Sunn 12" Speaker Power Capacity?

[Ugh]

I have a Beta Lead 212 combo that I'd like to rob the speakers from. I'm using the head section through another cab and it sounds great, but I don't really like the combo itself. I think that the small cab size has something to do with it. I have an empty 412 that I'd like to mount the two Sunn 12s in. I assume that they're 8 ohms each, as I get a 4 ohm reading off of both. They have large square magnets and no readily visible markings.

Any idea of how much wattage they can handle?

Also, any idea where I might get a beta series head shell? I posted in the classifieds section to no avail...

[stanner]

sorry don't know the answer-i have a sunn cab 2X15 w/ similar spkrs-square backs w/ no visible markings-loud as hell. tried to selll it once but i couldn't tell the buyer what spkrs they were. think they are originals tho...someone here knows somethin' right?

[EdBass]

I'm pretty sure they are CTS, maybe early Eminence. Those 12 and 15 inch square magnet CTS and Eminence drivers were in all kinds of cabinets, combos, organs, hi-fi sets, etc. in the late 60's and 70's.
I have a pile of them that I've pulled over the years when upgrading cabs to premium drivers; which is not to say that they sound bad, in fact the 15" version is OEM in the Ampeg B15N which arguably may be the best sounding bass amp of all time.
Probably without doubt the most recorded bass amp of all time anyway.

Don't know the actual watts rating of your drivers though. CTS (and Eminence) pretty much built those unmarked drivers to spec for the application, so although they appear to all be identical they often have varied tonal qualities and power ratings depending on who they were designed for and what product they were for.
My guess would be about 30 watts apiece, but considering they were OEM in a 100 watt amp they may be rated for 50 watts or more; trading off better sensitivity for increased power handling.

Even though they are "generic", they have/had a speaker code ink stamped somewhere on them, at least they did when they left Kentucky. It may be worn or aged off of them, but check in odd places for it. That will at least tell when they were made and by who.

Anyway, ratings schmatings; use your ears to tell when they are begging for mercy. You can hear a speaker being over powered. Chuffing, farting, popping, etc. are signs that the cones are bouncing out of their voicecoil gaps, and while many times (particularly with guitar) the drivers will easily take twice their "rating", other times a 50 watt amp can disembowel speakers rated for twice that.
The ears will tell you what's going on.


Good Luck with your quest for a Beta head cabinet. But; why would someone have one of those lying around? I think the short answer is that they wouldn't.
Maybe you can find a blown Beta head on eBay/Craig's List etc., but then they will probably want fixer upper amp money rather than useless empty wood box money for it.
Of course you never know, and as I said Good Luck with your search!

[Ugh]

Thanks for the reply, EdBass. I guess I'll load 'em up and see how they sound. I assumed that since they came with a 100 watt amp that they're probably at least 50 watts each...

As for the head cab, I figure it doesn't hurt to ask. Maybe someone has a dead beta they've already partially parted out? You never know! Ill probably just end up building a box myself though.

I'll also give them a close look for a code when I pull them from the combo.

[george]

An empty wooden enclosure for a Beta seies head is a simple DIY project. Most of them were made cheaply from particle board - you could use real wood  Nothing fancy - no sloped sides just a box. You could find the corners and handle here:

http://www.americanhandle.com/

and these guys are their distributor:

http://www.reliablehardware.com/

the correct tolex can be found on ePay or search this site.

[loudthud]

The speaker in the Beta 212 had Sunn part number 81-0118-00-90. (See this thread: http://sunnforum.ampage.org/index.php/topic,754.msg16586.html#msg16586 .) So you might find that number stamped on the back. You might also find a manufacturer/date code. 67-yyww would be Eminence, 137-yyww would be CTS. yyww is the date code. The first two digits are the year, the last two are the week 0-52.

[Ugh]

Well, I loaded the two no-name Sunn 12s into my empty Avatar 412 and they actually sound pretty good! They're a bit sweeter sounding than the Vintage 30s in my Orange 412, which is what I'm aiming for. The upper mid spike of V30s is a bit much for me. If anything, the Sunn drivers were just a bit bland sounding, but useable for sure. I used the Sunn-loaded cab with both the aforementioned Beta lead and my 78 Marshall 2203. I had both running pretty loudly, and the drivers didn't show any signs of being overpowered.

Now to find something to replace the V30s in the Orange cab...