Why The "Advanced" in the Advanced Jumbo Guitar

[rustystrings]

I must respectfully disagree with the statement by Gruhn that "Advanced" refers to bracing position in pre-war guitars. I was under the impression that Advanced (as in Advanced Jumbo) had to do with scale length. The AJ was the first Gibson flattop to use a 25 1/2-in scale, followed by the Super Jumbo 200, etc. I have a memory of reading that the Advanced terminology came out of the archtop end of things and was applied to the L-5, which went from the 24.75 to the 25.5-in scales in the same general time period, while other, less pricey instruments stayed with the classical shorter Gibson scale. The assorted Super 300, Super 400, etc. guitars also had the longer scale. I suspect a trawl through mid-30s Gibson promotional stuff will turn up the answer.

[tpbiii]

I must respectfully disagree with the statement by Gruhn that "Advanced" refers to bracing position in pre-war guitars. I was under the impression that Advanced (as in Advanced Jumbo) had to do with scale length. The AJ was the first Gibson flattop to use a 25 1/2-in scale, followed by the Super Jumbo 200, etc. I have a memory of reading that the Advanced terminology came out of the archtop end of things and was applied to the L-5, which went from the 24.75 to the 25.5-in scales in the same general time period, while other, less pricey instruments stayed with the classical shorter Gibson scale. The assorted Super 300, Super 400, etc. guitars also had the longer scale. I suspect a trawl through mid-30s Gibson promotional stuff will turn up the answer.

 

That is indeed one of the "advanced" features on the AJ. Here are two late 1936 Gibsons -- an AJ and a Jumbo35 (this one is 960-12, the only guitar in the shipping ledger called a Trojan that also has the FON -- thus the only provable Trojan). I measure the scale length at the D string. 25.5" and 24.9"

That is not much, but much is made of it.

Best,

-Tom

[olie]

The book " Gibson's Fabulous Flat-Top Guitars " has a section in which the authors try to explain what AJs are about.They state that on many examples,starting in 1936 the interiors were identical " including the plane marks; it's probable that the same luthier hand-tuned each and every AJ top that left the factory." Apparently Ren Ferguson thought so too. "The dimensions of the sound box were 16 1/16" wide at the lower bout and 20 1/2" long with the sides 4 13/16" deep at the rear and 3 7/8" at the front.The thin red spruce top is tapered at its edges and finished with a particularly striking sunburst under which are top braces measuring approx. 1/2" high and 1/4" thick.The two tone bars( one fewer than the early J-35s of the time) run parallel, with a distance of 1 3/16" between them,angling off at the treble x-brace at just over 60 degrees.

Located 1" below the 4" sound hole is the x-brace itself, whose 102 degree angle accounts for some of the wide open, expansive tone the instrument is noted for.At 11/8" wide the maple bridge pad is relatively small.The large back braces, roughly 5/16" thick and 1/2" high on the front two and 3/4" thick and 3/8" high on the pair at the rear are typical of the era.The sides' supports are made of quartersawn spruce."

"Against such a a large body the Brazilian rosewood bridge seems very small, in fact measuring .910" wide and 6.1" long and requiring two tiny bolts to help hold it down.The bridge tapers on the treble side and features a bone saddle.

I appologize for the length of this entry but some of you might not have this book so I set it down here for you.

John Thomas of "Kalamazoo Gals" fame found some discrepancies in the book cited here but I picked a copy up on-line from Abe Books and I think that it's a really interesting volume with a lot of great photos. I hope this helps to add to the general understanding of the issue brought up here.

[Alex_78]

The book " Gibson's Fabulous Flat-Top Guitars " has a section in which the authors try to explain what AJs are about.They state that on many examples,starting in 1936 the interiors were identical " including the plane marks; it's probable that the same luthier hand-tuned each and every AJ top that left the factory." Apparently Ren Ferguson thought so too. "The dimensions of the sound box were 16 1/16" wide at the lower bout and 20 1/2" long with the sides 4 13/16" deep at the rear and 3 7/8" at the front.The thin red spruce top is tapered at its edges and finished with a particularly striking sunburst under which are top braces measuring approx. 1/2" high and 1/4" thick.The two tone bars( one fewer than the early J-35s of the time) run parallel, with a distance of 1 3/16" between them,angling off at the treble x-brace at just over 60 degrees.

Located 1" below the 4" sound hole is the x-brace itself, whose 102 degree angle accounts for some of the wide open, expansive tone the instrument is noted for.At 11/8" wide the maple bridge pad is relatively small.The large back braces, roughly 5/16" thick and 1/2" high on the front two and 3/4" thick and 3/8" high on the pair at the rear are typical of the era.The sides' supports are made of quartersawn spruce."

"Against such a a large body the Brazilian rosewood bridge seems very small, in fact measuring .910" wide and 6.1" long and requiring two tiny bolts to help hold it down.The bridge tapers on the treble side and features a bone saddle.

I appologize for the length of this entry but some of you might not have this book so I set it down here for you.

John Thomas of "Kalamazoo Gals" fame found some discrepancies in the book cited here but I picked a copy up on-line from Abe Books and I think that it's a really interesting volume with a lot of great photos. I hope this helps to add to the general understanding of the issue brought up here.

 

I have it, it's a great book, but right now there is more info on these guitars (like FON numbers) and it would be good to "expand" it.

 

I also noticed the tops of AJs are usually on the thin side.

[tpbiii]

The book " Gibson's Fabulous Flat-Top Guitars " has a section in which the authors try to explain what AJs are about.They state that on many examples,starting in 1936 the interiors were identical " including the plane marks; it's probable that the same luthier hand-tuned each and every AJ top that left the factory." Apparently Ren Ferguson thought so too. "The dimensions of the sound box were 16 1/16" wide at the lower bout and 20 1/2" long with the sides 4 13/16" deep at the rear and 3 7/8" at the front.The thin red spruce top is tapered at its edges and finished with a particularly striking sunburst under which are top braces measuring approx. 1/2" high and 1/4" thick.The two tone bars( one fewer than the early J-35s of the time) run parallel, with a distance of 1 3/16" between them,angling off at the treble x-brace at just over 60 degrees.

Located 1" below the 4" sound hole is the x-brace itself, whose 102 degree angle accounts for some of the wide open, expansive tone the instrument is noted for.At 11/8" wide the maple bridge pad is relatively small.The large back braces, roughly 5/16" thick and 1/2" high on the front two and 3/4" thick and 3/8" high on the pair at the rear are typical of the era.The sides' supports are made of quartersawn spruce."

"Against such a a large body the Brazilian rosewood bridge seems very small, in fact measuring .910" wide and 6.1" long and requiring two tiny bolts to help hold it down.The bridge tapers on the treble side and features a bone saddle.

I appologize for the length of this entry but some of you might not have this book so I set it down here for you.

John Thomas of "Kalamazoo Gals" fame found some discrepancies in the book cited here but I picked a copy up on-line from Abe Books and I think that it's a really interesting volume with a lot of great photos. I hope this helps to add to the general understanding of the issue brought up here.

 

That book has many mistakes, including about the AJ. The problem was when they wrote it they assumed that Gibson was more consistent than they were -- so when they saw one or a few, they thought they had seen them all. It was a good try for the time, but that time is long passed. Many (including me) were amazed when they reprinted it without many corrections.

They say "examples,starting in 1936 the interiors were identical" and "The two tone bars( one fewer than the early J-35s of the time) run parallel." Well our 1936 AJ shown above has three tone bars with the identical brace layout to our 1936 Trojan. You don't have to look far to find such problems.

Best,

-Tom

 

 

 

[olie]

That book has many mistakes, including about the AJ. The problem was when they wrote it they assumed that Gibson was more consistent than they were -- so when they saw one or a few, they thought they had seen them all. It was a good try for the time, but that time is long passed. Many (including me) were amazed when they reprinted it without many corrections.

They say "examples,starting in 1936 the interiors were identical" and "The two tone bars( one fewer than the early J-35s of the time) run parallel." Well our 1936 AJ shown above has three tone bars with the identical brace layout to our 1936 Trojan. You don't have to look far to find such problems.

Best,

-Tom

I had a feeling that no one was referring to this book,for a reason, and thought: a little light could be brought to bear on this by some with much more knowledge. Tpbiii ( and others) could put a better reference source together to correct some of the points that seem to be in error. I only to set the record straight for younger Gibson fans who will want to know the real goods when their predecessors are no longer around .This is history in the making.

BTW I'd really like to hear from Mr. Thomas on these subjects. Please.

[slimt]

I think that was a big part of it. 1936 was the middle of the depression, and nobody was doing well. Not many guitars had been sold, but the 14-fret larger body guitars -- starting with the Martin OM (1929) and Dreadnoughts (1934) as well as the Gibson Jumbo (1934) -- had got the attention of musicians. Historically, Gibson had always used mahogany B&S for their top of the line while Martin used rosewood.

 

In late 1936, Gibson made a major marketing and product line move, pretty much across a great majority of their products. They begin (re)naming the models according to their (often reduced) price. Gibson was mainly in the archtop guitar business -- flattops were pretty new for them. Thus you got the L-35, L-50, L-75, and Super-400. They kept the L-4 and L-5 -- top of the line -- designations. They also renamed stuff (with really minor changes) in the banjo area -- TB/PB/RB-3 became TB/PB/RN-75, etc.

 

In the big flattop area, the Jumbo -- the top of the line -- was a relatively new guitar. Like the Martin D-1/D-18 and the D-2/D-28, the Jumbo evolved from earlier (Roy Smeck) large flattop 12-fret (Hawaiian) body.

 

The big bang came in late 1936. As Red said, they dropped the Jumbo and introduced a less fancy (but same specs) model whose internal name was Trojan, but later morphed into Jumbo35 and J-35. The Advanced Jumbo was officially introduced at that time -- it had a long scale, different slightly more tapered sides, wider x-braces, fancy fretboard inlays, and (most importantly) rosewood B&Ss. It is widely believed the rosewood -- which was rare in the Gibson line -- was there to compete with the relatively new Martin top-of-the line D-28 model.

 

The Jumbo35 held it specs for about a year, but then adopted the AJ body shape -- which is the classic shape we now know in the J-35, J-45, J-55, SJ, C&W, and on-and-on -- the Slope Gibsons.

 

Here is a mid thirties family picture -- back: 1936 Trojan/Jumbo35, 1936 Advanced Jumbo, 1935 Jumbo. Front: 1936 Roy Smeck Stage Deluxe, 1935 Roy Smeck Radio Grande (the other big RW Gibson)

 

 

Here they are with there period Martin competition -- Gibson in front, Martins in back.

 

 

Here are some Js from 1935 to 1954.

 

Let's pick,-Tom

 

 

you must have a real good job.. Nice Collection you have..

[tpbiii]

Now that's just showing off.

 

 

 

 

 

You don't want to go there.

 

you must have a real good job.. Nice Collection you have..

 

Just a lot of time -- now near 50 years -- and a joint plan with a really good wife.

 

Best,-Tom

[Bozz]

That's how my 2008(?) is. It's great sounding. The TV back bracing, though taller and thinner than the AJ back bracing, is different from the back braces on the J-35 Standard, which are the same as the J-45 Standard if memory serves.

 

I also have a Southern Jumbo True Vintage from maybe 2010. You'd think it would be build exactly like the J-45 True Vintage but its back braces are different from that!

 

Red 333

I have a 2015 Sheryl Crow Southern Jumbo Supreme that has the tall and thin back bracing as well. Perhaps it's the same bracing as the Southern Jumbo TV.

 

The Gibson website information from 2015 described the SCSJ has having a "Radiused top with 1930's advanced scalloped bracing with hot hide glue". The fact that modern day Gibson uses the term "advanced" with reference to bracing probably adds to the confusion that this thread is discussing about what it was originally intended to mean on the AJ.

[Red 333]

 

The fact that modern day Gibson uses the term "advanced" with reference to bracing probably adds to the confusion that this thread is discussing about what it was originally intended to mean on the AJ.

 

 

Most certainly.

 

Red 333