Ideas for PC speaker project

[MPM]

This is what I've got to work with. The 3" drivers are Tang Band out of a logitech speaker. The specs are listed below. The 8" MCM speaker will go in a Tuba 18 horn sub. This is the second one I'm going to build. Works great with very little power. Can be seen on www.billfitzmaurice.com. The sub will obviously be on the floor with the 3" TB's on the desk. Any suggestion? I'm open for ideas.




Will be using the KG-3100 plate amp from Madisound. It simplifies everything for me. http://www.madisound.com/kgamps.html
This amp is used on the Subster/BB set available from http://www.rexspeakers.com/ The speakers look like TB products also.

TangBand W3-665SC

Diaphram Material: Paper
Surround Material: Santoprene
Nominal Impedance: 8
DCR impedance: 6
Sensitivite 1W/1m 88dB
Frequency Response: 120Hz-20KHz
Free Air Resonance: 120Hz
Voice Coil Diameter: 20mm
Air gap Height: 4mm
Rated Power Input: 15W
Maximum Power Input: 30W
Force Factor, BL: 3.2TM
Magnet Weight: 120g (4oz)
Moving Mass: 1.45g
Suspension Compliance: 1106 MN^-1
Effective Piston Area: .0032 M^2
X-max: 1mm
Vas: 1.6L
Qts: 0.63
Qms: 6.88
Qes: 0.69

[MPM]

How about a bipole using two speakers per box? Would eliminate the need for BSC. My desk sits on a wall. The amp has an adjustable crossover up to 150Hz.

Anyone? Bueller? Bueller?

[loninappleton]

Even though this is the full range forum, I'd like to hear how
the Tuba 18 shapes up. I have the cutouts for that but never
did the finishing panels mostly due to lack of tools and a cutter.

By cutouts I mean I routed the labyrinth for the panels but
never fitted the panels and the rest of the construction.


There's a favorite desktop design I have from the late Terry Cain called the Noogi.

http://www.audiosold.com/noogi.htm

You can find that at Cain and Cain. It's for a Fostex 3 in but I think the
concept holds up.

[AMV8]

MPM

You have put the thread in the full range forum so I guess you want full range type of responces.

Details of the 8" speaker would help a lot to determine the relative sensativities of the speakers and would help in trying to determine a cross over point. However even with information given it looks as though you you will probably have a loss of output in the upper base range/lower mid range and I would guess in the upper treble range. For a pc speaker this may be acceptable. You will have to listen to find out.

I would try and use the 3" speaker directly connected and without any filter and then put a first order filter on the 8" unit so that it "assists" the 3" as much as required in the base region to get the best sound. If you need help with a filter design ask me, or others, and I will give you a design for a first order filter as mentioned above.

I hope you enjoy the project.

Don

[MPM]

Originally posted by loninappleton
Even though this is the full range forum, I'd like to hear how
the Tuba 18 shapes up. I have the cutouts for that but never
did the finishing panels mostly due to lack of tools and a cutter.

By cutouts I mean I routed the labyrinth for the panels but
never fitted the panels and the rest of the construction.


There's a favorite desktop design I have from the late Terry Cain called the Noogi.

http://www.audiosold.com/noogi.htm

You can find that at Cain and Cain. It's for a Fostex 3 in but I think the
concept holds up.

The Tuba18 is very musical. I currently use my first born(haha) as my home theater sub. Doesn't go as low as it really needs to but it blows the socks off the cheapy HTiB thing I was using. Plans are to build a TT eventually with dual 8". I'm familiar with the Noogi. Asthetically pleasing to the eye but a little tall for my taste on my desktop.

Originally posted by AMV8
MPM

You have put the thread in the full range forum so I guess you want full range type of responces.

Details of the 8" speaker would help a lot to determine the relative sensativities of the speakers and would help in trying to determine a cross over point. However even with information given it looks as though you you will probably have a loss of output in the upper base range/lower mid range and I would guess in the upper treble range. For a pc speaker this may be acceptable. You will have to listen to find out.

I would try and use the 3" speaker directly connected and without any filter and then put a first order filter on the 8" unit so that it "assists" the 3" as much as required in the base region to get the best sound. If you need help with a filter design ask me, or others, and I will give you a design for a first order filter as mentioned above.

I hope you enjoy the project.

Don

I actually didn't want to post in the Loudspeaker section because I didn't want there typical responce. Would like to keep the speaker fairly simple but effective whether I use one or three drivers per box. I'm pretty much set on using the amps crossover for the simplicity of setup. This system doesn't have to have that special fullrange magic. Just good sound to replace my current aging PC setup. Shouldn't be hard to improve upon and the space savings on my desktop will be good for me also. I'm just limited on good ideas at this time so I'm still open for anything.

[loninappleton]

Also worth considering for the desktop and not tall for the
Tangband is The Brick.

I'd have to look that one up but it is a small box holding
a folded line.

Also in these projects, you avoid the thin wall of the
ready-mades even if they are bamboo. There may be interior treatments required to tune the design -- wait-- was this going to be an open back? I forgot.



I will look for the Brick.

[loninappleton]

http://www.diyaudio.com/forums/showthread/t-47558.html

Shows a picture of the completed design. There are sources for the
diagram as well.

For transport you could prob'ly make a loose pin hinge arrangement and carry them on a handle.

[MPM]

Thanks loninappleton. I've never seen the brick before. Has possibilities for me. I won't really need to transport them. If they go anywhere other than the computer will probably be my daughters room for her MP3 player and Playstation. With that in mind you probably understand my desire to use the Keiga 2.1 amp.

How about something like the Jazz? Would fit next to my desk very easy. For basic computer listening might work well. Interesting looking.

http://mastersourceaudio.nsmaudio.com/jazz.html

[loninappleton]

Originally posted by MPM
Thanks loninappleton. I've never seen the brick before. Has possibilities for me. I won't really need to transport them. If they go anywhere other than the computer will probably be my daughters room for her MP3 player and Playstation. With that in mind you probably understand my desire to use the Keiga 2.1 amp.

How about something like the Jazz? Would fit next to my desk very easy. For basic computer listening might work well. Interesting looking.

http://mastersourceaudio.nsmaudio.com/jazz.html

There has been some brief interest in deflector systems but you might find the ideal solution in PVC pipe. I've known 3 in. users who've put together a short PVC 'transmission line' and enjoyed the ability to
turn the elbows on the port to point it into the corners, out straight etc etc.

A number of PVC designs are at the transmission line forum.

I'll see if I can find the right page. Also the PVC's are fun for kids.

http://www.t-linespeakers.org/projec...son/index.html