Leslie SuperTyfon horns were the replacement of the Tyfon horns. These horns are easier to maintain, in part due to interchangeable parts among all SuperTyfon models. Unlike the AirChime M series horns, the power chambers are interchangeable among any bell on any SuperTyfon horn, and unlike the early Tyfon models, the back cap does not screw on, but rather bolts on for easier maintenance. The SuperTyfon series was introduced in 1951 with the S3J and S5D. These horns sounded the same chords as the M3 and M5 offered by AirChime at the time (A-major triad and A-major 7th). Just after these were announced, Leslie added the S3E and S5A to their offerings. Then in late 1952, not even two years after the SuperTyfon line was introduced, all of these models were dropped in favor of the S3L and S5T, changing Leslie's style forever. Since then, other offerings have joined the SuperTyfon line, but the original four horns have never been reintroduced. SuperTyfon horns have been a mainstay of many railroads since their introduction over 50 years ago, and they have changed very little over that time. Though no railroads are known to have purchased SuperTyfon horns in the past couple of years, Leslie Controls still offers these products.
power chamber construction
The primary changes to the SuperTyfon line over the years have been with the power chambers. When they were first introduced in 1951, the power chambers were cast bronze, with two-piece diaphragms consisting of a stainless steel disc and ring. The back cap also has a second disk permanently riveted in place on the back cap, called the spreader plate. Because of this disk, the back cap has a slightly domed appearance. The general form of these chambers is round, with six tabs protruding around the circumference, which are used to bolt the back cap to the rest of the power chamber. Power chambers of this style are referred to as "tab-back" power chambers.
Bronze power chamber construction lasted until about 1958, when power chamber construction was switched to aluminum.
The aluminum chambers are more prone to wear, but are cheaper to manufacture and weigh a lot less than their bronze counterparts.
Around 1968, this style was changed to a completely round power chamber.
Metal was added so that the new outer circumference was the outside of the bolt circle.
This strengthened the construction, since it was found that the tabs on older chambers tended to snap off if hit the wrong way.
These chambers retained the same diaphragm construction inside, including the domed back cap with diffuser plate.
Because of the round appearance, and the domed back cap, these newer chambers are referred to as "dome-back" or "round-back" power chambers, even though the tab-back chambers had a domed back.
Over time, it was found that SuperTyfon power chambers were prone to fail when dirt, grease, and other contaminants were introduced into the air line. While strainers can help reduce this, the railroad atmosphere is guaranteed to be dirty, and so it is impossible to keep all contaminants out. To help reduce the chance of failure, Leslie built a new power chamber, called the RS power chamber, or "improved" chamber. These are similar in appearance to dome-back power chambers except that the back is generally flat with a large spike protruding from the rear of the back cap. The purpose of this spike is described in the maintenance section of this site. Suffice to say here is that it helps provide a restoring force for the diaphragm. The diaphragm is also different on these new chambers. There is now just a single stainless disk, with a silicone cushion ring that seats in the back cap. The silicone ring prevents wear to the outer edges of the diaphragm. Because of the spike on the back cap, the RS power chambers are referred to as "spike-back" power chambers. Spike-back power chambers are much less prone to failure than their dome-back and tab-back counterparts.
The very early bronze power chambers had no way to meter or restrict the air flow from the manifold into the power chamber, forcing a "full-orifice" configuration. However, within a year or two of the SuperTyfon's introduction, a method was found by which a hollow aluminum dowel was attached to the orifice on the power chamber. A hole was drilled in this "orifice dowel" so that the hole would line up with the air feed on the manifold for that chamber. Depending on the size of the drilled hole, the amount of air to each chamber could now be restricted without permanently modifying or recasting power chambers, allowing "variable-orifice" horns. Variable-orifice horns wear slower and tend to be more balanced at close distances. Just after this invention came to be, Leslie changed the location of the dowel from the power chamber to the bell, now simplifying the job of aligning each orifice size with the correct bell. All of this occurred within the first year or two of production. Today, each bell is offered in several different orifice sizes.
| powerchamber_040215_1.jpg | the insides of a tab-back power chamber, which are identical to those of a dome-back power chamber | |
| powerchamber_040215_2.jpg | a tab-back and dome-back chamber side-by-side | |
| s3l_030614_2.wav | here is an S-3L with tab-back power chambers | |
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| rs3l_020622_1.wav | compare that to this sound clip of an S-3L with RS-style, spike-back power chambers |
bell construction
The bell construction has also changed slightly over time. Unlike AirChime bells, Leslie bells are not numbered 1, 2, 3, etc. Instead they are numbered based upon the frequency of the sound they produce in Hertz. For instance, a 247 bell blows 247Hz, or B below middle C. Three-digit bell numbers were used in the first two years of production only, and were cast on a raised rectangle at the base of the left side of the bell. When the S-5D, S-3J, S-5A, and S-3E were discontinued in late 1952, bell numbers were shortened to two-digits, dropping the last digit. The 554 bell is now just a 55 bell. Also at this time, the 247 bell was replaced by the 25 bell, which plays a C instead of the 247's B, and the 277, 330, and 392 bells were completely dropped from Leslies offerings. All the other bells were retained and shortened to two-digit numbers. Within the first couple of months of two-digit bell production, the numbers were moved to the right side of the bell instead of the left, and at the same time, the "Leslie" or "Leslie SuperTyfon" started being cast into the left side of the bell.
When the SuperTyfon line was first released, Leslie did not have the capacity to cast the large 247, 277, 311, and 370 bells as one piece. Instead, these bells were cast as two pieces and then welded together. This continued past the introduction of the S-5T and S-3L, up until about 1955. The only exception is the 370 bell, which started being cast as one piece around 1952. (Oddly, the two-piece 370 bells played F, and not F#, too.) Therefore, all 247, 277, and 311 bells and the earliest 370, 25, and 31 bells, have a unique ring halfway up the throat where the two bell pieces were welded together. The last main difference in the bell construction is that over time, each bell was recast, with the number appearing in a raised circle instead of a raised rectangle. The last bell to be recast is supposedly the 37 bell, being recast as late as the early 1970s, though the actual dates are unknown. Also of note is that early 55 bells did not have the 55 cast in a raised rectangle, but rather the 55 is just raised on the bell surface. Later 55 bells have the number cast in a raised circle.
| s2m_weart_1.jpg | Ray Weart's old S-2M with bronze power chambers and two-piece 31 bell - note the numbers are in rectangles, not circles | |
| s5t_weart_1.jpg | Ray's 1952 S-5T - notice some of the bells have numbers on opposite sides as other bells |
other differences
There are a few other items of note which should be mentioned. First, the bottom of the 25 bell, unlike the 247, appears to be "shaved off". This is intended, as the bells are cast like this, not shaved or filed after the casting. Also, the 440 bell, unlike the rest of the original bells, has a seat for an O-ring, which is used to seal the bell to the power manifold in the place where the orifice tube is on newer bells. New 44 bells have a different unique feature. Cast next to the "44" are the letters "BAF" on a raised diamond. This supposedly represents a new foundry through which Leslie produces their 44 bells (and possibly their other bells as well).
Horns that were produced up until about 1972 have been date stamped. The bottom-rear of the manifold, where the horn is bolted down, will have a 2-digit number stamped in, representing the last two digits of the casting date. Only complete horns were date stamped; replacement manifolds do not have dates stamped in them. Also, the spike-back power chambers have three different styles, but in outward appearance only. The earliest chambers have "Patent Pending" cast into the back cap, along with "Parsippany, NJ". Newer chambers have the patent number instead. The newest runs (since Leslie moved to Tampa) have "Tampa, FL" cast into the back caps instead of Parsippany.
designations
The designations for SuperTyfon horns can get quite tricky, though thankfully not as tricky as Tyfon horns, since the designations have not changed over time. Designations start with the letter "S", supposedly standing for "SuperTyfon". Next is a dash followed by the number of bells in the chime (2, 3, 4, or 5), directly followed by a letter corresponding to the chord the horn produces. This simple designation represents a factory-configured, variable orifice, all-bells-forward configuration of the given horn. For example, an S-5T represents a 5-chime SuperTyfon on the standard 5-chime manifold, variable orifices to each bell, all-bells-forward, and the factory-standard arrangement of bells on the manifold. By adding various prefixes and postfixes, any alternate configuration can also be classified.
The first prefix is the letter "R", which designates a horn with the newer spike-back chambers. If this is the case, our S-5T is now considered an RS-5T. The other "prefixes" are actually inserted between the leading S and the dash, and are as follows:
- "L" - low-profile 3-chime or 5-chime manifold
- "U" - very low profile 3-chime manifold ("U" for Universal)
- "J" - narrow 3-chime manifold used by the S-3J (cannot be used with "L" or "U" prefix)
- "R" - one bell reversed
- "RR" - two or more bells reversed
- "O" - normal arrangement of bells on the manifold from left to right has been reversed or changed
- "F" - full orifices
- "X" - several different meanings - in the case of the SL-4T, "experimental" - in the case of the S-2M, optional secondary air inlet - other uses unknown
Last, there are special designations for SuperTyfons using only one size bell. Single-note horns are based as an S-XX, where XX is the number of the bell. Therefore, an RS-25 is a single-note horn using the 25 bell and a newer RS-style power chamber. Leslie also offered two-bell horns with duplicate bells, one facing each direction. These would be classified as S-XX-2, where XX is the number of the bell. An S-44-2 would be a pair of 44 bells on a 2-chime manifold, one facing each direction.
Following is a table of all known chords available for multiple-note SuperTyfon horns, past and present, along with the bells used to produce them and the notes played. Since the 25 bell plays C, and not B as advertised, I've revised the table to reflect the notes heard, not those advertised. As such, the only horns that have a "B" bell are those with a 247 bell.
| Chord | Bells Used | Chord | Notes |
| S-2A | 25, 31 | minor third | C, D# |
| S-2B | 31, 37 | minor third | D#, F# |
| S-2G* | 31, 55 | n/a | D#, C# |
| S-2H* | 37, 48 | major third | F#, A# |
| S-2M | 31, 44 | tritone | D#, A |
| S-3B | 37, 44, 55 | F# minor | F#, A, C# |
| S-3C | 25, 37, 55 | n/a | C, F#, C# |
| S-3E** | 247, 277, 370 | n/a | B, C#, F# |
| S-3J** | 277, 330, 440 | A major triad | C#, E, A |
| S-3K | 31, 37, 48 | D# minor | D#, F#, A# |
| S-3L | 25, 31, 44 | n/a | C, D#, A |
| S-3P | 25, 37, 55 | n/a | C, F#, C# |
| S-3T | unknown | unknown | unknown |
| S-4T | 31, 37, 48, 55 | D# minor 7th | D#, F#, A#, C# |
| S-5A** | 247, 277, 311, 370, 440 | B major 7th | B, C#, D#, F#, A |
| S-5D** | 277, 330, 392, 440, 554 | A major 6th | C#, E, G, A, C# |
| S-5T | 25, 31, 37, 44, 55 | C dim with flattened 9th |
C, D#, F#, A, C# |
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* the S-2G and S-2H combine to create an S-4T ** only offered in the first year of production - also, early S-3Es played B, C#, F, and early S-5As played B, C#, D#, F, A, identical chords to the A-125-3E and A-125-5A | |||
| kaspriske_030614_3.jpg | Ed Kaspriske brought along his S-3KJ to Oak Ridge 2003 - note the J-style manifold on this horn | |
| s5d_030614_1.jpg | on the S-5D and S-5A, a narrower, taller manifold was used; the earliest manifolds which pre-dated this one didn't have the cross braces between manifold ports, either | |
| s5d_030614_5.jpg | Ken Kanne and Ken Lanovich did an excellent job restoring this horn to it's former glory | |
| s5t_031231_2.jpg | here is an S-5TFRRO that I will be restoring when time allows | |
| sl4t_weart_1.jpg | a close-up of one of Ray Weart's ex-Amtrak SL-4TXs | |
| sl4t_weart_2.jpg | two of Ray's SL-4TXs, one with Amtrak-installed snow cones | |
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| s25_weiler_1.wav | an S-25 on one of Blue Mountain and Readings RDCs in active service - notice the squealing which was common on many S-style power chambers | |
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| s2m_011117_1.wav | my S-2M - this horn was common on many of NYC's E-8s | |
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| s3j_030614_1.wav | the S-3J is a rare find, and pretty-sounding, too | |
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| brw1853_011125_2.wav | the S-3J's replacement, the S-3L - even the dog doesn't think it's very musical! | |
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| ns_010915_1.wav | this RS-3L was recorded about a mile away from Conrail's main (now Norfolk Southern) in Three Bridges, NJ | |
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| brw1853_030104_1.wav | here is my S-3K while in active service, recorded close to a mile in front of the train | |
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| s4t_011218_2.wav | I converted my S-5T into an S-4T temporarily, with good results | |
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| s5d_030614_4.wav | here is an original S-5D, tuned to A Major 7th, not A Major 6th as most reproductions are | |
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| rs5t_030614_2.wav | an RS-5T blown at Oak Ridge - it's easy to hear why many people consider this the greatest of air horns | |
last updated 09.03.2005