Install
Run the installer. VolumeKeys appears in the menu bar. No Terminal and no complicated setup.
SSL 2 family · Tested with SSL 2+ MKII
Control compatible stereo outputs on your SSL 2 family interface with your Mac's F10-F12 keys. Tested in our studio with SSL 2+ MKII. Use every feature free for 7 days on your own Mac before you decide.
Interactive VolumeKeys preview. Device names and output pairs shown are illustrative; exact choices depend on the device, driver and macOS configuration.
More than volume
Control a compatible SSL 2 family stereo output with F10, F11 and F12. Switch between available output pairs for different monitor sets, check mono, audition the low end with Bass Focus and reduce bass spill with Bass Night, all from the keyboard.

Tested with SSL 2+ MKII
In our studio test, VolumeKeys selected the SSL 2+ MKII as a Core Audio target and the chosen route responded to mute, volume down and volume up. The free trial lets you confirm the SSL model and output pair on your own Mac.
45-second product tour
See how VolumeKeys controls a selected Mac playback route with F10, F11 and F12 and stays quietly in the menu bar.
The product tour demonstrates the same VolumeKeys workflow across compatible interface families.
How it works
Install VolumeKeys, choose your SSL 2 family interface, and keep using your Mac the way you already do.
Run the installer. VolumeKeys appears in the menu bar. No Terminal and no complicated setup.
Select your SSL 2 family interface and the stereo output pair shown by VolumeKeys. Available pairs depend on your model, driver and macOS configuration.
Press F10, F11 or F12 to mute, turn down or turn up. That’s it.
VolumeKeys with your SSL 2 family interface
VolumeKeys controls the selected Mac playback route. The SSL MONITOR knob, direct monitoring and recording gains remain untouched.
Digital monitor controller
When the device and driver expose more than one compatible stereo pair, VolumeKeys can remember a separate level for each available pair and switch between those selected routes.
High-precision 32-bit floating-point volume processing designed for transparent monitor control.
Digital attenuation
VolumeKeys attenuates the routed Mac signal and is not designed to add gain above the source level. Set your interface or monitor control for the physical listening level you want.
Private by design
Your audio is processed locally and is not sent to our servers by VolumeKeys. The app contains no ads or app-usage analytics.
Controlled changes
VolumeKeys fades device and output-pair changes through silence, then returns to the level saved for your SSL 2 family interface. Each available pair keeps its own remembered level.
Hear both channels together to spot phase and balance problems.
Focus isolates everything below 150 Hz for precise low-end decisions. Night focuses its processing where bass becomes physical. A purpose-built low-frequency DSP algorithm reduces the deep energy that makes rooms and walls vibrate while keeping the musical body of the mix intact. You hear a full, balanced sound at night, while less bass travels next door.
Follows the active hardware/DAW buffer without a second competing setting.
If the selected interface or display disconnects, VolumeKeys automatically returns system playback to the current macOS default output.
Recording
Select your SSL 2 family interface in your DAW for recording. VolumeKeys can control normal Mac audio at the same time.
Global shortcuts
Switch monitor pairs, toggle VolumeKeys, check mono and audition both bass modes from anywhere on your Mac.
Only available output pairs get a shortcut. Each global shortcut is registered independently, so a conflict on one shortcut does not disable the others.
Why VolumeKeys helps with the SSL 2 family
An SSL 2 family interface can play Mac audio perfectly while macOS treats its USB output as fixed-level. When the device does not expose a settable system master volume, the menu-bar slider and F10–F12 may be unavailable.
VolumeKeys supplies a software-controlled route before the audio reaches the SSL. It changes the routed Mac playback level while the interface’s hardware knob, monitor mix and recording path keep their own jobs.
7 days free.
Use every feature free for 7 days on your own Mac, then decide in your own time. No payment details are required.
7 days free. Just download. No payment details required.
SSL 2 family FAQ
Understand the difference between routed Mac playback, the MONITOR knob, direct monitoring and DAW input levels.
VolumeKeys is designed for compatible stereo Core Audio outputs across the SSL 2 family. Our documented studio test used SSL 2+ MKII; the complete 7-day trial lets you confirm your own SSL 2 family interface and playback pair.
VolumeKeys shows the stereo output paths available through Core Audio so you can choose the pair used for system playback. The exact names and options depend on the SSL driver and your configuration.
No. Keep using the hardware knob to set the physical listening range. VolumeKeys adds convenient digital changes for routed Mac playback and is designed not to boost above unity.
No. Direct monitoring happens inside the SSL, and recording input gain remains on the interface. For recording, select the SSL directly in your DAW.