Straight 8 - the original Bottlehead speaker kit
- Thread starter Doc B
- Start date
I would purchase those parts from you if you ever find yourself across the border! I ran into my pair some years ago, and someone had hacked up the cabinets pretty badly to add some variety of ribbon tweeter or another.
The Straight 8 didn't use 10" sub drivers. Presumably those were intended for separate enclosures. The Superwhamodynes that preceded the S8s by a couple years used some inexpensive 10" drivers in bandpass subwoofer enclosures. Very, very different design. Regarding the substitution of ribbons for the original metal dome tweeters in the S8, I wouldn't necessarily have considered that a bad thing if the tweeters were good ones and the cabinets hadn't been hacked. One of my pairs of S8s had ribbon tweeters. Maybe Aurum Cantus G2si? Recall that I modded my cabs to fit them with a little careful router work. Another pair (my last, IIRC) had the selenium ST324, which may have been the best blend of all with those MCM 5 inchers.
You guys asking for links to 20+ year old projects do make me chuckle a bit. I can't even remember what I had for dinner last night, let alone where some of those ancient files might be. Some of that stuff may have gone by the wayside when we switched servers and rebuilt the site about 10 years ago. What's left can be found below - possibly with many dead links. At some point someone sent me copies of the original printed S8 cabinet plans, but I'm afraid I haven't a clue where they ended up. Kind of a moot point - pretty sure none of the drivers for these old designs are made anymore.
https://archives.bottlehead.com/community/index.html
You guys asking for links to 20+ year old projects do make me chuckle a bit. I can't even remember what I had for dinner last night, let alone where some of those ancient files might be. Some of that stuff may have gone by the wayside when we switched servers and rebuilt the site about 10 years ago. What's left can be found below - possibly with many dead links. At some point someone sent me copies of the original printed S8 cabinet plans, but I'm afraid I haven't a clue where they ended up. Kind of a moot point - pretty sure none of the drivers for these old designs are made anymore.
https://archives.bottlehead.com/community/index.html
I definitely wouldn't ship those, especially if you have the aluminum MCM woofers that Doc sprayed. If one gets damaged in shipping, a replacement can't be recoated. Feel free to drop me an e-mail at pb(at)bottlehead(dot)com and possibly we can figure out a time and place to meet closer to you.Ken said:
At some point Lord Adhesives stopped promoting that BL-100 stuff as a speaker cone and surround coating and started marketing it as a liquid (bodily fluid) resistant coating for bedsheets and gowns in hospitals. I can't even fathom how that sticky rubber stuff would feel sprayed on your hospital gown. Gross. Looks like they still make it. PJ talked them out of a pint or quart that I used for a couple years before it finally got too thick to use. I recall a gallon was very expensive and the shelf life was only 6 months.
https://www.lord.com/products-and-solutions/specialty-chemicals/aqualast-bl-100-butyl-elastomer-emulsion
https://www.adhesivesmag.com/articles/86502-butyl-emulsions-offer-new-options-adhesives-formulators
RE Superwhamodynes vs. Straight 8s - same tweeter, different 5" drivers. The Superwhamo drivers were very high Q and I put 4 of them them in a box with a big triangular "vent" hole. More or less an open baffle. They only went down to around 110Hz IIRC. They were not coated. The 10" woofers used in the Superwhamos were inexpensive and worked pretty well in a band pass box that went from 110 down to maybe 45Hz? Can't recall exactly. Should say in the archived article.
Not too long after I made those one of the new product guys at MCM and I had a talk and a while later they came out with a 5" driver with a different aluminum cone and a much bigger magnet that had a lower Q and a resonance around 55Hz IIRC. That is the 55-1870. That is what was used in the Straight 8s, in a vented box with real tubular vents and 8 of the drivers per side. Those S8 5" drivers and the tweeters were all coated on the front with thinned BL100 using an airbrush. The woofer frames were coated with a silica loaded latex paint for a while (very messy) and later they were damped with some super trick rubber backed aluminum tape that PJ suggested. I recall having to buy a $$$ case of that tape as the minimum order.
Being a big fan of the S8’s I have to post this link, it appears the drivers are still available:
https://www.newark.com/mcm-audio-select/55-1870/woofer-5-aluminium-cone/dp/39C2182
And I seem to recall the last version of the crossover eliminated the need for the coating on those drivers? I’m running mine with a ribbon tweeter and they still sound great!
https://www.newark.com/mcm-audio-select/55-1870/woofer-5-aluminium-cone/dp/39C2182
And I seem to recall the last version of the crossover eliminated the need for the coating on those drivers? I’m running mine with a ribbon tweeter and they still sound great!
