These woofers were once used in the Voice of the Theater speakers. They were my first DIY speakers. I had the 16 ohm versions including the 511B horns and 802 drivers. I later built two more pair using the 8 ohm drivers for a neighbor to use with his band. I think I may still have a copy of the plans that includes other cabinets Altec made that used these woofers. I'll check.
The plans I have are from the 1968 manual listed on the site you referenced.
The copy I scanned of the Altec 861 is clearer than what is shown on the link you provided. See: http://woodartistry.com/external/Altec/Altec1.jpg
I think this design meets the requested specifications.
The actual, original box dimensions for the voice of the theater studio monitors was H 4Ft W 3Ft D 2.5 Ft according to my measuring tape...
You are close with your measurement estimates.
The drawing I posted is in response to the original request for a vented enclosure that could be used with the 416A woofer. This is not the VOTT drawings. The VOTT speakers are 42" x 30" x 24" but had two configurations. One was with the 511B horn on top (I made mine enclosing the top mounted horn, so they were taller). The other was with the speaker turned upside down and putting the horn in the port (with one panel removed to compensate for the space the horn displaces). For such a large bass reflex speaker, you would think the bass would be good. It was muddy, and the horns ring. Taping the horns did help some.
I next moved to making some JBL-S8 Studio Monitors that were much smaller and had much cleaner bass. These were the same drivers JBL used in the Paragon speaker system. With a passive radiator added, these were the Olympus and Sovereign speakers. (I still have these plans as well) I prefered the vented enclosure. JBL later made them available as a commercial speaker. I don't recall the model but a less expensive version that was close was the L-200. It used less expensive drivers but had the same cabinet.
i just saw this thread and i want to give an advice based on personal experience. A perfect enclosure for the Altec 416 is the Onken enclosure, which i've been using since 1984 and IMO has not been outdated.
The response is very flat and goes down to 40 hz easily. You can see a measurement i published in the REW forum one week or two under the name of Jean ( http://www.hometheatershack.com/foru...asurement.html) = look at the second graph, the first one is not well made. . It's a Japanese design and is very popular in France. The magazine "l'Audiophile" directed by Jean Hiraga introduced it and published plans. Here are a photo and the first article. If you have trouble reading french, i can help you, but the plan is clear enough, use 25mm good plywood. Big and heavy, but very subtle, not for a PA system.
Hi Jean, that is exactly what I'm looking for! Fantastic! But, I don't read French
Did you build the enclosures in the photo! Very Nice indeed!
Thank you for your contribution.
The cabs I built are not working for me. I just bought a pair of 416-8Bs I was thinking of another attempt with a different driver but now this plan appears... I will look for a matched pair of 416-8As and build these. Is there a chance you would have the X/O schematic for the system including the horn tweeter?