Scythe 120mm fans have become the de facto choice for SPCR users in the know in recent months, particularly the Slip Stream series. The brand offers more 120mm fan lines than any other in the computer DIY market. We tackle the Slip Streams, Kama PWMs, and the Ultra Kazes in a massive Scythe-attack.
May 8, 2008 by Devon
Cooke & Lawrence
Lee
| Editor’s Note — May 10, 2008 Since the posting of this article, it has come to our attention that there is the possibility of data corruption having tainted the CFM measurements. We apologize for the possible errors, but note that the noise level and quality information — the real keys to selecting and using fans in a quiet PC — are not affected. We will update you on this matter as soon as possible. |
After developing a more consistent fan testing methodology and arduously
re-testing all the previous fans in our database, it is time to finally take
a look at some new 120mm fans. It has been nearly a year since our last fan
round-up, and the number of untested fans in our lab has accumulated to the
extent where they can no longer be ignored. Our previous round-ups revealed
some great fans by Nexus, Noctua, and Scythe. Today, we focus solely
on Scythe fans, as their product line is quite varied and frankly, because they
are the most popular among SPCR readers.
Our main goals are to determine how much air each fan moves, the noise it generates
while doing so, and the nature of its acoustics. Through our analysis, we will
try to determine which of Scythe’s fans has the best airflow-to-noise ratio
when undervolted to near inaudibility, i.e. the most efficient quiet fans. Scythe
is one of those few manufacturers that seems dedicated to making
fans with good acoustics, so we expect to see some quality fans emerge.
Although we do a complete set of objective measurements for both airflow and
noise, we always base our final recommendations on how a fan sounds subjectively.
Typically, there is not enough variance in the objective measurements alone to make clear
distinctions. We’ve always said what really counts is what we hear.
For users who are interested, a technical discussion of fan technologies
can be found in our article, Anatomy
of A Silent Fan. Users who want to know exactly how the fans were tested
should refer to our Fan Test Methology. The rest of you: Read on and pay attention! We hope you find our work
useful.
HOW TO USE THIS REVIEW
Each fan in this roundup has its own data table
and write-up that summarizes
what we learned about it. Use these to find specific information about the fan
you’re looking for. In addition, every fan is recorded according to our
standard Audio Recording techniques. These recordings can be used to make
A/B comparisons between fans to help illustrate the differences between them.
Recordings are comprised of alternating ambient noise and the fan running at
various speeds recorded at a distance of one meter.
As always, we recommend that you listen and compare the recordings in a specific
way. The green box below describes how we make our recordings and what you’re
supposed to do with them.
At the end of the roundup is a conclusion that summarizes the best and the
worst that we found. This is where to look if you just want to cut to the chase
and find out which fan we liked best.
| HOW TO LISTEN & COMPARE This recording was made The one meter recording More details about how we make these recordings can be found in our short article: Audio Recording Methods Revised. |
THE FANS
The following fans were included in the roundup:
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
The Conclusion can be found on page
6.
We would like to thank Scythe
as well as Vancouver computer retailers Anitec, and NCIX
for supplying the many Scythe fan samples.
Ambient noise at the time of testing was 18 dBA. This ambient level was the same for every test conducted for this review.
| Brand | Scythe | Power Rating | 0.16A |
| Manufacturer | Scythe | Airflow Rating | 12.38 ~ 52.71CFM |
| Model Number | DFS122512L-PWM | RPM Rating | 310(±200) ~ 1200rpm(±10%) |
| Retail Availability | Yes | Noise Rating | Immeasurable ~ 24.89 dBA |
| Bearing Type | Sleeve | Header Type | 4-pin PWM |
| Hub Size | 1.58″ | Starting Voltage | 7.2 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 1 |
| Weight | 140g | Variance Noted | N/A |
| Voltage | Noise | RPM | CFM |
| 12V | 23 dBA@1m | 1180 RPM | 33 CFM |
| 9V | 19 dBA@1m | 850 RPM | 21 CFM |
| @700 RPM (8.1V) | ~18 dBA@1m | 700 RPM | 18 CFM |
| @500 RPM (7.6V) | <18 dBA@1m | 500 RPM | 11 CFM |
| @20 CFM (8.6V) | ~18 dBA@1m | 780 RPM | 20 CFM |
Our first fan is the Scythe Kama PWM, their only 120mm fan with a 4-pin PWM
connector (they also have a 92mm model). It is also possibly the most important
fan in this roundup due to the smaller number of PWM fans on the market. Some modern motherboards
only provide fan control when used with PWM fans. While one
can undervolt a 3-pin fan through a variety of methods, having the fan speed
automatically adjust based on CPU or system temperature makes life a lot easier.
NOTE: We do not have a standard PWM fan speed controller for use in the lab, so comments here have to be limited to what we learned with our voltage controller. One result is that the fan’s speed was artificially limited to a much narrower than usual range. We are in the process of selecting a suitable PWM fan speed controller for the future fan tests.
The Kama PWM is visually unremarkable. It has a fairly average
hub size, seven large blades, and closed corners (not suitable for use with
Thermalright clips or fan isolators without modification). The spokes are rounded
to faciliate smoother airflow, but run almost parallel to the trailing edges of the fan blades, which will tend to produce tonal noise. This is in contrast to most of Scythe fans, whose struts are usually more or less perpendicular to the fan blade edges. The box comes with a molex adapter and simple
fan screws.
Our sample had a high starting voltage of 7.2V — it simply will not spin up. This is directly related to its PWM design. Aside from that, the fan performed
very well. At 9V, it produced 19 dBA and 21 CFM, placing it in very high on
our list, second only to the Nexus Real Silent case fan. At high speeds, it
growled a bit, but was very smooth otherwise. It also exhibited
a slight clicking, but this was only audible very close-up and dissapeared below
approximately 8.2V. During one test run, the fan began to chug at 9V — turning
the fan off and re-monting it seemed to fix it. This was probably an anomaly.
For those seeking a PWM fan, the Scythe Kama PWM is an excellent choice. It
has a narrow speed range with voltage control; it should have a much bigger range with PWM control. At full speed, it is a bit
too loud for a silent PC. It’s a good quality
sleeve bearing fan, eseesentially what we have come to expect from Scythe.
Noise Recording
- Scythe Kama PWM DFS122512L-PWM — 7.6V-8.1V-8.6V-9V-12V with
5s ambient between each level: One meter, at 20 CFM (8.6V)
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.53A |
| Manufacturer | Scythe | Airflow Rating | 110.31 CFM |
| Model Number | SY1225SL12SH | RPM Rating | 1,900 RPM |
| Retail Availability | Yes | Noise Rating | 37 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 1.41″ | Starting Voltage | 4.7 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 2 |
| Weight | 120g | Variance Noted | See below |
| Voltage | Noise | RPM | CFM |
| 12V | 39 dBA@1m | 1780 RPM | 79 CFM |
| 9V | 26 dBA@1m | 1340 RPM | 54 CFM |
| 7V | ~18 dBA@1m | 630 RPM | 21 CFM |
| 5V | <18 dBA@1m | 400 RPM | 12 CFM |
| @20 CFM (6.8V) | ~18 dBA@1m | 610 RPM | 20 CFM |
Next up, we have the Scythe Slip Stream Kaze Jyuni series. As with
the Kama Flow line, they are sleeve bearing fans, but with a very different
design. They have nine, fairly slim blades and spokes that curve in the opposite
direction.
The narrow hub size also maximizes the amount of air the blades can produce
while minimizing the size of the dead spot at the center where the motor sits.
The Slip Stream series comes in 5 different speeds ranging from 1900 to 500
RPM. All the Slip Streams include a molex adapter with RPM sensor (connected
to a separate 3-pin header) and open corners, making them convenient for use
on a CPU heatsink.
A key design element of the Slip Stream series is the geometry of the spokes. They are curved in such a way that at any point of the rotation arc, the edges of the blades meet each strut at only one point, in a near-perpendicular angle. This feature is designed to minimize tonal noise. It is not unique to the Slip Stream fans; they have been used on other fans in the past, but the design is not common. The only downside of these spokes is that the one which acts as a bridge for the wires is quite wide, and probably adds more turbulence noise than usual.
The SH (super high) model is a very high power fan, rated to draw 6.36W at
12V. At 12V it is very loud and whiney, but that was expected. It does however
undervolt very nicely, dropping down to 26 dBA at 9V and ~18 dBA at 7V, making
it inaudible at one meter in our lab. At 7V, it generated 21 CFM of airflow
at a slightly lower noise level than the Kama PWM fan. At lower speeds it
produced a bit of ticking. At close range, the overall motor noise was slightly
higher than the lower speed Slip Streams, but still very quiet. A second sample
exhibited some bearing chatter, possibly due to shipping or other damage. As
we had only two samples, we are unable to confirm whether it was damaged
or if the first sample was simply exceptional. We suspect the the “good”
sample is how it is supposed to sound, judging from how the other Slip Streams
sound.
The range of the SH variant, along with its ability to start up at 5V makes
it very versatile. It can be a super high performance fan if your CPU is cranking
away encoding video or and an almost silent one for when you’re just lazily
surfing the web.
Noise Recording
- Scythe Slip Stream SY122512SH — 5V-6.8V-7V-9V-12V with 5s ambient
between each level: One meter, at 20 CFM (6.8V)
JUMP TO:
- Introduction
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
- Conclusion
SCYTHE SLIP STREAM SY1225SL12H
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.41A |
| Manufacturer | Scythe | Airflow Rating | 88.11 CFM |
| Model Number | SY1225SL12H | RPM Rating | 1,600 RPM |
| Retail Availability | Yes | Noise Rating | 33 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 1.41″ | Starting Voltage | 4.2 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 6 |
| Weight | 120g | Variance Noted | None |
| Voltage | Noise | RPM | CFM |
| 12V | 32 dBA@1m | 1460 RPM | 61 CFM |
| 9V | 29 dBA@1m | 1250 RPM | 47 CFM |
| 7V | 24 dBA@1m | 1080 RPM | 40 CFM |
| 5V | 21 dBA@1m | 890 RPM | 30 CFM |
| 20 CFM test not conducted because fan stalled before slowing enough. | |||
The high speed Slip Stream had a smaller range of noise and airflow levels. It
never spun slow enough for use in a silent system. We were suprised that between
9V and 5V, it was significantly louder than the Super High speed variant.
Throughout its range, the noise of this fan was was smooth and fairly benign. At high speed there was a lot of turbulence, but relatively
little whine. It is a high quality fan, but it doesn’t
meet our standard of silent because it is not capable of running slowly enough.
The noise to airflow ratio was more or less the same as the Super High Slip
Stream. Undervolted to approximately the same noise level, they perform similarly.
Noise Recording
- Scythe Slip Stream SY1225SL12H — 5V-7V-9V-12V with 5s ambient
between each level: One meter
SCYTHE SLIP STREAM SY1225SL12M
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.26A |
| Manufacturer | Scythe | Airflow Rating | 68.54 CFM |
| Model Number | SY1225SL12M | RPM Rating | 1,200 RPM |
| Retail Availability | Yes | Noise Rating | 24 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 1.41″ | Starting Voltage | 2.4 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 4 |
| Weight | 120g | Variance Noted | None |
| Voltage | Noise | RPM | CFM |
| 12V | 28 dBA@1m | 1210 RPM | 46 CFM |
| 9V | 24 dBA@1m | 1030 RPM | 37 CFM |
| 7V | 21 dBA@1m | 890 RPM | 30 CFM |
| 5V | ~18 dBA@1m | 720 RPM | 24 CFM |
| @20 CFM (4.0V) | <18 dBA@1m | 620 RPM | 20 CFM |
The Medium speed Slip Stream is probably the most sensible choice among the five. It spins reasonably
fast at full speed and undervolts well, becoming effectively inaudible at 5V.
It also has a very low starting voltage of only 2.4V. What impressed us most
was how smooth and consistent the fan sounded, no matter what speed it
was running at. At high speeds, a typical sleeve bearing fan drones and whines,
and at low speeds it ticks or chatters. We listened very carefully for increasing
and decreasing bearing/motor noise as the speed was adjusted, and the difference
was minimal.
As for performance, well, it was simply the best. Of all the fans we’ve tested
at approximately 18-19 dBA, none could match the 24 CFM the Slip Stream M pushed,
not even our reference Nexus fan. Interestingly, according to various reports,
the Scythe Ninja Rev. B now ships with this exact fan model. Some heatsinks
do not even come with fans, so for Scythe to include their best fan with the
current Ninja gives us all sorts of warm and fuzzy feelings.
Noise Recording
- Scythe Slip Stream SY1225SL12M — 4V-5V-7V-9V-12V with 5s ambient
between each level: One meter, at 20 CFM (4.0V)
JUMP TO:
- Introduction
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
- Conclusion
SCYTHE SLIP STREAM SY1225SL12L
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.10A |
| Manufacturer | Scythe | Airflow Rating | 40.17 CFM |
| Model Number | SY1225SL12L | RPM Rating | 800 RPM |
| Retail Availability | Yes | Noise Rating | 10.7 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 1.41″ | Starting Voltage | 3.2 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 2 |
| Weight | 120g | Variance Noted | None |
| Voltage | Noise | RPM | CFM |
| 12V | 19 dBA@1m | 770 RPM | 24 CFM |
| 9V | ~18 dBA@1m | 640 RPM | 21 CFM |
| 7V | <18 dBA@1m | 540 RPM | 18 CFM |
| 5V | <18 dBA@1m | 420 RPM | 13 CFM |
| @20 CFM (8.4V) | ~18 dBA@1m | 620 RPM | 20 CFM |
The 800 RPM Slip Stream is also very impressive. For those who don’t want to
muck about with fan control, it can be run at full speed and be
inaudible in the majority of systems. It’s very quiet and can be made dead silent
with a bit of undervolting. Like the 1200 RPM model, it has a low starting voltage
and good acoustics across its range. Very smooth and quiet all the way up to
12V.
It did not quite match up to the Slip Stream M in performance, falling a few
CFM short, but basically tied the Nexus fan. Interestingly, a Slip Stream L
shipped with the Scythe Ninja Copper, and in our review, it performed better
than the Nexus fan by a couple of degrees.
Noise Recording
- Scythe Slip Stream SY1225SL12L — 5V-7V-8.4V-9V-12V with 5s ambient
between each level: One meter, at 20 CFM (8.4V)
SCYTHE SLIP STREAM SY1225SL12SL
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.07A |
| Manufacturer | Scythe | Airflow Rating | 24.5 CFM |
| Model Number | SY1225SL12SL | RPM Rating | 500 RPM |
| Retail Availability | Yes | Noise Rating | 7.5 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 1.41″ | Starting Voltage | 7.3 |
| Frame Size | 120 x 120 x 25 mm | Number of Samples | 6 |
| Weight | 120g | Variance Noted | See below |
| Voltage | Noise | RPM | CFM |
| 12V | <18 dBA@1m | 440 RPM | 14 CFM |
| 9V | <18 dBA@1m | 350 RPM | 10 CFM |
| 7V | <18 dBA@1m | 270 RPM | 6 CFM |
| 5V | <18 dBA@1m | 170 RPM | 2 CFM |
| @20 CFM (N/A) | N/A | N/A | N/A |
If 800 RPM is not low enough, Scythe also has a Slip Stream fan that spins
at a paltry 500 RPM. In all the but the most silent of systems, the SL seems
to be a pointless investment. Through its entire range, the noise level never
broke the ambient level in the room, as one would expect. It did however click
at low speeds, though why anyone would run it below 12V is a mystery. The SL
will be drowned out in anything but a passively cooled system.
There was some variance in our batch of samples, with some clicking more than
others. Unless there was something wrong with the shipment we received, buying
an SL model Slip Stream may be a bit of a crapshoot.
Noise Recording
- Scythe Slip Stream SY1225SL12SL — 5V-7V-9V-12V with 5s ambient
between each level: One meter
JUMP TO:
- Introduction
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
- Conclusion
SCYTHE ULTRA KAZE DFS123812H-3000
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.60A |
| Manufacturer | Scythe | Airflow Rating | 133.6 CFM |
| Model Number | DFS123812H-3000 | RPM Rating | 3,000 RPM |
| Retail Availability | Yes | Noise Rating | 45.9 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 2.17″ | Starting Voltage | 3.1 |
| Frame Size | 120 x 120 x 38mm | Number of Samples | 2 |
| Weight | 300g | Variance Noted | See below |
| Voltage | Noise | RPM | CFM |
| 12V | 47 dBA@1m | 2760 RPM | 107 CFM |
| 9V | 40 dBA@1m | 2180 RPM | 77 CFM |
| 7V | 34 dBA@1m | 1710 RPM | 56 CFM |
| 5V | 24 dBA@1m | 1160 RPM | 34 CFM |
| @20 CFM (3.6V) | 19 dBA@1m | 730 RPM | 20 CFM |
Scythe also carries a line of 38mm thick, high
performance fans. The Ultra Kazes come in three speeds: 3000, 2000, and 1000
RPM. The extra width allows for deeper fan blades, but with it comes increased
weight and a larger, more powerful motor — the hub size is more than two inches
across. A molex adapter with
RPM header is included. We highly recommend using the adapter as lower quality
fan headers may not be able to supply enough power and may burn out if used
in conjunction with this fan — especially the high speed variant. The spokes are curved exactly like the Like the Slip Stream series for acoustic benefits.
The 3000 RPM model is the loudest 120mm fan we’ve tested. Its acoustic quality is
poor, droning and buzzing at low speeds, and shaking and vibrating
at high speeds. It also clicks throughout its entire range and one of our samples
had an unpleasant resonant spike at 7V. It is nowhere close to our standards
for a silent fan, and unfortunately doesn’t offer any performance advantage
either.
It pushed less air than the Slip Stream 1200 RPM and 1600 RPM models while producing
the same level of noise (24 dBA) and it was the only fan that was unable to
output 20 CFM without overtaking the ambient noise level. Being so large, heavy,
and with poor acoustics, one would think it would at least perform more efficiently,
but it just wasn’t the case, at least for the H model. It may have something
to do with the unusually high weight. At 300g it is 70g heavier than the lower
speed Ultra Kazes.
One has to assume that the greater depth of the blades result in higher pressure, which would probably be useful in a high airflow impedance application like a heatsink with very tightly spaced fins. (We do not test for pressure currently.) However, this is not something we recommend, and most SPCR readers seek to minimize airflow impedance in order to enable good cooling with very slow fan speeds.
Noise Recording
- Scythe Ultra Kaze DFS123812H-3000— 3.6V-5V-7V-9V-12V with 5s
ambient between each level: One meter, at 20 CFM (3.6V)
SCYTHE ULTRA KAZE DFS123812L-2000
Ambient noise at the time of testing was 18 dBA.
| Brand | Scythe | Power Rating | 0.25A |
| Manufacturer | Scythe | Airflow Rating | 87.63 CFM |
| Model Number | DFS123812L-2000 | RPM Rating | 2,000 RPM |
| Retail Availability | Yes | Noise Rating | 32.91 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 2.17″ | Starting Voltage | 2.4 |
| Frame Size | 120 x 120 x 38mm | Number of Samples | 2 |
| Weight | 230g | Variance Noted | None |
| Voltage | Noise | RPM | CFM |
| 12V | 37 dBA@1m | 2030 RPM | 71 CFM |
| 9V | 32 dBA@1m | 1670 RPM | 53 CFM |
| 7V | 25 dBA@1m | 1380 RPM | 42 CFM |
| 5V | 20 dBA@1m | 1060 RPM | 29 CFM |
| @20 CFM (3.3V) | ~18 dBA@1m | 740 RPM | 20 CFM |
The L2000 Ultra Kaze 120 has characteristics similar to the H model but it is much less aggressive sounding. It exhibited a lot of drone, and some buzz. Despite being 1000 RPM slower than the H model, it could not be be described as quiet, even at 5V. Performance was more efficient compared to the
high speed model, but not as good as the Slip Streams.
Noise Recording
- Scythe Ultra Kaze DFS123812L-2000— 3.3V-5V-7V-9V-12V with 5s
ambient between each level: One meter, at 20 CFM (3.3V)
SCYTHE ULTRA KAZE DFS123812L-1000
| Brand | Scythe | Power Rating | 0.25A |
| Manufacturer | Scythe | Airflow Rating | 44.44 CFM |
| Model Number | DFS123812L-1000 | RPM Rating | 1,000 RPM |
| Retail Availability | Yes | Noise Rating | 19.81 dBA |
| Bearing Type | Sleeve | Header Type | 3-pin |
| Hub Size | 2.17″ | Starting Voltage | 3 |
| Frame Size | 120 x 120 x 38mm | Number of Samples | 3 |
| Weight | 220g | Variance Noted | None |
| Voltage | Noise | RPM | CFM |
| 12V | 20 dBA@1m | 1000 RPM | 27 CFM |
| 9V | ~18 dBA@1m | 780 RPM | 22 CFM |
| 7V | <18 dBA@1m | 610 RPM | 16 CFM |
| 5V | <18 dBA@1m | 440 RPM | 11 CFM |
| @20 CFM (8.3V) | ~18 dBA@1m | 720 RPM | 20 CFM |
The 1000 RPM model is similar to the other two in the Ultra Kaze series. The lower speed results
in less drone and buzz, but its acoustic character is still noticeably
poor even when undervolted to 5V and 18 dBA. Performance was very similar to
the 2000 RPM variant. It’s simply not quiet enough. There are
many, many alternatives that will provide the same airflow, but with much better
acoustics.
The Ultra Kaze line is disappointing. They are really only suitable for high
heat, high impedance situations where noise is not a factor.
Noise Recording
- Scythe Ultra Kaze DFS123812L-1000— 5V-7V-8.3V-9V-12V with 5s
ambient between each level: One
meter, at 20 CFM (3.3V)
JUMP TO:
- Introduction
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
- Conclusion
COMPARISONS
| Scythe 120mm Fans At Ambient Noise Level (~18 dBA@1m) | |||
| Model | Voltage | Fan Speed | Airflow |
| DFS122512L-PWM | 8.6V | 780 RPM | 20 CFM |
| SY1225SL12SH | 7V | 630 RPM | 21 CFM |
| SY1225SL12M | 5V | 720 RPM | 24 CFM |
| SY1225SL12L | 9V | 640 RPM | 21 CFM |
| DFS123812L-2000 | 3.3V | 740 RPM | 20 CFM |
| DFS123812L-1000 | 9V | 780 RPM | 22 CFM |
When set at the speed where the fan noise at one meter did not change the lab’s ambient SPL of 18 dBA, most of the fans performed similarly,
with one exception. The 1200 RPM Slip Stream M stood out, pushing more air than
all the other Scythe fans. As a bonus, was also the best sounding of the bunch
(along with the 800 RPM variant), making it the clear winner of all of Scythe’s
sleeve bearing fans, and the best performer to date.
While the 1000 and 2000 RPM Ultra Kazes performed well, the measured SPL is
deceiving. They sound subjectively worse than any of the other fans in the round-up
when registering ~18dBA@1m. The others are more or less inaudible.
CONCLUSIONS
Almost all the Scythe Slip Stream fans are winners, as is the Kama PWM fan. The
1200 RPM Slip Stream in particular performed amazingly, pushing more air at the ambient
noise level of our lab than any other. The 800 RPM Slip Stream L is also
formidable, matching the performance of the Nexus fan in our fan test setup,
and beating it for airflow and/or cooling when used with the Scythe Ninja Copper. It can
be run at full speed in most systems without being heard.
The larger, heavier Ultra Kazes did poorly in comparison.
While they move lots of air, the acoustic cost is unacceptable for silent PC enthusiasts. They are best used in high impedance loads, such as blowing air through tightly spaced watercooling radiators, but quiet operation is out of the question.
Some will want to argue that the sleeve bearings of these Scythe fans don’t hold up well under high heat conditions. It’s not as cut and dry as some folks would like you to think; there are complex factors in comparing ball bearing and sleeve bearing fan merits. (See Anatomy
of A Silent Fan for more details.) The bottom line is that the Nexus 120 we’ve been using as a reference is also a sleeve bearing fan, and we’ve not heard complaints about the shortness of their life in the many years that we’ve been recommending them.
Finally there’s the issue of price. Scythe Slip Stream fans typically sell in the US and Canada for no more than $10, sometimes as little as $8. This is a far cry from the $15~20 for a Nexus 120 or $18~25 for a Noctua 120. It’s not the bargain basement value price of $3~5 for a Yate Loon 120, but the Scythes are actually a bit quieter, packed for better protection in transit, and come with cable adapters. They will go, at least for now, to the top of SPCR’s fan rankings.
Great thanks to Scythe, Anitec and NCIX
for supplying the fan samples.
*
SPCR Articles of Related Interest:
Fan Test Methodology V.3
Testing Fan Airflow V.2
SPCR’s Fan Roundup #4: 120mm Fans
SPCR’s Fan Roundup #3: 92mm Fans
SPCR’s Fan Roundup #2: 120mm Fans
SPCR’s Fan Roundup #1: 80mm Fans
SPCR’s Fan Testing Methodology
Anatomy of the Silent Fan
SPCR’s Recommended Fans
* * *
Discuss
this article in the SPCR Forums.
* * *
JUMP TO:
- Introduction
- Scythe Kama PWM DFS122512L-PWM
- Scythe Slip Stream SY1225SL12SH
- Scythe Slip Stream SY1225SL12H
- Scythe Slip Stream SY1225SL12M
- Scythe Slip Stream SY1225SL12L
- Scythe Slip Stream SY1225SL12SL
- Scythe Ultra Kaze DFS123812H-3000
- Scythe Ultra Kaze DFS123812L-2000
- Scythe Ultra Kaze DFS123812L-1000
- Conclusion
