Guitar Recording FAQ: How do I achieve better separation between the sound from my amp and my studio monitors?

I’d prefer to record through my amp, but how can I hear the sound I’m getting when the amp is louder than my monitor speakers?

Marc, Maidstone

This is a perennial problem for anybody who is trying to record themselves. It can be difficult enough in professional studios but it poses even greater challenges when you’re trying to record at home. Fortunately, there are ways to work around it.

• READ MORE: Guitar Recording FAQ: How do I mic my guitar amplifier?

You touch on the fundamental issue in your question. We all recognise that optimising your guitar tone traditionally depends on turning your amp up high enough to hit the sweet spot, so you have to find ways to work around this volume imbalance.

In short, the solution is to put some physical distance between your amp and your listening room. You may not be able to achieve perfect isolation, but if you can place your amp in a different room and shut all the doors in between, it should be sufficient. Doing so, however, does have some drawbacks.

The long run

When you’re recording yourself, you have to operate your computer and any outboard sound processing equipment in addition to playing your guitar. So how can you and your guitar remain in close proximity to your speakers and studio gear when the amp is in another room? Using a very long guitar cable is the obvious answer, but there can be sonic drawbacks.

All instrument cables are inherently capacitive and the longer the cable, the more capacitive it will be. In practice, it means the longer your guitar cable, the more treble you lose. But very long cables can be used with minimal losses, so long as you place something between your guitar and amp that lowers the impedance.

You’ll doubtless have heard the phrase ‘true bypass’ from the stompbox world. However, the idea that eliminating all circuitry between a guitar’s output socket and an amp’s input socket is somehow a guarantee of superior tone is simplistic and only applies if the distance between the bypassed pedal and amp is very short.

The likes of Ibanez, Boss and Pete Cornish always understood this, which is why they employed buffered bypass circuits. A lower output impedance allows the guitar signal to travel further with minimal losses, so consider using a buffered-bypass effect, or tuner, if you’re connecting to an amp in a different room. Remember, it doesn’t have to be switched on but it does need to be connected to a battery or DC supply.

A very long guitar cable can also act as an unwanted aerial and pick up noise interference. Using a couple of passive DI boxes can help overcome this. Plug your guitar into the instrument input of the first DI box and the internal transformer will lower the impedance and create a balanced signal output.

To create a balanced output, the positive side is split in two and the polarity of one side is reversed. The low impedance/balanced signal exits from a male XLR socket on the DI box, so a microphone cable will be needed to run out to the room with the amp in it. This cable will need a female XLR plug at each end because it plugs into a second DI box placed next to the amp.

Running through the second DI box in reverse reverts to the original high impedance. It also restores the original signal polarity, thereby reinforcing the guitar signal while simultaneously cancelling out any noise that might have been picked up through the cable.

Use a short length of guitar cable to connect the input of the second DI box to the amp input and the amp should end up getting a strong and noise-free input. An active DI box with a variable output in the first position will give you control of the signal level reaching the amp and may provide superior sound quality.

Speak easy

If you run a speaker cabinet with a separate head, or you have a spare speaker cab, there’s another solution that offers many practical advantages and we think is preferable to using long guitar cables. Keep the amp section in the room with you and run a long speaker cable out to the cabinet instead.

As long as your speaker cable is of a high quality, you shouldn’t experience any loss of audio quality, and noise isn’t an issue because amplification occurs at the start of the cable and not the end. You don’t even need to spend a lot of money on cable, because regular twin and earth cable with stranded copper wires works perfectly.

Solder the live and neutral wires to a couple of quarter inch jack plugs, to the tip and sleeve respectively, ignore the yellow/green ground wire and you’re done. Remember that doubling the cable length doubles its resistance, so go with the chunkiest cable you can solder. If you prefer to buy a long speaker cable, try to go for 12 AWG or better still, 14 AWG.

Having the amp right next to you allows you to set the controls as you’re listening through the monitor speakers, so you can tweak your tone to sit perfectly in your tracks. Best of all, you won’t damage your hearing dialling in your sounds and it will save countless trips back and forth to adjust your amp. Even in big commercial studios, many guitarists prefer to play in the control room so that they can hear their guitar in the mix without having to use headphones.

Loudness war

You should also think carefully about how loud your amp needs to be. These days, a 100-watt amplifier is likely to be regarded as too loud even for outdoor festivals by some sound engineers, so it’s definitely too loud for sensible home recording. Big amps can overpower small rooms and make it almost impossible to achieve adequate separation for accurate monitoring.

Consider using a smaller amp for recording. It may surprise you that small amps can end up sounding bigger and more powerful than larger ones in a recording situation. Attenuators are also effective recording tools and will allow you to hit your amp’s sweet spot without making your neighbours want to hit you.

Additional separation can be achieved by placing cabs in cupboards or building a ‘room within a room’ by surrounding them with mattresses or sofa cushions, and covering everything with duvets. Everything except the amp itself of course, because you wouldn’t want it to catch fire.