YiHi SX Mini M Class temperature regulated box mod

YiHi SX Mini M Class temperature regulated box mod

This week I take a look at the long awaited YiHi SX Mini M Class temperature regulated box mod, using the new YiHi SX350J regulated chipset with temperature control.

Hopefully you are all already familiar with the YiHi SX mini, but if not I reviewed it here, with an update covering the revised 510 pin here

So , now the SX350J chipset is finished and YiHi bring us the new YiHi SX Mini M Class. There are some physical changes to the device, and some big changes to the electronics.

YiHi SX Mini Class M

Boxed, and protected whilst in transport to you, in the same SX Mini packaging as before. Included in the box, with the device, is the user guide, warranty card (with authenticity serial number) and usb charging lead.

YiHi SX Mini Class M

You can see here that the external physical look of the YiHi SX Mini M Class is almost identical to their (now named) Class S model. There are a couple of aesthetic changes which we will discuss later

YiHi SX Mini Class M YiHi SX Mini Class M

Same ‘hand shape’ in the body, same logos and marking on it as well. The 510 has the improved (slotless) pin and adjustment range. 23mm diameter 510 plate, now with a cross vent (the previous was just a line vent) for atomisers that take air from the 510.

YiHi SX Mini Class M YiHi SX Mini Class M

The base has similar markings, revised for the M Class and SX350J but otherwise the same.
Same battery insertion/changing method, the slotted (for a coin) cap just screws out with ease.

YiHi SX Mini Class M

Same button layout with a nice large fire button, large display, up/down buttons and usb charging socket.

YiHi SX Mini Class M

The usb lead can also be used to update the device firmware.

YiHi SX Mini Class M

The coating to the device is now a smoother, higher finish quality. Previously the finish looked powder coated, now it looks almost enamelled.

YiHi SX Mini Class M

And, those sharp edges of the SX Mini are now gone on the YiHi SX Mini M Class. A light bevel smooths the edges out, making it far more comfortable in the hand.

YiHi SX Mini Class M

The display is large, and holds a mass of information. Output, usage, output volts, coil resistance, battery charge and temperature setting.
You also still have the same memories and output ‘performance’ (soft, standard, powerful and a new powerful plus) as before.

YiHi SX Mini Class M YiHi SX Mini Class M YiHi SX Mini Class MYiHi SX Mini Class M

There are the original menus and new menus for temperature regulation.
We can adjust the output in joules (or watts when not in temperature control mode), the desired maximum temperature (°C or °F) , the unit of temperature (C/F) and whether the device is in Power (normal) or Joule (temperature) modes.

YiHi SX Mini Class MYiHi SX Mini Class M

The usual host of safety features are included. Lock and unlock with a triple press. Check atomiser if it is open circuit (missing coil/atomiser). Protection from reversed battery polarity, short circuit, low resistance, low battery and overheating.

YiHi SX Mini Class M

Here we can see the improvement the the base edges, the M Class (above in the picture) has smoothed edges.

YiHi SX Mini Class M

Here we can see that improved finish to the c-frame (the M Class on the right) which is now a smoother coating.

YiHi SX Mini Class M

Above is the SX350J chipset that YiHi has created for the YiHi SX Mini M Class.
Below are the specifications for that chipset, and hence the YiHi SX Mini M Class specifications as well.

YiHi SX Mini Class M

Below we have a YiHi made YouTube video of the temperature control functions.

And here we have the very important setting of a new coil resistance, this has to be done each time a new device (only for temperature control) is installed.

So, opinions time…

Firstly Joules.
Joules are a measurement of work done, or of work to be done. A joule is one watt for one second. So, 50joules could be 5 watts for 10 seconds or 10 watts for 5 seconds or 50 watts for 1 second etc etc..
In the context of the YiHi SX Mini M Class, it appears that the J output (of the Joule mode/temperature control mode) is same as how we already think of watts on other devices.
Simply put, the more the joules on the YiHi SX Mini M Class the more the device attempts to output into your coil.

So, that dealt with. Is the device any good ?

Well, in the previous SX Mini, I had a couple of physical ‘complaints’. The 510 adjustment depth, which they revised and fixed, and the sharp corners on the base were uncomfortable.
The YiHi SX Mini M Class has a light bevel to the base edges, making it far far more comfortable in the hand. This is a big improvement.

They have also massively improved the quality and finish of the coatings to the device, specifically the c-frame part of the body.

The electronics inside the device are as reliable and flexible, as before, but with a lot of new features for the temperature control mode.

These temperature control features are very complete and work very well. We have the ability to use the device in ‘normal’ or ‘temperature controlled’ modes (YiHI call these ‘Power’ and ‘Joule’ mode respectively). We can have temperature measured in Celsius or Fahrenheit. We can adjust temperature setting over a 100-300°C, or 200-580°F, range.

The Ohms range of 0.08-3.0 is also good, and gives us the scope to build nickel coils with ease (and Kanthal ones when in Power mode).

The temperature regulation works, and it works well and reliably. I had no issues with dry hits or burnt cotton at all.

The vape when temperature regulated on the YiHi SX Mini M Class is good, it feels less ‘acrid’ than ‘normal’ vaping. I found that a dry throat/ dry mouth was far far less obvious when vaping with temperature regulated to 180°C, and still as much vapour produced as I was previously used to. Flavour wasn’t improved but, as the wick/coil remains clean for a lot lot longer, the quality of the flavour lasted longer. Coils and wicks also lasted longer, needed changing less frequently.

I found that I needed to set my output (whilst in Joule mode) a little higher than normal. This was only about 10% higher, but it seemed to warm the coil up better, more like I was used to.
I might, for example, find 20 watts (not temperature regulated) to work well on my Magma. With temperature regulation I found 22-24 joules was the setting I liked, else it took too long to ‘warm up’. The device still has the Soft/Standard/Powerful/Powerful-Plus settings, using Powerful setting (and 20J) also had the desired effect.

I was delighted that you can now use the up/down buttons (as well as the gravity sensor) in the menus. This is a welcome change and makes changing setting when using a dripper a lot easier.
I also liked the way the main screen tells you if you are changing memories or adjusting them (with ADJ , M1-M5 displayed clearly in the corner).

Overall the YiHi SX Mini M Class is excellent, I love using it and it will be my ‘device of choice’ for quite a while.

The YiHi SX Mini M Class will not only be in the original silver/grey (frame/body) and silver/black, but also new colours of silver/rose and black/silver.

The price for the new YiHi SX Mini M Class is $200/180€/£160.

More information is available from the YiHi website here Yihi SX Mini site
The site has also has an authenticity checker (via the warranty serial number) and the software/firmwares to upgrade the device with.
and their Facebook page here facebook

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28 thoughts on “YiHi SX Mini M Class temperature regulated box mod

  1. David Wright

    thanks for taking the Time to do a in depth but simple for me to understand. It’s given me more confidence to buy one.

    1. timbozero

      You are welcome David, thanks for the feedback, glad you liked it.

    2. Ahmad

      Please help me to do the best decision for buying sx mini or vtbox dna200? Need your help and review as soon as possible.
      Thank you

      1. timbozero

        Hello Ahmad, thank you for your question.
        I cannot give you an answer as your needs and mine will be different, but if it helps I would wait a little while for the new SX Mini ML to be launched (expected December) and consider that rather than the M Class.
        Otherwise, what do you vape and what is important to you in a device as those would be important factors in making this decision. Perhaps join the Facebook group (link in the side bar) and let me know your needs there, I will try to help you.

  2. Mosallam

    I need to ask you something, I just received my M class, and I’m getting dry hits before it tells me that the coil is dry.. I built a 0.2, 30G Ni200 dual coil on the Magma, and I tried different setting for the Joules and temperature.. And one time I held the fire button with the magma’s lid off to check if it’s going to stop when it becomes dry but it didn’t (the wick caught fire).. And idea what could I be missing or doing wrong?

    1. timbozero

      Hello Mosallam, yes you need to set the coil resistance on the SX Mini.
      When the coil is cold (room temperature) you need to press both the up and down buttons and hold them until it tells you the resistance is set.

      1. Mosallam

        Thanks for your reply Timbozero, I really appreciate that..
        I tried to set the coil resistance first, and I think it worked 🙂
        Found it in the manual too, and I felt embarrassed I asked in the first place..
        I’m still experimenting with the settings though..
        Would you tell me what’s the difference between the Joules and the Temperature..
        From what I understand, the Joules work the same way as the Watts, and the temp is how hot I want my coil to burn, but is there something like a chart or guideline I could work with, or is it a trial and error process?
        I still get dry hits when I up the temp (say 250C/392F), that’s normal?!

        1. timbozero

          You are welcome.
          Joules mode yes, think of it like watts on a normal mod.
          As for temperature, you want somewhere between 160 and 210 Celcius (in my opinion). Cotton starts to burn at 214, so 210 should be your max.
          I personally run at 190 Celcius for a cooler vape with a smooth taste, others tend to go for the 210 maximum for the clouds they like.
          Additionally, make sure all the connections are good (tight posts etc.), no touching coils and that you do the ‘set resistance’ first before any dry test fires etc. (as close to 20°C as you can, i.e. cold).

          1. Regimen628

            I vape at 232-260 degrees Celcius, it’s great for flavor.

          2. timbozero

            Perfectly fine for non-cotton builds. A little risky if you use cotton, cotton breaks down into harmful chemicals at anything above 214°C.

  3. Mosallam

    Thanks a lot for your help timbozer, I got temp control thing mastered now!!
    No more dry hits for me 😀
    I guess the problem was with the Ni200 I was using, I had the 30gauge spool, and it was very thin that it was hard to make decent coils with it, so I think the resistance was never set properly..
    Now that I’m using 26gauge, things are a lot better..

    You know why is it recommended to make the Ni200 coils with spaced wraps?!

    1. timbozero

      Glad to hear you got it sorted. The reason why you use spaced coils is because when the coil heats up a contact coil will ‘spread out’ a little (touching less in some places), and cause resistance changes that are not due to heat.

  4. Ian

    Nice review, ordered one this morning and came across this after as I tend to read up on devices when I’m waiting for one. I’ve been using a RDNA40 (small screen), for temp control which only has Fahrenheit so good to see the info in Celsius as it’s more what I’m used to generally. Out of curiosity what’s your favourite RBA/RTA on the mod with Ni200?

    1. timbozero

      I have really enjoyed using the Subtank Mini on it, I have (due to the new premade Ni and Ti heads) been using the Delta 2 recently as well which is also nice.

  5. Andrea

    Hey there I am really curious as to why I am getting a low resistance error on my sx mini. It was doing just fine and then all of a sudden I am getting this error.

    1. timbozero

      Could you post a picture of your coil ? OR at the least the specs of the build and atomiser it is in please ?

    2. Gerardo

      How you fix this error?

      1. timbozero

        Hello Gerado, there is a method to do a hard-reset on the device. You can hold down the power button as you insert the battery. Though I asked Andrea for a picture and build details because a build has to be within certain specs to work.

  6. hi.. i just want to ask… is it true, ni200 cant make it micro coil?

    1. timbozero

      you can make a micro/contact coil with ni200, but it is not advisable on temperature control. this is because the amount of contact of the coil will change as it heats up, and this screws up the temperature control feature.

  7. syerrrrrrrr

    How can i identify the originality of SX Mini M Plus?

    1. timbozero

      As far as I know, there is no M Plus.
      You can check serial numbers at http://www.yihisxminiid.com/index.htm website.
      If it was made before July 5th then the serial number is only on the warranty card (inside the envelope in lid of the box).
      If it a new one (after July 5th) then the serial number is also laser etched on the (c-frame of the) body.

  8. Angelo Lee

    I just like to ask why is it my sx is indicating “Dry coil” when i’m in joules mode? But still firing on watts mode
    thank you.

    1. timbozero

      Joules mode is a temperature mode, if the coil gets too hot for too long the device will assume there is not enough juice and display ‘Dry Coil’. When in watts mode the temperature sensing is disabled.

  9. Kevz

    Hey might be stupid ? But what’s the best battery for the sx mini m class..

    1. timbozero

      I would say that ‘best’ is rather a subjective term. Personally I am using Sony VTC batteries in mine, but I think those are in rare supply now. Samsung 25R batteries have a good reputation as well. Basically look for a 20amp battery from a reputable (i.e. you have heard of them, well known brand) manufacturer.

  10. fitri

    hello. how can i identify my warranty ? cuz at my mod doesnt show the serial number

    1. timbozero

      Hello Fitri, The mod itself doesn’t have a serial number on it. In the envelope they have a warranty card with a serial number on it and you use that to check the device on their website (link in the review).

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