The Siemens Taurus locomotives make the absolutely best sound of all trains. It literally plays a musical scale while accelerating from a stop. There are countless videos of it on KZfaq.

I always felt that a train’s motor sounds made up a part of its “identity”, and I also kinda wondered how the sounds are made. I know part of it is due to electromagnetically-induced noise (coil whine), but I always wondered why even the same type of motors might sound different when they are from different manufacturers, etc. This video definitely provides a good overview of what I always wanted to know.

This is a brilliant video! I was always wondering why electric trains make that sound! I personally love motor noise. My favourite motor noise comes from the Siemens Taurus, Class 455, Class 323 and Desiro.

The 1996, and 2009 stock makes the nicest noises

The synchronous (pattern based) mode is used to reduce motor current harmonics. The method is called "Selective Harmonic Eliminated PWM" or just "SHEPWM". And you are right, the transition between patterns is because of the limited maximum switching frequency - very well explained! For asynchronous carrier based modulation there are many methods. More common nowadays is the Space Vector Modulation (because it creates less current harmonics) and in older drives you would find 'center-aligned' or 'edge-aligned' SPWM methods. All of these carrier based modulation methods can be used with a random generated carrier in a given range to reduce harmonics even further.

6:00 Those DC motors sound so beautiful. Outdated technology? Yes. But I don't care. It is a thing of beauty. Those newer trains that make a high-pitched "eeeeee" sound drive me a little crazy. I understood the electrical part, but now I know why the different drive systems sound different. Thanks, Beno!

I like that sound the jubilee line 1996 stock makes.

These sounds, I must say, for some reason I find them so satisfying : D

I thought it was because they recycled parts from the war of the worlds tripods.

Fantastic video! I've ridden on many of those types of trains over many years and gradually figured much of this out but it's great to see so much more. I witnessed a 1990's BART train blow a motor and drive as it was slowing down nearing a stop; I was in the station and there was a very very loud BANG the instant the descending tone switched to the final continuous drive tone; which I thought was most interesting. Within about a minute half the station was full of a thick, white yet nearly odorless smoke. I figured that transistor based drive and maybe some motor coil had met it's 1000 volts of instant DC death. Regarding the advancement of transistors, it seems the same thing is true for other types of motors. I work with old video tape machines and have noticed some very interesting and sometimes complicated methods of getting tapes to run at high (yet servo controlled) search speeds in the more expensive machines. I think I am hearing about 200 Hz as the maximum the coil switching speed in some of these capstan motors with parts originally designed in the early 1980's. When the machine is commanded to run at a slightly faster search speed the capstan motor just disengages and the machine switches to servo control of the direct drive dc reel motors (on some older machines). I'm guessing that is a duty cycle of less then 400 hz or so.

Brilliant video! I’ve had a slight grasp of the idea of pulsing (I’m a tram driver, and we have gone from resistors to transistors (still DC, two types) to AC technology. The DC I understood, but have never had the AC principle explained so easily. However: Early single-phase electrificiation used low frequency AC. The Thamshavn-Løkken Railway uses 25 Hz, and the Norwegian/Swedish/German railways uses 16 2/3 Hz. I’ve been told they use DC motors somehow converted to AC, and the low phase prevents arcing (they are still using brushes and coiled rotors). 50 Hz could not be used until transistors came along, before then they used converters (rectifiers), such as the Ignitron (a kind of mercury arc rectifier), before reliable solid state rectifiers came along. Details about this are in the book "The history of the electric locomotive" by F. J. G. Haut (aviable in libraries and on Amazon). For which reason many railways electrified with direct current (France, Belgium, The Netherlands). More detalis are to be found in the book "Electric traction on railwas" by Philp Dawson, but this is a rather old and rare book. Keep up the good work! :D

Thank you very much indeed for posting this extremely interesting video. In it you explain exactly what I've been wanting to understand for ages; plus a lot more besides !! My own favourite sounds are those of the German ICE model 3 (and the improved Velaro D), together with some of the London Underground trains.

Now I know why trains make the noises that they do. Remember those double deck train in the netherlands from your amsterdam video's? They have a characteristic woop-woop sound that's a bit like the examples you've shown. The really old (now out of service) mat 64 trains from the 1960's had some characteristic sounds, they accalerated quickly but could also break quite fast making a sound that I've associated with the sound of waterfall. These trains also made you feel every shock of the rails like those old prague trains. Those Mat 64 trains where awsome.

Back when I was studying Electrical Engineering at college, we spent months on DC motor drives, I still prefer Motor Generator sets rather than modern static converters, you can see and hear real engineering. Unstable electronics no thank you, give me the logic of a few thousand relays any day :)

Thanks Ben! Very informative!

Most interesting video I've seen in a while. Keep up good work!

I started going down this rabbit hole after riding Helsinki metro trains from late 70s/ early 80s. Learned they were apparently the first trains ever to use this technology and it’s really loud and very obvious compared to 90s trains. I really thought they had a gear box or something!

I have heard that sound on few modern trains too.

Excellent! Very clear explanation

fab video beno! I am still quite partial to the clunky clunk and the feeling of resistor banks tho!

This is interesting I'd always wondered exactly what caused the step change pattern of sounds as electric vehicles accelerate, knowing that they don't feature gearing systems like combustion drives I assumed it had to be something on the input side of the drive motor but never really knew exactly what.

I recently started riding the Metra Electric into Chicago and I’ve been really curious about this. Thank you sir 🫡

Thank you for making this - it is so underrated despite its importance, because even I have missed this video this first time round. If you have the time, are you able to make a video comparing how much power consumption is saved/used relative to each generation of technology used on trains (resistor - chopper - thyristor - GTO - IGBT - MOSFET)?

Great video, learnt a lot, thank you.

Effing brilliant 🙌🏽

I guess that's why you can reduce that frequency to make lifts sound nice.

I like the 1996 stock and class 450 also 444 and beno is smart

Great video. ☺️

The technologies of which you speak were actually available a bit earlier. I remember reading in Robert Tufnell's _The Illustrated Encyclopedia of Railway Locomotives_ that some experimental German diesel-electric locomotive had AC propulsion in 1968 (I might be off by a year in either direction), and that French trains started using synchronous AC motors in the 1970s. Meanwhile, in my own experience not relying on 3rd party sources, the Boeing USSLRVs (often just called LRVs) used on the MBTA (Boston area, USA) and MUNI (San Francisco, USA) in the 1970s had electronic choppers that went up to 400 Hz, but were NOT constant-frequency when starting up; they also had a low voltage generator that had a lower frequency chopper, with the total result that they sounded like they were powered by tortured ghosts with terminal indigestion. They did have a provision for switching out the propulsion chopper once they got going fast enough. I have seen one unit (in a 2 car train) on which this mechanism was broken on one end so that the chopper was always cut out, and so full voltage was applied to the motor (each end had 1 motor for 2 axles) when starting; but contrary to your expectation, it didn't destroy the motor or even trip a circuit breaker, but instead spun the wheels on that end (with great slippage); likewise, during application of reverse voltage during dynamic braking, it spun the wheels on that end backwards. The 1980s-vintage Hiticha trains on the east-west line of MARTA (Atlanta, GA, USA) had the same electrical systems (both propulsion and low voltage power supply), resulting in the same sounds, although much muted due to better sound insulation on these cars (this disappeared after they were rebuilt with modern electrical systems in the late 2000s/early 2010s). The MBTA (Boston area) Type 7s (built by Kinki-Sharyo) of the 1980s were actually a technological step back from the Boeing cars -- they had constant-frequency choppers operating at 220 Hz that never cut out, and they went back to a motor-generator for the low voltage power supply, whose hum could get very loud if the bearings were going bad; these were also a weak point in that they could fail (probably because somebody forgot to change the motor brushes), and then the train would soon after become disabled once the low voltage battery discharged below a certain point (which didn't take very long). Edit: By the way, fixed-frequency AC motors have been used for traction, and still are, although now to a limited extent. Pioneering examples entering actual revenue service include the FS (Italian Railways) E550 and their successors using 2 wire 3 phase supply, and the original locomotives of the Virginian Railway (EL-C) and the Norfolk and Western that used single phase supply but used a rotary phase convert to make the polyphase electrical supply for the motors (I think these came even before Kalman Kando did the same thing in Hungary). Modern examples in revenue service include the Petit train de la Rhune (in France) and up to 3 other mountain railways (but I am not sure which of the others still actually feed fixed frequency AC to the motors as opposed to rectifying the input 3 phase current and then re-inverting it to make variable-frequency AC). Presumably these dealt with the problem of poor starting torque by using over-engineered motors, as well as liquid resistors ro limit current to keep the wheels from slipping and prevent overheating of the motors.

Thanks for the great video! In the last section, what time did the switching occur? 14:59 ? (when high freq sound can't be heared?)

Thanks, I think this is the only video that mentions anything about unusual traction sounds. Siemens did a bang up job with the VF drives on the Taurus locomotive, that plays a musical scale when moving off. Interestingly, the class 700 trains recently introduced make a really weird car alarm type sound when running off the middle rail, but a normal sound when running from overhead, I don't know if that just because they're using two entirely different and separate VF drives or what.

Hey ben, what video editor do u use to edit your videos?

I like the sounds of these trains

Interesting question - how do Junipers make that thrashy sound? I hear it every time I’m on a 334 sat in the back of the front coach or vice versa.

It isn't really fair to say that Direct Current motors themselves are SO much less efficient than a VFD and induction motor. A bit less efficient, perhaps, yes, but not dramatically so. Using resistors to control the DC motors IS terribly inefficient, as noted. The real advantage of the AC motor and VFD is the elimination of the maintenance of the brushes and commutator. I am and will always be partial to direct current machinery, and so am quick to point out that it actually isn't so bad as is assumed JUST because it's "old". BTW, speaking of that, you didn't mention the original way that Direct Current power for traction was obtained from Alternating Current supplies: Rotary Converters! There's a truly marvelous machine. ;)

Thanks maite.

Best train noises: 1996 Jubilee Line trains Class 323 trains Siemens Taurus ‘singing’ locomotive 1992 Central Line stock Berlin S-Bahn Class 481/2 trains

Have a look at a mercury arc rectifier, designed in 1902ish was a crude but well used way of converting ac to dc, the Manx electric railway used to use several

I wish one day that one person makes an electric car with 90s pulsing patterns.

Skytrain in Vancouvers Mark 1 UTDCs are very distinctively GTO as the LIM really make it loud..very distinctive 1985 tech…only start being retired this year.

7:46 you could do it using led lights the higher the faster there flash the lower the slower there flash I learnt this in radio communications course

Jubilee line train has the best sound with the southeastern 466 train they both sound similar.

This is the principle of a variable speed drive.

Can we use Frequency Modulation (FM) as in radios and digital synthesisers (I’m not sure) where a wave is used to modulate another(......I think) to control 3 phase AC motors, by having 3 Frequency modulators to control the 3 separate phases? If not, what is the reason behind this?

I'm sure many people think you're crazy. But you really know your sh*t! Thumbs-Up

After so long, I have finally found a video that clearly explains why trains make these sounds. I'm so grateful for this video, thank you so much for your hard work!! I do have a question though; where can I learn more about this? Or in other words, how did YOU learn about this? Electrical engineering college course? Many youtube videos? Trained at a job that deals with this? Again, thank you so much and I can't wait to hear your response.

Great Vid, why is it that the class 323s make so many different sounds just to get to 20 mph

So what you mentioned about the singular tone sound at the start being made by the transistors (6:42) makes sense to me. And it makes sense how you described the IGBTs and such, changing the pitch of the sound along with the motor/train speed itself. However what doesn't make sense to me is that some trains, such as, say the Alstom trains on the Washington metro (3000/6000 series) have only several constant pitches that change with the train speed, and no smooth variation at all - just jumping through pitches. Why would that be? Is that what you mentioned about IGBTs? Or is that the very last thing where you said it changes so there's no resonance?

Hey Beno! I might sound stupid but can we get this kind of sound from today's latest technology inverters like SiC MOSFET inverters? Though their switching frequency is extremely high, can we shape the sound like the 1990"s trains make with the help of some tweaking in the algorithm?

What explains the cooling fan noise on alstom trains such as 465s 1996, and 1995 stocks. They make the motor thrash sound really good

Singapore's C751A rolling stock (made in 2001-2) make a higher-pitched version of the '96 stock's sound; a difference I can think of is that the former uses 1.5kV DC from overhead wires instead. The newer C751C stock (made 2014-5) sound similar at lower speeds but at higher speeds sound more like the C830C stock (built at the same time & sounds like Amsterdam metro's M5 rolling stock) that runs on a different line that uses 750V DC from a 3rd rail instead

I like the 377 sound,313 and 1996 sound.

Is the the one you mention at the end, the one that sounds like a alarm going off.

Brilliant video Beno you should get a look at the new scotrails trains on the ENG line they sound amazing

So it's the coil whine? EM induced acoustic noise? The same 50 Hz hum that comes from the power substation?

This is a really good video, with excellent annotations and commentary but I noticed some misleading imprecisions : #1 (5:30) As the motor starts, resistors must be sequentially *removed,* not turned on ! #2 (6:46 - 12:06) The first semiconductor equipment used as a switch to "pulse" the current from DC to DC was the thyristor, not transistor. It is limited as you said by its "chopping" frequency. By the way, such electronic apparatus is better known as chopper circuit (chopper control). Also, its wide adoption in trains began in the 70's. The first train driven by a thyristor-chopper in my country (Belgium) dates from 1970 ! The thyristor kept being produced until the 90's, depending on the country, etc. Eventually, basic transistors could be used as switches in chopper circuits, allowing higher switching frequency, but I don't know a single train model with this configuration. There is the modernised tram T5C5K but it was equiped with next-generation IGBT-transistor in 2002 (thanks hu.wikipedia), thus having nothing to do with 80's' transistors. Finally, GTO-thyristors and IGBT-transistors were both created in the 90's, having even better efficiency and allowing the use of 3 phases AC motors, in the now famous and melodious VFD's. ^_^ Apart from that, your video is excellent to popularize those underknown concepts ! Note to people interested : the clip at 6:01 can be found here : watch?v=BbvdBA4jygI

frequency changer ❤

*intense train sound*

And 2 more things you forgot to mention here: Random width, as heard on the S stock during its carrier-based pulsing. Spread spectrum, as heard on the Class 395 _Javelin._

great video! my only confusion is, for example on the 2009 underground stock, why does the sound seem to have "overtones"?

whats the first part of the sound (0:02), the really harsh sound before it starts to accelerate and make the rising tones?

Favourite video. 323 is best. Beno an electrical engineer?

Oh... they're literally just oversized audio synthesizers you'd find in 80-90s game consoles :P

This is a brilliant video..and thank you for explaining how these changing frequency sounds are made..but could I ask..what exactly is making these Sounds? The electric motor ? Or the other electric equipment? And what exactly are these sounds , they are obviously something vibrating?

Sydney Trains traction systems are as it follows: K sets and V sets V1-V27: Mitsubishi Electric camshaft resistance control, with DC series-wound motors V sets V28-V51 and T sets: Mitsubishi Electric GTO-4-quadrant chopper control, with 2-phase DC shunt-wound motors M sets: Alstom ONIX 1500 2-level IGBT-VVVF inverter control, with 3-phase AC induction motors H sets: Mitsubishi Electric 2-level IGBT-VVVF inverter control, with 3-phase AC induction motors A & B sets: Hitachi 2-level IGBT-VVVF inverter control, with 3-phase AC induction motors The Sydney Metro uses Alstom OPTONIX 2-level IGBT-VVVF inverter control, with 3-phase AC induction motors

My best friend thinks that the Jubilee Line Motor sounds like a dead cat.

If you hear the C751A and C751C motor sound, it sounds 'melodic' to you

6:00 sound like hanging or camshaft

So what I understand from the transistor explanation at 6:46 is that the dutch ICM(m) has 2 types of transistors and then switches over?

12:20 So the rate of the transistors is really easy to hear the 96 and 92 stock have lower frequency sounding ones. I need to watch the video again to properly understand it though. From a very brief overview though it seems like the more modern motors do a similar thing to the older dc motors but in a much more precise and controlled way or a way that allows the motors to work the way they do more naturally, if that even makes sense.

Apart from being AC and DC, why does an AC desiro (350\360) make slightly different noises to a DC desiro (444\450) Do you know how 1995 stock motors work?

What about the Metrowoagonmash 81-718/719 in the Kharkiv Metro on the Oleksiivska line (green line)? I know they have the DC pulsing, but they don't sound the same as the 1996 Stock on the London Underground.

Impossible how the 96 stock sounds were made by accident

1::::2:::3::4:5:4::3:::2::::1:::::1::::3::5::3::::1:::::1:::3:5:3:::1 Have you heard a class 73 electrodiesel in electric mode. It takes a DC input, but sounds like it has VF, even though it was built in the 1960s.

Great explanation, but my only criticism is maybe just slow down the explanation a little bit, it becomes kind of hard to follow you at some points.

Does Porsche Taycan also using this? Because the artificial sound is actually not artificial and it was an "futurized" recording of the motor sound, and the spaceship sound is similar to trains with VVVF

You can convert ac to dc like the charger in your phone some are switching chargers I uster teach this a lot its like my alarm clock it plugs into ac in wall and converts it to 12 v dc. You can get a dc to ac converter circuit

The 377s do that pulse sound around 32 mph on dc and 36-40mph and ac overhead wires, But that being said if it is just perfectionist programming that makes the motors sound .....a bit boring at the start ...and not a major benefit..then I'd much rather than switch it back to the way it used to be in the 90s

HELLO ?! Come on Beno, how risky would it be for you to tell me why some inner doors sound like they sound ? (I'm a lift surfer and urban explorer too just to remember you and I know that doing some things might put me at risk whilst others not much so).

Electric vehicles whine as well :)

may i ask if someone wants to put the inverter from the 1996 stock to the 1995 stock will it make the exact same sound?

Why aren't they programed like the 323

I have a diode bridge somewhere as on 9:27

And then there's SiC

Ever heard the Dutch VIRM trains?

Why class 456s has silent motors ?

But why does the 1995 train, its very similar cousin, not make that sound even though it’s slightly older, it sounds like it has a newer VF

Why do some inner lift doors sound like an IV line machine then ?

So, did anyone ever put thyratrons on a train?

At the start the train sounds like a networker

Sounds similar to the Siemens p2000 used in Los Angeles

I have no idea what half of this means; I just wanted to know why trains make the "rrreeeeeeererrrrrrr" noises when they pull off or slow down. Came away knowing a lot more than that.

I've done electronics engineering

I miss keikyu gto vvvf

If it’s due to the tech at the time, why does the 1996 stock pulse when the older 1995 stock doesn’t?

In Czech republic we have a train called city elephant (Actual name; not translated). It makes the CLEANEST "electric train sounds"

Why do new trains make the arching like sound before accelerating. The S stock and some adventras.

what makes that electrical 'tick... tick' sound that large diesel electric freight trains make when they are running but not moving my guess is that even at idle its generating electricity, and it has to go somewhere so every once in a while a relay goes off and somewhere a spark is created to dissipate the electricity? idk lol

I assume it was easier to change frequencies smoothly rather than pulse width.

Why was this re-uploaded twice