where does one go for help with 1/4 wave design ?

[zuki]

i don't know how to figure out the size box , but can easily build a box if have the dimensions

i built the ace box for the lowther driver

i recently found a car audio woofer and wondered if,could be used in a 1/4 wave application


http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=260013067242&ssPageName=STRK:MEWN:IT&ih=016


thank you

if someone would like to post a picture for me.

i can send them a latest picture of my fullrange speaker system to post on this forum

 

[Dumbass]

You can design an alpha-TL (cylindrical enclosure, one end open, one end closed) on a back-of-napkin basis if you have the article (dammit, I can't find the URL) and some basic T-S specs, and be fairly assured of good performance. And AFAIK such an enclosure isn't terribly sensitive to deviations from specs.

Once you start porting ("mass-loading") a TL, you can really screw it up unless you carefully model the enclosure using Martin's software (or other software of which I'm not aware). A well-designed enclosure of this type, however, will be able to reach lower.

 

[zuki]

i would like the speaker to have as much/go as low end as possible.

 

[Scottmoose]

Problem is, without any accurate T/S parameters, we're shooting in the dark here. If you can get hold of those, we're in business.

 

[Dumbass]

i would like the speaker to have as much/go as low end as possible.

Don't we all?

 

[XT8510]

see if you can find the T&S parameters of the Macrom I2.40 those are the exact same speakers. The TS for the Macroms were online at several European websites a few years ago.

I'll have a look if I can find them in the mean time.

My advice knowing these speakers do not waste time trying to get too much bass out of these. They work much better doing the mids and highs augmented with a bass unit or subwoofer

 

[zuki]

what size type enclosure would someone suggest ?

thank you


http://www.macrom.it/IMG/pdf/Manual-i240-5410.pdf

 

[zuki]

Specifications
The wide smooth frequency response, good sensitivity and high power handling make the
I 2.40 suitable for use in any quality installation
Power Handling: 80 Watts satellite (max. music)
50 Watts full range (max. music)
Nominal Impedance: 4 Ohm
Frequency Response: 80-25.000 Hz
Sensitivity (2.83V/1m): 89 dB
Unit Size ø -100 mm (4”)
Voice coil
Woofer ø - 54 mm (2 1/4”)
Tweeter ø - 28 mm (1 1/8”)
Resonant Frequency: 125 Hz
Dc Resistance: 3.40 Ohm
Voice Coil Inductance @ 1Khz 0.22 mH
Air Gap Height: 4 mm
X-Max Linear Excursion: ± 2 mm
Force Factor (BXL) 2.79 tm
Qms: 4.98
Qes: 1.26
Q/Ts: 1.00
VAS: 1.21 lt
Cms: 443 µM/N
Moving Mass (ms): 3.66 gr
Magnet System: Triple magnet
Cone Material: DPC
Dome Material: Soft Fabric
Nett Weight (per piece): 0.5 Kg

 

[Dumbass]

Happened to run across the alpha-TL article, here is a link:
http://homepage.mac.com/tlinespeakers/TLS/downloads/aTL-article.pdf

 

[zuki]

thank you

 

[Scottmoose]

Don't try tunig too low. About 90Hz will be the absolute limit, or the midbass will vanish. The Fs of these things at 125Hz is a bit high for a proper full-range application, so you'll need to cross over to some woofers. A single sub probably won't be a good idea either, as over about 75Hz, frequencies become directional, so you'll hear the LF coming from one point, and the rest from two different points.

If I were you, I'd try to get a couple of Manacor SPH-60X FR drivers shipped over from Europe. It'll be slightly more expensive, but they are superb-sounding drivers, very good value, and very well made. Although a more expensive initial outlay, they'll give you far more options to play with, and a much better ultimate sound.