My latest little project

[bagman67]

Nifty!  Is this for PA/sound reinforcement, or is this for your AxeFX, or studio monitor, or...?  Maybe something to make your old Styx 8-tracks sound a little sharper?

 

[rgand]

Beautiful! :icon_thumright:

 

[Logrinn]

So the insides are made to act as some kind of diffusers? Or absorber of sorts.
Mainly on higher frequencies, yes?

 

[mayfly]

Sorry about the delay!

To answer everyone's questions, they are Hi End HiFi speakers.  For the stereo don't-cha-know.  The diffusers are of the skyline type as described in the classic BBC paper on the subject - I'll post a link when I find it again.  They are tuned to diffuse the lower mid-range but leave the bass alone.  That is, they diffuse everything that the woofer puts out up until the crossover point where the tweeter takes over.  Bass is intentionally left alone so that the port works.

Oh - and the speakers are coaxial: the tweeter is in the middle.

They test really really well and sound superb!  Better than my Linkwitz Plutos!

In other news, the amps are alive.  Here's a photo of the action.

Yes, I made two pairs - one pair is destined for the far east.

 

[Cagey]

Interesting design. Any idea what they weigh? Not that it makes a whole lotta difference for home entertainment speakers, I'm just curious.

 

[rgand]

Those look great! They seem like a good design. They must be solid with all the material in them. I'll bet those don't vibrate across the floor.

 

[mayfly]

Interesting design. Any idea what they weigh? Not that it makes a whole lotta difference for home entertainment speakers, I'm just curious.

It's not bad - about 15 kilos

 

[Cagey]

Is that all? I would have expected much more.

 

[mayfly]

A lot of wood gets removed from the center!  So much so that I made a couple of speaker stands out of some inner bits... and they are heavier than the speakers!

 

[Cagey]

It's great when scrap wood turns into something useful.

 

[zebra]

Yes, I made two pairs - one pair is destined for the far east.

Nova Scotia?  :icon_scratch:

 

[mayfly]

Yes, I made two pairs - one pair is destined for the far east.

Nova Scotia?  :icon_scratch:

No, not New Scotland.  Closer to New South Wales 

 

[mayfly]

Prototype enclosures for the prototype 100W monoblocks:

 

[new-killer-star]

based on this paper or a different one?

http://downloads.bbc.co.uk/rd/pubs/reports/1995-01.pdf

MODULAR ACOUSTIC DIFFUSER:
The development and performance of a modular acoustic diffuser

 

[DarkPenguin]

So are the monoblocks your design or a kit or based on something?

 

[ByteFrenzy]

Looks strange somehow. I'd want the cooling fins projecting from the housing, like they are now I think you'll be restricting airflow.

 

[Cagey]

At least they're external. If they stuck out any more, they'd be in harm's way.

 

[mayfly]

So are the monoblocks your design or a kit or based on something?

Glad you asked!  They are my own design.  I'll post the schematic and PCB layout when I have a chance.

 

[mayfly]

At least they're external. If they stuck out any more, they'd be in harm's way.

yea that's the intent.  The plan is to put them under the speakers.  Lisa does not like stubbing her toes on stuff.

 

[mayfly]

based on this paper or a different one?

http://downloads.bbc.co.uk/rd/pubs/reports/1995-01.pdf

MODULAR ACOUSTIC DIFFUSER:
The development and performance of a modular acoustic diffuser

That's cool - hadn't seen that one.  The one I used had more of the underlying maths in it.