Has anyone had success with a DIY isolation box?

Dave Stroud · Post by **Dave Stroud** » 9 Jan 2018 10:58 am

I live in an apartment, which makes isolation a necessity. I'm not looking for a truly professional alternative to miking a cab, but since I'm doing this project, I want to make it sound as good as possible.

I've scoured the internet for information on iso boxes. I have found that some people say they're terrible, some who say it worked great, and many who offered their speculation on what they think would and wouldn't work.

Unfortunately, many of the opinions I've found on iso boxes appear to be unfounded due to a lack of detail of exactly what they used and what they used it for. There's also many theories online that suggest different techniques for building an isolation box.

Some say it should be built with very little space, and others say there should be as much space in there as possible. There's also differing views on having parallel walls.

I imagine many of these people put cabs in their isolation box to crank their 100 watt amps up to 10. I wonder if their box would respond differently to their sound if they recorded at much lower volumes. That isn't an option for guitar players because they need to drive those tubes. I've got a Little Walter 59' being shipped to me, and I don't suspect I'll need to crank it up to extreme volumes to get a great tone. I wonder if an iso box does better with clean sounds at low to moderate volumes.

Here's what my current plans are, but I would love to hear any good or negative experiences you all have had with iso box.

I've ordered rockboard 60 for the main insulation, and light burlap to cover it (purely for aesthetics). I plan to have the cabinet facing up due to space constraints. This will allow about 18" of space in front of the speaker. I ordered a few "egg crate" acoustic panels- one to rest the cab on inside the iso box, and another to put between the iso box and the floor. I ordered some small "bass traps" which, when put together, should form two big "V's" on the wall that the speaker will face.

I plan to get a Sennheiser E906, and possibly pair it with an SM57. I will place them in front of the speaker using AmpClamp mic mounts.

For those interested, I'll have a Little Walter 112 cab (his larger version) with a PF-350 in there.

I'd love to hear the experiences some of you have had with isolation boxes.

Thanks!

Rick Campbell · Post by **Rick Campbell** » 9 Jan 2018 11:10 am

Have you considered recording direct?

RC

Dave Stroud · Post by **Dave Stroud** » 9 Jan 2018 11:25 am

I have a PreSonus audiobox that I could plug straight into... but I think just about anything else sounds better. There is a line-out on the LW head, but it can't be used without driving the speaker, so I would need to isolate the speaker anyways. Wouldn't miking the speaker in an isolation box would sound better than going direct though? Maybe even a combination of both...

Jack Stoner · Post by **Jack Stoner** » 9 Jan 2018 11:59 am

I can't vouch for how it sounds with steel, but there is a post on the Cakewalk Sonar forum about a new Digitech "CabDryVr" Cabinet simulator. Use it direct between the guitar (and effects) and the recording interface unit. I'm considering trying one myself as I like to record direct.

https://www.sweetwater.com/store/detail/CabDryVR

Bob Hoffnar · Post by **Bob Hoffnar** » 9 Jan 2018 9:29 pm

I've been using the Sarno V8 for recording direct and it sounds way better than it should.

If you enjoy building things an iso box might be cool. I use them in studios but they are usually at least as big as a closet. They can help but are rarely perfect.

Jack Stoner · Post by **Jack Stoner** » 10 Jan 2018 3:27 am

I tried a SG Black Box direct and didn't care for that although I like it playing in a band.

ajm · Post by **ajm** » 10 Jan 2018 9:40 am

To sum up what (I think) the O.P. is looking for: Silence first and foremost due to the apartment situation.

Jack Stoner's post on the Digitech pedal: Just to be clear, this is not meant to go between an amp and speaker. You don't need an amp at all to use this pedal.

One alternative is the way that I record........

Guitar, pedals, amp just like normal.
The output of the amp goes to a Palmer PDI-09 direct box.
Note: This particular DI box is designed to be placed between an amp and speaker. Not all DI boxes are, and are meant for low level instrument levels. Something to be aware of when shopping for a DI box.

Anyway.......Amp speaker output goes to Palmer DI box then to a power attenuator/load box (home made). Attenuator output feeds a speaker cabinet in a closet. The speaker is pretty much "isolated" and silenced by wrapping it in a couple of heavy moving blankets with bungee cords.
The amp can be turned up and then the attenuator is set as required. Shut the closet doors, and there is a teensy amount of noise in the room. So little that you can't hear it when playing an acoustic guitar in the room. (Truth be known, if you have the right attenuator/load box and have it set right, you probably don't need to even have a speaker hooked up. I always do, though.)

Now for the recording part...........
The Palmer DI has an XLR tap that feeds a preamp or EQ or whatever on it's way to your recorder.
This allows me to record a turned up amp virtually silently. I can use either monitors or headphones.

Does it sound as good as mic'ed amp? Probably not.
But a poorly mic'ed amp doesn't sound all that good either.
And mic'ing an amp correctly to get a good sound can be an art in itself.
Not to mention that an actual amp/speaker can get loud.

My set up is repeatable and quick.
The Palmer DI has three preset EQ/cabinet settings on it.
And the whole thing is virtually silent.

Dave Stroud · Post by **Dave Stroud** » 10 Jan 2018 11:28 pm

Well I've begun construction. This thing is heavy. I glued the pieces together too when I put the brackets on.

Jack Stoner · Post by **Jack Stoner** » 12 Jan 2018 8:38 am

I got to try the CabDryVr cabinet simulator. Forget it. First it cuts highs and the steel sounds "dead". I tried all the guitar speaker combinations and the bass speaker combinations and didn't really hear any speaker emulation that I would want to use for recording. Maybe with it cutting highs it skewered the speaker emulations.

My setup for testing was my Franklin with Lawrence 710 Pickups to a Hilton Volume Pedal to the CabDryVr unit to a Radial Pro D.I. to MOTU 896Mk3 Hybrid. I tried it with my JBL LSR308 studio monitors and with an Audio-Technica ATH-M50X headset.

Dave Stroud · Post by **Dave Stroud** » 12 Jan 2018 8:49 pm

I still have a bit to do, but I got alot done today. Did all the speaker box carpet, cut the insulation and covered it all in burlap, put casters on it, put the hinges on, and some other miscellaneous doo-dads.

Godfrey Arthur · Post by **Godfrey Arthur** » 13 Feb 2018 2:13 pm

You might want to try isolating the box from the floor so low end does not acoustically couple to the floor travelling throughout the structure in structure borne noise in case the casters end up transferring the sound to the floor. If your room floor is wood with air underneath, there's a good chance the vibrations will amplify compared to if the floor is cement.

You can use thick pieces of styrofoam planks about 4 inches thick to isolate the box from the floor.

If this box does not work then making a double walled version stuffed with fiberglass in the walls. It will get heavy as mass does help to slow down sound waves.

And then using dissimilar materials to confuse sound as sound waves are "intelligent" in that once they figure out the vibration frequency of a certain material, then they get through vs you used MDF for the outside, and then plasterboard or cement board on the inside. The foam will be good for high frequencies not for the lows.

The more sturdy the box, the sound captured inside will sound more relaxed instead of trying to blow the box apart where the sound is bouncing around acting on the speaker itself as well. Your metal braces might not last compared to screwed and glued 2x2's lining the corners, as the two screws are what's holding things together not the bracket itself.

YMMV.

Queensryche bassist used an iso cab with a speaker inside to add to his amp's sound in recording. They would drive the speaker in the box to distortion.

Here's an example of a double walled iso-cab.

The dead-air-space within the double walling is your friend.

Note the speaker baffle is ported to give the speaker a feeling of being in a larger box.

They used multi-ply birch for the interior wall and baffle.

Dave Stroud · Post by **Dave Stroud** » 13 Feb 2018 4:11 pm

Godfrey, kumusta dun sa Philippines??

I'm not sure if I mentioned it before, but I did put it on casters to separate it from the floor... But anyways, it may never get used after all since we've moved into a house and now have a dedicated room as the home studio. I'm in the process of acoustically treating it.

I might try to sell this thing on Craigslist. But it's heavy as heck and pretty big too!

Godfrey Arthur · Post by **Godfrey Arthur** » 13 Feb 2018 10:02 pm

Hey Dave, in the vernacular: ok naman dito sa Pilipinas. Naks! Thanks for asking!

Yes you've mentioned you'd put it on casters but sometimes those will transfer vibrations if the wheels are not the thicker rubber.

Good you've found a better place to do your music.

Sound proofing will still be double walling if you're going to do it right to be able to crank your gear at all hours of the day and night.

It won't be just your household, but YOUR NEIGHBORS with their speed dial set to 911.

Ventilation will be important and may be problematic if the ducting is connected to the rest of the house. Will be like megaphones in each room tied to your music room especially if the heater/aircon is on servicing the entire house.

I've seen bigger iso-boxes than yours that look like hot tubs.

You could also have a giant iso-closet to put your amp in if you're not wanting to soundproof an entire large room.

The modern project studio is a DAW with an iso-booth.

Have fun with your new studio!