very hard to appreciate if something is halfway to the right, whereas in Spiral if you see something at 40% right it will be a bluish turquoise kind of green, which is pretty specific and distinct from either yellow or blue. But that's something you can try by tweaking the col and sat knobs (col is the hue on 360 degrees, red is 0°, green is 120°, blue 240° and so on). If the sliders make it crash you can type the values directly into the preferences file, which is in %appdata%.

but thinking back, i mostly found it useful for old scope traces; i don't know that it would be that useful for spectrograms.

Yeah it's more a thing for curves so they don't jump all over the place. Plus remember, Spiral is all about analysing music, you probably don't want the visual equivalent of very strong and long reverb smearing notes all over the place.

i've seen that done.. both DDMF IIEQ and the MMultiAnalyzer support that, and it is easier for the user, but there are plenty of sidechain implementations that just have an extra 2 inputs (so they have 4 inputs instead of 2) and you depend on the host/DAW to handle routing the second signal to the second input. That would work well enough, I would think.

OK, good to know thanks

[chroma]

what i'd like is something like the 'resolution' control in MMultiAnalyzer (MMA), which is really more like a 'threshold' control. gamma works sort of like that, but not exactly, and doesn't go far enough iirc. but it does go in the right direction, and is useful, so thanks....

I see what you mean. But the way they do it is stupid, so I'm not gonna do that. Their intensity scale is logarithmic with a gamma on top. Like... why... So that threshold, which they weirdly named "resolution" (not the only thing they labelled weirdly, their "Super-Resolution" is just variable resolution) just cuts off the lower range abruptly, just... why... So I'm not gonna do that. ... In Spiral I found that adjusting the gain can go a long way btw, I think most people I've seen use Spiral turning it way too high, you should usually try to not have too many crushed colours.

well, i don't know about the first section (i'm not a graphics guy at all but for the second, actually, that's _exactly_ what i want. it's basically noise reduction. if I'm tuning a guitar, for instance, at the low A (110 Hz), there are almost 500 harmonics between the fundamental and nyquist, but i only really care about the first few, which are usually the strongest. if I play a chord, there are many, many more harmonics in there, but i really want to see the 3-10 that are part of my chord. If I want to know the notes, I want to thin this out as much as possible (it's impossible to get just to fundamentals of course), but if you're doing EQ for instance you want the whole picture. sometimes i want something in between...

i'll try playing with the gain some more. i have tried that before, but it's not exactly right either... turn it down and i mostly just see the few dominant frequencies, but in muted colors; turn it up, and the fundamentals get brighter, but also much more noise. am looking for something in the middle.

in actuality, what i like most about spiral is the wrapped spectrogram, which i think is genius. but... the color spectrum looks pretty, but is not easy to decode information from right away. just two colors, one for left, one for right, and the middle the two mixed, is more traditional, and easier to decode a lot of information from for newbies like me (spiral CM, by being mostly white, does this for mono signals for me).

I tried something like that and I didn't like it as much because it makes it much harder to appreciate the subtleties in pan. It makes everything look either left, centre or right, very hard to appreciate if something is halfway to the right, whereas in Spiral if you see something at 40% right it will be a bluish turquoise kind of green, which is pretty specific and distinct from either yellow or blue. But that's something you can try by tweaking the col and sat knobs (col is the hue on 360 degrees, red is 0°, green is 120°, blue 240° and so on). If the sliders make it crash you can type the values directly into the preferences file, which is in %appdata%.

very cool, thanks for info! I will play with this... yeah, it's true that it's mostly 'red' to the left (magenta/red/orange), and 'blue' to the right (blue/green). i forget sometimes if magenta is reddish or blueish, but that shouldn't take too long to remember.

of course, most people can't hear that fine detail in panning anyways... there are some people that work exclusively in L/C/R. but actually your scheme works well for this... if i can't remember every exact color, i can remember that green is ~25% to the right, while blue is all the way there. just had to get used to it, i guess. it's also cool that you might be able to, for instance, pan one sound to 25% left, and another to 30% left; most users wouldn't hear the difference, but they'll show up as a different color in the mix. will have to play with this.

but thinking back, i mostly found it useful for old scope traces; i don't know that it would be that useful for spectrograms.

Yeah it's more a thing for curves so they don't jump all over the place. Plus remember, Spiral is all about analysing music, you probably don't want the visual equivalent of very strong and long reverb smearing notes all over the place.

well, not for analysing... but it might look cool but also, actually, it might make hot spots/resonances easier to see... as the user plays a melody, the active harmonics should move, but resonances won't.

[A_SN]

well, i don't know about the first section (i'm not a graphics guy at all but for the second, actually, that's _exactly_ what i want. it's basically noise reduction. if I'm tuning a guitar, for instance, at the low A (110 Hz), there are almost 500 harmonics between the fundamental and nyquist, but i only really care about the first few, which are usually the strongest. if I play a chord, there are many, many more harmonics in there, but i really want to see the 3-10 that are part of my chord. If I want to know the notes, I want to thin this out as much as possible (it's impossible to get just to fundamentals of course), but if you're doing EQ for instance you want the whole picture. sometimes i want something in between...

Well typically harmonics go down in intensity as they go up, plus they don't overlap at all with the lower ones which is what you care about. You tune with a clean tone, right? Also do you turn up the resolution? See the example late in the Spiral video, that's what tuning an electric guitar should look like. Anyway if a gamma of 2.0 doesn't even solve your problem I'm really gonna need to see a screenshot. And actually for tuning harmonics can be quite useful since they can be more precisely pinpointing in pitch.

of course, most people can't hear that fine detail in panning anyways... there are some people that work exclusively in L/C/R. but actually your scheme works well for this... if i can't remember every exact color, i can remember that green is ~25% to the right, while blue is all the way there. just had to get used to it, i guess. it's also cool that you might be able to, for instance, pan one sound to 25% left, and another to 30% left; most users wouldn't hear the difference, but they'll show up as a different color in the mix. will have to play with this.

Yeah it's not so much about how precisely you can hear anyway, it's about making it easier to tell different instruments apart. If an instrument is green and another is cyan it will be much easier to tell them apart than if one is only a slightly bluer shade of violet than the other. And if you can't remember what colour means what just look at the rainbow thingie below the main visualisation

it might make hot spots/resonances easier to see... as the user plays a melody, the active harmonics should move, but resonances won't.

I have no idea what this means. What do you mean by resonances?

[chroma]

Well typically harmonics go down in intensity as they go up, plus they don't overlap at all with the lower ones which is what you care about. You tune with a clean tone, right? Also do you turn up the resolution? ... And actually for tuning harmonics can be quite useful since they can be more precisely pinpointing in pitch.

maybe that's it... one thing I like about Spiral is that because of how it works, I can just stick a spiral on the master while i'm working and use it from several places, after the whole chain, and it still pretty much works - I can tune on the output of the amp + reverb. but you're right, just moving it would clean it up a lot, using it at the channel is how i (have to) use other tuners today anyways.

made me think about something else though... maybe it's earlier in the thread: i was wondering if some of what i'm seeing is the difference between just vs. pure intonation etc. which made me wonder, does spiral take .tun files or support starting at other than 440Hz?

+1 for the harmonics - i note that the upper harmonics don't always seem aligned like the fundamental. not sure how that happens. also, the higher harmonics also seem to be a little off too done that way. but this lets me kind of shoot the middle between fundamental exactly on pitch, and all the harmonics showing on pitch, which sometimes sounds better.

Yeah it's not so much about how precisely you can hear anyway, it's about making it easier to tell different instruments apart. If an instrument is green and another is cyan it will be much easier to tell them apart than if one is only a slightly bluer shade of violet than the other. And if you can't remember what colour means what just look at the rainbow thingie below the main visualisation

well, i guess my point was sometimes you want this, and sometimes you just want an overall picture of where you're leaning L/R, in which case the simpler color scheme carries more immediate information. or maybe not... i just started with this, and some of this is just questions based on how i can imagine myself using it (haven't had much time since i got it yet to try everything).

it might make hot spots/resonances easier to see... as the user plays a melody, the active harmonics should move, but resonances won't.

I have no idea what this means. What do you mean by resonances?

room resonances etc. i'm not sure if this would actually work, but e.g. this means that as a singer moved around in pitch, the frequency of the room resonance would be excited at different pitches, while melody-related harmonics would only be seen when the singer was actually singing that note. so if you play with persistence, you might get the note harmonics to fade away, while the resonances persist. i don't know if it would work or not.

[chroma]

Wow, I realized last night that it was still in SpiralCM display mode - which works really well for some things (and for mono signals, having the colors change per octave can be occasionally useful) but switching back to the intended mode made the colors make a lot more sense. Also putting it on the clean guitar signal and playing with gamma/color gain worked a lot better. so thanks!