single driver goodwill find

[bryana]

Saw these kind of homemade looking cabinets. Fairly solid. Fairly heavy. Removable back. Unable to tell much more about them but for ten bucks what the heck.
What a surprise when I hooked them up. Very nice bass and mids. Highs a bit lacking but the sound is so clear and detailed.
Open them up. As I thought a single driver. some type of vented cabinet with ports off to the sides. THere is a smaller hole in the upper left corner where a tweeter was either going to go or was never put in. It had a piece of plywood screwed over the hole. No crossover. Utah driver with wizzer cone. Eight inch with accordian type surrounds. Number on the driver says code 6108. I am thinking some type of kit or homebrew design.
What say you folks. Ever seen something similar?

Bryan Anderson

[bryana]

on my third disc now. Moody blues days of future past. Wow I am so impressed with these. Just pure sound no fatigue. These Utah drivers can take some juice too. I have driven them pretty hard and absolutey no complaints form them. I'm thinking I want tube amps now. Is this a slippery slope???

[SixCats!]

Hi Bry,

Welcome to the MADNESS! Hey, sweet little score you found yourself!
I have found several "lone" homemade speakers over the last few years myself. I don't know too much about UTAH drivers however.
Bry, you might want to consider (what I am planning to do) with my eight inch "full range" drivers and try using them in an OB (open baffle) speaker system. Also, find yourself a vintage MONO tube Amp, and you'll have a lot of fun (well...at least I do). Although I have NOT put together the OB system yet, I have several SINGLE speakers ranging in size from a couple of pounds (for example) "R hi-fi" speaker with 3" single driver to my vintage (circa 1959) Stephens E-3 Tru-sonic Horn Speaker (175 pounds).
Presently, I use a vintage SCOTT 99A TUBE MONO Amp on the aforementioned Speakers (as well as others). I VERY much enjoy the vintage sound on Classic Jazz, Blues and light Classical. Some of the eight inch drivers I have found include : HEAHTKIT, LAFAYETTE, RADIO SHACK, AMPEX and SEVERAL UNknown Japanese drivers. I also have a few 12" UNIVERSITY's Co-axials as well as a 15" Stromberg Carlson Co-axial. Oooh, and a couple of pairs of 3" R-hifi. You might want to do a Google search and check out
JE Labs for lots of cool info on OB systems. Best of luck to you with your new UTAH. Enjoy!

Regards,
SixCats!

[bryana]

Thanks Six cats. Have seen some open baffles. I wlays thought it was kind of the opposite of how things were supposed to be. I am now rethinking conventional wisdom seeing how these perform. Not sure I made it clear in my original post. I got a pair of cabinets. Been looking at some single driver sites. Just loving the simplicity of it all.

[arrow 68]

I have four Utah W 90, or U 90's. Purchased early in my thrifting days for $20. I was playing music loud and had one upside down and a loud bass boom knocked one over. They were on a carpeted floor. I thought that was hysterical. So I turned speaker woofer down, and it almost did the same thing again.
I would not get carried away with these. Although it does look like a well made driver. How much power can it take?

[bryana]

Did some more research on the enclosures these are in. The name for it is an Onken duct-loaded bass reflex enclosure. Lots of info out there on them. Found a set of plans that resemble mine.
http://www.studiomaudio.info/onken.html
Thanks for the warning arrow. I have neighbors nearby so I doubt I will hit that level of sonic bliss. I did play a bit louder than the norm and kicked the loudness switch in. No bad vibrations or bottoming out. Good advice though why push something this old.

[absolon]

. Wow I am so impressed with these. Just pure sound no fatigue.

Never know what you're missing until you try a speaker with no crossover. I'm partial to single 8" driver quarter wave pipes. I add a supertweeter with a high pass filter at 15kHz to catch the missing top end. The TQWP really reinforces the bass frequencies.

Sonic bliss.

[bryana]

i have noticed some of these people do add a super tweeter to capture the top end. I was kind of thinking about taking a spare EPI inverted dome with its high pass capacitor and trying it. Thinking a bit what you have done is the burhoe module with a fancier cabinet and different woofer and tweeter. Let the woofer naturally roll off and capture the tope end. Am I correct or oversimplifying. Do you have a reccomendation for a tweeter?
Thanks for your information

[stickman]

That Utah model looks to be a direct competitor for the highly regarded Electro-voice SP-8B model. Many Utah drivers were made with cloth surrounds that had little or no chemical treatments applied which were prone to disintegrating over time. The better models seem to have surrounds more in line with their competitors such as E-V or Jensen models offered at the time.

There is no harm in trying to use an EPI inverted dome tweeter but I suspect it will be far less efficient than the Utah driver and its output too low to provide a properly balanced sound spectrum. A tweeter of similar efficiency is the way to go if you had any idea what the specs were on that driver....

[bryana]

I understand. Well we have the code number off of the drivers
Given that perhaps someone will chime in with an efficiency rating for these Utahs.

[absolon]

i have noticed some of these people do add a super tweeter to capture the top end. I was kind of thinking about taking a spare EPI inverted dome with its high pass capacitor and trying it. Thinking a bit what you have done is the burhoe module with a fancier cabinet and different woofer and tweeter. Let the woofer naturally roll off and capture the tope end. Am I correct or oversimplifying. Do you have a reccomendation for a tweeter?
Thanks for your information

I suppose it may be similar to the Burhoe though that wasn't my intent. I've currently got 8" RS 1286C drivers that roll off about 15k and use 1" RS 1276B dome tweeters that match very well in terms of efficiency. I wanted the domes just to fill out the missing top end without being apparent when listening, this match does it well. They aren't classics, but they are pretty good drivers well suited for my application.

[clydeselsor]

Nice find! The cabinets look similar to the Argos "Californian", which were a kit based cabinet offered in the '50's. The grill cloth wraped around the enclosure like yours do.

[kretinus]

All the Utah drivers I've ever seen were in sound reinforcement or PA applications, given the brackets on the cabinets, I could see it in a church or ballroom.

[Rybeam]

Try some single guitar, acoustic or electric, thru them. The low to high mid range will blow you away. Taj Mahal, Leo Kottke or John Prine for example.

[kfa888]

Funny, my only single driver speaker was also a pair of Utahs rescued from Goodwill. I think I paid about $10 as well. These are 12" with a whizzer. I have OB plans for them as well and might just use EPI inverted domes as too! Strange.

BTW, Utah made lots of speakers for mid-fi apps as well as selling lots of drivers to others. Made good stuff but not great IMHO.

Here they are in their original Utah cabs (ported)

http://static.zooomr.com/images/4194991_6e7ec50169.jpg?r=360

http://static.zooomr.com/images/4194992_ed488534d3.jpg?r=360

http://static.zooomr.com/images/2477332_b7c14ae51c.jpg?r=360

http://static.zooomr.com/images/2477330_35ff12e518.jpg?r=360

[mrskinny]

If you're thinking about open baffle, just take the backs off the cabinets and try them.

[bryana]

kfa888 ...."speaker piggy"
Thanks for the images. Yeah those look familiar. Nice cabinets as well.
Well got the venerable parts express catalog out looking at some horns.

[bryana]

Doing some experimenting tonight. Waaay to cold to do anything else. Realized I had a pair of RS supertweeters that someone put on another pair of boxes I had. Borrowed them for some experimenting. Highs filled in but a bit brassy and harsh. I think there is potential here. Just need to find a suitable tweeter. Maybe change the capacitor value. Not bad though.