0-speakers in 67 minutes

[maxw]

Whipped these up quickly this morning







Quick?

[Mark25]

looks like your doing some quick cabinet volume comparisons on some monacor drivers to me.

[maxw]

Originally posted by Mark25
looks like your doing some quick cabinet volume comparisons on some monacor drivers to me.

Yep, I am trying to decide wether to have it ported or not. The bigger box is meant to be ported but I haven't got some plastic tube yet. The driver is a Response one from www.jaycar.co.nz

[noodle_snacks]

That looks like one of the jaycar carbon fibre drivers.. I am interested in which one it was, and what box volumes they are etc...

[maxw]

Originally posted by noodle_snacks
That looks like one of the jaycar carbon fibre drivers.. I am interested in which one it was, and what box volumes they are etc...

Its the 6.5" carbon fibre one, Specifications:

- Nom impedance: 4ohms
- Power handling: 80watts rms
- Freq range: 43Hz - 5500Hz
- Sensitivity: 89dB 1watt 1metre
- Voice Coil Resistance (Re): 3.79ohm
- Resonant frequency (fs): 43Hz
- Mechanical Q factor (Qms): 9.758
- Electrical Q factor (Qes):0.471
- Total Q factor (Qts): 0.449 ]
- Equivalent Volume (Vas): 15.1Lt
- Cone Area (square meter): 0.0133
- Mounting Depth: 75mm

and I have just made the 2 cabinets as suggested by jaycar:

Vented Box
- Box volume (litres)- 21 Lt
- Tuning Freq (Hz)- 44 Hz
- -3db Freq (Hz)- 40 Hz
- Two Vent Options
- Vent dia 50mm / Vent length 113.5mm
- Vent dia 66mm / Vent length 204mm
- Inside Cabinet Size: 225Wx282Dx350Hmm

Sealed Box
- Box Vol - 10.6 Lt
- Tuning Freq - 73.4Hz
- -3db Freq (Hz)- 74Hz
- Qtc - 0.707
- Inside Cabinet Dim: 175W x 220D x 277Hmm


I will report back with results. You'd think that since jaycar is throughout Australia and NZ it would be easier to find feedback on their speakers

[Mark25]

I'm doing a similar thing myself with some audax drivers, just for sealed (i don't want any resonances in my speaker enclosures that are not under direct control of the amp - like a port) though. my idea was to make one box of the larger size and fill it with bricks for tests on lower volumes, although this does mean for the smaller vol, i will have drifted from the "Golden-ratio internal dimensions for speaker enclosures". This does not bother me as i hope to not be using parallel sides and will concentrate on achieving a the lowest possible frontal area, which will take me away from the "golden-ratio" anyway.

[maxw]

Well I think they sound pretty good. They show how crap my car stereo must be because I can hear new things in familiar tracks.
I dont have much to compare them to though

The vented one, which is tuned to 44hz makes more deep bass than the sealed one - which I guess was predictable but there is a difference in the mid-range, not sure what. I think the vented one has more defined mid-range.

They are both quite different but I still cant decide what one is better

[Frazzled]

Just to point out it is EXTREMELY dangerous to store propane (LP Gas) in an enclosed space.

Propane is heavier than air so it tends to travel across floors and usually finds sources of ignition such as a furnace or water heater and the resulting explosion can be rather nasty.

Also, and potentially more dangerous is propane displaces oxygen so if you were to inhale some it can possibly displace the oxygen in your lungs and once it does you can breath all you want but the propane won't go anywhere so you suffocate, it is of course possible to hang upside down long enough for oxygen to displace the propane but by that time you are usually dead.

I say these things because I care about my fellow DIY'ers and I happened to notice the LP Gas tank tucked under the left hand side of your bench and depending on how full it is and the ambient temperature these tanks are designed to vent LP Gas or worse yet if some sort of accident in your shop should cause the valve or tank to rupture the subsequend burns from the LP Gas escaping could injure you just from contact (very cold).

So please even if this is apparently an empty container (LP Gas tanks are never empty unless they have never been filled) move it to a storage spot outside, the life you save may be your own.

OH and P.S. don't store LP Gas near where pets may frequent as the gas is more likely to kill them than you.

Thanks and sorry for the rant.

[Stocker]

Note: I had a 5lb bottle of Helium that looked exactly like that. So much so that the trash man wouldn't take it.

[Mark25]

Max,
it's not the same driver, but bear this thread in mind:

Audax on sale again...

Your car radio may not have the bass deffinition to make the effect mentioned in the thread noticable.
Mark