Recording Guitar Amps At Home: Amp Type, Mic Type, Mic Position

 

For me, electric guitars are still a major part of most music I write. But getting the sound of the guitar amp to translate accurately into the recording can be tricky.

There are lots of factors to take into account. From the size of the amp, to whether you record it with a microphone or not, to the microphone type and placement. All these things will affect the sound that is recorded. I will try my best in this article to explain each of these elements. Allowing you to get a great sound when recording guitar amps in the home studio.

 

The signal chain 

 

The basic signal chain for recording instruments in the home studio is the same as I have explained in previous articles. Nevertheless, I will go through it again here for completeness.

You can plug your guitar into an audio interface with built-in pre-amp (such as this one) via a standard 1/4 inch jack ‘guitar cable’. The audio interface is then connected to your laptop usually via USB allowing the guitar to be recorded in a digital audio workstation (DAW). This is a cheap way to record electric guitar if you don’t have an amp in your home studio. But, it is widely accepted that if you want to get a professional sounding recording, you should record the sound from an amplifier via microphone. The fact the sound has to interact with the environment (the air and room surfaces where you are recording) brings it to life.

For this, the signal chain is virtually the same but you add a few extra elements (and therefore cost and space). These extra elements are an amplifier, a speaker and a microphone/microphones to record the sound. The microphone(s) are then plugged into your audio interface and subsequently into your laptop or PC where the sound is captured in the DAW, in the same way as above.

 

What size/ type of guitar amp is best for a home recording studio?

 

The size of the amplifier is less important than getting an amplifier that has a tone quality that you like. But in the home studio, budget and space are often a concern. Don’t worry, there is no need to spend all your money on a huge amplifier and speaker cabinet that you might see your favorite band using on stage.

 

Head and Cabinet Vs Combo Amp

 

There are two categories of amps that you may come across when shopping around.

The first is the head and cabinet type. This is where you have the ‘head’ which is the amplifier but with no speakers. The head contains all the circuitry associated with creating the guitar sound. This includes the tone settings, valves, reverb etc. The amp itself has no way of making an audible sound. For this you also need a cabinet. The cabinet is where the speakers are housed. Where the signals sent from the head are converted into an audible sound. Neither of these parts works without the other.

So although most people talk about a guitar ‘amp’ what they are most likely talking about is actually an amplifier and speaker.

A combo amplifier is where the head and cabinet have been combined into one single unit. This is usually a cheaper solution, taking up much less space. A potential downside is you don’t get the flexibility that a head and cabinet provides. You can, for example, upgrade to a bigger speaker at a later date if required.

There is no correct and easy answer here unfortunately and it is down to personal taste and budget. I would therefore recommend that to find the right model, that you go to a music store and ask to test a few out.

Check out my recommended gear section for a few options I love to help you get started.

 

How big does the amp need to be?

 

A smaller speaker size will mean less low-end frequencies and you will get a more trebly/ bright sound. So I would avoid anything too small. With larger speakers, you will get a lot more low-end which will mean the sound will travel a lot further. Potentially annoying the neighbors, a common concern in the home studio. Unsurprisingly, the amp with bigger speakers will probably cost more money too.

With that in mind, I usually recommend going for something in the middle. This should be affordable and provide a good range of sound frequencies. 10 or 12-inch speaker cones should do the job fine.

I recommend a cabinet or combo amp with at least two speakers to give you more flexibility when micing it up. Having two speakers will allow you to place one microphone in front of each speaker, using the techniques I will come onto later in this article.

 

Valve vs Solid State?

 

Valve amps or tube amps as they are sometimes known, amplify the signal using vacuum ‘tubes’ within the amplifier. A solid-state amplifier, uses ‘solid-state’ electronics to amplify the signal.

Many guitarists swear by valve amplifiers as they are known for their warm tones. However, it is worth bearing in mind that to get the true warmth and effect from a valve amp they need cranking up to quite a high volume. So if you don’t have the luxury of being able to play at high volumes, then it is probably not worth spending lots of money on a valve amp.

Knowing whether you are looking at a solid state amp or a valve amp is important as the ‘wattage’ is not comparable between the two types. A 20W valve amp is much louder than a 20W solid state amp.

Again, try a few out, see what you like and what your budget can afford.

 

Recording a guitar amp using microphones

 

Type of microphone

 

There are lots of different techniques you can use for mic-ing up your guitar amp to try and get that live sound. The sound you get will depend on the type of microphone, the number of microphones you use and the position of those microphones.

 

Dynamic Microphone for guitar amps?

 

There is not only an industry standard type of microphone used to record guitar amps but an industry standard model of microphone. This is the Shure SM57. Why is this?

 

 

The SM57 is a dynamic microphone. Dynamic microphones are the oldest types of microphone and therefore perhaps the most primitive in their design. In simplified terms, they work by having a diaphragm attached to a metal coil suspended between two magnets. A sound wave hits the diaphragm causing it to move and producing an AC current to mimic the sound wave.

Due to their design. Dynamic microphones are quite rugged and are capable of withstanding reasonably loud noises. This has lead to the SM57 being a great option for use on live guitar amps which are likely to produce some high volumes. From there, they have found their way into the studio as the standard recording microphone for guitar amps.

 

With the SM57 you will get a reliable microphone and a decent enough sound without having to spend too much money. So I would recommend starting with one of these and then maybe looking at other options when money and knowledge allow.

That doesn’t mean you can’t experiment with different microphones. Particularly if you own them already. Dynamic microphones such as the SM57 are great at picking up the main mid-range frequencies of the guitar amp. And mid-range frequencies are the most important part of a guitar sound in the overall mix. But they do tend to miss some of the lower-range frequencies.

 

Condenser Microphones for guitar amps?

 

In an attempt to try and capture the full frequency range (from the deep low ends to the brighter high ends) try using a large diaphragm condenser microphone.

Condenser microphones are typically more expensive than their dynamic counterparts and are more delicate. This means they are not ideal in a live setting but can work fine in the home studio. Especially in combination with a dynamic microphone.

 

Ribbon Microphones for guitar amps?

 

The final type of microphone you may come across are ribbon microphones. These are the most delicate and also often the most expensive microphones available. You probably don’t want to be spending this much money until you get a lot more experienced and you are starting to get fussy over your tone. It is true you can get some awesome sounding guitar tone through a ribbon microphone but it will cost you.

 

Microphone positioning and placement for guitar amps

 

Now you have your microphone or microphones, you need to know where to put them in relation to your amplifier and speaker.

 

Simple setup with single dynamic microphone

 

When starting out in the home studio my advice is to keep things simple. Not only will this save you a lot of headaches. It will save you a lot of time and money and allow you to get stuck into what you really want to do…..record!

Following this advice, I recommend starting with just a single dynamic instrument microphone. Such as the Shure SM57 mentioned above.

The general rule of thumb is that the ‘brightest’ tone coming from the speaker cone is right at the centre.

So if you have a small amplifier with only one speaker then place your microphone in a floor mic stand and point it towards the speaker. The microphone should be a couple of inches back from the amplifier ‘grille’ and not right up against it. It is unlikely you will want the brightest tone, as mentioned above. So move the microphone a touch to the left or right of the centre of the speaker to counteract this.

Put on a pair of monitoring headphones plugged into your laptop or computer to hear the sound the microphone is picking up. Not just the sound direct from the speaker itself. You can then play with the position of the microphone in relation to the centre of the speaker. Altering the distance to the speaker until you get the sound you desire. A good trick is to send a pre-recorded audio track into the amp through the direct input. This allows you to move the microphone around whilst listening through the headphones. Saving you from having to play a chord and then move the microphone, then play another chord and so on.

 

Using more than one microphone

 

As you get more confident and want to get more complex tones in when recording your amp, you may want to add more than one microphone. The problem when you add a second microphone is you have to be careful of an issue called ‘phase cancellation’ or ‘phasing’.

Phasing is an issue that occurs when your two microphones aren’t picking up the sound waves in-sync.

So if you imagine you have microphone 1 slightly further away from the speaker than microphone 2. The sound waves will take ever so slightly longer to reach the diaphragm of microphone 1. The video below shows the issue of phase cancellation visually:

 

 

 

So this is an issue to be aware of and something to look out for on your recorded tracks.

Phasing aside, there are many advantages to using more than one microphone to record your guitar amp. You could use two dynamic microphones, one as described in the last section (just off center in front of the speaker cone) with a second at the rear of the amp. By placing a second microphone at the rear of the amp you will pick up a lot of those low-end sounds that are often lost.

A second technique might be to use a dynamic microphone in combination with a condenser microphone. The condenser placed slightly further back from the speaker. The condenser microphone will add a bit more depth and warmth to the guitar tone.

 

Isolating the guitar amp when recording

 

If you’ve ever been to (or seen pictures of) a professional recording studio. You will notice that the mixing desk is usually isolated from the recording room by soundproofed glass.  This allows whoever is doing the mixing to hear what is actually being recorded without the distraction of hearing the live amp sounds.

In the home studio, we often have to get a little creative here because a lot of the time we are recording alone, and not many of us have the luxury of a soundproofed mixing room (maybe one day!). One solution is to get a long microphone lead (like this one) and then place your amplifier and microphones outside the door. In a hallway for example. This is not ideal, but should help you hear the recorded sound correctly in your headphones.

 

How loud do I need to record my guitar tracks?

 

I used to assume that I had to have my amplifier turned up to a similar gig level volumes before recording. But this started to anger the neighbors. The reality is you don’t necessarily need to play at window shattering volumes to get a decent recording.

The volume level needs to be loud enough for the speaker cone to be working and moving but it doesn’t need to be ridiculously loud. This is particularly true if you are using a condenser microphone which is more delicate and won’t be able to handle really high volumes.

One caveat to this is if you are using a valve amp. As I mentioned earlier in the article, a valve amp needs to be played loud to get the true warmth and tone to come through. So I’ll leave that will you, do you value your relationship with the neighbors more than you value a great guitar sound?

 

Recording distorted guitars

 

I am going to write a full ‘in-depth’ article on recording distorted guitar amps but I will do a quick summary here too.

 

You would think that recording distorted guitars would be more difficult than clean guitars. However, that is not always the case. Yes, it can be trickier to hear chord changes and subtleties when playing with distortion. But actually getting a good recording sound, it can actually be easier.

Distortion is basically the same as compression and so your levels are going to be a lot more consistent. This is the reason why the higher you turn the distortion the harder it is to tell the difference between notes (the reason I used lots of distortion when playing in a band!).

The main piece of advice when recording with distortion is to start with low levels of it and turn them up as you get more confident.

If you are using a valve amp remember what I said earlier. Unfortunately for your neighbors to get the best tone you are going to have to crank it up!

For everything else, it is a matter of following the same steps as above. Experiment with different microphone placement and different microphone combinations. Then make sure you don’t have phasing. Make sure you adjust input gain levels when switching from clean guitar so you don’t get clipping.

 

How to record guitar amp without a microphone

 

Now it is possible to record your guitar amp using a line-out cable directly into your interface rather than using a microphone. Pretty much all amplifiers will have a ‘line-out’ often located on the back. If not, they will at least have a ‘headphone-out’ output which serves the same function. This basically bypasses the speaker. You can then plug a cable from this output directly into your audio interface and you can record away.

This method has the advantage of being more convenient as you don’t have to worry about the microphone placement etc. It also has the advantage of being cheaper. As you don’t have to buy any microphones.

The final advantage is you can record late at night or without disturbing someone. If I have an idea and I want to get a rough demo of it down. I will use the direct output from the amp straight into the audio interface and DAW to get something down.

The truth is though, you won’t get the same life and tonal quality to your sound by recording straight through the line-out. It will sound a bit sterile.

There are some things you can do to try and add more life to the sound. You can add effects within your DAW; anything from reverb to echo to distortion to make the sound more interesting.

With everything in the home studio it is a matter of personal taste and opinion. By all means, experiment with this method and if you get something sounding good, there is no problem with that.

 

Other Bonus Tips When Recording Guitar

 

Don’t Be Sloppy

 

It can be all too easy to slip into the mindset of ‘it’s only a home recording so it doesn’t matter if it isn’t perfect’. This is no longer a good excuse. The quality of recording achievable at home should be right up there if you do things right. So once you have spent all the time following the setup steps above, don’t start getting sloppy!

By this I mean the basics:

• get new strings for your guitars often so you get the nicest and brightest sound possible.
• make sure your guitar is in tune. Check between each take that no strings have slipped out of tune. This is especially if they are new strings.
• use a click track to make sure you are tight

 

Every piece of equipment matters

 

Don’t spend lots of your hard earned money on microphones and guitar amps and then let the sound quality suffer by slacking in other areas:

 

• get some good quality instrument cables. Particularly if you are running them over significant lengths. This will minimize the chances of any unwanted noise interference creeping into your recordings. It will also reduce the chance of them breaking halfway through that perfect take!
• use a good quality audio interface (see my recommended gear section for my latest recommendations). This doesn’t have to cost you a lot of money, but it will make all the difference to the recorded sound. Make sure it has a low buffer size and low latency. There is nothing more infuriating than trying to record guitars with latency!
• bearing that in mind, make sure your computer or laptop is of a high enough spec. I wrote an article explaining what minimum specs you should look for here.
• try not to use too many pedals and effects in the signal chain. This will cause unwanted noise and will also make it trickier to record a tight sounding track. Keep it simple to start!

 

Double up tracks to ‘thicken’ the sound

 

Guitars, and in particular clean guitars, when recorded from your amp can sound quite weedy and thin in your mix. So you may wish to bring them out more.

Instead of fiddling with EQ settings or compression, a better solution is to record a second track. This tends to be easier for rhythm guitar parts where you can get away with not being as tight. For lead parts, it may take you a few more takes to nail it. Remember, you aren’t looking for an exact replica otherwise you would just copy and paste the first track. You want them pretty close so it still sounds tight but don’t get too obsessive.

Once you have done this, try panning one of the tracks to the left and the other to the right. You should notice a much fuller sounding guitar part that fills the mix.

 

Use the ‘white noise’ trick to overcome phasing issues

 

I mentioned earlier in the article that when you add more than one microphone when recording your guitar amp, you may come across phasing issues.

One way to get around this is the ‘white noise trick’. This involves sending a white noise track into your amplifier through the direct input, so your amp emits a white noise sound. This should be a more or less constant sound. Allowing you to move microphones around until phasing issues are minimized or eliminated:

1. Setup your first microphone in the usual way and then setup the second microphone in a position as close to where you think it should go.
2. Start playing the white noise. At this point make sure you have your headphones on because otherwise, you risk hurting your ears.
3. Start moving the second microphone around in a sweeping motion. You should hear the effect this has on the white noise in your headphones
4. Listen for the clearest white noise sound you can get, this is where the phasing effect is at a minimum.
5. If you find it hard to pinpoint the sweet spot. Try flipping the phase on one of the microphones and search for the spot where they cancel each other out the most, this can often be easier to find. Then once you find that spot simply switch the phase back.