Is there a plan so crazy it just might work? You better believe it.

Ok, so where are we at?

Previously, I posted about looking for ways to control the sound at our location. The concern from Pete (Sound Engineer), GC and others was that having amplified guitars would create uncontrollable spill and/or the room sound of having the guitar amps in the Bathroom wouldn't be so good.

Initially, I looked at Blankets, C-stands to hold them (film making equipment) and a few other options and then settled on trying to build Guitar Isolation boxes for the amps.

Taking a cue from Gearsluts and Mike Ralph, I looked into and and started trying to source the gear to build something..

I priced up Acoustic Foam and Chipboard/MDF and found it was going to be pretty expensive, maybe $400 a box.

Instead, I opted to re-purpose some old Server Rack Cases ($25 a pop) and go with Acoustic Insulation.

I did my calculations and based on the ebay specs, hired a Ute and went and got'em.

Screw Up #1 - always recheck and measure when you get there

No job is complete without a few errors, my first was not checking with the guy I was getting them from that they were as advertised.

They were shorter and narrower by only a few CM, but that was kind of important. Nonetheless, with some origami paper modelling and then double checking with an amp, we set to work building the first box.

Here's the bare box.

Fortunately for us our great mate Vicki went above and beyond with her jigsaw, to reduce the crates from a whopping 1.6m to a more manageable 1.1m.

Boy is she a handy Girl! She even drilled out a cable run in the base of the box so we can run leads and mike cables and power in there.

For Acoustic Insulation we chose Bradford Soundscreen, as it was affordable and available ($50 4.8 m2)

I got some great help from Martini Australia, manufacturers of Polymax - according to the Forums, its a better option, but I couldn't get it in time, but even though I was going to have to buy something else, they were really helpful in telling me to look for an insulation with a Hi NRC and Hi Density (1kg per square metre).

I decided we'd cover the batts with fabric and went in search of some. I tried some Hessian.

Screw Up -#2 - Check the insulation before buying the fabric covering.

The Bradford Soundscreen is Rockwool, which is great for this application, but turns into tiny fine particles when pressed. The hessian, which I got as it would allow sound to carry cleanly through to the insulation, was too loose to stop the particles. Very luckily, I was able to swap it for some denser felt.

So now with the box cut to size, the fabric and insulation to hand, we silicone sealed (caulked) the box.

The next step was to make the batts up into fabric covered panels. When working with Rockwool, or Fibreglass, you have to remember your safety gear - long sleeve shirts, gloves, mask and goggles..errr...oops.

We cut the batts into lengths, covered them in fabric and sealed them with double sided tape

Heh, these Masks are Trojans...heh...geddit? Trojan Protection? LOL

Finally, after assembling the two halves of the crate, lining them with bats, it was time to test with Mr Wizards amp.

Note - the Rockwool is not stiff enough to self support - I used some Gaffer Tape for the the test but will have to find a way of securing the batt to the box - but I wont glue it at this poitn as I might need to remove the batts, so I'll probably go Velcro.

We're not looking for 100% sound enclosure, we just need to drop the levels to reduce spill and to be able to control reflections.

This setup will have the amp in one half  of the crate and the mike on the other side, then wedged together with a small gap to allow some air ventilation - yes I know that means some excess spill, but we knew that going in.

If we had been able to get the Polymax stuff, we would have had a denser insulation, but even so, the result was terrific. We tested Mr Wizards amp cranked right up and the spill was acceptable.

If we changed the position of the amp and closed the box we'd drop even more noise, but we're concerned about the heat of the Valves inside all that insulation.

 Now all we have to do is build another one for Rosie. OMG - this single one was probably about 10 man hours work and I need this by Sunday. Yikes!

When we do the recording test with the mike inside, I'll post a vid.