It is time we talk about impulse responses and Ola Englund helps a lot :)

It is time we talk about impulse responses and Ola Englund helps a lot :)

Time has come to at last talk about what is an impulse response, what you can do with it, and wy we speak about virtual cabinets with our Torpedo technology.

What are impulse responses? An impulse response (IR) is how a system ( a room for example) reacts to an extremely brief sound (a pulse).To create an IR, that you will be able to load in a plugin, we play a pulse, record the reaction (the response) of the system we want to recreate in our plugin, and create the IR file through mathematical treatments afterward (notably Fast Fourier Transform). There is tons of literature around the web on the math side of Impulse Response, the different techniques. The easiest way to picture an IR is through reverbs. Imagine you are in a cathedral. You clap your hand (that is the impulse), you hear the sound of the church reacting to your clapping (the response) which takes the form of its reverb. What an Impulse Response allows you to do is to play anything ( a guitar, a piano, steps,etc.) you want in this cathedral if you have the IR of this cathedral.The downside of an IR is that it is the impression of one precise position. When you are in a gigantic hall moving a couple of meters away and clapping again your hand does not change too much the way you hear the reverb. But when we are dealing with guitar cabinets, a couple of meters away is day and night in terms of sound. But wait, I was talking of how a hall would react to you clapping your hand, but an IR from a guitar cabinet?What is a guitar-cabinet-IR?Like clapping your hands in a hall and creating a response, sending a signal in a guitar cabinet creates a response from the speaker. If you take the same signal and change the cabinet, the response will be different. This is what is behind having an impulse response of a guitar cabinet. You have how it reacts to a signal. This reaction is recorded by a microphone (and preamp) to create the impulse response of the cabinet. Depending of where you place the microphone, which type of mic you use, the response recorded will change. This is why some IR sellers sends you hundreds of files for one cabinet, because each files represent one position of one mic in front of the cabinet.

Here at Two notes our cabinets makes your life much easier in terms of use. One file, and endless possibilities of mic positions in front and at the back of the cabinet. And all this in real time. No loading and checking one file per one file. You move the microphone like you would do in a real studio. And you can change the microphone easily too.

Ola Englund who is a regular Two notes' user, with either the Torpedo Live and the Torpedo Reload, has shot this great video about creating your own IR. Two notes has Torpedo Blend IR for you to create your own IRs and have them loaded into any Two notes' hardware and the Wall of Sound plugin.


  • David Rome
    14 octobre, 2018

    Thank you for this explanation.There was some reference to the technical side of things, but it was clear and concise, and only as technical as it needed to be.Now when I talk to my wife about the tools I use to create music she understands to what I am referring, what it is used for, and why it is so important.Thank you, also, for putting in the effort, and caring about the quality of the work and the products.

    • Guillaume
      18 octobre, 2018

      Well thank you for the very nice comment!GP

  • Kirill
    21 octobre, 2018

    I'm fascinated by the quality of Torpedo. I think this plugin stands far far away from any other plugin in the world. And this is rediculous that vet few people know about this plugin. I found it by chance just by searching in Google about the Wall of sound techiques invented by Phil Spector. I wanted to ask to explain what does it mean 20000 positions per mic. Did you capture the impulse 20000 times?

    • Guillaume
      25 octobre, 2018

      Thank you for the kind words. We do not capture each and every position, but we use a special algorithm to synthetize the sound at a certain position. ;)

  • Vasily
    30 octobre, 2018

    I have a few of questions: 1) I read sometime ago at Gearslutz that your approach with Virtual Cabinets is somewhat similar to dynamic convolution, like Nebula products family (by Acustica Audio) does. Is that true, or use a regular static IR's approach?2) In another comment you mentioned that you actually do not measure 20,000 positions of mic. How does the approach for gathering a response look like in the case of Virtual Cabinets? Do you just use some predefined positions, like on-axis, off-axis, far, etc. and the interpolate the sound between them? Or you measure just a one position, and the rest of the positions are simply some frequency filters/EQs?3) Do you implement some phase compensation when several mics are used on a virtual cabinet?Thank you!

    • Vasily
      23 novembre, 2018

      @TwoNotes - any chance to receive a reply to my questions? Thanks!

  • Two notes
    23 novembre, 2018

    Hello Vasilysorry for the delay in the aswers.we use convolution to do our virtual cabinets and we do measurements in specific places and then it is interpolated. kind regards.