Torpedo BlendIR: Capture Tutorial
The BlendIR software is a simple but powerful tool to make professional impulse responses compliant with the Torpedo.
- A MAC or PC computer with an ASIO/Coreaudio soundcard embedding at least one line output and one line input. In an ideal case, the soundcard can go 24bits/96KHz with the best signal/noise ratio and THD.
- A power amplifier that can work at 250W/8ohms with the lowest possible distortion, linear frequency response and the lowest possible output impedance. A solid state studio monitoring amplifier fits perfectly for this task. A Tube guitar amplifier could be a fun thing to try, but as they are everything but linear the result may be... fun.
- A cabinet you want to capture
- A microphone you want to capture
- A microphone preamplifier you want to capture
- A room were you can play loud !
Here is how it goes:
BlendIR will send a test signal through the whole cab-miking setup and record the result. After some calculations, it will create a .tur file that you will upload onto your Torpedo. The whole process can be completed in under 5mn.
Phase 1, BlendIR:
Download and install BlendIR
Launch BlendIR, choose the driver you want to use (File menu/Audio drivers/OK to save and quit this window). The recommended frequency is 96KHz, the latency must be high enough in order to avoid any overloading of your CPU. We recommend ASIO or CoreAudio drivers.
The hardware IO settings window will be displayed. You need to select the appropriate routing configuration, depending on your Soundcard.
- The Main Out is used to listen to the processed sound.
- The Capture In is the recorded channel. This channel needs to receive the signal coming from the microphone preamplifier.
- The Capture Out is used to send the test signal, a 1-minute sinus sweep.
For example, one can use the Soundcard's Line Output 1 as Capture Out, the Line Input 1 as Capture In, and the Main 1&2 as the Main Out.
If you only have a unique stereo output on your soundcard, you can select the same output for Capture Out and Main Out. When the Capture process is launched, the Main Out will be muted.
Phase 2, setting up for recording:
Plug a cable from the soundcard's output 1 to the monitor amp's input.
Plug a cable from your amp's output to your cabinet. Please check the amp's output impedance, with regards to the cabinet's impedance.
Place your microphone the way you want in the record room. Do not forget that the mic's placement cannot be changed once it is in the Torpedo, that is, when you are using a user's IR — so take your time to make several measurements and find the right spot.
Plug a cable from the microphone to a mic preamplifier. Please note that the preamp's response will be also captured, and that changing the preamp may thus change the overall sound.
Now plug a cable from the preamp's output to the soundcard's line input 1.
Phase 3, levels:
It is important to note that the level of the test signal going through the cabinet matters. Based on our experience, we recommend playing at "rehearsal level", in other words at the level you are used to when recording/playing. The point is to be as close as possible to the real conditions.
WARNING: Playing at very loud levels may cause permanent damages to your hearing. The test signal is very energetic, so please use the "Play test signal" function of the BlendIR, starting with low levels, before you crank up the amp.
The bargraph on the Capture window should be between -16dB and -12dB to match perfect gain adjustment.
Phase 4, creating the file:
On the Capture window, click on the "CAPTURE" button. First try to "Play test signal" (read above), and "Start capture". Choose a destination for the file; the best is to select the Impulses directory of Torpedo Remote so you can load the captured IR into your Torpedo afterwards.
The signal is called a sinus sweep. The signal will sweep from the ultra low frequencies to the highest and even after the cabinet has shut. Please do not make any noise until the test is complete. Please control that there is no glitch/clic/pop in the sound that could be a consequence of a latency parameter set to low. If you hear this kind of noise, please increase the latency.
The measuring process takes 1 minute, a pop up message will warn you when it is complete.
Your computer will process the raw data to create a proper .tur file in the previously selected location. This process may take a few minutes, depending on your CPU power.
Phase 5, uploading the file:
Launch the Torpedo Remote software.
Go to the menu File/Memory Management, click on the User tab.
On the left side you should see the newly created impulse, and on the right the locations on the Torpedo where to upload it. Drag & drop the .tur file to the appropriate memory slot on the Torpedo. You may drag several .tur files at once, select a location for the first one and the others will follow.
Once you are finished, quit the Memory Management window and enjoy your new personal cab.