Why is Sonic Faster in America? NTSC vs PAL/60Hz vs 50Hz | Nostalgia Nerd


If you’ve ever been fortunate enough to play
Sonic the Hedgehog on a real life Sega Mega Drive (if you haven’t then get one off eBay
for about £15, there’s no excuse), then this will be familiar to you. This is how Sonic runs on 50Hz European equipment. It’s slow, it doesn’t feel quite right, but
to a UK bound kid back in the 90s, this is all we knew, this is how we thought Sonic
was meant to be. It’s kind of ironic that this blue character
who was supposed to be the personification of speed, just, wasn’t, over here. Fast forward a few years to emulation and
things seemed a little different, Sonic was less patience testing, the music was less
frustrating, the game felt fast, like a supersonic hedgehog should feel. But why was this? Did Sonic just speed up as he aged? Well no. The difference is, most emulators will run
as standard at 60Hz, this is what the Sega Genesis ran on, and the Japanese Mega Drive,
and it’s this frequency change which makes Sonic move quicker than we were used to over
in Europe. So what is this frequency? How does it weave into and affect our electronic
lives? It all goes back to the power supply. We discussed in my Clockspeed video how Hz
is a measurement of frequency; how many cycles or pulses in a given second. 100Hz equates to 100 pulses per second, whilst
1MHz equates to 1 million pulses per second, but rather than being driven by an oscillating
crystal as is common for computer clock speed, the original driver for electrical current
was the generator or turbine speed used to push the electricity out to the grid. Because we use alternating current, the polarity
of the electricity is switched many times a second, this has the nice side effect of
allowing transmission over long distances, and then if required, it can be converted
to DC back in the home. Back in 1891, Westinghouse Electric Company
had decided that because 60Hz produced less flicker with the arc light carbons in use
at the time, it was the best choice, and so that’s what spread throughout North America. Over in Germany, AEG Company had started using
40Hz, but noticed it created flicker on their lighting also. Upping to 50Hz seemed to eliminate this, and
so was chosen as their standard. This standard then spread throughout Europe. There were positives and negatives to each
choice, but we’re here to discuss Sonic rather than the details of mains frequency. Now you may be thinking… yeah, but the Mega
drive had a DC transformer, so current shouldn’t matter. Which is true, but we’re talking televisions
here, and European TVs were originally designed to accept signal input at 50Hz compared to
60Hz in the States. Televisions were designed so their vertical
synchronization rate, equated to the mains supply frequency; this helped prevent power
line hum and magnetic interference. So the difference meant screens over here
were refreshed at 50 frames per second, or 25 frames in reality, due to the bandwidth
limitations of the analogue PAL (Phase Altering Line) transmission. Whilst over in NTSC land (National Television
Standards Committee) signals refreshed 60 times per second, equating to 30 frames per
second given the same bandwidth limitations. These bandwidth limitations effectively meant
that only half the picture could be transmitted each second. But I’m not talking the top half was displayed
in second 1, followed by the bottom in second 2. That would create a somewhat disruptive viewing
experience. Instead the signal was interlaced meaning
on the first scan all the even lines are refreshed, followed by all the odd lines on the second. On PAL this happens 25 times for each set
resulting in a display of 50 interlaced lines per second, whilst for NTSC this equated to
30 frames per second or a refresh rate of 60 interlaced lines per second. So, derived from these early power supply
frequencies, this 60Hz display standardisation spread throughout the Americas, whilst 50Hz
spread through most of the remaining world. One interesting fact is that only half of
Japan uses a 60Hz mains supply. The reason for that is because AEG first supplied
50Hz generators for Tokyo and the Eastern regions in 1895, whilst America’s General
Electric supplied 60Hz generators for Osaka and the West. Through the use of transformers and frequency
converters, Japan has seemingly never felt the need to standardize this any further,
but given Japan’s adoption of the NTSC format all Japanese Mega Drives are designed to run
at 60Hz, with Japanese televisions adapted to compensate in 50Hz regions. So how does this affect Sonic. Well Sonic was created in Japan, and as consoles
at the time were designed to plug into the same inputs you’d receive TV signals through
they had to be converted to the appropriate format, and therefore were originally designed
to run at Japan’s 60Hz NTSC rate. When Sonic was released over in Europe, the
games’ coding was left unchanged from the code in the NTSC version, so if you play Sonic
over here in a European Mega Drive, 50 frames of action will be displayed to us for a given
second of game execution code, as opposed to 60 in other regions. Effectively this stretches out the gameplay
and leads to a 17% slowdown of the game… music, motion, responsiveness, the lot. This of course gives you more reaction time,
and makes the game somewhat easier, but the pace and action also feel a little more sedate,
almost as if they’ve been drugged. You may also notice that a larger border appears
around the game. Again this is an issue of standards, PAL has
a higher vertical resolution consisting of 625 vertical lines opposed to 525 for NTSC,
leading to a European Mega Drive outputting a resolution of 320×240 compared to the Genesis’s
320×224. To compensate for this extra unused space,
the Mega Drive dishes up a larger border, feeling more akin to the large over-scan borders
present on the Commodore 64 or Sinclair Spectrum. To get a real feeling for this, here’s a real
time comparison between the intro sequences of Sonic on both standards.You can really feel that 17% drop when you
compare them. Going back to PAL can initially feel like
a painful process, acceleration feels upsettingly slow, jumping feels like pushing through golden
syrup, waiting for a platform is like waiting for a village bus, not to mention the end
of level score tallying… and it’s not that the PAL Mega Drive couldn’t
handle putting out the increased number of frames, it’s just the PAL standard couldn’t
accept it, and therefore a standard European Mega Drive won’t allow it. It’s a bit like taking the standard game and
squeezing it through a bottle neck.. you’ll get all the gameplay, it’ll just take longer
to get it. If we simply slow down Genesis Sonic footage
by 17% we get exactly the same outcome. So the problem then, could be rectified in
the game’s coding. The standard Sonic engine is designed to output
it’s music and video at 60 frames per second. The PAL bottle neck built into the Mega Drive’s
VDU chip just forces it to slow down. If the Sonic engine had been written to recognise
a PAL region then the code timing could have been altered to push the same gameplay out
in 50 frames as opposed to 60, in effect actually making it lighter work for the Mega Drive
Hardware. A visual interpretation of this could be likened
to grabbing the Power Sneakers which throws the PAL version into double speed, equating
to 166% of the standard Genesis gameplay speed. But it’s not all bad news for PAL. We’ve already discussed that PAL has a higher
resolution, but it can also yield a higher fidelity image as every second line inverses
the phase of the colour signal. Any damage to the signal therefore comes out
as saturation discrepancies as opposed to hue issues on NTSC. PAL is also more effective at transmission
through bad weather, but unless you’re trying to transmit your Mega Drive’s RF output through
the airwaves, that’s really quite irrelevant today. These differences often led engineers to pun
NTSC as Never The Same Colour and PAL as Perfection at Last. In the UK we also had Scart plugs allowing
a much higher RGB picture quality than could be provided by coaxial cable, something North
America lacked. NTSC of course yields slightly more frames
per second, but the interlaced difference is barely perceivable to the human eye. Of course, it’s not just the Mega Drive this
affects. Whether it’s a NES, SNES, Master System or
any other international console. If the games weren’t coded and optimised to
also run in 50Hz (through coding and manipulation of gameplay timing variables, or frame skips
for example), then there would be differences. If you take a look at Sonic 2, the European
release was manipulated coding to bring the music up to NTSC speed, the game-play is also
slightly sped up, although not quite to NTSC levels (presumably accommodating for European
players being used to the slower Sonic 1 gameplay). Other games (especially European developed
ones) compensated for the switch completely – take Super Mario 3 on the NES – whilst conversely
a lot of Master System games were designed to run from the go at 50Hz due to the machines
popularity in Europe. In some of these cases, if you try and run
the game on a US system, you’ll potentially get a game which is too fast to be playable,
such as Bubble Bobble or The New Zealand Story. One thing to note is that sometimes there
are separate releases optimised for PAL or for NTSC, so slotting an NTSC optimised cart
into your 50Hz Master System will still make the game run slow and vice versa. With the arrival of digital TV and the ability
of modern LCD’s to run both NTSC and PAL, you might think that you could just hook up
your UK Mega Drive to an LCD and play at NTSC speed nowdays. However, this isn’t quite the case. Although the TV standard is the underlying
cause, the hardware built into the region dependent consoles still has to be told to
output to those standards. That’s why you have to modify a UK console
to run at 60Hz and vice versa. So with that in mind, it feels appropriate
to quickly revisit clock speeds… a PAL Mega Drive console actually runs at a slightly
slower CPU clock speed compared to NTSC (7.61MHz vs 7.67MHz) – as do other machines ported
across to PAL. But why is that? Well, remember that oscillator crystal? That’s the master clock, the thing which regulates
all the components, and this crystal needs to cycle at different speeds to accommodate
for the differing colour encoding frequency on each television standard. NTSC requires a sub carrier frequency of roughly
3.579MHz, PAL is 4.433MHz. The Master clock in each machine is then a
multiplication factor of these frequencies. This frequency is multiplied by 15 to get
a clock speed of 53.69MHz for NTSC models and by 12 to get a clock speed of 53.203MHz
for PAL models. This master frequency can then be divided
to run all the components, including the video display unit responsible for the video signal
out. In the case of the Motorola 68000 CPU, the
divider is 7, equating to a CPU speed of 7.61MHz on PAL and 7.67MHz for NTSC. It’s effectively as close a match engineers
could get whilst retaining the colour encoding frequency. Because of this quirk, you can usually run
NTSC on an accommodating PAL screen without modifying the clock, but the image will be
black and white. There are region modifications to get around
this without changing the crystal whilst retaining colour, albeit with the slightly slower PAL
clock speed… But thankfully being less than 1% slower this
is barely noticeable in play, and it has little to do with the 17% slowdown caused by the
PAL television refresh standard. There’s also the option of using the RGB out
on region switchable consoles to display a PAL 60Hz mode, providing both colour and the
60Hz speed on modern TVs. I do love it when a plan comes together. It’s these little details which have always
plagued my mind in the 60hz vs 50hz debate, and I for one feel refreshed to have brushed
up my knowledge on this. So if you felt like I did, hopefully this
video has cleared up the same questions for you. Now all that’s left is to fire up the Fusion
emulator, flick the PAL switch and remember how Sonic used to be, before we knew about
all this technical malarkey, back in Christmas 1992. Thank you for watching this comparative video
of the 60hz vs 50hz debacle. I do hope you enjoyed it. Subscribe for more, share it, give it a thumbs
up, and then perhaps click one of these videos if you fancy some more nostalgic action. In any case, thank you incredibly so for watching,
and as always, have a good night.

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