This article covers line-level equipment, like synths, keyboards, preamps, and mixers. For instrument-level equipment, like guitars, refer to this article: I'm getting little or no signal from my guitar/instrument-level equipment. For microphone-level equipment, please see this article: I’m getting little or no signal from my microphone or mic-level equipment.
If you are having problems getting signal into your audio interface or preamp from your line-level equipment, we've put together some steps for you to try to fix the problem.
To be certain your equipment outputs line-level, check with the manufacturer, and have a look at this article for more information: What are the differences between mic, line, and instrument level?
Ensure you're using the correct connector and input
The line inputs on most of our products use 6.35mm (¼") connectors, but some use other connectors. Refer to the user guide if you aren't certain which connectors your line inputs use: Focusrite Downloads.
If your interface or preamp has combo ports that accept both XLR and 6.35mm (¼") jack connectors, only the central 6.35mm (¼") jack section of the input should be used for line input.
If your line-level equipment uses a different type of connector to the inputs on your Focusrite interface or preamp, you can just use an adapter or a cable with the different connectors at each end.
Mono vs stereo
In almost all cases, the line inputs on Focusrite products are mono, so two inputs need to be used for stereo signals. So if your equipment outputs stereo via a single cable, you will need a splitter, otherwise, one channel stereo signal can be lost and the signal may be degraded.
Line vs instrument inputs
It's important to be aware that some line-level inputs on our products are also instrument-level inputs.
If you connect line-level equipment to an input that is configured for instrument-level, it will likely overload and distort the input, as the two signals have different electrical characteristics: What are the differences between mic, line, and instrument level?
Make sure INST, instrument, Hi-Z, or any other instrument-level settings are disabled— you can refer to the user guide to confirm how to do this: Focusrite Downloads.
Line-level connected via XLR
The XLR inputs on most Focusrite products are intended for microphone-level signals only. Mic inputs are not suitable for line-level signals, as the two signals also have different electrical characteristics: What are the differences between mic, line, and instrument level?
If you connected line-level equipment directly to a mic input, it could overload it and distort.
DI boxes — converting line to mic-level
Certain DI boxes can handle line-level signals, and you can connect these via XLR to a mic input. This would only really be useful if you had a dedicated mic-only preamp and needed to connect a line-level signal — most Focusrite devices have a line input option for every channel.
RCA S/PDIF inputs
Although RCA connectors can carry line-level signals, current Focusrite products do not use them for analogue input. If your interface or preamp has RCA ports, they are probably for digital S/PDIF, and aren't compatible with analogue audio.
So, if you need to connect a device with an analogue RCA output to your Focusrite line inputs, you'll need an adapter or cable that goes from RCA to the connector used by your line ins (e.g. 6.35mm (¼") jack).
Remove anything else from the signal chain
We recommend you connect the line-level equipment directly to your audio interface or preamp while you troubleshoot this issue. Doing so will rule out any effects units or other gear in the chain as potential causes.
Ensure the gain is set appropriately
Some line-level signals require a boost from your preamps to produce a strong signal, known as gain.
If the input you are using has a gain control, it should be set so that when there is a signal from the line-level equipment, the gain halo or gain level meters are consistently green. It should only turn amber at the loudest points, if at all, and never red.
Fixed Gain Inputs
Fixed gain inputs do not have a gain control; they are set at a level that should be suitable for most standard line-level gear. The input level cannot be increased with gain, but you can always boost it in your DAW or other software. However, for the quietest signals, you may need to use an external preamp prior to the line input.
Pads, boosts, and reference levels
Standards for line-level can vary greatly, so some preamps simply have a very wide dynamic range to handle loud signals, and a large amount of gain available to boost quiet ones. Others have pads to reduce the level, boosts to increase it, or controls for changing the reference level for different inputs. Take a look at your user guide if you are unsure which features your interface or preamp has: Focusrite Downloads.
Check the input is working
To make sure the input on your interface or preamp is working:
- Turn the gain control up to at least halfway.
- Insert and remove the 6.35mm (¼") jack.
Does the gain meter on the hardware or in software flash when connecting and disconnecting the jack?
- If the gain flashes, it’s likely the case that the input is working — the issue is probably related to the instrument or cable you are connecting it with.
- If not, there may be an issue with the input — test a different input, or a different interface or preamp altogether.
Check the line-level equipment is set up correctly
Is it switched on?
Obvious, but worth checking. Make sure the line-level gear is powered up. Try charging or changing the batteries if it runs on battery power.
Is the volume turned up?
Make sure nothing is muted and all the volume controls on the line-level equipment are turned up.
Test Different Setups
Test a different cable
If you still aren't seeing or hearing a signal, please test a different cable.
Test a different instrument
Next, test a different piece of line-level gear. If you don’t have one, see if you can borrow one, or take your interface or preamp to a local music store to test it with something there.
You can also test the preamp with a mic or instrument-level device to see if these are working.
Test a different preamp
Test your line-level device and cable with another audio interface, a mixing console, or another preamp. If you don’t have one, see if you can borrow one, or take your line-level device to a local music store to test it with another preamp there.
If this article hasn't helped you, please feel free to search again at the top of this page or, to contact support, please click here.