Joe Spann - Posted - 11/18/2009:  06:34:45

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Gibson introduced their top tension banjo series in 1937. These instruments
represented almost a complete design break with any banjos that Gibson had produced before. Radiused fingerboards, solid wood resonators, "art deco" style inlays and pegheads as well as the top tensioning stretcher band were all new for Gibson. The style 12 featured chrome plated metal parts and walnut lumber.

The first style 12 banjo was a tenor, shipped on 9 July 1937. The original production run of this model ceased with the onset of World War II in 1941.

Because Gibson's shipping records exist for the entire period of style 12 production we can know exactly how many were shipped, thus giving a very good idea of how many were produced.

The Gibson shipping ledgers show the following information:

TB-12 19 units shipped
PB-12 4 units shipped
RB-12 7 units shipped

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Edited by - Joe Spann on 11/18/2009 07:28:37

Mike Johnson - Posted - 11/18/2009:  08:37:00

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Thanks Joe. Does 7 "units shipped" mean 7 individual banjos or 7 events of shipping? That is to say are there 7 RB12s in existence or are returns and reships represented in this total?

Mike Johnson

rexhunt - Posted - 11/18/2009:  08:40:30

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Thanks Joe. Talk about rare!! I love the sound of a walnut banjo. The only time I was at the Gibson Showcase in Nashville years ago, the only two banjos that sounded any good at all were an RB-4 and an RB-12. That 12 was HEAVY!

Rex

Joe Spann - Posted - 11/18/2009:  09:01:29

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Mike,

Seven units shipped means seven unique and individual banjos.

#411-1
#411-2
#667-1
#667-2
#960-1
#981-1
#981-2

keithmcgreggor - Posted - 11/18/2009:  09:53:07

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Joe,

Since this was a very small number of produced banjos, can you provide here the exact counts for each batch, just as you have for the TB-12s? In that way, I can compare how well the estimation method I outlined in the other post would have worked out.

Keith

Mike Johnson - Posted - 11/18/2009:  10:20:09

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We'll have to wait for the book.The "trailers" have been terrific! Two thumbs (index and middle too-the full roll) up!

Mike Johnson

Shimdog - Posted - 11/18/2009:  10:23:37

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Very interesting, Joe. Thank you for sharing this information. Does this mean that other banjos listed as RB-12s in a site like Banjophiles (realizing that the authenticity of many banjos is based on owners' opinions) were shipped as other models? For example, the site also shows the follow banjos as an RB-12:

651-3
F690-4
E2791-3/651-3 Shelor
5882-1
9412-2

Any thoughts on this?

Thanks,
Paul

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"And those who were seen dancing were thought to be insane by those who could not hear the music." - Friedrich Nietzsche

RB3Banjo - Posted - 11/18/2009:  11:52:07

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quote:

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Originally posted by Joe Spann

RB-12 7 units shipped

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Elsewhere I believe Joe said that 8 RB-18's shipped. George Gruhn and Walter Carter say in their Vintage Guitar Magazine article (May 2007) that 28 RB top tensions were shipped from 1937 through 1941.
Ergo, 13 RB-7's shipped.
RB

Joe Spann - Posted - 11/18/2009:  13:01:31

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Paul,

Your question "Does this mean that other banjos listed as RB-12s in a site like Banjophiles (realizing that the authenticity of many banjos is based on owners' opinions) were shipped as other models?" The answer is yes, exactly.

You asked about the following banjos:

F690-4 - This banjo does not meet the catalog description of a style 12 and is more properly classified as a "floorsweep" model. It originally shipped from Gibson on 19 September 1940 as an "RB-7." It is my also understanding that the FON in the rim of this banjo is 181-1 and that it has nickle plated hardware.

E2791-3/651-3 The Sammy Shelor banjo - This banjo does not meet the catalog description of a style 12 and is more properly classified as a "floorsweep" model. It originally shipped from Gibson on 23 April 1943 as an "RB-7."

5882-1 This banjo does not meet the catalog description of a style 12 and is more properly classified as a "floorsweep" model. It originally shipped from Gibson on 28 September 1943 as an "RB-7."

9412-2 Is the Factory Order Number of a rim supposedly found in a style 12 banjo. However, no banjo with this FON can be found anywhere in the shipping ledgers.

Joe Spann - Posted - 11/18/2009:  13:08:49

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RB,

Gibson shipped 31 banjos which they designated as RB-7's between 1937 and 1944. They shipped 7 RB-12's and 8 RB-18's for a total of 46 top tension flathead, original five string Mastertones.

keithmcgreggor - Posted - 11/18/2009:  13:10:02

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Ok... let's revise the estimate then, based on the (still incomplete) information we collectively have (Joe, provide the actual numbers and we can dial this in):

The formula you use (and the one the Army used) to estimate actual production is this:
estimate = (maximum number seen - 1)*( number of samples + 1) / (number of samples)
and if the maximum count number is 1, you by default take it as an estimate of 1.

Taking Joe's remarks into account, we have these (apparently true) RB-12s:

411-2 ==> (2-1)*(1+1)/1 ==> 2
651-3 ==> (3-1)*(1+1)/1 ==> 4
960-1 ==> 1

2+4+1 = 7 estimated RB-12s produced, based upon what we've seen so far. Good agreement.

- Keith

keithmcgreggor - Posted - 11/18/2009:  13:19:27

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Oops... Let's take a closer look.

If these are the actual and only numbers shipped by Gibson for true RB-12s:

#411-1
#411-2
#667-1
#667-2
#960-1
#981-1
#981-2

Then here's the calculation:

411-2 ==> (2-1)*(2+1)/2 ==> 1.5 round up to 2
667-2 ==> (2-1)*(2+1)/2 ==> 1.5 round up to 2
960-1 ==> 1
981-2 ==> (2-1)*(2+1)/2 ==> 1.5 round up to 2

2 + 2 + 1 + 2 = 7. Again, good agreement.

So if we have complete information (that is, if we can account for each and every banjo in the batches), then the tank estimation method converges very nicely, as shown.

My previous post seems to erroneously included 651-3 and omitted the 981 batch. Joe, what was the 651 batch supposed to be?

- Keith

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Edited by - keithmcgreggor on 11/18/2009 13:21:08

Joe Spann - Posted - 11/18/2009:  13:24:33

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Keith,

I did review your posting on the previous style 12 thread and the production estimates you produced using the tank method. I can tell you that your predicted totals weren't close to the actual shipping numbers from the ledgers. As you stated, the validity of any calculation using the tank method depends on having a majority of the original data. I think the problem with applying the tank method here is exactly that. Lists like the one at Banjophiles contain only a small fraction of all the top tensions produced by Gibson.

Joe Spann - Posted - 11/18/2009:  13:31:11

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Keith,

Your question, "Joe, what was the 651 batch supposed to be?"

The original batch #651 in 1932-34 was a group of L-1 guitars.

The shipping ledgers do not show any banjos shipped under that batch number. However, the Sammy Shelor banjo has a rim with #651-3 stamped inside. So, there may have been such a batch. But again, no other examples of banjos from this batch appear in the original ledgers.

BanjoLink - Posted - 11/18/2009:  16:48:02

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This is fascinating! I would guess that all of the totals of the 12's are way too small for the tank method to work, except for the fact that since no number greater than "2" exists, I guess you could assume that 2 were the maximum made (if that is the way the mehtod works). Seems like it would work better where the numbers were in the hundreds, so that if you missed by 10%, you would still be pretty accurate - for government work anyway!

Thanks Joe for this information. It really shows how rare some of these great banjos are. It also makes me want to kick myself for not going after some of these models years ago!!!!

keithmcgreggor - Posted - 11/19/2009:  08:49:56

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quote:

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Originally posted by Joe Spann

Keith,

I did review your posting on the previous style 12 thread and the production estimates you produced using the tank method. I can tell you that your predicted totals weren't close to the actual shipping numbers from the ledgers. As you stated, the validity of any calculation using the tank method depends on having a majority of the original data. I think the problem with applying the tank method here is exactly that. Lists like the one at Banjophiles contain only a small fraction of all the top tensions produced by Gibson.

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Completely agree with respect to "known" examples. However, once I had the precise numbers from you, as I've shown above, the estimate appears to converge exceptionally well.

Perhaps we could take a look at another small run set (for example, the RB-18s), and compare the shipping records with the estimates (as calculated both from the imprecise "known" examples from various lists and from the actual shipping records themselves). [You can reach out to me privately via email if you don't want to divulge some of this yet.]

- Keith

Shimdog - Posted - 11/19/2009:  11:25:06

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Joe,

Thanks again for sharing all of this, and for answering my question. It is all so fascinating. I happen to own a TB-12 and had no idea how few were produced.

Paul

musician - Posted - 11/21/2009:  12:30:55

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According to the shipping records I saw, my TB-12 shipped in June. #1393-2 (sorry but I cannot find the copy I have of the actual record).

Only 30 total 12's. Wow.

Oldtwanger - Posted - 11/21/2009:  14:29:54

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quote:

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Originally posted by musician

According to the shipping records I saw, my TB-12 shipped in June. #1393-2 (sorry but I cannot find the copy I have of the actual record).

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1393-2 TB-12 shipped July 9, 1937 as a 'sample', again on July 20, 1937 as a 'sample', September 4, 1937, presumeably as a 'sample' again, and finally on August 12, 1938.

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Edited by - Oldtwanger on 11/22/2009 04:32:13

musician - Posted - 11/22/2009:  04:58:53

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Very cool. Thanks!

El Dobro - Posted - 11/22/2009:  06:56:55

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Here's a good one EA-5578. I thought it was a curly maple TB-12, but someone peeked into the records and said it was a chrome-plated 18?