Tom Christiansen Audio HPA-10 Review (Headphone Amp)

[Cahudson42]

Colors? What next? 'Case CNC machined out of solid titanium billet'?

I'll take my PEQ..

 

[Doodski]

Colors? What next? 'Case CNC machined out of solid titanium billet'?

I'll take my PEQ..

I worked high end car audio for years. It was great. Heavy duty lil things with dials and knobs/mechanisms that go in and out and voila mobile electronics switches/controls, combO PCBs, SMDs and mechatronics. Adding a parametric circuit to one of the finished headphone amps is not that far fetched and is possible.

 

[gvl]

There is something irrational that makes me want to buy one over the obvious competitors.

 

[pma]

Excellent results, congratulations @tomchr

 

[Doodski]

I downloaded the pics of the HPA-10 and the HPA-1 and they are both the same resolution c/w proper file names too; I was surprised. The HPA-1 has a much better pic. It appears a proper circular polarizing filter and light hood was used to eliminate the hard edges of shadows and to cut through the glare. With this kinda eye candy it all helps.

 

[pma]

Thanks for the hint, @Doodski , I will check the DC/DC converter that we can see in the photo

 

[tomchr]

There is something irrational that makes me want to buy one over the obvious competitors.

Humans are not rational critters. You should definitely buy one. Not that I'm biased or anything...

Tom

 

[tomchr]

The HPA-1 has a much better pic. It appears a proper circular polarizing filter and light hood was used to eliminate the hard edges of shadows and to cut through the glare.

No, actually. It's just the angle of the light. I always use a lens hood. There's no reason not to. I'll see if I can take a better picture of the HPA-10.

I don't think I even have a polarizing filter anymore. I used them quite a bit when I was doing landscape photography.

Tom

 

[escalibur]

Great performance as expected. Great work @tomchr

 

[Objectivist01]

Now I appreciate topping even more for making l30 at that price.

 

[Nango]

Now I appreciate topping even more for making l30 at that price.

This is not the right place for doing this, here is about TCA HPA-10, it's not fair. Not to mention you can't compare mass production with Tom's work.

 

[Tatteredmidnight]

@tomchr not sure what your manufacturing process is like, but if you are building these in house, offering some modifications on a build to order basis (with the appropriate lead out time) could give you some room to differentiate. Things like different gain levels or colors could be done this way, but if you are having these assembled in batches for you, this obviously might not be practical. I know JDS Labs will do some customization on request like engraving or adding weights to the base of the Atom.

 

[sq225917]

Have you thought of doing a collaboration with Massdrop Tom? As well as shifting units it could bring a lot of people to your other lines.

 

[digititus]

If you can make the volume pot go to 11, I'd consider buying it . Nice product. Well done.

 

[groovybassist]

There is something irrational that makes me want to buy one over the obvious competitors.

Just do it! I have Tom's HPA-1 and it's a terrific headphone amp. Tom manages to marry objective performance and subjective sound quality in a way that I've found is a rare commodity these days.

 

[groovybassist]

Great job @tomchr !

 

[DuxServit]

I downloaded the pics of the HPA-10 and the HPA-1 and they are both the same resolution c/w proper file names too; I was surprised. The HPA-1 has a much better pic. It appears a proper circular polarizing filter and light hood was used to eliminate the hard edges of shadows and to cut through the glare. With this kinda eye candy it all helps.
View attachment 102602
View attachment 102603

Just love that maple leaf logo at north part of the board
Congrats @tomchr

 

[Atanasi]

Even from the big asian guns, yep they offer more value, if we don't need anything else, I don't think I've seen something offer more power on a straight unbalanced TRS, easily portable, for this price. The compact package is key, good job.

As for portability, 5 V DC is the best, as any power bank can give it. Competitors usually need mains power.

 

[AndrewDavis]

It’s easy to like anything that Tom produces.

 

[tomchr]

Just do it! I have Tom's HPA-1 and it's a terrific headphone amp. Tom manages to marry objective performance and subjective sound quality in a way that I've found is a rare commodity these days.

Thank you. That's precisely what I aim for, actually.

@tomchr not sure what your manufacturing process is like

That's one way I differentiate, actually. I need to let people know that... A quality circuit and PCB layout is just the beginning. My raw circuit boards are made in Canada – just outside Toronto, actually. I then order the parts from Mouser, Digikey, and other authorized distributors in Canada and the US. Some parts I order directly from the manufacturer. This ensures that I get genuine parts. I then hand-carry the parts and boards to my assembly house in Calgary.
The assembly process is quite elaborate and involves automated optical inspection at many points in the process. The facility I use is set up for IPC-A-610 Class 3 production, which is the quality level used for mission critical electronics that cannot be allowed to fail. Think aerospace, military, life-supporting medical equipment, etc. The assembly house only offers one workflow, but differentiates on the final inspection. My boards are assembled to IPC-A-610 Class 3 and inspected to Class 2 at the end. They charge quite a bit more for the Class 3 inspection. That said, over the summer we ran an experiment on some boards I was having built then. They inspected 2000 solder joints across 10 boards and found two (2) that 'only' met IPC-A-610 Class 2. The rest met IPC-A-610 Class 3. Class 3 requires the solder fillet to cover more than 50 % of the pin height on an LLP/QFN package, the two Class 2 solder joints reached 50 % vertical coverage, but did not exceed 50 % coverage, and were therefore Class 2.
IPC-A-610 Class 2 manufacturing is used for equipment intended for a long service life with minimal service disruption. Think computer servers in data centres, high-end laptops, etc. Most consumer goods are manufactured to IPC-A-610 Class 1, which is used for cost-optimized goods with a short service life, where a service disruption is acceptable. All that is required for Class 1 solder joints is that there is a connection; not that the connection is good.
Anyway. Long story. I write about it in greater detail on my Neurochrome page and need to create a similar page for TCA. You can find my write-up here: https://neurochrome.com/pages/the-north-american-advantage

I complete the rest of the assembly process, i.e. the process of putting the PCBs into the chassis and testing the amp. All amps have been through a full test suite, which includes THD+N sweeps with 300, 32, and 20 Ω loads, noise measurement, multi-tone IMD, etc. I want them to work well once they're in your hands.

This process means that offering custom circuit boards is out. But if I find a good engraving place, I could entertain offering a custom engraving job. I think I would rather leave the customization options for future, more expensive products and have the options be something that make a difference, either in the performance of the amp or in functionality.

As for portability, 5 V DC is the best, as any power bank can give it. Competitors usually need mains power.

That's exactly why I went with 5 V for the HPA-10. Want portability? Bring a power brick! I'm also curious how it would perform on something like a cellphone charger. The charger for my iPhone is about the size of a regular NEMA-15 plug.

I went through quite a bit of trouble finding a power supply that would work well for audio. Many switching supplies allow the mains frequency to seep through to the output, which results in mains-related spurs on the output - even after going through two isolated switching converters! The XP Power supply I ended up using with the HPA-10 was about twice the cost of the lowest cost contender, but the XP Power provided much better performance, so I bit the bullet and went with the more expensive supply.

Just love that maple leaf logo at north part of the board

Yeah. Drawing those was definitely a proud Canadian moment.

Tom