Sanyo Denki San Ace 120 9G1212H101 38mm
Special thanks to "The Finisher" for sponsoring this fan..
NOISE LEVEL PER CFM
Relative to the yate medium baseline fan, it's a little worse at lower volts and improves at it ramps up. Relative to the two other 3000RPM 38mm fans, it's better by about 2-3dbA. So noise level is actually very good from a metering standpoint at high RPMs and is now leading the way from about 42CFM to 55CFM.
This is again where the sound meter fails to report the whole story, noise quality is simply not captured in noise level.
Relative to the yate loon and most 25mm fans, very poor below about 11 volts. It has a very pronounced motor tick that's fairly harsh in comparison with the smoother 25mm fans. I've heard that PWM will make a worthwhile improvement to this problem, but I'm testing voltage control here and the fan is very ticky at lower volts similar to most 38mm fans. Unfortunately I don't have a good 3pin PWM controller that I can operate without a computer, or I would do a comparison for you. At this point in being consistent with the previous fan ratings, I'm simply going to say keep it at 11V or above if you want smooth sound. I would not recommend undervolting much unless you can some how cover up the motor noise to smooth it out somehow.
If I compare the yate loon medium at 8V in one video window and pause it, then load this fan at 6V pause it. The noise level meter and anemometer have them producing roughly the same noise level and air flow performance level. Yet to my ear, the yate loon is far superior in noise quality. With the yate, I hear air movement, with the San Ace I hear a motor. Perhaps some folks prefer the motor sound
. Regardless, the videos are there for the end user to make their own judgements about noise quality.
I think the industrial build quality is worthy of note, these fans are built like a tank and of very high quality. I suspect that is why many folks seem to like them so much, they do make your typical 25mm fan feel like a cheap piece of plastic and there is something to be said about appreciating something of high industrial quality.
PPCS has these fans for $22.99, so the fan is in the "HIGH COST" category, but similar to many of the industrial grade fans, so not unheard of.
Very good noise level per CFM above 2500RPM, noise quality is poor below 11V but smooths out at higher voltage, cost is high, and build quality is excellent.
I'll give the fan a thumbs up for it's lower noise level at 12V compared to the other two ultra high speed fans.VIDEO LINK