October 2024: Fractal Audio's VP4 Virtual Pedalboard has been added to the wiki.
Cab block
Contents
- 1 Manual
- 2 User contributions
- 2.1 Global Cabinet simulation
- 2.2 Matching amp models and cabs
- 2.3 Adding room ambience
- 2.4 Low-Cut and High-Cut
- 2.5 Impulse Responses (IR)
- 2.6 IR Capture
- 2.7 Why parallel cabs are louder than a single one
- 2.8 User cabs
- 2.9 Cabinet Size Warping
- 2.10 Motor Drive
- 2.11 Frequency response curves
- 2.12 Where to put the Cab block
- 2.13 Selecting a Mic sim and Proximity
- 2.14 Air
Manual
Template:16.13 Loading User Cab IRs
User contributions
Global Cabinet simulation
If you never need Cabinet simulation, for example because you're using the Axe-Fx II for effects only or just with a power amp and speaker cabinet, switch it off in the Global menu. Presets will then have a lot more "CPU room" for effect blocks.
Matching amp models and cabs
It’s a matter of personal preference which cab to use with an amp. You can go with "historically correct" amp/cab combinations. Or go wild. The differences can be enormous. For example the 4x12 20w (very vintage, low power) has little bass, the 4x12 German has loads of it. Differences between cabs may also originate from the way the IR was captured. F.e., the 4x12 German sounds as if the mic was very close to the speaker (proximity effect). The 4x12 Brit sounds as if the mic was at some distance (thin bright tone). When comparing cabs, don't judge too quickly. Each time you select a cab, you may need to adjust the amp settings to dial in a nice tone.
In this list the 'traditionally' matching cabs are listed for each amp.
More information on speakers in this article.
Adding room ambience
Close-mic'd IRs aren't long enough to contain room ambience. The Axe-Fx II offers additional room ambience parameters in the Cab block. It's a special reverb effect. Also see Close-miked versus amp-in-the-room tone.
Low-Cut and High-Cut
The Axe-Fx II includes low-pass and high-pass parameters. These make it easier to deal with boomy or harsh sounds. Of course you can still use the the same parameters in the Amp block, or use a separate EQ block. Common settings are 80 to 150 Hz for high-pass, and 5 to 8 kHz for low-pass, but YMMV.
Impulse Responses (IR)
IR Capture
Why parallel cabs are louder than a single one
Why do Cabinet blocks in parallel rows sound louder than a single Cabinet block?
- Check this: Parallel rows with effect blocks
- Bakerman: "It depends on how you're panning. Assuming a mono signal sent to cabs: Stereo cab w/ Pan L and Pan R fully left & right will be the same output level as 2 mono cabs w/ balance L & R. If pans/balances are centered the 2 mono cabs will be 6 dB louder. Balance elsewhere would be between 0 and 6 dB louder, and balance doesn't correspond 1:1 to pan L/R for the same placement. Balances will need to be further toward -50 or 50." Source
User cabs
- If you are looking for something different than the stock cabs, take a look at 3rd party IRs. The Axe-Fx II has 50 user cab slots which can contain external IRs. Axe-Edit (or a MIDI librarian) can be used to manage IRs and to upload them into the user cab slots. The Axe-Fx II will display the name of IRs in the user cab slots. The name is contained in the sysex data of the IR file with a maximum of 32 characters. IRs can be renamed using Axe-Edit.
- The process of loading IRs is described in the manual (see above). Also, forum member Cobbler describes the process in this thread.
Cabinet Size Warping
Firmware 2.0 introduced Cabinet Size Warping. This allows the user to change the relative size of the speaker (not the cab). Only accessible if the Cab is set to Mono. Cab Size has been renamed to Speaker Size in firmware 5.
Motor Drive
- Firmware 5 release notes: "Added speaker motor modeling to Cabinet block. This models the effect of high power levels on the tone of the speaker. The Motor Drive parameter controls the relative drive level and, therefore, the intensity of the effect."
- Dialing in Motor Drive by forum member Manny Fufish.
Frequency response curves
Frequency response curves:
- http://forum.fractalaudio.com/user-cabs-irs/48552-update-axe-ii-stock-cabs-freq-response-curves.html
- Red Wirez IRs
Where to put the Cab block
In the real world it makes a difference if you put effects before or after the speaker cabinet. It's different with the Axe-Fx II.
- Javajunkie: "You can place the effects loop anywhere in the chain (just add the fx loop block). Unless you are running a stereo cab or 2 mono cabs panned hard L/R, you may want to place stereo effects after the cab. The cab is a linear time invariant effect (unless you add drive) so effects like delay and reverb will sound the same before or after it. As Cliff and others have stated on numerous occasions LTI effects can be placed before and after each other and the will sound the same. Only when placed before or after non LTI effects (drive, amps, et. al) it really matters. The one caveat there is that some effects are mono, placing effects before and after that makes a difference."
- Cliff: "The difference in having the cabinet before or after the effects is usually subtle. It depends on how non-linear or time-variant the effect is. For effects like EQ, which are linear and time-invariant, it doesn't matter at all. For slightly time-variant effects like chorus and flanger the difference isn't very pronounced. For highly time-variant effects, like pitch shifting, the difference can be marked."
Selecting a Mic sim and Proximity
- Don't underestimate the impact of the mic type on the tone. E.g., adding a R121 (Royer 121, front at 6") will add lots of highs and lows to the tone. The 57 DYN (Shure SM57) works with almost everything. Many users like to combine the Royer and SM57 for recorded tones.
- The "None" setting still involves a mic sim. All Fractal cab sims were created using a neutral Earthworks mic, placed close to the speaker (the "far-fields" are an exception, see above). So the sound is still a close-mic'd tone. But selecting "none" with stock cabs is the best way to remove the tonal influence by the mic from the tone. Also, not using a mic sim will remove a lot of low and high frequenciy content from the signal.
- Firmware 3.0 and later add the Proximity parameter. This simulates the proximity of the recording mic to the speaker. Higher numbers translate to the mic being closer to the speaker. The default setting (2.5) is neutral. When setting the mic to "none", keep proximity at its default setting.
- There's great info about using mics in the document Dialing in Your Tone by Red Wirez.
- Wikipedia:
- More information
Air
The Air parameter has been added to the Cab block. It mixes in direct signal with the processed signal. The Air Frequency parameter (added in firmware 5.04) is available for adjusting the cutoff frequency of the mixed signal.