[KipFox]

Never mind the heat, the magnetic fields should be enough to keep your dac away.


JC

Fair enough, appreciate the input

 

[strider1007]

@KipFox said: "Question for current owners:
Does the left side that isn't vented on the MJ3 get toasty to point that you shouldn't put a small dac atop that area or would it be ok?"



That part of the topplate only gets luke-warm. Just make sure to not cover the MJ3's top vents and you'll be okay. Just as long as that dac isn't too hot itself..

 

[BassicScience]

Right, the "vast majority" of class D amps are simply not even worth considering when Hypex and Purifi designs are so demonstrably superior, and at very reasonable prices in the realm of high-end audio.

The Purifi designs have in fact been measured and proven to have load invariant frequency responses by ASR and others, so clearly the issue can be made to go away and doesn't require a "known load impedance", as you state above. You are correct in that these measurements have typically been done in the range of 1-16 ohms, and I have just fired off an email to Purifi asking for clarification on whether the results would theoretically be the same for load impedances in the range of 20-155 ohms (i.e., popular planars), as well as whether that has actually been measured in practice. With Purifi's permission, I will be happy to post whatever information I receive........ somewhere (not sure how this discussion ended up in this thread, actually).

 

[De7mi]

Right, the "vast majority" of class D amps are simply not even worth considering when Hypex and Purifi designs are so demonstrably superior, and at very reasonable prices in the realm of high-end audio.


The Purifi designs have in fact been measured and proven to have load invariant frequency responses by ASR and others, so clearly the issue can be made to go away and doesn't require a "known load impedance", as you state above. You are correct in that these measurements have typically been done in the range of 1-16 ohms, and I have just fired off an email to Purifi asking for clarification on whether the results would theoretically be the same for load impedances in the range of 20-155 ohms (i.e., popular planars), as well as whether that has actually been measured in practice. With Purifi's permission, I will be happy to post whatever information I receive........ somewhere (not sure how this discussion ended up in this thread, actually).

It’s gonna be very helpful to post the reply you get in the Tungsten thread as a lot of people there are looking to get a speaker amp for that headphone and Class D was a consideration. Thank you for doing this!

 

[GoldenSound]

Yeah if it turns out the purifi stuff will work for those impedance that'll be nice. There are some pretty affordable purifi/ncore options.

Not as cheap as the fosi stuff but still

 

[OhmsClaw]

@KipFox said: "Question for current owners:
Does the left side that isn't vented on the MJ3 get toasty to point that you shouldn't put a small dac atop that area or would it be ok?"



That part of the topplate only gets luke-warm. Just make sure to not cover the MJ3's top vents and you'll be okay. Just as long as that dac isn't too hot itself..

@KipFox having the Valhalla 2 and tested the MJ3 a couple weeks ago, the chassis both get toasty while the vent in question would be very uncomfortable to hold your hand over for any time. The heat sink will burn you if left in contact.

Just don't stack . Its a large amp anyhow, I know getting longer IC's for side by side may be annoying whether above/below or side-by-side + real-estate considerations on the desk/rack.

 

[rsmithor]

Too hot in the kitchen… an ultra quiet fan serves the Schiit MJ3 well. Running cool to the touch… I've left MJ running for days at a time.
— RS

 

[helloh3adfi]

How do you guys burn in your Mjolnir 3? Does it matter if I use the balanced XLR headphone output or SE output?

I'm waiting for my MJ3 to arrive whenever shipment is.

Looking forward to your comparisons to Rag2. MJ3 is more compact and probably needs less electricity.

 

[devilboy]

How do you guys burn in your Mjolnir 3? Does it matter if I use the balanced XLR headphone output or SE output?


Looking forward to your comparisons to Rag2. MJ3 is more compact and probably needs less electricity.

Will do.
Yes the MJ3 will use more. I'm ready for that. Some people say it gets really hot some people say it gets somewhat warm. I'm interested to see which it is. Doesn't matter though. If the MJ3 can have the control, speed and weight of the Rag 2 then I will be very happy.

 

[Rayski]

Will do.
Yes the MJ3 will use more. I'm ready for that. Some people say it gets really hot some people say it gets somewhat warm. I'm interested to see which it is. Doesn't matter though. If the MJ3 can have the control, speed and weight of the Rag 2 then I will be very happy.

I've been using eh MJ3 for over a month now (absolutely love it). I have it in a deep book shelf, closed back and only 6" high of clearance before the shelf above it. I added four small rubber feet that lift is 5/8" higher to give the bottom room to move any heat. I don't find the MJ3 hot at all. It is a little warm to the touch, but I would not have a problem leaving my hand on it for an extended period of time. Unless my unit is a freak, I think the 'hot' MJ3 talk is over hyped.

 

[devilboy]

I've been using eh MJ3 for over a month now (absolutely love it). I have it in a deep book shelf, closed back and only 6" high of clearance before the shelf above it. I added four small rubber feet that lift is 5/8" higher to give the bottom room to move any heat. I don't find the MJ3 hot at all. It is a little warm to the touch, but I would not have a problem leaving my hand on it for an extended period of time. Unless my unit is a freak, I think the 'hot' MJ3 talk is over hyped.

In my understanding, you would be correct about the "hot" hype.
I will probably have it on IsoAcoustics feet.

 

[Monsieur Dionysos]

Guys I think I need a rag

I've been using eh MJ3 for over a month now (absolutely love it). I have it in a deep book shelf, closed back and only 6" high of clearance before the shelf above it. I added four small rubber feet that lift is 5/8" higher to give the bottom room to move any heat. I don't find the MJ3 hot at all. It is a little warm to the touch, but I would not have a problem leaving my hand on it for an extended period of time. Unless my unit is a freak, I think the 'hot' MJ3 talk is over hyped.

Mine gets verry warm to the touch and the grills get so hot that I can only touch them for like 1sec without burning myself.

 

[joshua1122]

I have a 12V computer case fan sitting on top of the heatsink opening (pointing up), running at 5V (USB). Almost entirely noiseless at that speed on a Noctua 120mm. Aside from aesthetics, it fits like it was meant to be there, and it keeps the entire chassis a pleasant cool-warm at most (in a 72F room). Although I'm not sure how hot the amp needs to get to sound its best... I hope that cooling it isn't preventing it from reaching there. I want to add a PWM fan controller to slow it down a tad, because I don't need it to get that cool.

 

[helloh3adfi]

The rag2 does consume up to 500W electricity while Mjolnir 3 only up to 50W according to the spec sheets?

I have a 12V computer case fan sitting on top of the heatsink opening (pointing up), running at 5V (USB). Almost entirely noiseless at that speed on a Noctua 120mm. Aside from aesthetics, it fits like it was meant to be there, and it keeps the entire chassis a pleasant cool-warm at most (in a 72F room). Although I'm not sure how hot the amp needs to get to sound its best... I hope that cooling it isn't preventing it from reaching there. I want to add a PWM fan controller to slow it down a tad, because I don't need it to get that cool.

So your fan is blowing the air out of your Mjolnir? Did you place the fan inside the chassis?

 

[joshua1122]

So your fan is blowing the air out of your Mjolnir?

Yeah, it enhances the convection flow of heat, so the unit remains pretty cool to the touch all day long. 73F desk surface as measured by an infrared thermometer, and an even 80.2-80.3F over the entire surface of the MJ3.