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Jab-Tech vs. Petras low speed yates.... a deep look.

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nd4spdbh2

Member
Joined
Nov 15, 2005
Location
Camarillo, CA!
Preface

Well guys that's right I'm bringing this up yet again. My curiosity has caught the best of me and i have decided once and for all to have a look at some yates bought at the same time and manufactured very close together from both stores... Petras Tech Shop and Jab-Tech.

A coupla days ago i made a thread HERE Showing how some OPEN cornered low speed yates i bought from J-t a while back (~ 14months ago) had smaller 25mm motors, a common size found in 80mm fans. Turns out those fans had come from a bad batch and thus is why they had horid motor ticking issues. Our Jab-Tech rep "jabtek" here at ocf was kind enough to send me replacements... 2 closed cornered, and 1 open cornered D12SL-12 yate loons. Thanks man!

I also purchased 2 closed cornered D12SL-12's from petras tech shop, and received my petras and J-T yates as well as a Nexus D12SL-12 from IKIKUINTHENUTZ today in the mail, THANKS ANDY! it was like Christmas when i got home from classes.

Comparison


The nexus will not be directly compared as it is a "different fan" but i will put notes about it where applicable.

So i took my three boxes up stairs and proceeded to open them.

Proof of purchases (areas blacked out for security purposes / information not made to the public)

IMG_0594%20(Small).JPG


In total i had 5 new fans and one slightly used one (the nexus)... Before taking them apart i carefully listened to each one making note of their noise characteristics and anything out of the norm... I used a NON PWM power source to power the fans, as a PWM type current can sometimes make normal dc powered fans exhibit weird acoustics... All fans tested at the same voltage... we will get to the details later in the conclusion.

Top Side

As you can see in the picture below i have the petras fan on the left and the J-T fan on the right. At first glance there isn't much of a diff besides the sticker missing from the hub of the fan assembly on the petras fan also i noticed that the 3 wire leads from the fan are about 5 inches longer on the petras model than the J-T one. I will be comparing all closed cornered models for this.

IMG_0596.JPG


Bottom Side

In this picture every thing is lookin the same, we have 3 rounded spokes and 1 flat spoke for the wires. But If you look closely at where the green arrow is pointing you will notice something. The jab-tech fan has a very visible lip running that entire ring around the fan... the petras yate does not. and its not just the picture making this difference its a very real physical difference. Note- the Nexus has 3 triangle shaped spokes and one flat spoke for the wires.

IMG_0600.JPG


Production Dates

Now some may say - "well maybe these fans were made at very different times" ... they were made ~4 months apart which isn't much of a difference.

The 3 digit number on the sticker will tell you the month/year they were manufactured. The straight edge ones are from 2005/2006 and the round ones above are from Sept (ish) 2007.
Its actually year/month but we know what you ment as in that quote he was referring to my bad yate loons with a date code of 709 ... 2007 9th month (september) that i bought back in November of 2007.

Here are the yates from petras and j-t... all the yates from petras had the same 901 date code January 2009... and j-t's a 809 date code.... September 2008.

IMG_0602%20(Small).JPG


Hub and Blades

I also noted another coupla differences is at the hub and where the fan blades meet the hub. 1 - The petras hub corner is a nice rounded shape whereas the j-t hub is a hard corner with a slight bulge. 2 - The petras fan has a nice gusset where the blade meets the hub whereas the j-t fan does not. There is a gusset on the underside of the blade on the petras and the j-t fan, but both the topside and underside gusset on the petras fan is much bigger than the j-t fan's only underside gusset. (didn't see it necessary to take a pic of the underside of the blades) I will note that the nexus fan was very similar to the j-t fan in that it only had an underside gusset but it was the size of the petras gusset and not small like the J-T gusset, the nexus also had a rounded hub corner like the petras yate.

IMG_0599.JPG


Time To Take Em Apart!

Thats right it is time. I took all three fans apart, i was mainly looking for motor size as this might explain differences in acoustics. The fans are very simple to take apart, peel back the sticker pop the rubber seal, pop off the plastic clip and the blade assemble comes out.

Now if im reading mr jabtek's words right from this quote ...
Medium and High Speed have a larger 30mm (1 1/4" ish) motor .. If you want crack one open and I'll send you a replacement although you shouldn't break it just opening it up.
This means that the Low speeds should have a smaller 25mm motor.

Lets have a look see...... whats that, the nexus and petras both have the bigger 30mm motors, and the jabtech has a punny lil 25mm motor commonly found in 80mm fans... and yet they all have the same sleeve bearing size HMMMMMMMMMM

IMG_0608.JPG


Closeups of the motors.... The nexus and petras fans have literally identical 30mm motors, the only difference i noticed is that the nexus has 4 extra resistors before each coil to reduce the voltage fed to the coils thus reducing the speed of the fan and an extra capacitor or two... then we have the J-T fan that has a lil itty bitty 80mm motor. Also if you look closely at the iron cores of the nexus / petras fan you notice that the faces are notched and angled in the direction of the rotation of the fan, obviously to aim the magnetic field... this is non existent on the j-t fan.

IMG_0609.JPG


Acoustics


I told you i would get to the acoustics didnt i. Well its pretty simple... the nexus wins out of them all and its obvious why... it spins slower and has capacitors to smooth out the voltage fed to the coils... but this fan is not part of our explicit comparison.

The fans from petras sounded exactly the same when comparing them to eachother, as did all three of the jab tech fans when comparing all 3 jab techs to one another. The difference is when you compare a Petras yate, with a J-T yate. None of the fans had any bearing noise what so ever, and being that the overall blade design was essentially identical the only acoustic differences could come from the motors / hubs them self's.

The petras fans were very quiet... an almost inaudible soft clicking could be heard if you put your ear 6in away from the hub on the exhaust side but couldn't it was very hard to hear even at that close of a distance. This is not the same for the j-t fan. The j-t fan was much more clicky, more pingy in fact. The clicks were much more pronounced and able to be heard much further away. Its obvious the motor difference has something to do with this, and it also seems like the void that was created in the hub of the J-T fan to mount the smaller circle magnet produces an amplification / echoing effect of the clicking of the smaller motor.

Conclusion


It seems as though petras and jab-tech get their fans from different sources. Petras has repeatedly stated and confirmed that they get their yates from yate loon DIRECT... so where jab-tech gets them is anyone's guess, but one thing is for sure... j-t's fans are of a cheaper quality, using smaller 25mm motors, and poorer manufacturing processes as indicated by the differences in the hub, fan to hub connection, and frame. And this cheaper quality is very much apparent in the acoustics of the fan.

My ears and the pictures dont lie... The petras closed cornered yate is by far better... the petras yate takes the best from the super duper well respected for its quietness nexus fan and is produced for the cheap.

So in the end ill let you guys decided, do it your self buy a fan from j-t and petras and see which one you like the best... or simply look at my in depth analysis of these fans... alls i know is that petras will be the place i get yate loons from now on.

I would like to thank Andy (IKIKUINTHENUTZ) for sending out the nexus fan. And J-T for sending out replacements of my bad yates i bought 14 months ago.
 
Excellent write-up nd4spdbh2 :thup:

It's easy to see the difference in manufacturing quality between these two types of fans once you crack the tops.
 
Was gonna place an order with Jabtech too ... just decided to go with Petra's instead. Wonder what other cheap knock-offs they're selling. This could go further than just fans
 
well jabtechs yates cost a $2 or $3 less then petras.

if your going with eco fans then why not the cheapest price?

then again my only complaint with jabtech is shipping. petras seems to always beat jab for shipping. and that is why i have bought things from petra's recently.

if i order big i go jabtech otherwise petras for small stuff.
 
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Great thread nd4. Pretty interesting to see differences like that among fans.
 
For kicks I decided to take apart an old yate I have from Petras. Sorry for the crappy pics but you'll get the idea. Date code on them is 710, so I think that would be October of 2007. Still the big motor then too, the frame and hub doesn't have the harsh edges, and the blades have the gusset thingy too. In other words, nothing has changed.

Pics too. I just took these, that paper with 2/3/2009 written on was from, well, 2/3/2009

http://www.xtremesystems.org/forums/showpost.php?p=3665416&postcount=5

October 2007 Built fan From Petras have the large motor and guy says it's the same as what was described above of the 2009 Petras fan
 
Nicely done. Very unbiased and thorough investigation. I am sure that you have not concluded, but simply fueled the ongoing debate about Yate fans though.
 
You just had to go and do this. Right after it all seemed cleared up, the can of worms is open again. Right after I spent a full day tearing apart my tempest case with a dremel to mount an RX360 on top, and burying the Yates I just got from Jab-Tech.

Now I'm going to have to tear my rig apart to get at those fans so I can bust them open and compare them to the ones I got from Petras a few months ago. I did a once over of the fans when I got them, and thought they were identical, but your close inspection leaves me wondering.
 
You just had to go and do this. Right after it all seemed cleared up, the can of worms is open again. Right after I spent a full day tearing apart my tempest case with a dremel to mount an RX360 on top, and burying the Yates I just got from Jab-Tech.

Now I'm going to have to tear my rig apart to get at those fans so I can bust them open and compare them to the ones I got from Petras a few months ago. I did a once over of the fans when I got them, and thought they were identical, but your close inspection leaves me wondering.

its easy to determine if they have a smaller motor... just look at the gap between the fan blade's hub assembly and the frame if you see the magnet wrapping around the very outter edge its a bigger motor... if you see the outer rim then an inner plastic rim then the plastic its a smaller motor. and id be willing to bet the petras fans have a nice big motor and the J-T fans have a lil motor.

just take a look at the pictures of the fan blade assembly of the jt fan above... see how there's 2 plastic rings... its easy to spot with the fan together, you dont even have to take it apart.
 
I like buying from Petras more, you have sealed the deal on the fans. Like to hear from Jabtech to see what they say... You put this on XS Forums yet? Waiting to see hair fly!
 
My fears confirmed. The Jab-Tech fans are of the wussy variety. That's BS. How can they have the same model # and be completely different fans.

BTW, how did you remove the blade housing group from the motor? I destroyed one of my jab-tech fans trying to tear it apart. I succeeded, but it will live out the rest of it's life as an empty shell/fan shroud. Well, at least I know where to buy cheap fan shrouds now.
 
Has anyone contacted YL directly about this in the past? It could be that JT are selling knockoffs and not real YL since they don't buy it direct but through a middle man (and yet can sell it for cheaper than someone buying it direct)?
 
It could also be that Yate Loon themselves make a cheaper line and a more expensive line of the same model fan too. After all, Yate Loon isn't in the retail fan business but rather builds to order. And that can mean different motors and less expensive impeller designs like you have noted here. Yate Loon wouldn't be the only fan maker that builds to suit custom specifications. You can also find fans built to custom specs from Delta, Panasonic and Sanyo Denki (and I imagine most other fan manufacturers).

BTW, excellent job on the comparison, nd4spdbh2. You were objective in your comparisons and backed them up with facts and proof (the pictures).
 
nd4spdbh2,

If you are interested, and curious to see the insides of a older yateloon. I have a spare yateloon sitting in my drawer from October 2006, "610" If you want to take a look inside it, shoot me a PM on how to take a part the fan safely. I'll post up some pictures. I can't say ill do it soon, because finals week is coming up. But ill get to it when i can.

Great post!
 
Just to throw another monkey wrench in here. I have 120mm low speed yates that I ordered from Jab a week or so ago. These however are of the orange variety.






So, there are clearly a few differences. It appears to be the 30mm motor These were made a little over a year ago, so I'm not sure if thats what constitutes the change, but another thing that I thought was odd is that the blade shape seems to be different. These are straighter on the trailing edge and appear to be sharper all around. I, unfortunately, don't have any noise comparisons as I don't even have my system up yet.

Also note, I ruined the fan :p. haha
 
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