421-8h series II

[FPN]

I have a circa 1978 421-8h series II in excellent condition which I have been using as a monitor in a minimum size enclosure. Since I'm a bass player I'd like to transfer it to a larger enclosure (but small enough to transport in a compact station wagon). I'll use it by itself or ocassionally with another bass cabinet I own for large gigs. My questions- Is it worth buying a cabinet without a speaker so that I can use the Altec as opposed to new cabinets rated at 300 or 400 watts RMS. If so what style enclosure (bass reflex etc.). What size box and port ?. Acoustic fiberglass batting?. Are the Thiel-Small parameters really critical for a decent bassy and loud sound? Any commercially available cabinets which would fit the bill?. Any advise is appreciated.

[AllanCT]

Nice speaker. I have a pair that came in my A7 cabinets.

Anyway I believe you might want to find an Altec 1204B cabinet empty. That is a floor standing although kind of large box for the woofer and the horn speaker.

If you could get dimensions of the woofer part of the overall box the speaker should sound fine in that type of ported cabinet.

Overall dimensions of a 1204B are 45 x 28 x 28. Big box.

I would use the Altec in a new box, or an old Altec one for sure as opposed to something new.

[rolandr]

Allan although I am a guitar player I was forced
to play bass in a band for a few years therefore I can relate to your situation. We are always looking for that magical small light cabinet with prodigeous deep bass output. Unfortunately it does not exist. At best it is always a compromise.
As you know the Fender bass only reaches to about 32Hz in freq so in reality you don't need lower response. On the contrary deeper bass just rattles the stage and mudddies the sound of the band. That is why Ampeg in the 60's designed the 8-10" cabinet which is now widely copied as the 4-10" often stacked. What you want is thumping bass around 70Hz and up. It carries much better. Therefore shoot for a vented reflex cabinet tuned to about 60-70Hz the lowest. Use full fiberglass stuffing and reduce T/S volume recommendations by 20%. I would use pine as it is rigid and light or plywood not MDF. Definitely use a solid state amp.

[Rex Mills]

I used a simple 3.5 cu. ft. sealed enclosure for many years and was satisfied with the results. 3/4 " plywood with some 2X4 bracing, lined with 1" fiberglass. Very portable, easily carried by one person and will fit in a wagon. Tight punchy sound and decent bottom. Think Phil Lesh!

[Fitts]

If you bolt two woofers face to face and wire them out of phase to each other (when one pushes the other pulls) you create a compund unit that acoustically requires an enclosure half the volume of what is required for a single woofer. The push pull motion of the voice coils also improves other dynamic aspects of the pair when compared to a single driver.

Doing this would enable you to have a small box with good low frequency capabilities and a lot of power handling capacity. It sure is going to look weird on stage but will that really matter?

Just a suggestion that requires you to find another 421. Best Wishes