Isolation cabinet design for Blackstar HT-112

[Battie]

I thought I’d share my drawings of an isolation cabinet designed specifically for the Blackstar HT-112 speaker cab. I won’t be building it until Jan/Feb next year so i can’t test and post results until then. However, I made a very similar iso cab (just a bit bigger) about 5 years ago from similar materials which worked well, so hopefully this will too.





Some small details are missing from the drawings. For example, four steel corner braces on the base corners, latches for the lid to stop any chance of it vibrating or rattling and screw-in rubber feet. I did’t have the patience to draw the surface of the 25mm acoustic foam either. The surface of the 80mm foam took me long enough.

Some notes on construction
As i mentioned, I’ve made one of these before. I think the ply could actually go as thin as 10mm. My last Iso box was 12mm. I’ll make that decision when I come to it. PVA glue and flat-head wood screws actually provide a pretty solid construction but I use four metal corner braces for extra stability. Some sound will escape through the gap cut for the speaker cable and mic cable but this is minimal. The Blackstar doesn’t have to be played that loud to sound great anyway. The inner plywood base merely functions as a flat surface to keep the mic stand and speaker cab level. It also helps keep the box solid as the edges are glued/screwed into all four sides of the box. I’m sure some sound reflects off the floor, but from memory, it didn’t effect the sound negatively. I might experiment with laying a square of 25mm foam in front of the speaker cab with a hole cut for the mic stand.

Notes on the speaker cab
The Blackstar HT-112 is an open back cabinet. The dimensions are: W443mm x D249mm x H444mm. It should fit pretty snug into the iso cab… if I’ve measured correctly.

Comments/suggestions/criticisms are more than welcome. If for some crazy reason you'd like to try and build this yourself, just remember to double check measurements as I haven’t built this myself yet.

Materials/dimensions
Initial cost estimates on materials come to just under €60. Might cost a bit more if i get the ply cut to spec.

15mm plywood Could possibly go as thin as 10mm
External base - 604mm x 1000mm
Top lid - 604mm x 1000mm
Internal base - 574 x 970mm
Sides (x2) - 564mm x 1000m
Ends (x2) - 564mm x 574mm

40mm isolation board
Base - 574mm x 970mm
Ends (x2) - 494mm x 509mm
Sides (x2) - 509mm x 970mm
Top lid - 494mm x 890mm

25mm acoustic foam
Sides (x2) - 469mm x 890mm
End - 469mm x 444mm
Top lid - 785mm x 444mm

80mm acoustic foam
End - 469mm x 444mm

I’ve designed an iso box for the Fender 112 enclosure and can post it here if anyone is interested. The Fender Super Champ X2 HD was another option and in the end I’ve decided on the Blackstar.

 

[wavewarrior]

Like the idea, may try building too.
Used to build ATA cases, might be cool to design one on casters for more storage options too.
I like it, thanks!

 

[fuzzsniffvoyage]

I thought about building an iso cab. started pricing and found I could just buy this:

Randall Isolation 12 Speaker Cab | Musician's Friend

I've had it for a while, I like it a lot. I did make a few additions, like a speaker grill and an adjustable goose-neck mic clamp, so I can put 2 mic's in there. I just let the other cable hang out of the top and don't shut it all the way. I should really drill a hole in the thing and do it up right.

 

[Battie]

Yeah, these are a good option, but all things considered, building my own is a better option for me. Materials work out a lot cheaper, at least where I am, and I don't mind the work involved in building it.

Casters are definitely a good upgrade.

Cheers.

 

[minerman]

I built my own ISO cab, & it does work pretty good...I first just built a box big enough to put either of my 1x12's in, with plenty of room for mic adjustment & a shitload of Roxul Safe-N-Sound...Worked really good actually, but I ended up building an inner box too, with wingnuts holding the speaker (which I can change in just a couple of minutes), & it made it even quieter....

Here's a pic of how big my ISO cab is compared to my desk/guitar:


And here's a pic of the inner box while I was building it:


While I use low-watt amps with my cab (Marshall DSL-1 H & Egnater Tweaker 15w H), it still kills the noise enough so I can play/record at 3-4 a.m. without disturbing the wife, which was the whole point of building it....

It may look like shit compared to the commercial ISO cabs, but just guessing, I've got about half as much in the materials I used to build this than one of the Randall ISO's cost, not counting the speakers...

While I still use my ampsims, it's really nice to have real amp tones anytime I want, & at pretty much silent noise levels....Of course, if I used a bigger/higher wattage amp, it wouldn't be as quiet (the Tweaker is actually loud as hell for 15w), but with the amps I currently have, it works really well.....

 

[wavewarrior]

I built my own ISO cab, & it does work pretty good...I first just built a box big enough to put either of my 1x12's in, with plenty of room for mic adjustment & a shitload of Roxul Safe-N-Sound...Worked really good actually, but I ended up building an inner box too, with wingnuts holding the speaker (which I can change in just a couple of minutes), & it made it even quieter....

Here's a pic of how big my ISO cab is compared to my desk/guitar:


And here's a pic of the inner box while I was building it:


While I use low-watt amps with my cab (Marshall DSL-1 H & Egnater Tweaker 15w H), it still kills the noise enough so I can play/record at 3-4 a.m. without disturbing the wife, which was the whole point of building it....

It may look like shit compared to the commercial ISO cabs, but just guessing, I've got about half as much in the materials I used to build this than one of the Randall ISO's cost, not counting the speakers...

While I still use my ampsims, it's really nice to have real amp tones anytime I want, & at pretty much silent noise levels....Of course, if I used a bigger/higher wattage amp, it wouldn't be as quiet (the Tweaker is actually loud as hell for 15w), but with the amps I currently have, it works really well.....

Another nice idea!

My Marshall JVM1 is pretty close to your DSL1 in tone, what speaker are you using?
Thinking a Vintage 30 might sound pretty good.

Is that 3/4 plywood & 2"x4" construction?

Thanks