Let's talk Iso Cabs

joeyowen

I'm thinking of building an Isolation cabinet, but on my research I came across people discussing a boxy sound, or bad sound from them.  I didn't want to be the newbie bumping a 3 yr old thread...

It would need to be pretty small, housing a 1x12 and an SM57.  How small could I make this, without is sounding crap.

Build isn't an issue, I think I know how best to build it. I'm more concerned with a small chamber giving a crap sound.  Any experience?

impmann

I had one that I sold to Sweepy. It was a home-made (not by me) job with a 1x10in speaker in it. I thought it sounded pretty decent, but it could get quite bassy, so you needed to roll more bass off than you would normally.

If it helps - this is the cab I had, explained by the chap who built it.

spacecadet

As far as I'm aware the boxyness comes from the cabinet being too small as well as not being treated properly. I've looked into this myself but never got round to actually building it. Ideally the bigger the box the better. If you are using a 112 cab, you would need to build the box big enough to fit at least a 412 and then some depth. The one I was going to build was like you going to house a 112. It was 3'x6' with lots of treatment. Sandbags on the floor to isolate vibrations and lots of auralex but not too much as to make it totally dead. You need some life. If you're going to the trouble of doing this I would also invest in a ribbon mic that you can mix in with the 57. You will be get far better results.

joeyowen

Waaiiiitt, sorry.  I didn't explain myself there

It will house a 12" speaker, not a 1x12 cab.  Not sure why I wrote it like that...

like this:

joeyowen

This might be better, robbed from TGP:

Danny1969

It won't be very quiet, wood isn't very good at stopping sound. Neither is the foam used for diffusion there 

For quiet you need a layer of mass - then decoupled then another layer of mass otherwise everything below about 200hz will just be audible outside the box

You could outperform those designs by putting the speaker in a crate and covering it with layers of loose carpet

joeyowen

Danny1969 said:

It won't be very quiet, wood isn't very good at stopping sound. Neither is the foam used for diffusion there 

For quiet you need a layer of mass - then decoupled then another layer of mass otherwise everything below about 200hz will just be audible outside the box

You could outperform those designs by putting the speaker in a crate and covering it with layers of loose carpet

tbh, I didn't think the images were particularly quiet, they lack the required box in a box idea. The idea of bouncing the waves however, gives me the impression it would sound better than a cab using 90 degree angles.  

I'm going to try and mock up some designs, and I'll post there here... but I have the artistic skill of a... insert something that can't draw anaolgy here...

ToneControl

joeyowen said:

I'm thinking of building an Isolation cabinet, but on my research I came across people discussing a boxy sound, or bad sound from them.  I didn't want to be the newbie bumping a 3 yr old thread...

It would need to be pretty small, housing a 1x12 and an SM57.  How small could I make this, without is sounding crap.

Build isn't an issue, I think I know how best to build it. I'm more concerned with a small chamber giving a crap sound.  Any experience?

I built one already. Pretty, and almost totally silent. No boxy sound I think
http://www.thefretboard.co.uk/discussion/comment/387817/#Comment_387817
This is an MDF box inside and oak box, with 3 drivers and 3 mics

I would sell for half what it cost me to build.

for something smaller, the best commercial one was the Hermit cab
I also have one to sell
http://www.soundonsound.com/sos/jun03/articles/hermitcab.asp

ecc83

Whatever you do put a power indicator (Maps do a 200W LED ladder) on the outside of the cab.

When you cannot hear the true level it is all too easy to blow a voice coil and if a valve amp, quickly followed by more expensive bits!

Dave.

joeyowen

ToneControl said:

joeyowen said:

I'm thinking of building an Isolation cabinet, but on my research I came across people discussing a boxy sound, or bad sound from them.  I didn't want to be the newbie bumping a 3 yr old thread...

It would need to be pretty small, housing a 1x12 and an SM57.  How small could I make this, without is sounding crap.

Build isn't an issue, I think I know how best to build it. I'm more concerned with a small chamber giving a crap sound.  Any experience?

I built one already. Pretty, and almost totally silent. No boxy sound I think
http://www.thefretboard.co.uk/discussion/comment/387817/#Comment_387817
This is an MDF box inside and oak box, with 3 drivers and 3 mics

I would sell for half what it cost me to build.

for something smaller, the best commercial one was the Hermit cab
I also have one to sell
http://www.soundonsound.com/sos/jun03/articles/hermitcab.asp

Quality work there bud! Well played.  Is that rockwoll lining between?  

I wanna have a good go at building one first, it is a hobby really but if it's total shite I may get back to you one day haha

I'm only after one speaker for now, the three would be over kill for me I think, I'm trying to be space efficient

joeyowen

ecc83 said:

Whatever you do put a power indicator (Maps do a 200W LED ladder) on the outside of the cab.

When you cannot hear the true level it is all too easy to blow a voice coil and if a valve amp, quickly followed by more expensive bits!

Dave.

hmmm tempting idea, but I'm never going to crank it massively, just to a good level for a 57 to pick up.  I will look into it though, good advice

ecc83

joeyowen said:

ecc83 said:

Whatever you do put a power indicator (Maps do a 200W LED ladder) on the outside of the cab.

When you cannot hear the true level it is all too easy to blow a voice coil and if a valve amp, quickly followed by more expensive bits!

Dave.

hmmm tempting idea, but I'm never going to crank it massively, just to a good level for a 57 to pick up.  I will look into it though, good advice

Ok but for those not so careful or have friends with HT-60s!    https://www.esr.co.uk/velleman/m4307c.htm

Maplin do a much simpler, cheaper version but I can't bloody find it!

Easy enough of course to use Rs and Cs and LEDs to make a two light jobbie but calibration is a problem for many.

Dave.

ToneControl

joeyowen said:

ToneControl said:

joeyowen said:

I'm thinking of building an Isolation cabinet, but on my research I came across people discussing a boxy sound, or bad sound from them.  I didn't want to be the newbie bumping a 3 yr old thread...

It would need to be pretty small, housing a 1x12 and an SM57.  How small could I make this, without is sounding crap.

Build isn't an issue, I think I know how best to build it. I'm more concerned with a small chamber giving a crap sound.  Any experience?

I built one already. Pretty, and almost totally silent. No boxy sound I think
http://www.thefretboard.co.uk/discussion/comment/387817/#Comment_387817
This is an MDF box inside and oak box, with 3 drivers and 3 mics

I would sell for half what it cost me to build.

for something smaller, the best commercial one was the Hermit cab
I also have one to sell
http://www.soundonsound.com/sos/jun03/articles/hermitcab.asp

Quality work there bud! Well played.  Is that rockwoll lining between?  

I wanna have a good go at building one first, it is a hobby really but if it's total shite I may get back to you one day haha

I'm only after one speaker for now, the three would be over kill for me I think, I'm trying to be space efficient

Hemp insulation

with more space, there is less chance of volume affecting the sound.

Cirrus

I think putting the baffle at an angle also reduces the internal resonance - which in a box that size will be in the low mids... literally a "boxy" sound and as already mentioned it's hard to do anything about those frequencies as they require mass to absorb  if you want to keep them in the box, or you let them escape at the expense of louder sound in the room.

ToneControl

remember the mic is only a small distance from  the driver, and will be louder than reflections, and if you use a no-baffdle approach, bass/mids are not reinforced anyway

ecc83

The box will be a resonant chamber  like a sealed box  loudspeaker and I am not sure foam is the best material to use as an absorbent of the standing waves. It is certainly in the wrong place.

Speaker "wadding need to be positioned at maximum air velocity (which by definition is zero at a wall!) . I would wrap the microphone(s) in a roll of BAF wadding and put a similar roll behind the speaker.

Not even sure angling the baffle will help much? It is non-parallel WALLS you need.

Oh! If only I still had dad's woodwork shop and infinite time and energy. Would that I still had Dad and his cabinet maker's skill!

Dave.