Utah B8JC-W...datasheet, please !

[aldovan]

Friends

I need informations about the Utah model B8JC-W.
Anyone can help me ?

Thanks,

Aldovan

[tomtt]

what djk said on the speaker asylum .





might try these with a flat baffle ...

[AstroSonic]

Found a listing for an 8JCW in the 1970 Allied catalog. Limited data: 8 ohms, 10 oz. ceramic magnet, dual cone, $5.49. This model is probably a few years older than the 'B' model you have. It was a 'low cost, extended range' speaker generally used for Pa speakers. there was a hifi version with a cloth accordian surround (CS8JCW: $8.90). These drivers predate T/S parameters and design methods. A data sheet would not have the information needed to design an enclosure for them, although it might include a recommended enclosure design.

The qts and Fs are likely to fairly high, making these best suited to open baffle use, with a woofer/sub assist. This is most easily done with a sub having a plate amp with controls for xover frequency and volume.

Give them a listen in whatever boxes you have or on 2 x 3 ft boards. They will likely need a fair amount of breakin (a few to several 10's of hours). After the sound quality has stabilized, find someone to measure the T/S parameters so that an optimum enclosure can be designed.

These are broadly similar to the EV MC-8. These take nearly 150 hours to breakin, but are remarkably neutral and non-peaky. Well worth the time and effort. Prior to breakin they were very colored. Just suggesting that you give them a chance...

Good luck,

Bob

[GM]

Greets!

I remember these, still got some specs in BoxPlot with diam., Xmax estimated and sens. calculated IIRC, but this was measuring used drivers long ago, so probably not worth much more than a guideline to drivers this old now.

GM