For this video, I’ll rank 7 free limiters from what I think sounds decent to what sounds the best to my ear.
EasyLimiter by EmRys is a versatile limiter, with one major flaw design-wise in that it doesn’t allow you to control the input gain. That said, you can create stereo independence, adjust your release time, change the limiting threshold, and select 4 different settings that alter the lookahead and attack.
Using plugin doctor, which I’ll use for the rest of the video to observe various aspects of each plugin, we can see how the different settings result in different amounts of harmonic distortion.
As for the dynamics, the ceiling is a brick wall.
Limiter doesn’t have the fullest sound in my opinion, but it does some nice versatility and low distortion. We get a threshold, release ranging from 1 to 500ms, input and output gain, as well as a meter on the right which indicated how much attenuation is occurring.
As for harmonics, we get more distortion at lower frequencies which is to be expected, and the ceiling is brick wall, with a very slight non-linearity.
The controls on the W1 limiter are simple; however, you can achieve an impressive sound with it. We can control a threshold, a release ranging from 1ms to 5 seconds, a ceiling, and an adaptive release which is where a lot of this plugin’s value comes from in my opinion.
As for harmonics, we’re getting moderate distortion, with some unfortunate aliasing distortion causing comb filtering. The ceiling brick wall with a slightly soft knee.
Frontier is a pretty well-known free limiter that utilizes automatic makeup gain, and program-dependent limiting to create a unique and aggressive sound. We can control how the input is monitored, the general release time, threshold, output, and a soft clip function which increases perceived loudness and distortion.
When soft-clip is on, we get a high-frequency resonance filter, which amplifies when the threshold is lowered. The harmonics are pretty aggressive with the plugin, and as you imagine, become more prominent when engaging the soft-clipper.
The ceiling is brick wall, with a slightly soft knee.
This next entry is cheating slightly since it’s isn’t exactly free, but the demo version offers full functionality - that said, it’s still best to buy the plugin if you enjoy it. With Barricade we get a compressor, and limiter - the latter offers attack and release, gain, and a ceiling.
Furthermore, we get true peak detection and metering. Although the sound of this limiter isn’t my favorite, when combined with the analog tape setting of the compressor,it has a pleasantly full and detailed sound.
Interestingly, the gain and limiter ceiling will affect the frequency response, as will the compressor settings so keep this in mind. The plugin is pretty clean when it comes to aliasing distortion - and the harmonics are at moderate levels. The ceiling is brick wall with a slightly soft knee.
Limited Z has a great sound that rivals a lot of paid limiters. Modeled on the FabFilter Pro L2, we get multiple algorithms that vary in timbre, ISP, a limiting threshold, ceiling, and interestingly a learn function that adjusts the gain according to the incoming signal.
The lowest frequencies are attenuated with a highness, which is probably used to slightly increase headroom. The harmonics are moderate, but the aliasing is a bit aggressive - each algorithm offers different harmonic formations, with Deep being the lowest distortion.
Each algorithm introduces a slightly different knee, but the ratio is always brick wall.
Last up at number 1 is limiter No.6, a fantastic sounding limiter with a lot of versatility. It offers a compressor, peak limiter, high-frequency limiter, clipper, and output section where a ceiling, output, and detection can be set. The limiter can utilize 4 different modes.
These include brick wall, soft limiting, mid-side, and multi-band, which is truly impressive for a free plugin. We can also adjust the linking of the left and right or mid and side, the release speed, and the general behavior of the limiter. Up top, we can use minimum or linear-phase processing and introduce oversampling.
This plugin actually has a significant effect on the frequency response, with the limiter mode function having the greatest impact on it. Harmonics are aggressive and become more so when using the clipper. 4x oversampling keeps the aliasing down, while the limiter type has the greatest impact on harmonic formation.