Many of us use USB adapters, hubs, and KVMs to declutter setups, provide extra ports, and add compatibility between our devices. But with USB already prone to misconfigurations, adding extra components to the system leads many people to question whether a USB hub, adapter, or KVM could affect USB performance.
How do these devices affect USB performance, and what can you do to minimize possible performance penalties?
USB Performance Metrics
USB hubs, adapters, and KVMs can affect USB performance in various metrics. Some of the most important metrics affected include:
Now that you understand these performance metrics, let’s talk about the impact of USB adapters, hubs, and KVMs can lower USB performance in terms of latency, power delivery, and data transfer speeds. Let’s start with USB adapters.
USB Adapters
There are two types of USB adapters. These are the digital-to-digital adapter and the analog-to-digital adapter/digital-to-analog adapter.
Digital-to-digital USB adapters link two digital devices together. These USB adapters often utilize short cables, connect devices on a one-to-one ratio, and don’t do any extra processing to the signals they transmit. Due to the simplicity of the connection, these USB adapters aren’t known to affect USB performance as long as they are rated to support more recent versions of USB.
Another type of adapter is the analog-to-digital USB adapter. These adapters link and process analog signals for digital USB devices. They often adopt audio-related equipment using analog connections such as XLR, RCA, and TRS used in the popular 3.5 mm audio jacks.
AnAnalog to Digital Converter (ADC) or Digital to Analog Converter (DAC)is used to process the analog signals into digital for our USB devices. As long the adapter is rated with the same USB version of the devices, you shouldn’t notice any drop in bandwidth or power. However, you may still feel a bit of latency due to the extra processing needed in converting signals.
USB adapters do little to affect USB performance. However, analog-to-digital USB adapters can still add enough latency for time-sensitive applications such as studio recording and gaming. It is always best to connect your devices to analog ports instead of USB if available. Keep in mind that USB interfaces and mixers always have direct headphone monitoring ports. verify to use them when available to experience the least amount of latency possible.
A USB hub is a device that expands the number of USB ports available on a computer or other host device. It allows you to connect multiple USB peripherals, such as external hard drives, keyboards, mice, and printers, to a single USB port on your computer.
USB Hubs can significantly impact USB performance regarding latency, power delivery, and data transfer speeds. This is because each USB port on our computer can only be connected to a single USB controller. This controller handles data transfer, control signals, and power management.
Since USB Hubs connect to a single USB port on a computer, all the USB expansion ports provided by the hub share a single USB controller. This splits the controller’s bandwidth, which can heavily lower USB performance. The level of impact will depend on how many devices are actively using the USB hub.
Furthermore, some USB ports in computers already share the same controller. Overloading a USB hub will also affect the performance of other USB ports sharing the same controller.
To limit any performance penalties you get by using a USB hub:
It’s also worth avoiding filling up every single USB port unless it is really required.
KVM (Keyboard, Video, Mouse)
A KVM switch is a hardware device that allows a user to control multiple computers using a single set of peripherals, typically consisting of a keyboard, video monitor, and mouse. KVM switches are useful in situations where a user needs to manage multiple computers but doesn’t want to use separate sets of peripherals for each one. Although there ismulti-system wireless KVM software, having a physical KVM switch ensures better performance.
However, physical KVMs can still affect USB performance depending on the type and how it’s set up. KVMs with the same number of inputs and outputs typically don’t affect USB performance. However, some KVMs are configured to have single inputs for each computer and multiple outputs for peripherals. These types of KVMs will affect USB performance because all your peripherals are essentially using the same USB controller.
Aside from KVM itself,there are USB cable length limitationswhen setting up KVMs. The recommended cable length for USB 2.0 is 16 feet (5 meters), while USB 3.0 and above is less than 9 feet (3 meters). Since KVMs require an input and output cable for each peripheral, using a 2-meter cable for input and another 2-meter cable for output would mean a total of 4 meters in cable length. And since modern KVMs use USB 3.0 and above, having 4 meters of cable is already over the recommended length.
Still, going over a meter in cable length won’t likely have a significant effect on power and data transfer speeds. However, latency could still be a problem, especially for FPS gamers, where the added milliseconds of input lag are much more apparent.
Ensure your KVM doesn’t degrade USB performance by observing the following:
The other consideration is the quality of the hardware you buy.
Don’t Cheap Out On Hardware
USB hubs, adapters, and KVMs do affect USB performance. However, the decrease in performance is often negligible as long as these devices are rated with the latest versions of USB, are made from quality materials, and have been properly set up. So don’t cheap out on KVMs, adapters, and hubs when buying one for your setup. Don’t skimp out on cables, either. Having low-quality cables rated at USB 2.0 will only bottleneck your whole connection. Get one using the latest USB version and get the shortest cable your setup allows. Finally, read the manuals for using a hub, adapter, or KVM in your system; setting up USB connections is much more complex than many of us would think.
