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Comment by throw_m239339 | Hacker News Reader

> The biggest problem with the VCO design is that the control voltage that determines the frequency is generated by a complex circuit that is very sensitive to temperature drift and manufacturing tolerances. This means that the generated control voltage might not match up to exactly to what it should be for the desired note and it'll end up sounding out of tune. What's worse is that even if you adjust for this you'll need to re-adjust as the instrument gets warmer!

Instability ironically prized and cherished by synth enthusiasts who will claim it makes old synthesizers sound "better" than modern ones...

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Scientifically perfect output has rarely been a primary desideratum of musical instrumentation and in fact is somewhat limiting in terms of the number of timbres you can create. Ergo why historic analog synths included multiple oscillators per-voice with independent tuning. The early Junos famously included a chorus to thicken up its single DCO per-voice. Later digital Roland synths introduced the "super saw" which is many superimposed detuned oscillators. Going back further, a full orchestra or choir ensemble is certainly not exactly in tune across every performer.

And as someone who makes digital synths for a living even 100% accurate fully digital oscillators are difficult to fully realize in practice. Aliasing concerns abound at every stage of a softsynth- there are well-known formulas for calculating alias-free waveforms at a fixed frequency, but these start to get expensive when you also are considering PWM and frequency modulation which are essential tools for achieving a variety of different sounds. And aliasing sounds a lot worse than analog imperfections.

A lot of the best commercial softsynths now support all kinds of audio-rate modulations everywhere in the signal chain. I guess they must just be throwing CPU power at it and oversampling the crap out of everything.

Basically - yes. There's now enough CPU to do this.

But there's more to that analog sound. The opamps and the rest of the circuitry, including supposedly passive elements like resistors and capacitors, all add tiny amounts of distortion and other parasitic interaction with the rest of the synth which varies with frequency content, level, and dynamics.

Human ears are incredibly sensitive to these variations, and the circuits in 70s and 80s synths had a lot of components, all adding their own colour. Which is why if you A/B the hardware with the software, the software rarely wins.

In DSP terms there are differences between functional/abstract models, component-level models, and component-level models that include these complications and imperfections. There hasn't been a lot of work done on the latter, and if they were modelled accurately they would likely need an order of magnitude more DSP cycles than current VSTs.

This is true although I find that the current emulations are good enough for a lot of sounds, especially when they’re buried in a mix and played back on a low bit rate stream on bad speakers.

>aliasing sounds a lot worse than analog imperfections

The Commodore Amiga has the crudest possible anti-aliasing filter: a single fixed-frequency low-pass filter shared by all 4 channels. It does not work very well, so aliasing is a defining characteristic of the Amiga sound. Aliasing adds high frequency content that compensates for the low sample rates required by memory limitations, and extra harmonic complexity that compensates for the low channel count. I think Amiga modules sound worse if played by something with good anti-aliasing filters.

Brian Eno’s quote comes to mind:

> Whatever you now find weird, ugly, uncomfortable and nasty about a new medium will surely become its signature. CD distortion, the jitteriness of digital video, the crap sound of 8-bit - all of these will be cherished and emulated as soon as they can be avoided.

In my (pedantic) understanding, the Amiga doesn't suffer from aliasing, because it uses a period register used to divide a very high frequency (rather than a frequency register), and always spends an integer number of clocks (output samples) on each input sample. However, it suffers from imaging (a reconstruction artifact) due to using a stair-step (zero-order hold) as a reconstruction filter. And IMO reconstruction artifacts sound worse (not harmonically spaced) when the sampling rate isn't an integer multiple of the note's frequency (the note pitch's period isn't an integer number of samples).

Aliasing (a sampling artifact) is an issue in synthesizers which run at low/fixed sampling rates and sample waveforms to produce output (often using frequency registers). This includes modern software synthesis, and also hardware like DS (ZOH, samples, almost like Amiga), N163 (ZOH, short wavetables), Yamaha (FM on sine waves, IDK the details), and to a lesser extent SNES (Gaussian reconstruction, samples).

Reconstruction artifacts (extra frequencies at x * fundamental, may exceed sampling rate) are different from sampling/aliasing artifacts (frequencies are taken modulo the sampling rate). But they can combine (like on DS hardware).

I was making analog synthesizers as a hobby back in the 80s while studying in the University.

For this kind of circuitry I would reduce temperature drift by enclosing it into a heated thermostat kept well above room temperature. This way after initial warm up period there is very little drift.

I used to dabble with making tunes with a friend - we had access to a Juno 106, and a couple of Juno VST plugins. We'd do a bunch of takes with both, and then later we'd choose "blind" which versions to use. The real thing won every time... we tried to analyze why, but never really figured it out - though it's probably just because the music we were making was a bit wonky anyway ;)

I think a lot of "blind" preferences like this are likely due to appreciating the accidental noise introduced in the signal path of the hardware instrument. The Juno chorus in particular is/was notoriously noisy. Add to that some crappy audio cables to get the sound out of the machine and into your recording device, ground loop hum, nearby AM radio... No software emulation is going to include all that "unwanted" sound unless it's deliberating modeling it as well.

Personally I'm from the camp that likes super-clean audio, so I was overjoyed when software synths fixed all the problems that we used to have with hardware, but there's definitely a camp that really likes the "warmth" or unpredictability of the original machine's output. Sometimes I think people spend more time adding plugins to dirty up their sound than they did making the original patch in the first place.

We ran the VST synths through the same signal path as the Juno (as a test - with good DACs)... but yeah, I've long-since given up on hardware synths: they're fun, but just take up too much space. I miss combining the sounds though - most of our tracks would be 90% VSTs, 10% analogue. I think you're right though: my mission now is to try and "recreate" that 10% with plugins.

My biggest problem with software has been that it perhaps limits creativity by providing such an unlimited palette.

My first synthesizer was a Juno 60, and I owned a bunch of other vintage and modern ones over the years. With hardware, it was a whole ritual to turn everything on, each instrument had its own smell, it put me into a mood of "let's play with this machine and see what happens".

When I moved to software, I finally had all the sounds I always wanted but could never afford, I finally no longer had to futz around trying to reprogram a patch I liked, I finally could send any instrument to any effects box... but there were less happy accidents. It felt a bit more like my day job, which also just involves sitting in front of a computer.

I think it can be like that for a lot of people, where the tactility and limitations of the gear can inspire a different approach to music-making. I imagine that aspect also plays in to the emotion that some people have that hardware instruments "sound" better.

All that said, I would never go back to hardware. As you say, it's hard to beat the convenience of a laptop.

It's about the UI. Most hardware synths have one-knob-per-function on a UI the size of a large panel. You can mould the sound in a tactile way.

With a VST, everything goes through a mouse. And you'll probably spend some of your time getting distracted by moving windows around to show/hide other VSTs.

It's a much more cerebral experience.

My biggest problem with software is that it's so limited. VSTs and DAWs ape hardware studios far too literally.

I'd like to be able to connect anything to anything - including VST internals to the internals in other VSTs. And add some generative/programmed elements. But most DAWs either don't allow that at all, or they only allow it with severe limitations.

Yes, the big physical panels are what make them playable. When you learn a physical synth, you get the benefit of muscle memory, so tweaking the filter cutoff “just so” during a performance can be done almost without thought.

I’m excited to see what happens in VR. The tactile feedback isn’t there, but I bet the muscle memory is. I don’t have a VR setup, but Synthspace might convince me to get one this year—it looks better every time I check on its progress. A VR modular synth kit without the insane cost? Yes please!

https://youtu.be/l-za23kxY7E

What I find interesting is the line between an instrument and music, where does it lie? If you play piano you focus on the music played, but if you play a synthesizer the focus is much on the sound. Same applies to acoustic guitar vs. electric guitar with all them effects-boxes attached.

>We ran the VST synths through the same signal path as the Juno

Yes, but there's also noise inside the Juno at the DAC, chorus, etc.

Synth nerds are among the most ardent gear fetishizers there are. Personally I'm very happy to have my gear finally reduced to a laptop and a set of headphones.

Cannot upvote this enough. The portability is one thing. Another is reliability. I love Roland and Korg, but I purchased the last two Korg flagships and they both stopped functioning right after the warranty period. They are essentially custom computer hardware with none of the service options or reliability available in the PC/Mac world. Also Korg somehow gets their distinct sounds near flawlessly in software, even though their iPhone apps are a tiny fraction of the price of the hardware in real life.

> reliability

Pre-COVID I had a semi-regular synth jam session with a dude 100% invested in software synths. First 30 minutes (no exaggeration) of every session was him fighting with Ableton or whatever, and rebooting his Mac, trying to get something trivial to work, like MIDI clock or input monitoring.

Meanwhile I just plugged my Minilogue into the power strip and mixer and did my own thing.

There's something to be said for a musical instrument not to be joined at the hip to a general-purpose networked computing device.

Can’t argue. I love playing a Minilogue or an Electribe or a Roland JD-Xi. They are all superb instruments for jamming. And you are so right, host environments can be frustratingly buggy. On the other hand, the Korg Gadgets on iOS are pretty damn reliable.

My only argument is that with software versions you’re much more likely to get upgrades when bugs occur. And I personally will simply no longer buy a Korg flagship because of my troubles.

I think it could be worse. On the whole, synth wankers tend to be cool with modding and reissues. In constrast, it seems that guitar people ascribe magic qualities to very specific models from certain years and are paranoid about keeping these instruments as authentic as possible. With synths you have people looking at MS-20 serials to make sure it has their favored filter inside, but that's usually where the madness ends.

With guitars there's also a whole subculture of DIY modification and ecosystem of aftermarket parts to support it. It helps that Fender guitars were designed to be modular to begin with (AFAIK for easier manufacturing and repairs, the hackability was unintended), and for most components there are only a few common form factors so you don't need any woodworking skills to get started. Attempts to reproduce the exact '59 'burst sound are certainly part of the fun, but there's much more to it.

Developers model and reproduce this drift in software synthesizers because it's pleasing to the ear of many...

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