RS40-1044 8" Fullrange TQWT Design?

[hearing aid]

Need some help with construction on my first set of single driver speakers. As this is my first time around I wanted to keep cost and difficulty of construction to a minimum.

I picked up a pair of RadioShack 40-1044 8" full range drivers and began my search for a design. I went with the larger driver in attempts to salvage some fo low end that is lost with smaller drivers in a simple single folded pipe design. Unfortunately according to the generous leaflet included, the top end extension reaches only to about 18khz.(and this could be generous).

First off, does anyone know the T/S parameters of these speakers? I'd like to be able to calculate speaker dimensions but I have virtually no test equipment. Second, are there any other suggestions on a somewhat simple enclosure design that would be a good match? I have been leaning toward a simple folded voight or something similar. Third, does this whole thing seem like a good idea at all? Has any one else out there tried something similar with these drivers? the RS40-1044 is only rated at 89db and such a simple enclosure would probably not drastically affect efficiency.(they will be driven most likely with a 10-20w tube amp.)

Any suggestions would be appreciated. Thanks for helping the new guy.

cheers,
d

[kelticwizard]

Originally posted by hearing aid
...Unfortunately according to the generous leaflet included, the top end extension reaches only to about 18khz.(and this could be generous).

...First off, does anyone know the T/S parameters of these speakers?

ONLY to about 18 khz? I wonder what small percentage of the population can actually hear that high? Not too many people can hear over 15 khz.

If you can find an 8" speaker that goes up anywhere near that high smoothly, you have indeed discovered something special. And even if does go that high, the dispersion in the upper ranges would be very poor indeed. That is why that range is generally handled by a 1", (or smaller) speaker.

Let me do a little checking for the Thiele-Small parameters and get back to you. However, many people with no test equipment have said that Speaker Workshop by Audua, www.audua.com , makes checking the Thiele-Small parameters easy, if it has to come to that.

Looks like they just changed the address to www.speakerworkshop.com.

[kelticwizard]

I checked Radio Shack, the database of WinISD, and Google. I could find no Thiele Small parameters for the Radio Shack 40-1044. I cannot download Unibox because I don't have Excel. Perhaps somebody with Unibox can check their database. If not, you will have to measure.

[planet10]

Originally posted by hearing aid
First off, does anyone know the T/S parameters of these speakers? I'd like to be able to calculate speaker dimensions but I have virtually no test equipment. Second, are there any other suggestions on a somewhat simple enclosure design that would be a good match?

Parameters here at the Full Range Forum where the whole forum is dedicated to this kind of question.

I would suggest downloading Martin King's TL Software and run the driver thru and see what you come up with (note: TLs & Voigt Pipes are members of a family of speakers that use quarter wave resonance to extend the bass).

With only 89 dB effeciency, the speakers will be only 83-86 dB once you add some bafflestep compensation. You should perhaps consider getting another pair of drivers and build a bi-pole.

dave