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Mjolnir Audio Pure Bipolar - Opinion on internal pictures

pozz

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Not given today's product offerings for headphone amps. Easily get as much power as you need for a lot less dollars.

My opinion's informed but not expert.
 

3125b

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Since you can get SOTA performance for much less money - it is not.
Looks a bit DIY, no idea about the performance without any proper measurements.
 

amirm

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Hello Amir/Everyone,

I need someone to evaluate the internals of this amp to see what's going on. It is supposedly a very high quality build and I have no reason to doubt this.

Just wanted an expert opinion (if anything can be gleaned from these images). Does it look like it's worth $2100?

https://www.head-fi.org/threads/sold-mjolnir-audio-pure-bipolar.884912/

Thanks

Thomas
Definitely not worth $2,100. Or even $1,100. It is a clean build but the discrete implementation likely has lower performance than $100 headphones amps we have tested.

There is also a potential safety concern as I don't see in the pictures clearly that the anodization is removed for the safety chassis ground.
 
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Rthomas

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Hello everyone,

Apologies for the late reply and thanks for the responses.

I really wonder whether a beast like this amp would be distinguishable in a blind test from something like a THX 789 (my current amp)
 

andreasmaaan

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I really wonder whether a beast like this amp would be distinguishable in a blind test from something like a THX 789 (my current amp)

Only if there's a serious problem with it, would be my guess :)
 

maverickronin

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This is an electrostatic amplifier...It's a completely different kettle of fish.
 
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Rthomas

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No he makes stat amps using the same case but this is an amplifier for dynamic headphones....
 

A Surfer

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Clearly you are being given very clear feedback that it is not at all a good investment at anywhere near that price. Have you committed to the purchase already? If not you really should be looking at some alternatives that have been measured here and performed well.
 

maverickronin

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No he makes stat amps using the same case but this is an amplifier for dynamic headphones....

Oh, that's new. The Stax cable in the last photo make it a bit confusing.

We are spoiled for choice for normal headamps independently verified to have excellent performance so there's no need to wander off into uncharted territory like with 'stat amps.
 
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Rthomas

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Clearly you are being given very clear feedback that it is not at all a good investment at anywhere near that price. Have you committed to the purchase already? If not you really should be looking at some alternatives that have been measured here and performed well.

Yes, I know. A $100 Atom probably measures better but I find myself wondering if they would sound the same in a level matched blind test.....

And no I've not committed to the purchase. I'm quite happy with my THX 789 but I just wonder if there is any merit to these more ''exotic'' discrete designs.....
 

andreasmaaan

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And no I've not committed to the purchase. I'm quite happy with my THX 789 but I just wonder if there is any merit to these more ''exotic'' discrete designs.....

There are basically two possibilities:
  • they measure worse, but the degradation in performance remains below thresholds of audibility and they therefore sound no different
  • they measure so much worse that the additional distortion they produce is actually audible
In the latter case, you may or may not prefer the sound. However, there are much cheaper ways to introduce a small amount of desired distortion into the signal, and much more flexible/fine-tunable ways to do it.
 

FrantzM

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Yes, I know. A $100 Atom probably measures better but I find myself wondering if they would sound the same in a level matched blind test.....

And no I've not committed to the purchase. I'm quite happy with my THX 789 but I just wonder if there is any merit to these more ''exotic'' discrete designs.....
Rthomas ... run .. run ... this is not worth even wondering ... The reality is that if it is objectively superior , it is superior... you THX 789 is a far better amp and likely more reliable ... Stop wondering. Try to EQ your headphones there following Oratorio settings and adjust to your liking if you feel the need...
 

Wes

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only worth $2100 if it uses hand-doped, single crystal devices
 

Killingbeans

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SMT components look like being soldered by hand. Not a good sign for reliability.

Badly hand soldered. It doesn't take much experience to make it look a lot better. But even then, as you say, it would put too much stress on the components.

Somebody should tell this guy that a cheap toaster oven can be modified to do proper SMD soldering with a correct temperature curve.
 
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Rthomas

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Hello everyone,

Thanks to all for chiming in. The consensus on this issue is clear :D
 

A Surfer

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Beyond clear. There is absolutely no excuse or need for any headphone amplifier to be more than say $500. At that price point all of the internals and casework can be more than adequate to provide years of high quality power that is audibly transparent to the user.
 

Noendgamehere

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Hi there... This is my first post to this website and community. This is an old thread, but I couldn't resist responding. It will probably be my last post as I don't think it will be taken very well. But, this thread is insanely negative and without any real info or substance. Just negativity and a lot of conjecture. For those who are unfamiliar with this amp and Mjolnir Audio as a whole, it is the brain child of Birgir and Kevin Gilmore. Two of the most respected minds in the hobby and community. Both responsible for some of the best sounding amps you can either build (if you are a DIY'er, or buy). They give their time and their mindshare to the community, they provide their designs, and Mjolnir exists as a business solely designed around the idea of giving back. Frankly, they deserve better than what I read above.

The Pure BiPolar is a variant of the Dynalo design ethos which has produced the Susi Dynalo, Dynahi, Pure BiPolar and the CFA3. It is an extremely efficient amp that sounds amazing. All of these variants sound amazing. They are extremely clean, and musical; with incredible pacing and timing. If you want to see how this amp measures, and read a review, you just have to look. Bob Katz reviewed and measured it a few yrs back. Here is the link for those interested. https://www.stereophile.com/content/katzs-corner-episode-18-icelandic-wonder

His review is of both an electro-stat amp as well as the Pure BiPolar. It may not be agreed with, but at least it will provide those measurements folks above were seeking.

I respect everyone's opinions. But, the consensus on this amp is not clear. I'd take this amp over most amps out there. I have put my money into a CFA3. It is pure amplification bliss. I am personally looking for equipment that can take me to my musics center. Unravel the complexity, find the pocket and take me to the venue for a visceral experience.

I didn't write this because I want to disrespect the fundamentals of ASR or those who subscribe. I respect this website and those that use the information here to make sound purchasing decisions. I just don't feel this thread is productive. I am not an engineer, nor am I a scientist. I am a music lover who has spent the majority of my life seeing live shows. My experience with music and this hobby has led me to use my senses to guide my choices with my hard earned money and the equipment I choose. In no way do I feel my way is the right or only way...

2 cents from a dissenting opinion... I apologize for upsetting the apple cart with my first comment to this community. Thanks for listening.
 

brimble

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this thread is insanely negative and without any real info or substance.

I'm a good person to reply to this, because I'm a fan of Birgir as a person and as a headphone repairer and am predisposed to like his amplifiers (although I've never had or even seen one, so my personal experience ends there).

It seems clear to me that this thread has plenty of substance. Maybe it could be more polite.
 
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