Production tips: Exploring digital distortion and mimicking retro samplersHardware samplers of the mid-80s and 90s are utterly outclassed by modern software samplers, but there are still producers who use them religiously. Workflow is a factor, but this feeds into a more fundamental attraction: The sound.

READ MORE: How to create your own drum sample packs for hardware and software samplers

Limited bit depths, downsampling to save memory, comparatively crude processing algorithms and relatively unsophisticated analogue input and output electronics combine to give classic samplers a distinct — and often genre-defining — sonic character. Fundamentally, this is just a blended sauce of different distortion flavours.
Some software samplers can emulate these distortions to some degree but offer only limited ways to hone – and abuse – the effect for specific creative results. Thankfully, you can create your own version of this blended distortion sauce, and once you know how to do it you can make it spicier, fruitier or smokier as you see fit. You can also slather this tasty retro sauce on anything you like – software samplers, synths or live performances.
1. Input and Output Treatment

A hardware sampler’s transistor-based preamps will always have a sonic impact and, when pushed, will lean towards a gritty, hard-clipped distortion. To emulate this, add a suitable distortion at the front of your signal chain. A good option may be included with your DAW; alternatively, something like BLEASS Saturator or Kilohearts Distortion will do the trick.
Analogue to digital converters include filters to remove frequencies that could cause aliasing. We can control this stage by adding a low-pass filter to the chain. Ideally, this should be part of the input distortion processor or placed after it in the chain, but you can place it at the top of your signal chain if needed.
The output circuitry of a real-world sampler would rarely, if ever, get overdriven, but consider adding a second hard clipping processor at the end of the chain nevertheless. It isn’t essential, but it can add some realistic colour, leading to a slightly harder sound. Plus, it lets you add a bit more drive if you want. You can also add another low-pass filter here, ideally placed prior to the distortion, but it’s OK if placed at the very end of the chain.
Bear in mind that if the sound source you are using is adding reverb to the sound, then you may want to bypass this and recreate it after the distortion processing — although distorted and downsampled reverb can have a charm all of its own!
2. Simulating Digital Conversion and Processing

A sampler’s digital specification is the most important factor in the character of its sound. Bit depth is fixed for any particular sampler. The sample rate is more fluid and sampling at lower rates and applying additional downsample processing are common techniques for maximising sample memory.
Plugins that create these digital distortion flavours tend to combine both bitcrushing and downsampling. Better examples will also provide control over jittering, aliasing and/or imaging artefacts introduced by a hardware sampler’s converters and processing algorithms.
Place this type of distortion after any processing that’s emulating the sampler’s input path, and before any processing emulating the output path. We’ve decided to use SSL Digicrush because of the amount of control it gives over the details of its digital distortion. It also features a suitable input overdrive of its own, allowing us to dispense with the separate input distortion stage (we’ll retain the other input and output treatments). If you don’t have Digicrush then grab the demo to follow along; alternatively, apply the following techniques using your bitcrusher/downsampler plugin of choice.
3. Emulating Vintage Samplers

The first two iterations of the E-mu Emulator were 8-bit samplers with a 27kHz maximum sample rate, qhile its SP-12 drum machine lifted this to 12-bits and 27.5kHz. The first truly affordable sampler, the Ensoniq Mirage, was also 8-bit but boasted a 32kHz sample rate. And the samplers that started Akai’s rise to the forefront of the sampling revolution, the S900 and S950, were both 12-bit devices with 40kHz and 48kHz (respectively) maximum sample rate.
If you wish to emulate the sound of any vintage sampler, the first step is to configure your bitcrusher and downsampler to match that sampler’s specs. Artefacts such as jitter, aliasing and imaging tend to be more pronounced with older hardware, so dial in more if you’re after an early E-mu or Ensoniq sound, and a bit less if you’re chasing a classic Akai sound.
As a general rule, older units will also tend to introduce more colouration at the input and output stages, so bring in some dirt at the input and, maybe, a tiny bit at the output too. Experiment with different amounts of input drive to see what tones and harmonics come out.
4. Downsampling

To maximise hardware sample memory, it was common to reduce a sample’s rate to as low a value as possible. Going even lower can give some interesting results.
So, how low to go? There is a rule, the Nyquist frequency, that specifies how low the sample rate can be before aliasing and other artefacts are introduced. Put simply, this is twice the highest frequency contained in the sample. Therefore, bass sounds and kick drums can be taken to much lower rates than pianos or vocals before they start to get mashed up.
Load up a bass instrument and create a bassline for it, then insert Digicrush (or your preferred plugin) on the channel. Choose a bit depth – we’re going for a marginally crispy 12-bit – then, with the bassline playing, adjust the downsample frequency. When you just start to hear aliasing and degradation you’re close to the Nyquist frequency for the sound you’re using. Experiment with different frequencies to find one that gives a pleasing colouration and dirtiness.
Explore how the aliasing controls impact the results. Aliasing can enhance high frequencies, which can sound a bit incongruous on a bass or kick, so use an output filter to tame these if need be. Also explore the impact of the input drive on the overall sound.
Be sure to repeat the above using different types of sound, noticing how those containing higher frequency components will have a higher Nyquist frequency, and so will start to distort earlier as you reduce the sample rate.
5. Low Bit Depths

As well as adding a general gritty patina, lowering the bit depth both reduces dynamic range and enhances noisiness. 12-bit gives a pleasant balance between grit and clarity, and 8-bit is a good choice if you want a lot of dirt but still want the original sound to come through.
If you head much below 8-bit then noise is going to become a major component. To make this more useable, consider using your post-distortion filter to take away some of the harshness of this noise. Also, if using Digicrush, experiment with the ‘Bit Mode’ setting, as this can also calm the noisiness…
Or, unleash it: Using the un-gated ‘Destroy’ and ‘Noisy’ modes along with low bit rates can do some serious damage to your audio. You can also use this combination to create some very cool retro gaming effects – just drag the bit rate low, the jitter high, and sweep the Downsample frequency.
6. Going Beyond

Recreating a retro sampler vibe aside, one of the most interesting things about this distortion setup is how the various stages interact with, and impact upon, each other.
Load up a sound with a wide frequency range – we’re using an upright piano – and insert your distortion chain on the instrument’s channel. Dial in some strong bitcrushing and downsampling settings for a nice, gnarly digital distortion, then continue to explore the chain, pushing it and backing it off in different places to see what results you can achieve.
Notice that strong digital distortion produces frequencies and overtones that remain somewhat static no matter what it is given to chew on. Because of this, automating and modulating the downsampling rate can produce dramatic and very accentuated comb-filter-ish sweeps that sound great on pads.
Be sure to explore the interactions between the input filter and the downsampling rate, and add automation or modulation to the former as a means of adjusting the prominence of digital artefacts. And don’t forget to try different filters and distortions at either side of the digital distortion processing.
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