Genos master compressor

Posted on by

There is an on-going discussion at the PSR Tuturial Forum about the Yamaha Genos™ master compressor.

I did a little “effect sleuthing” and determined that the Genos master compressor is the same algorithm as the Yamaha Montage parallel compressor, PARALLEL COMP. This effect is part of the Montage v1.5 update. The same update added the universal compressor down (UNI COMP DOWN) and universal compressor up (UNI COMP UP) algorithms. All three algorithms can be used as a Montage master effect. On Genos, the parallel compressor is a master effect; the universal compressors can be used only as insertion or variation effects.

How did I run this down? I compared the parameter definitions for the Montage PARALLEL COMP effect algorithm against the parameters of the Genos master compressor. They match exactly. Yamaha often share effect algorithms across their top-of-the-line equipment.The Montage parameters are:

  • Type: Natural, Rich, Punchy, Electronic, Loud
  • Compression: 0 to 100
  • Texture: 0 to 100
  • Output level: -18dB to +18dB (0 to 120)
  • Input level: -18dB to +18dB (0 to 120)

The parameters for the universal compressor algorithms match up, too. However, the Genos user interface (UI) does not allow access to the 17th parameter, Side Chain Input Level. Yamaha need to remove the 16 effect parameter restriction imposed by Genos. (This restriction prevents access to the rotor ramp parameters in the new rotary speaker algorithm, too.)

If you’re a Montage person, you’re probably wondering, “What are ‘Natural,’ ‘Rich,’ etc.?” I’ll quote the Yamaha Genos Reference Manual here:

  • Natural: Natural Compressor settings in which the effect is moderately pronounced.
  • Rich: Rich Compressor settings in which the instrument’s characteristics are optimally brought out. This is good for enhancing acoustic instruments, jazz music, etc.
  • Punchy: Highly exaggerated Compressor settings. This is good for enhancing rock music.
  • Electronic: Compressor settings in which the electronic dance music’s characteristics are optimally brought out.
  • Loud: Powerful Compressor settings. This is good for enhancing energetic music such as rock or gospel music.

Frankly, I don’t know as much about audio compression as I should. Fortunately, Sound On Sound Magazine has an excellent article about parallel compression. The article has terrific background information about all forms of compression including DOWN and UP compression. DOWN compression is the conventional form that we are most familiar with.

Parallel compression puts a very high ratio (limiting) DOWN compression block in parallel with the original audio signal, i.e., it mixes the original signal and the compressed signal.

                ----------------------
               |                      |
     Input ----|                      + ----> Output
               |                      |
                ----> Compressor ---->

Massive gain reduction is applied to the loudest passages. According to SOS, “This means that at those points, its involvement in the mixed output signal is virtually insignificant; the output signal is completely dominated by the original input signal coming via the direct path. As a result, those loud but delicate transients are left completely intact and unchanged — which is the primary aim of this technique.”

No gain reduction is applied to quiet signals below the threshold. Thus, the parallel paths, direct and compressor, pass the same signal. When the two signals are summed (mixed), the quiet passage is +6dB louder. Again, quoting SOS, “this simple form of parallel compression leaves the loud bits unaffected and raises the quiet bits by 6dB, the total reduction in dynamic range is only 6dB.”

I hope this information helps. I recommend reading the SOS article; it has several graphs and goes deeper into this studio technique.

Copyright © 2018 Paul J. Drongowski

Suggestions and questions to Yamaha

The Genos manual should at least mention that the Genos master compressor performs parallel compression. A short explanation would help people apply and tweak the master compressor.

The Genos universal compressor algorithms support side-chain. How can we use side-chaining? How do we get a signal into the side-chain input?

Yamaha engineers are building effect algorithms with more than 16 effect parameters. The Genos user interface needs to provide access to more than 16 effect parameters and to store them.