[tomchr]

  If someone sends a Magni2 to Tom, I'm sure he'd be happy to measure it when time allows.
 
I should reiterate right now that the side-by-side measurement charts were compiled by me. Tom makes no mention of any of his work when discussing the measurements of the O2. He has also posted a small addendum by JDS Labs and amended portions of his text to reflect that.

 
You bet. I'll be happy to measure the Magni2 or any other product that makes for a good comparison with the HP-1. I'll have a pretty darn open schedule from mid April to early September, so that would be a good time. I do the work. You pay the shipping.
 
I can obviously easily be accused of bias. I would also point out that I am a human being (this fact has been independently verified), thus, suffer from the same cognitive biases as every other human being. That said, in my evaluations of other products I do my best to be fair and base my arguments on science, engineering, and measurements. I am not here to rag on anybody or any product. I understand NwAvGuy did that and while I didn't personally witness that, I have absolutely no intention of replicating that as that would reflect poorly on me and my business.
 
In case of the O2, I have provided all the data I took. Anyone can scroll through the plots without reading the text and draw their own conclusions. Should your conclusion be different than mine, that's fine. The text of the review is obviously my subjective opinion based on my interpretation of the data and my experience with the product. I do my best to keep my critique fair and science/engineering based.
 
I think there's one question floating around out there: Is the O2 worth the money? If you're a tinkerer who knows how to use a soldering iron but don't have any circuit design skills much beyond that, I think the O2 would be a fun project to tackle. There's plenty of options for tweaking. I mention the possibility of "rolling" opamps in my review, for example. If you, like I, have strong circuit design skills or want something higher end, I think you'd be better off putting your $120 towards another project.
 
If you do decide to buy an O2, I definitely recommend JDS Labs. They're rock solid.
 
Tom 

 

[mindbomb]

I thought the 50mw 300 ohm results for the o2 were pretty good. The 200mw 32 ohm results are not up to my standards, but I don't think people assumed a small amp like this could do that particularly well. I am surprised that there was no solidarity between ic amp designers, in this era where it seems fashionable for them to be looked down upon.

 

[Armaegis]

I'm one of those nutjobs who uses speaker amp monoblocks for his HE-6. I look down on anybody who doesn't have at least 40 lbs of iron on the desk

 

[SSSN]

 
You bet. I'll be happy to measure the Magni2 or any other product that makes for a good comparison with the HP-1. I'll have a pretty darn open schedule from mid April to early September, so that would be a good time. I do the work. You pay the shipping.
 
I can obviously easily be accused of bias. I would also point out that I am a human being (this fact has been independently verified), thus, suffer from the same cognitive biases as every other human being. That said, in my evaluations of other products I do my best to be fair and base my arguments on science, engineering, and measurements. I am not here to rag on anybody or any product. I understand NwAvGuy did that and while I didn't personally witness that, I have absolutely no intention of replicating that as that would reflect poorly on me and my business.
 
In case of the O2, I have provided all the data I took. Anyone can scroll through the plots without reading the text and draw their own conclusions. Should your conclusion be different than mine, that's fine. The text of the review is obviously my subjective opinion based on my interpretation of the data and my experience with the product. I do my best to keep my critique fair and science/engineering based.
 
I think there's one question floating around out there: Is the O2 worth the money? If you're a tinkerer who knows how to use a soldering iron but don't have any circuit design skills much beyond that, I think the O2 would be a fun project to tackle. There's plenty of options for tweaking. I mention the possibility of "rolling" opamps in my review, for example. If you, like I, have strong circuit design skills or want something higher end, I think you'd be better off putting your $120 towards another project.
 
If you do decide to buy an O2, I definitely recommend JDS Labs. They're rock solid.
 
Tom 

 


Thanks for the clarification, Tom.

Anyhow, NwAvGuy was strictly opposed to OpAmp rolling. Is there a chance you could do some measurements with different OpAmps? All we have is strongly subjective statements regarding different OpAmps in the O2.

 

[tomchr]

Thanks for the clarification, Tom.

Anyhow, NwAvGuy was strictly opposed to OpAmp rolling. Is there a chance you could do some measurements with different OpAmps? All we have is strongly subjective statements regarding different OpAmps in the O2.

 
While I do agree that measuring the O2 with other opamps would be interesting, I simply don't have the time. It took a good 2-3 days to take the data for the O2 and get them online. Doing that for every opamp out there is not feasible for me, in particular as I have plenty of paying work lined up. Sorry.
 
What I suggest is picking 2-3 opamp candidates and pouring over their data sheets. Look for things like high output current drive, low noise, and low THD.
 
Tom 

 

[tomchr]

HP-1 review: https://hearfidelity.com/reviews-1/neurochrome-hp-1

Tom

 

[tomchr]

The HP-1 looks rather stunning in its new wardrobe. Graphite grey. Steel top. Aluminum elsewhere. The steel adds a nice heft to the amp and adds some stiffness to the top plate.

Tom

 

[Armaegis]

When you say "top plate"... do you mean the face plate? Or is the main body/chassis now made of steel?

 

[tomchr]

By top plate I mean the top plate of the chassis. The plate on top with the ventilation holes. That plate is made of steel in the grey chassis. The front, rear, bottom, and two sides are aluminum.

Tom

 

[Armaegis]

Ooh!

I thought the top/sides/bottom were a single piece, hence my confusion.

 

[tomchr]

Per request many moons ago: Pictures of the HP-1 with better exposure to show the blue a bit more accurately.

Tom

 

[sp33ls]

Necro post, but just wanted to say that anyone who managed to obtain an HP-1 should consider themselves lucky. It's a superb piece of analog engineering.

And, in a world of Chi-Fi, it maintains a sense of pride in ownership. I enjoy the aesthetic of my Gundam HP-1.


I'd love to hear comments and impressions of any other HP-1 owners out there (an exclusive group, I know).