Ultimate Guide To Choosing The Best Mic Preamp For Your Home Studio

If you’ve been disappointed with the sound of your vocal or instrumental recordings, you may be missing a key piece of the recording studio puzzle: a dedicated microphone preamp.

A microphone preamp is an essential tool for getting professional-sounding recordings in your studio.  Paired with a high-quality microphone, your mic pre will let you capture vocals and instruments with greater clarity, detail, and dimension than before.

There’s a reason top recording studios spend the money needed for top-quality microphones and mic preamps: they deliver outstanding results that help create hit records and recordings that stand the test of time.

This guide will answer common questions on how mic preamps work, the types of preamps available, and how to choose a mic preamp that best fits your intended uses and, of course, your budget.

Let’s get started!

Check out my complete series of mic preamp articles:

• The Best Mic Preamps For Home Recording Studios (Under $300)
• Best Mic Preamps For Home & Pro Recording Studios (Under $500)
• Best Mic Preamps For Home & Pro Recording Studios (Under $1,000)
• Ultimate Mic Preamps For Recording Studios (Over $1,000)
• The Best 500 Series Mic Preamps for 2019
• The Best 500 Series Chassis/Rack/Lunchbox Enclosures for 2019

What Does A Mic Preamp Do?

A microphone preamp is simply an amplifier.  Microphones generate a very low-level signal that must be boosted to a line level signal that is usable by your audio interface or mixing console.

A mic preamp will boost that mic signal almost 400 times from its original level to get to line level.

Quality Counts

With this much amplification, it’s vital that the mic preamp is designed and built with quality components.

Poorly designed and cheaply made preamps will deliver thin-sounding, poor quality audio with high noise levels.

Now, these mic preamps in the average mixing console or audio interface are usually decent and completely usable…

BUT, in most cases, you won’t get the best sound from them.

Why?

Well, high-quality mic preamp design and components are expensive.

A manufacturer who designs and builds a $500 mixing console with eight mic preamps has to cut corners on quality.  They won’t use the best audio components – they really can’t if they want to make a product that also produces some profit for the company.

There is also the issue of space – there isn’t room inside a small $500 mixing console to include the best quality components and design for eight microphone preamp channels.

However, a $500 mic pre that only does one thing – mic preamplification – can incorporate better quality parts and superior design.  The sound quality will be much higher with a stand-alone unit.

Why Buy A Dedicated Mic Preamp?

If you want to get the most out of your studio, you’re going to need a dedicated mic preamp.

High-quality mic preamps not only create high-quality professional recordings but add very desirable character, clarity, depth, and dimension to your mic’s signal.

This is what you are really paying for in a quality mic pre.

For example, Neve, API, Focusrite, Universal Audio, and Avalon mic preamps are known for the excellent sound quality they add to a recording.

The richness and detail they add – with deep lows, smooth mids, and shimmering highs – and the character they bring to recordings have helped produce thousands of hit records that create emotional connections with listeners.

Even pro studios with million dollar recording consoles purchase a good half dozen dedicated top-quality microphone preamps.

The built-in mic preamps in these high-end consoles are excellent, but specialized mic preamps can bring additional colors, tones, and features that their console’s mic preamps don’t.

So, to sum it up, if you want to get pro sounding vocal and instrumental recordings, you’re going to need great mics and great mic preamps.

Mic Preamp Features:

Inputs:

Almost all mic preamps use standard XLR jacks to connect professional-level microphones.

If not, they’ll have a line-level ¼” input for connecting instruments like guitar or bass.   This input is frequently called a DI or direct input.

Instrument or DI jacks allow you to record directly into your DAW, which makes them very handy for modern track production if you want to access the mic pre’s tone or if you don’t want to mic an amp.

The input is usually a balanced TRS (tip-ring-sleeve) jack that provides better noise rejection from hum, radio, or RF interference than an unbalanced TS (tip-sleeve) jack.

On multi-channel mic preamps, you may also find a D-Sub connector that lets you connect multiple channels to your audio interface using a breakout cable or snake such as a D-Sub to XLR or D-Sub to ¼” snake.

Outputs

Almost all mic preamps use standard XLR jack for each mic pre channel output.  If not, you’ll find ¼” TRS jacks. Some mic pres have both for additional flexibility.

On multi-channel mic preamps, you may also find a D-Sub connector that lets you connect multiple channels to your audio interface using a breakout cable or snake.

Additional Features:

Phantom Power

All mic preamps (except the cheapest models) supply the 48-volt phantom power required by condenser mics and some newer ribbon mics.  Phantom power is provided through the mic’s XLR cable.

Built-In A/D Converter

Some mic preamps will include a built-in analog to digital (A/D) converter that allows you to connect directly to your recording device or DAW.

Stereo Link

Some mic preamps include a stereo link switch that lets you combine stereo-ready modules, or to set the gain with one knob across both channels.

Low-Cut Filter

Many mic preamps include a low-cut filter (also known as a high-pass switch) that lets you reduce low frequencies, usually below 150 Hz.  This helps eliminate low-end rumble, noise and microphone pops from making it onto your recorded tracks.

Types of Mic Preamps

The four basic types of mic preamps are:

• Tube
• Solid-state
• Hybrid
• Channel Strip

I’ll cover each of these preamp types in a moment…

Colored vs. Transparent Sound

Both tube and solid-state mic preamps have their own sound characteristics that are generally labeled as colored or transparent.

Mic preamps that color the sound are usually described as adding “warmth” to the recorded sound.    That coloration comes mainly from harmonic distortion or saturation of the signal that the mic preamp’s circuitry generates.

Most tube mic preamps color the sound, as tubes inherently produce harmonic distortion that is musical and pleasing to the ear.

The Avalon VT-737SP and Universal Audio Solo/610 are examples of popular tube mic preamps.

However, solid-state mic preamps also can color the sound, through both the preamp’s circuitry and their components, primarily the transformers.

The renowned solid-state Neve 1073 or API 512C mic preamps are desired for the signature sound they provide.

Transparent mic preamps do not color the sound at all.  They deliver clean, crisp and accurate sound.  They just transfer the microphone’s original sound to the recording in as pure a manner as possible.

The Great Transformer Debate

When considering mic preamps, the subject of transformers vs. transformerless designs always comes up.  It’s a topic hotly debated in audio circles among audiophiles.

In technical terms, transformers are used in audio circuits for a variety of applications, such as increasing or decreasing the signal voltage or impedance of a circuit.

In practical terms, transformers add color to the sound; users frequently liken it to a “warm vintage” sound.

Transformer-less designs create a more transparent and uncolored sound.

There are both high-quality transformer-based designs, like the Daking Mic Pre/EQ and Millennia M-2B, and transformer-less designs like the Grace M101 or Millennia HV-3C.

Most transformerless designs will be solid-state.

Good transformerless tube mic preamps are difficult to design and are very expensive, like the Massenburg GML8304 mic pre.

Transformer In/Out Switch

Some mic preamps allow you to switch the transformer in or out.  This lets you choose if you want to record with a colored sound or with a more clear and transparent sound.

The Warm Audio TB12 Tone Beast Microphone Preamp goes one step further.  It incorporates two different transformers.  You can switch between them to achieve different sounds.

Tube Mic Preamps

Tube mic preamps use one or more vacuum tubes to amplify the mic’s signal.

On many tube mic pres, you’ll see the telltale glow of the tube(s) when the unit is on, which looks kind of cool!

12XAX7 and 12AX7A tubes are very popular and are used in many mic preamps.

Tube Mic Preamp Pros:

Tube mic preamps are known for their warmth and musicality.  They produce a very warm, open, “fat” sound.

A tube’s characteristic sound is achieved by the way that it amplifies sound.  Unlike solid-state amplifiers which tend to be very clean, tubes distort the audio signal in a musically and aurally pleasing way.

Tube distortion emphasizes second-order harmonics that sound good to our ears.

Tube guitar amps are especially prized for the way they distort an electric guitar’s sound, resulting in fat, crunchy power chords and solos that sustain and sing beautifully.

Finally, tubes act as natural compressors and tend to even out note attacks by “soft clipping” them. The resulting smooth sound is prized and used on many vocal and instrumental recording sessions.

Tube Mic Preamp Cons:

Like most things, tubes eventually wear out and have to be replaced.

However, this is not a major consideration for two reasons:

First, tubes don’t wear out that often and can last many years, depending on use.

Second, most tube mic pres use one or two tubes, and the most commonly used 12AX7 tubes are only around $10 each.

Also, as tubes age, their sound can change, which can negatively impact the sound quality of the mic preamp.

As mentioned earlier, tubes slightly compress the attacks of notes.  Thus, a tube mic pre may not be the first choice for recording instruments that have sharp attacks, like snare drums, percussion instruments, or even acoustic guitar.

On the other hand… it could be the perfect choice if you are looking for a smooth “vintage” sound…

Tube Mic Preamp Specs

One final thing to know is that if you compare specs on tube vs. solid-state mic preamps, tube mic preamps fare poorly based purely on technical specs, with high harmonic distortion and noise floor levels.

BUT… the important thing to know is that it’s their inherent harmonic distortion that makes them sound good!   You can safely ignore these warnings, especially with higher-end models.

Popular Tube Mic Preamps

Here are some high-quality popular tube mic preamps:

• Avalon VT-737sp
• Universal Audio SOLO/610
• Art Tube Opto 8

Check out my reviews of the best tube mic preamps here.

Solid-State Mic Preamps

Solid-state mic preamps use transistors, not tubes, to amplify a mic’s signal.

The sound of a solid-state mic pre comes from its design, its amplifier components and circuitry (op-amps), and its transformers (if it is transformer-based).

Solid-State Mic Preamp Pros:

The benefits of solid-state preamps are:

• Clean, transparent sound
• Minimal distortion
• Ability to handle higher gain levels without distorting

Transistors provide a more consistent and efficient means of amplification than tube preamps, with less heat and distortion.

Solid-state mic preamps arguably capture more detail and a more “natural” sound than tubes.

As such, they are the preferred mic preamps for classical recording, especially for audiophile recordings.

Solid-State Mic Preamp Cons:

Lower-price solid-state mics preamps can be cheaply made and can sound harsh, grainy and noisy.

Top-quality solid-state mic pres that deliver a rich, full sound can be quite expensive, which is an issue for more budget-minded studio owners.

Popular Solid-State Mic Preamps

Popular high-quality solid-state mic preamps are:

• Neve Portico 5012
• Grace Design M101
• Black Lion Audio B173
• Focusrite ISA One

Hybrid Mic Preamps

Hybrid mic preamps are a combo of tube and solid-state designs.

The idea is to combine the best of both worlds; they are usually designed as solid-state mic preamps with a separate tube stage for warmth and color.

Typically, solid-state components drive the input stage, and a tube drives the output stage.

Popular Hybrid Mic Preamps

Some excellent popular hybrid mic preamps are:

• Universal Audio 710 Twin-Finity
• Summit Audio 2BA-221

Channel Strips

A channel strip is a microphone preamp combined with other signal processing circuitry all in the same enclosure.

The most common additions are EQ and compression/limiting, though other features like a de-esser or an aural exciter are sometimes included.

A channel strip is designed to provide everything you need to record, all in one convenient package.

As everything is in one enclosure, you get the benefit of a complete signal chain, less noise from connecting separate units, and ease of use.

And you save money by not having to purchase extra patching cables!

All in all, a channel strip can be a very versatile and affordable option for home recordists.

Popular Channel Strips

Some popular channel strips are:

• Universal Audio 4-710d
• Joemeek OneQ2

Single Channel and Multi-Channel Preamps

Microphone preamps are available in single-channel models, dual-channel models, four-channel models, and more, up to eight mic preamps in one enclosure.

However, one downside to be aware of is the more mic preamps a unit includes, the less quality each mic pre may have.

I’d be wary of multi-channel mic preamps under $200 or so – the quality usually isn’t there at that price point.

For most home studios, your best bet is to purchase a single or dual channel mic pre. That should take care of most recording session uses.

However, if you are looking to record drums, then a quality 8-channel preamp like the Focusrite OctoPre MkII Dynamic or the Audient ASP800 may be your best bet.

These 8-channel mic preamps are highly regarded for their excellent sound at an affordable price.

Mic Preamp Formats: Rackmount, Desktop, or Lunchbox

Mic preamps are available in three formats:

• Standalone desktop models
• Standard 19” rackmount
• 500 series “lunchbox” modules

Rackmount Units

Rackmount preamps are studio standards.

Many are single-space (1U) units, but some are double-space (2U) size.

Rack mounted gear certainly looks cool, and having your mic preamp racked also helps keep cables out of view for a cleaner looking studio.

One potential drawback is access to input and output connectors if your mic pre is rack mounted.  It can be difficult to access the rear connectors if the rear panel is not easily accessible or there are lots of cables blocking the connectors.

Desktop Models

Standalone desktop models have an advantage in that they are portable.  It can be placed close at hand with all the controls readily available to tweak during a recording session.

For one-man band studios this is very desirable; while playing or singing you can record while still having access to the mic pre’s settings.

500 Series Lunchbox Mic Pre Modules

A 500 series mic pre is a module built in the 500 series format commercialized by pro audio pioneer API.  The idea was that studio owners could create their own rack of modules – not only mic pres but EQs and compressors – customized to fit their needs.

Modules are placed in a 500 series enclosure, sometimes known as a rack, chassis, or portable lunchbox.

Enclosures usually have anywhere from two to 10 slots for modules.

The enclosure provides power and connectivity to all modules, plus 48V phantom power.

Note: Some enclosures have D-Sub connectors.  You will need breakout cables or a snake at an additional cost.  Be sure to check this before you purchase so there are no surprises!

The 500 series format is standardized, so any 500 series module can be used in a 500 series chassis.

500 Series Advantages

The first significant advantage is that 500 series mic preamps are quite a bit cheaper than their desktop or rackmount counterparts.   They are smaller and don’t have to include the power supply or connectivity functions that the enclosure provides.

This allows manufacturers to focus on adding only the high-value components needed for top quality sound in each module, making them very cost-effective and a great value for the price.

However, the initial upfront cost is higher, as you have to buy the enclosure AND the modules.

Some popular 500 series mic pre modules are:

• Chameleon Labs CL 581
• DBX 580 Mic Preamp
• Neve 1073LB

A few popular enclosures/ lunchboxes are:

• Radial SixPack 500 Series Chassis
• Lindell Audio 506 Power
• API 500-8B Lunchbox®

Which Mic Pre Should I Choose?

There are three essential factors to consider when selecting a mic pre for your studio:

• The sound you want
• Your future needs
• Your budget

The Sound You Want

Here are some general guidelines for achieving different tones:

• If the vocalist or instrument you record is thin sounding, a tube mic pre will help fatten up the sound.
• For instruments such as acoustic guitar, a tube mic pre can add warmth. But many engineers prefer to capture the instrument’s natural sound and opt for a solid-state preamp that does not color the sound
• Drums: a fatter sound is achieved with tube mic pres which compress the sound a bit. Solid-state mic pres bring out the attacks.
• Classical music recordings tend to use solid-state preamps for a pure, uncolored sound.

Your Future Needs

Always consider what your studio may require in the future. You may have a small studio now with only one microphone, but it’s likely that it will grow over time.

The most common “upgrade” is having two mic preamps so you can record instruments in stereo like acoustic guitar.

So, a dual channel model may be the best solution.

I started out with one mic pre.  Today I have three – one solid-state channel strip, a tube channel strip, and an inexpensive USB mic pre.

Don’t forget about going the 500 series module route.  Purchasing a 500 series enclosure and individual modules can let you choose a wide variety of mic pres for lots of flexibility.

Your Budget

Money, of course, plays a big part in what mic preamp you purchase.

I highly recommend getting a quality mic pre that you won’t outgrow soon.  Generally, you’ll be looking at mic preamps that start around $300 or so per channel.

Really inexpensive preamps under $100 will have issues with noise, gain, and overall sound quality.  It’s recommended to avoid those.

Final Thoughts

Choosing the right mic pre begins with understanding the various types and designs of mic preamps available.

From there it comes down to deciding the type of the sound that you want.  Whether you like a clear, transparent, pure tone or want to add some vintage warmth, there’s a mic pre that delivers it.

As always, quality will win out on quantity, so always try to buy the best mic pre you can afford.  You won’t regret it!

Check out my complete series of mic preamp articles:

• The Best Mic Preamps For Home Recording Studios (Under $300)
• Best Mic Preamps For Home & Pro Recording Studios (Under $500)
• Best Mic Preamps For Home & Pro Recording Studios (Under $1,000)
• Ultimate Mic Preamps For Recording Studios (Over $1,000)
• The Best 500 Series Mic Preamps for 2019
• The Best 500 Series Chassis/Rack/Lunchbox Enclosures for 2019