What You Need to Know about Guitar Isolation Cabinets

What You Need to Know About Guitar Isolation Cabinets

An isolation cabinet or “iso box”, is a speaker enclosed in a soundproof box.  I should also put “soundproof” in quotations because that isn’t always accurate.  My experience with isolation cabinets left me wanting a much better solution and I did eventually find it.  In my experience, guitar isolation cabinets aren’t all they are cracked up to be. Later in this article, I will discuss why I don’t use them anymore.

This article will cover all of the pros and cons of guitar isolation cabinets. I have used a few of them over the years for home recording and also for producing YouTube reviews.  I recorded approximately 100 videos using the Randall Isolation Box which we will discuss first.

How Conventional Isolation Cabinets Work

An isolation box will bypass your amplifier’s speaker. Instead of the onboard speaker being plugged in, you will run a cable out from the amplifier into the isolation cabinet. The speaker is enclosed in a custom made box designed to keep the noise down.

The Randall Isolation Cabinet

The Randall Isolation cabinet is great in theory but far from perfect.  This unit housed a 12″ Celestion Vintage 30 speaker and an internal mic clip for your favorite Shure SM57 or Rode NT3.

My main problem with the Randall isolation cabinet is its soundproofing. I also wasn’t a huge fan of the tone of it either but we’ll get to that later.  The “isolation” part of its name implies that there is some sort of noise canceling.

I used the Randall with my Fender Blues Deluxe Amplifier and Yorkville Traynor mostly.  I found out the expensive way that this unit is far from quiet.  There’s no way I’ve seen so far to attenuate a 12″ speaker down in volume.  The 12″ speaker caused nothing but noise issues for me anytime I got the amp up in volume.

Ambient Noise Issues and Cabinet Rattle

For those unfamiliar with Tube amplifiers, you need to turn them up to get the most out of them. What you would expect the Randall to do is allow you to use the amplifier at gig volume.  This is not the case. To be fair, the Randall guitar isolation cabinet did knock down the speaker volume but what you are left with is still a lot of noise.

The noise comes by way of a lot of cabinet rattle and low-frequency tones that made this unit unusable in my old apartment.  If I had the Blues Deluxe or Traynor down at 2 on the volume it was fine.  Any louder and these issues made using the unit impossible.  You are basically substituting one sort of noise for another.

I also tried a number of different speakers in the unit to try and enhance the tone but it didn’t help.  The recorded guitar parts always sounded boxy and lifeless and never as good as an amplifier in the room. Once you got the speaker pushing some wind the box would buzz uncontrollably and the handles would rattle excessively.

Custom Modifications Helped

I made many modifications to my Randall guitar isolation cabinet.  I started experimenting with some ways not only to make it sound better but to keep the issues mentioned above under control.

My first attempt to fix this was purchasing a lot of acoustic foam. I padded the inside of the cabinet under where the speaker sits as well as inside the top section.  This had an immediate effect on the overall external volume of the cabinet but didn’t improve the recorded sound.

Vintage 30 speakers aren’t my favorite in the World so I decided to try changing the speaker.  I installed a WGS ET65 and later an Eminence Swamp Thang and it still didn’t sound right. It sounded nicer, but still not quite right.

To get the side-handles to stop buzzing I literally put some foam under them and that worked well enough. After doing these modifications and setting my amplifier up differently to make it sound better with the cabinet, I was getting some decent results.  Did it end up sounding dead quiet or as good as the amplifier being mic’d up? No, not at all but it did the job.

It is HUGE

The Randall isolation cabinet is the size of a fridge without being quite as tall.  This is way too big and heavy to move it around easily.  For this reason alone if you are on limited floor space I don’t recommend it. If you live in an apartment or above ground floor do not buy this unit.

Randall Guitar Isolation Cabinet
Randall Guitar Isolation Cabinet

The AxeTrak Isolation Cabinet

The AxeTrak was my first isolated recording cabinet.  Looking back on my options at the time it was a decent unit but it suffered from a different set of issues from the Randall. For those unfamiliar with the AxeTrak, it is a soundproof box sporting a custom 6.5-inch speaker and built-in microphone.

Unlike the Randall isolation cabinet, the AxeTrak unit was something you couldn’t mod.  You were left with a “this is what you get” type situation that for me, didn’t stand the test of time.

The first thing I loved about the AxeTrak is the box is totally silent. You could have your favorite Marshall or Mesa-Boogie going into it late and night and someone in the next room won’t hear it.  The AxeTrak gets a huge thumbs up for being a true isolation box.  The isolation is easier thanks to the much smaller speaker.

The AxeTrack Downsides

A huge downside of the AxeTrak is its tone and “small sounding” recording.  The speaker has a horrible mid-frequency you can’t get rid of without a lot of post-production.  If your audio engineering skills aren’t good then stay right away from the AxeTrak.

Decent Results

You can get some decent results with this unit and it is a true silent recording cabinet but it’s far from perfect.  The tiny speaker yields very unimpressive results compared with my recommendations coming up.  There’s zero option to change the microphone internally as well so if you don’t like the dynamic microphone provided, you are out of luck.  Jeff from AxeTrak is a nice guy and I like his efforts with this unit and I would probably take this over the Randall if I had to do it all over again.


Unlike the Randall isolation cabinet, the AxeTrak is very portable.  Engineering wise, it’s a great unit but if you don’t want to spend time tweaking the EQ in the post then the AxeTrak isn’t for you.

AxeTrak Pro Isolation Cabinet for Guitar
AxeTrak Pro Isolation Cabinet for Guitar

Jet City Jet Stream Isolation Recording Cabinet

The Jet City Jet Stream Isolation cabinet is perhaps the most affordable iso box on the market.  This unit also houses a 12″ guitar speaker so as you may have guessed the cabinet is quite large. The physical build and design are very similar to the Randall Isolation cabinet.  The main difference though is the exterior has a nice blue and black Tolex versus the carpet shag of the Randall.

Jet City Isolation Box External Noise

The Jet City sounds like it attenuates the 12″ speaker a lot better than the Randall.  Testing this with a sound pressure level you can expect roughly 40 dB of sound reduction.  The Jet city also has far less cabinet rattle and low-end frequency boom over the Randall.  If you can find a Jet City Stream it’s a decent option for keeping the noise down, but it’s far from perfect.  The tonal results are very similar to the Randall iso cabinet too.  There’s a certain boxiness that’s hard to remove or get used to without using EQ in post-production.

The Rivera Silent Sister Guitar Isolation Cabinet

The Rivera Isolation Cabinet is a unit I have not tested.  After I posted videos online about the other units, everyone kept telling me the Rivera guitar isolation cabinet was the way to go.  I am certain that not everyone suggesting it had actually tried it. I didn’t want to buy into the hype and after my failed attempts with previous isolation cabinets, I needed to change my strategy.

The Rivera is huge! It’s not something I wanted to have in my studio and odds are it wouldn’t attenuate the noise that much better than the Jet City.  Something positive to point out about the Rivera Silent Sister is it does drop the audible volume of the speaker down about 30 dB.

The design internally is also a step up from the other units as it offers two microphone goosenecks you can place over the speaker cone.  Due to the internal cabinet design, this unit allows more airflow around the speaker.  This airflow is claimed to produce better tones than the other guitar isolation cabinets.

Rivera Silent Sister Guitar Isolation Cabinet
Check it out on Sweetwater

The Ultimate Silent Record Cabinet

The Two-Notes Torpedo Live changed my recording life.  This is by far a much better solution for home recording than any other isolation cabinet.  Space-wise, the Two notes torpedo has a very small 1 Rack Unit (1RU) footprint.  The Two-Notes Torpedo Live can be rack-mounted or simply placed on the desk which is how I use it.  The Two-Notes Torpedo Live has made all of the guitar isolation boxes redundant.

How the Two-Notes Torpedo Live Works

Much like the Randall Isolation Cabinet and AxeTrak, the Two-Notes is connected to your amplifier in exactly the same way.  This unit allows you to get all the best tone from your amplifier while bypassing the speaker entirely.

Impulse Response Technology Rather

Inside the Two-Notes Torpedo Live is built-in software that allows you to choose a speaker, microphone, and room.  Unlike a lot of digital modeling amplifiers and effects, the Two-Notes Torpedo uses impulse responses.

Impulse responses (or IRs) are accurate representations of speakers, amplifiers and more.  In the Two-Notes Torpedo live you get very accurate representations of the speaker you need.  Celestion and many other companies sell their own IRs allowing you to match the speaker you own.

The Benefit of the Two-Notes Torpedo Live

Having this unit saves the need for any loud guitar amplifiers.  From the back of the Two-Notes Torpedo is an output that will allow you to connect it to a mixer or sound card.  Two-Notes continue to update their Torpedo Remote software which is great.  Their most recent update allows you to use two virtual microphones inside the room.   One microphone can be used at the front and back or you can use two right in front of the speakers.

Two-Notes Torpedo Live - The Best Isolation Cabinet
Two-Notes Torpedo Live – Sweetwater

Two Years with the Two-Note Torpedo

I don’t miss the AxeTrak and I sure don’t miss the Randall guitar isolation cabinet either.  The Two-Notes sounds infinitely better than both of them.  It will give you very professional results while keeping the volume down to any level you like.  I have used this on hundreds of YouTube videos with many amplifiers including Marshall, Fender, Joyo, Vox, and more.

The Two Notes Torpedo Live is the ultimate silent recording cabinet.  It absolutely kills the physical speaker and microphone alternatives.  It sounds better, it’s smaller, it’s dead quiet, and it just works. I know the Two-Notes is more expensive than some of the guitar isolation cabinets you can buy, but it’s so much better.

If you still decide to buy an actual isolation cabinet over the Two-Notes Torpedo then check out my speaker buying guide.  Most cabinets are unloaded with no physical speaker.