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Cunningham CX 301A

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Hello,

Im new to this forum and this is my first post, Please forgive My ignorance as a newbie here.

Normally i spend way to many hours on PC forums.

SO, I'll cut to the chase.

I picked up a 1/2 dozen really awesome looking Cunningham CX 301A Bottles. And a triplet of CX 326s at an auction this past weekend. All Never Used and partially boxed (crumbling).

Id really like to build a lower output guitar amp out of these babies, But information is really limited.

I was wondering if anyone knows of a DIY site that might cover the information/schematics and or details that might help me get use of these lovelys.

Thanks
Trout
 
'01A's and 26's??

These are both DHTs from the 1920s and early 1930s and I believe are quite valuable (Well they are probably about SEVENTY years old!). Especially if they are the globe type. They are antique radio type valves, and are sought after by both antique radio restorers and SET enthusiasts, and they are getting rarer and rarer...

Sell them and buy some more suitable valves, 6V6s maybe? The bunch of old DHTs that you just bought may pay for the entire guitar amp if you're lucky enough to find someone who wants them bad enough.

On second thoughts, send them to me for safe disposal. Horrible things, those old valves.... :D

EDIT: Whoops, I should have said these are small-signal type valves, not really suitable for output valves
 
Value for NOS 01A and 26s is in the low teens, in $USD. Check fathauer.com. Not super valuable in dollar terms, but certainly not as boring as one of the billions of 12AX7s produced, some of which fetch silly money.

You might use them in a guitar amp - with the following things in mind:

00. It would be ultra-low power, ultra purist, ultra minimalist. (No tone stack) If a Mesa Boogie Triple Rectifier is your thing, move on.

0. Low-powered "practice" amp use only. You could use 2 26s with transformer phase splitter to drive 2A3s in push-pull for maybe 6 Watts. But oh boy, what a 6 watts that would be..... Tone for miles, guaranteed. Would need a highly efficient speaker to match - an old alnico 8" er, maybe.

1. They are driver tubes. You will need power tubes (45, 2A3, 47, 6V6) and output transformer(s) plus a whole power supply to make anything workable. I think $500 is a reasonable budget for the rest of the parts, even on ebay.

2. The 26 is *notorious* for hum. As in, plan to run it off of lead-acid brick style batteries. It's an old soldier, so you gotta treat 'em gentle.

3. I wouldn't take such an amp anywere - too delicate. Stationary home use only.

The old designs - tweed fenders, etc. are slight reworkings of even older designs, and other than a tone stack and lots of gain up front, there's nothing particularly exotic there.

Look for the November 2004 Audio Express magazine, there's a good linestage article that is a nice intro to tube amp topology.

Very much a death-or-glory kind of project - I'm not sure I'd say it's a beginner-level undertaking, but hey, how did the people in the 1920's learn if not on 01A and 26s.....

You must have some interest - you bought the tubes with a hopeful gleam in your eye, right?
 
Actually,, These tubes are Date labeled Aug 22 1927.

I also have the included in boxes factory specs sheets scanned And reading it, Im thinking its easy capable of driving more than just headphones, But Im No Expert.

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As you can see in the literature ( If I Linked It Correctly) They are indeed Amp Tubes.
Im Looking to build a real conversation piece for my home studio, And really hoped these would work.

Trout
 
AndyN said:
Value for NOS 01A and 26s is in the low teens, in $USD. Check fathauer.com. Not super valuable in dollar terms, but certainly not as boring as one of the billions of 12AX7s produced, some of which fetch silly money.


You must have some interest - you bought the tubes with a hopeful gleam in your eye, right?

Im thinking that this might be a really fun project .
I got about 100 really antique tubes at this sale. The previous owner was a medical test equipment engineer back in the day.

Myself, I am a mutant lol,
My Father was head tech for Barrett Magnavox in chicagloand back in the 60s, I grew up with these lovely bottles and eventually strayed away due to Well,, You Know " Women And Bars And Cars and Sex And Guitars lol

In My youth I did alot of interesting projects, Like in 69 I Built from scratch a laser and voice modulation unit to transmit voice over light. Seems primitive by todays standards, But for a 8th grader in 1969, That was a huge leap!

Now Im close to 50, My love for tubes has awakened again.
I just finished restoring a Seymour Duncan<snap,crackle&pop> convertable into real viable screamer.
Now Im looking for something really antique.

I found this forum about a month ago,, I think Ive read about a million posts on here,, I Must Say,, I LOVE IT~!!!


Welp,, Im going to continue researching my options on these tubes.
I'll keep You posted,, And Thanks for the wonderful Input.

Trout
 
astouffer said:
http://www.mif.pg.gda.pl/homepages/frank/short/064/0/01A.gif

This was meant for driving flea watt horn speakers or high impedance headphones. Don't expect any fat guitar sound. Trying to build an amp with these is like using cognac to start a fire. Sure it will work, but do you want to? If you want impressive tubes try an 845 or even a Sovtek 2A3 depending on your power needs.


Honestly, Its not about the power so much as the uniqueness of an amp like im concidering, Lately if heard sound clips from some incredable little amps .5 - 1.0 watt like the
NanoHead Sounds from a 12 volt wall-wart no less.

This is more a conversation piece project than a killer guitar amp project.
But alas,, You may be right. Finding the proper support parts is appearing more and more difficult by the hr.
Eh,, who knows, Ive spent about 20 hrs on research and so far have little more than a bad case of internet search fatigue lol

But, im not giving up just yet :)
Trout
 
Trout said:

But alas,, You may be right. Finding the proper support parts is appearing more and more difficult by the hr.
Trout


Ack, I wrote 6 or 7 encouraging paragraphs, and then the computer ate it. Argh.

To summarize: This is a golden age. You have the full menu of parts and technologies from the last century at your disposal. The forums unite all of us loonies around the planet to help one another, You can find the parts you need on eBay, and the friendly man in the big brown truck will bring it all to your doorstep.

Having said that, try Angela.com, Triode Electronics, or any of several other businesses, some of whom sponsor these forum websites.

Look for the old Western Electric schematics.. Your 26s and 01A are not too far removed from the WE101 tube.

I bet the ideas behind the WECO 42A or 9A, or the last two stages of the 86A could be turned into a dandy flea-power guitar amp. Find yourself some VT-47 output tubes -- That'd be unusual right there -- some cheap vintage universal output transformers, and you're on yer way.

[http://hereford.ampr.org/cgi-bin/tube?tube=VT-47]
 
Trout,

this is one of those suck-it-and-see projects, because you're working with that mysterious ingredient, 'tone'. I've not tried the 01A's, mainly because I don't have any, but I've been doing a lot of experimenting with vintage tubes, and so far, they've got a big yawn from every geetarist who's tried them, even those that look for a clean tone.

I think you're gonna have to just breadboard it out and try a whole lot of different values for the surrounding components to see whether you like it and/or until you find what you're looking for. Speaker and cab used will have a huge effect on the final result too.
 
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