Best cabinet for tannoy hpd 385

[THOMO]

What is the optimal box volume for the Tannoy HPD 385?

[lexi]

I'd round it at 200 litres? 300 ported are nice if you have space.

[speedysteve]

~230L GRF's

[BobC]

+1 on the GRF front.

[THOMO]

I am thinking of an oval shaped cabinet standing on its end made from laminated layers of bending ply.I have made a base for an oval dining table like this and it would look very cool as a speaker.
It would have 3mm veneer board laminated over the bending ply and be about 1100mm high by 580mm wide.
I am a bit concerned it might sound like a drum however.
Around 230 litres would be about right.

Not really keen on the GRF.I still have problems with sound waves coming out the horn 180 degrees out of phase .

[BobC]

A ported box will work just fine, bass will still be fairly low. Would recomend 7 layers of ply to give you 25mm (including glue). Use a 30 to 40 mm front baffle, 21 mm rear panel and brace the internals of the cab.

Line the internals with felt/wadding and if resonance is an issue use some anti resonance panels - or just glue some sheet rubber to the offending panel. Alternatively introduce a sheet of rubber into the laminating process, sandwich it between the layers of ply, this will act as a constrained layer damping system.

Will be interested to see how this one turns out.

[cooky1257]

180L ported tuned to 26 hz will give you ebs alignment that works well in a room.

[THOMO]

Do you know the port dimensions to suit 230 or 180 litre cabinets ?

[speedysteve]

Can agree that a proper front loaded horn is best but at a size ... Personally I've found the backloaded horn GRF bass to be preferable to the ported versions with big Tannoys DCs I've heard.
Perhaps it depends what you want to hear or listen for or find important in the presentation. If you can get that balance right for you then that is the ticket.

I am thinking of an oval shaped cabinet standing on its end made from laminated layers of bending ply.I have made a base for an oval dining table like this and it would look very cool as a speaker.
It would have 3mm veneer board laminated over the bending ply and be about 1100mm high by 580mm wide.
I am a bit concerned it might sound like a drum however.
Around 230 litres would be about right.

Not really keen on the GRF.I still have problems with sound waves coming out the horn 180 degrees out of phase .

[cooky1257]

Do you know the port dimensions to suit 230 or 180 litre cabinets ?

180L; 1 port@ 100mm dia x 120mm long.

[THOMO]

Thanks cooky.
That is quit a small port.
I will give it a try in an experimental box.

[cooky1257]

Hi Thomo,
You could also go for 2 100mm dia ports and tune to 32 hz with a length of 180mm.
Still ebs alignment the 32 hz tuning gives you a shallower shelf (about 3dB more output) down to 35 hz then falls away quicker than the 26hz tuning.

Hope this helps

Cooky

[THOMO]

Hi Thomo,
You could also go for 2 100mm dia ports and tune to 32 hz with a length of 180mm.
Still ebs alignment the 32 hz tuning gives you a shallower shelf (about 3dB more output) down to 35 hz then falls away quicker than the 26hz tuning.

Hope this helps



Cooky

Thanks again Cooky.That could suit my room better.