Review and Measurements of Neurochrome HP-1 High-Performance Amp

[Soniclife]

I'd like to take the opportunity to ask you folks here: If I was able to make a headphone amp available in a prettier case, with a volume knob that felt right, and that would provide the same performance (except likely lower output power) for around $500-600, would you be interested?

Or let's say I went the other way and wanted to make an amp for the $5-10k space. What features, performance, etc. would you expect?

This seems like the right question for manufacturers like yourself to be asking.

Things look very tough suddenly in the low power device market, with a growing collection of very high performance items coming from China. These items might not be SOTA but they are more than good enough for the job, which leaves very little room in the market at the lower reaches. There are still people who want exceptional performance, pride of ownership , luxury feel and longevity, and are prepared to pay for it, offering that, whilst still offering the DIY kits that ground the prices would be a unique offering. So my best guess is add up market to the range.

 

[JJB70]

I am sure I am missing lots of stuff in this whole knob brouhaha... but I have to admit it is some fun to see what I assume are mostly grown men so passionate about a knob... kind of reminds me of watching Zeos... now there is someone with serious issues with knobs. Anyway, I will sit back, watch, and eat some popcorn...

Believe it or not, Zeos's obsession with knobs (and ear pads) is one reason I enjoy his videos, that and the fact some of the stuff he say's makes me laugh I find that these days it's hard to find a DAC or amp that doesn't sound decent enough, but the feel of gear, the controls etc are often what sets equipment apart.

 

[Soniclife]

I must admit that the first time this was brought up with me, I'm pretty sure I developed some serious bruising from the face-palms. Then again, market says, "we want pretty knobs that feel right". It would behove me to listen rather than to argue.

My brain is wired in a similar way, but there is something about the tactile feel of controls that we respond to, look at the luxury car market, they put a lot of effort into making every small switch etc feel nice, they don't work any better I expect, but using them makes us feel better. I'm short we make dumb decisions about quality based on how something feels, and knowing the truth will do little to change our feelings.

 

[restorer-john]

I'm short we make dumb decisions about quality based on how something feels, and knowing the truth will do little to change our feelings.

You bought Apple gear huh?

 

[jsmiller58]

Believe it or not, Zeos's obsession with knobs (and ear pads) is one reason I enjoy his videos, that and the fact some of the stuff he say's makes me laugh I find that these days it's hard to find a DAC or amp that doesn't sound decent enough, but the feel of gear, the controls etc are often what sets equipment apart.

Sure, no problem, can understand! I thought about buying the Massdrop HifiMan XX headphones, but the look of that headband - shudder!!

But, the knob seems to have hit almost a primal nerve among some... but, hey, to each their own!!!

As to Z... I enjoyed watching him, even if only for entertainment, for a while, until I realized that the quality of his advice was sometimes spotty and certainly way too subjective, and his presentation style definitely targeted at people about 30 years younger than I am.

 

[danadam]

The problem with remote controls is that the buttons wear out!

It's called burn-in ;-)

 

[Addicted to music]

The mechanical feel of the volume knob doesn't have anything to do with the sound quality. The size of the pot or the volume knob have noting to do with sound quality either. Aesthetics also have no impact on the sound quality. Yet, these are the main points of critique of the HP-1 (including in this thread). Humans are not rational critters. That's one of the reasons I'm studying psychology.



Also, the argument that volume pots degrade sound quality doesn't hold water. As you can see from Amir's measurements, it's perfectly possible to get good performance even with a volume pot in the signal path.

Tom

Typical reply for everytime I post these comments. Take the cheap way out! Im Absolute convinced that electronic is the way to go. Didn’t you say you have been disappointed on a unit that had a scratchy pot... That should ring alarm bells.

 

[garbulky]

But it's a headphone amplifier. The user is only going to be 3 to 5 ft away from it and surely wouldn't need remote volume? Are people really that lazy?

I use my remote control on my Emotiva DC-1 DAC all the time. It is fed in to the basx a-100 which feeds my sennheiser HD600. People assume that headphone use is on a desktop computer but it can easily be used in a living room situation - like mine. For which a remote is a must as I'm reclining in my chair far away from the dac.
As for nice remote controls - it depends on what you mean by nice. With expensive remotes: one persons "nice" is another persons horribly clunky".
While compact plastic remotes is one persons "nice and minimilastic," and another person's "cheap toy."
For instance I love the Emotiva XDA-1 heavy remote controls

Emotiva XSP-1

Made out of aluminium. It's great! But if it falls on your foot - ouch! It also doubles as a home defense tool against a zombie horde.

 

[amirm]

Did you catch the review? Link maybe

Sure: https://www.neurochrome.com/tortuga-audio-ldr3/

It will make audiophiles that use them weep if they ever bothered to understand the measurements.

 

[Soniclife]

You bought Apple gear huh?

Slander, take that back .

There should probably be an updated Godwin's law for Apple, it never goes well.

 

[maverickronin]

Typical reply for everytime I post these comments. Take the cheap way out! Im Absolute convinced that electronic is the way to go. Didn’t you say you have been disappointed on a unit that had a scratchy pot... That should ring alarm bells.

There aren't any volume control chips up to the standards of the rest of the amp. @tomchr could either put his foot down like @March Audio and have no volume control at all or spend more than the cost of the rest of the amp on a relay/resistor ladder with a decent number of steps.

I'd prefer it had at least an RK27, but there's no other practical choice but to use a pot of some kind on the HP-1 with out reducing performance or doubling its cost.

 

[tomchr]

Typical reply for everytime I post these comments. Take the cheap way out! Im Absolute convinced that electronic is the way to go. Didn’t you say you have been disappointed on a unit that had a scratchy pot... That should ring alarm bells.

Of course I'm disappointed that one pot has failed. However, as I also pointed out, one pot out of many is still a low failure rate. That doesn't mean that all pots are bad or that good performance can only be had with an electronic volume control. I've had many pots that never developed scratchiness. And as you can tell from the measurements, the fact that I use a pot does not impair performance.
Any failed component will impair performance. I would also be disappointed if an encoder, micro controller, or volume control chip had failed.

Tom

 

[tomchr]

There aren't any volume control chips up to the standards of the rest of the amp.

Well. That's another thing.

@tomchr could either put his foot down like @March Audio and have no volume control at all or spend more than the cost of the rest of the amp on a relay/resistor ladder with a decent number of steps.

Another approach would be to have a digital-only headphone amp. Use the volume control in the DAC (maybe combined with an external relay-based attenuator).

Tom

 

[tomchr]

Tee-hee... Looks like the Massdrop THX 789 uses the Alps RK097 pot as well: https://www.audiosciencereview.com/...n-of-massdrop-thx-aaa-789-headphone-amp.5327/

Tom

 

[restorer-john]

Oh go on Tom, splash out and put an RK-501 in the thing, with a nice perspex window in the lid, lit by LEDs so the audiophiles can impress their mates.

https://au.mouser.com/ProductDetail/ALPS/RK50112A0004?qs=sGAEpiMZZMtC25l1F4XBUwTm7BmftDV%2buV4AjfPhqtM=

 

[solderdude]

The problem with remote controls is that the buttons wear out!

My experience with repairing remotes is that most of the damage to remotes is caused by fluids inside the remote (drinks spilled over it and sweat because people tend to hold them in their hands), batteries leaking and eating away contacts and the occasional chewing of dogs.
Also have seen a lot of printed markings disappear from the rubber buttons.
I don't like to have an array of remotes anyway.
I knew a customer that had a plank and taped all of his remotes on it.
Yes, there are programmable remotes but often don't have all the needed functions/buttons.
Yes, you can use the phone but found in a lot of cases the range falls a bit short.

I am old... give me a nice 'analog' volume control with a nice feel to it and some quality with respect to tracking and not developping scratchy sounds.
Not having any amounts of DC on it or currents entering the wiper helps a lot.
The RK097 is quite usable and small in size and price. Sure there are better pots around but also ones that are worse. RK097 is a nice affordable pot.

As with headphones. A headphone can be very good sounding but if it doesn't feel 'good' on the head people tend not to use it that much.
Audio is not just sound... it is also the eyes (looks) and 'feel'. Thinking only the electronics matter may be 'tech' thing only.

 

[JJB70]

As to Z... I enjoyed watching him, even if only for entertainment, for a while, until I realized that the quality of his advice was sometimes spotty and certainly way too subjective, and his presentation style definitely targeted at people about 30 years younger than I am.

I don't give that much credence to his opinions on sound quality, and some of his statements on technical aspects are decidedly shaky (he once gave a completely incorrect explanation of balanced connections). Yet for all that I just enjoy his videos, he strikes me as being a bit like Jeremy Clarkson, formerly of BBC Top Gear and now the amazon Grand Tour, in many ways an opinionated idiot and more an entertainer than reviewer yet in his own way he often comes out with some really rather well considered and insightful views and opinions (generally tangential to the subject of a review).

 

[andymok]

make your way to the professionals, send it to the studios.

Guys make their own cable anyways, may just as well build one for themselves.

an output selector, front panel on/off, option for rack mount kit would be nice though.

 

[Headphonaholic]

I don't give that much credence to his opinions on sound quality, and some of his statements on technical aspects are decidedly shaky (he once gave a completely incorrect explanation of balanced connections). Yet for all that I just enjoy his videos, he strikes me as being a bit like Jeremy Clarkson, formerly of BBC Top Gear and now the amazon Grand Tour, in many ways an opinionated idiot and more an entertainer than reviewer yet in his own way he often comes out with some really rather well considered and insightful views and opinions (generally tangential to the subject of a review).

I'm a fan of z because he is really passionate about what he does. I've watched his videos for a long time now and he's come a long way. He's also very entertaining and I think that is why many watch him. I watch his videos for his headphone and occasional speaker reviews. Amps and dacs I come here . My advice when you decide to follow a headphone reviewer is to find reviews of ones you own or have owned and see how much your thoughts line up with theirs.

 

[AndrewMason]

And here is the Massdrop THX 789 using the same input level but with 1/3 the power at 168 milliwatts (can't do 400 mwatts @ 300 ohm):

View attachment 17793

HI Amir. Thanks for doing the comparison.

It's possible your measurement of the 789 here might be on the verge of clipping, or something else in the setup is funny.

With my 789 at 2.0 V rms input, high gain, I get the attached plot. Pout is 148 mW. My 3rd harmonic is 7-8 dB lower.

Also please note the attached Zout vs freq for the 789 that differs dramatically from yours (< 0.1 Ohms @ 1 kHz vs 0.8 Ohms). I'd love to help you make an improved setup to measure this properly on all your amplifiers.

Thanks, Andrew