Rob wrote:
I'm thinking of adding a subwoofer to my main speakers (Dynaudio 52s),
and I'd like to have a go at building one. Bit of background info:

Room is about 16' x 12' -
http://www.ifyoucan.org.uk/music/pics/musicroom.jpg
I don't want massive bass, just something to fill the missing bottom
bit, and an intro to DIY audio.

I can pay say 500UKP, but prefer less.

I like the look of
http://www.iplacoustics.co.uk/ipl_sw..._subwoofer.htm

I had a cheapish REL for a while, but found it rather 'one note'.

My woodworking skills are pretty basic, but I seem to pick things up by
doing. I fancy this as a primer for some Keith G-type horns - a taster
to see if I can screw 6 bits of wood together :-)

Any recommendations welcome.

Rob

I have played around with subs a fair bit.
Most are good with movies and techno music but not much else.
The one note thing is common.
In my experience the only way of getting bass extension without losing
speed, timing and texture is to use a high sensitivity 15 inch pro type
woofer in an appropriate sized box.
The standard subwoofer uses a heavy rubber surround,thick cone and lots
of excursion which has to make for a slow and smeared sound.Pro drivers
use cloth surrounds,light paper cones and short cone excursion and so
have much better speed and transient response[high sensitivity also
helps here.
I have made fantastic sounding subs using the RCF L15/554K 15 inch
woofer.These are suberb quality Italian speakers and I understand back
in production.Not cheap but still good value.
I have found they work best in a 100 litre box made into a coffee
table,downfiring with 100 mm feet for a gap and positioned between the
speakers and listening position.Any decent sub amp with inbuilt EQ
boost around 35hz[standard] will drive these well and power is not
really an issue because they are 100db/watt sensitivity.They don't go
ultra low[Fs is 33hz] but seem to breathe and integrate well with most
speakers-but really good with electrostats.
You might also want to try a high pass filter on your
Dynaudios[capicitor] to roll off their bass below 70 hz.This often
helps subwoofer integration .You can also try plugging the speaker
ports if they have them.

JT

wrote:
Rob wrote:
I'm thinking of adding a subwoofer to my main speakers (Dynaudio 52s),
and I'd like to have a go at building one. Bit of background info:

Room is about 16' x 12' -
http://www.ifyoucan.org.uk/music/pics/musicroom.jpg
I don't want massive bass, just something to fill the missing bottom
bit, and an intro to DIY audio.

I can pay say 500UKP, but prefer less.

I like the look of
http://www.iplacoustics.co.uk/ipl_sw..._subwoofer.htm

I had a cheapish REL for a while, but found it rather 'one note'.

My woodworking skills are pretty basic, but I seem to pick things up by
doing. I fancy this as a primer for some Keith G-type horns - a taster
to see if I can screw 6 bits of wood together :-)

Any recommendations welcome.

Rob

I have played around with subs a fair bit.
Most are good with movies and techno music but not much else.
The one note thing is common.
In my experience the only way of getting bass extension without losing
speed, timing and texture is to use a high sensitivity 15 inch pro type
woofer in an appropriate sized box.
The standard subwoofer uses a heavy rubber surround,thick cone and lots
of excursion which has to make for a slow and smeared sound.Pro drivers
use cloth surrounds,light paper cones and short cone excursion and so
have much better speed and transient response[high sensitivity also
helps here.
I have made fantastic sounding subs using the RCF L15/554K 15 inch
woofer.These are suberb quality Italian speakers and I understand back
in production.Not cheap but still good value.
I have found they work best in a 100 litre box made into a coffee
table,downfiring with 100 mm feet for a gap and positioned between the
speakers and listening position.Any decent sub amp with inbuilt EQ
boost around 35hz[standard] will drive these well and power is not
really an issue because they are 100db/watt sensitivity.They don't go
ultra low[Fs is 33hz] but seem to breathe and integrate well with most
speakers-but really good with electrostats.
You might also want to try a high pass filter on your
Dynaudios[capicitor] to roll off their bass below 70 hz.This often
helps subwoofer integration .You can also try plugging the speaker
ports if they have them.

JT


Many thanks JT - the RCFs are available he

http://www.allangordon.co.uk/Drivers...rive-Units.htm

Do you have any hints on cabinet design/amplifier? 100L strikes me as
quite large?

I've had a look around since posting and it seems there's quite a
following of DIY subs out the

http://www.design3dw3.co.uk/audio/audio-kit.htm

Using the Shiva and their amp seems a possible alternative choice. The
issue for me is finding the right things for my taste/existing
equipment/room/abilities - hence the IPL as a reasonably thought through
first try.

Rob