KLANGHELM DC1A: COMPRESSOR WITH ATTITUDE AND THE POWERFUL 'MIX' FUNCTION.

This versatile compressor is a good reason to talk about Sidechain HPF and Parallel Compression. Download your copy now!

One of the observations I hear the most about my mixes is: " -How do you manage to get this 'punch' in the mix, especially in the drums?" The strangeness usually comes from live sound technicians, who are not used to chasing reduced dynamics in their mixes, typical of broadcast productions and the consequent new reality of the post-pandemic world where target levels of Loudness requires a compressed mix and without many dynamic variations as in my recurring case: Rock n' Roll, with guitars, bass and drums and that "in your face" voice. My answer goes through items like: Taking care of the sound of the instruments at the source, having well-crafted arrangements and faithfully performed by the musicians, bus compression and mastering limiters.

Bus compression is a process where we group several channels (instruments) in a subgroup or auxiliary output of the mixer and apply a compressor that will compress these channels as if they were a single instrument and then this signal is returned to the mix. The objective here is to apply the same dynamics to individual microphones or signals that seek to achieve a certain cohesion between them, having as its most classic case the drums, an instrument played by one person, but captured by several microphones. The compressor scaled for such a mission has to allow signals of different spectral content (frequencies) to be treated similarly and that is challenging. The kick drum for example, being rich in low frequencies, to be perceived with an amplitude similar to the snare drum, must have a large amplitude compared to this one, because our ears are somewhat insensitive to the low frequencies of the kick drum. By grouping the kick and snare channels into the same subgroup and applying a single compressor bus to them, the kick drum amplitude will be very significant and will trigger the compressor too easily and will end up riding the compression affecting the sound of other drum microphones. In the case of the DC1A, its 'DEEP' function triggers a high-pass filter, eliminating a large part of the low frequencies in the compressor's detection circuit (sidechain), thus decreasing the influence of the kick drum on drum bus compression, allowing the snare, which is the voice of the drums, to drive the compression of the kit, bringing a more uniform sound and typical of rock n' roll. Increasing the 'INPUT' level increases the program level to meet the fixed threshold, resulting in more compression. The final numbers of the program will be given by the "OUTPUT" control which has a make-up gain function.

The 'RELAXED' function changes the compression detection from PEAK mode (sensitive to signal peak values, ideal for transient signals such as drums, guitars and percussion) to RMS mode (more sensitive to RMS value, obtained through an averaging process, more suitable for long duration signals such as voice, keyboards, bass and others). The 'MIX' function allows you to perform parallel compression, without the use of an additional audio (bus) path, as required in the traditional "New York style bus compression" trick, very common among Big Apple's sound engineers in the 80's and 90's. This trick, which consisted of creating a copy of the signal in question and having it undergo a (usually) heavy compression, followed by an equalization that could enhance bass and/or treble of this compressed signal, which was, then, brought back to the mix to be added to taste along with the original signal. The result was a more aggressive mix, with more 'punch' or 'pressure' if you like. In a traditional situation, you would need one or two more channels (depending on whether the signal in question was mono or stereo) at the mixer to mix this compressed signal, parallel to the original one. Hence the name: "Parallel Compression". With the MIX control, you can simply dose how much compressed signal you want to add to the original signal, dispensing with the use of one or more additional channels to have this effect, much desired in Pop/Rock in anything: Drums, guitars, bass and vocals. Caution: This effect can be addictive (laughs).

On top of that, the DC1A even offers negative compression, with the 'NEGATIVE' function (amplification of the signal when it goes above the threshold value, very useful in another trick: Adding artificial sub-harmonics to a kick channel - but this is subject for another post) and 'DUAL MONO' mode, where the two sidechain signals (Left and Right) are unlinked. Be careful when using this function, because in stereo signals, it can cause variation in the stereo image of these signals by having more compression on one channel than on the other.

Klanghelm DC1A runs on Windows or Mac and can be downloaded for free through this link.

Did you like this tip? So share and subscribe to our blog to be notified of future news! Also subscribe to our YouTube channel for videos, tutorials, reviews and news: YouTube.com/EnginearAudio. See you next week!

From Jerusalem,

Tairo Arrabal

(Enginear Audio Solutions)