Matrix HPA-2C Classic dekstop headphone amplfier, DAC and pre-amplifier

Hello everyone. First off I must thank Eminem, (no, not that one) from Matrix Audio for allowing me the opportunity to review or should I say tinker with this product. Home page of the Classic.

(Rather than do an actual review of this amp I’ve linked here Matrix HPA 2 Classic to what I think is a very good and capable review of this product)

My article deals more with its versatility and use with various dac/daps and cables to show you how and what you need to connect them to the HPA-2 Classic.

The Classic was used with the following products: Music Bee with WASAPI active on a Windows 10 PC, iPad 10.5, Pioneer XDP-300R, Cayin i5, and the Astell & Kern Jr (AKA the Stepchild).

The following cables were used:

USB Type A to B

USB Type B to C

USB Type A (female) to Micro B

RCA stereo audio cables to 3.5 stereo plug

Apple Lighting USB camera adaptor

Special guest iFi Gemini 3.0 USB iFi ‘FINAL’ USB Type A to B


Music Bee link was used as my MP3/Flac player, as you can see it allows you to directly hook up via WASAPI link via USB Type A to B iFi Mercury 3.0 so the Classic signal flows through nice and cleanly!


Figure 1 Music Bee audio player preferences

I used the included USB Type A to B and then ditched them like day old sushi for the absolutely sexy and stunning iFi Gemini 3.0 cable (that gets its own review because this cable made this amp and everything else kick it up several notches!) The last cables you'll ever need!

Figure 2 & 3 iFi Mercury 3.0 iFi “Final” USB-A to B from PC to the Classic




In terms of versatility, the 300R is easily one of the most connection friendly DAPs there is. There is nothing it has not worked with that I have thrown at it. Here it is with the Classic hooked up with a USB Micro B to USB Type A (female) to USB Type A to B. No fuss, recognizes it and you’re ready to rock!






Figure 4, 5, & 6 Pioneer XDP-300R to Classic via USB micro B to USB Type A (female) to USB Type A to B


Talk about a mighty midget! This little thing is my grab and go DAP! It even acts like a DAC! Anyway, As you can see, I am using USB Type B to C cable. As with the 300R, no fuss! Read the Classic right away and was ready to go!



Figure 7 & 8 Shanling M1 to Classic via a USB-B to C cable.



Grrrrrrrrrr! I have a love/hate relationship with this thing. Astell & Kern released this product, issued one update, they blew it off completely. Normally not a problem, but with piss poor Bluetooth, a flawed IU, and various other issues that are conveniently ignored, on the FAQ concerning this product, you can see why I have called it The Stepchild. May you rot in hell Astell & Kern!

Sorry, went off on a rant there. So why do I still keep this discarded and flawed DAP? The damn analog sound! Whatever other problems this thing has, the Wolfson WM8740 DAC chip rocks and almost makes you forget all the other flaws with this product. Almost.

As you can see, you can use a 3.5 analog stereo plug to stereo RCA plugs when hooking it up to the Classic. No, don’t bother asking about using the USB Micro connection on the Stepchild, there’s no digital output from the USB micro connection. I told you, this thing can disappoint like a slutty girlfriend. The aforementioned Wolfson chip makes up for this, though. With the HPA-2 Classic, the music comes out very nice.






Figure 9, 10, & 11 Astell & Kern Stepchild to Classic via 3.5 stereo line out to stereo RCA cables.


While the i5 has digital output, the Classic doesn't have a SPDIF input, so I tried using USB Type B to C but the i5 is very inconsistent being used in this way. Too sensitive and drops the connection too often. So lacking the SPDIF, I went with the line out on the i5. Worked like a champ!






Figure 12, 13, & 14 Cayin i5 to Classic via 3.5 stereo line out to stereo RCA cable.




Apple, being Apple, makes it necessary to get the proprietary Apple Lighting USB camera adaptor to get it to work with DACs. So here it is working with the Classic in conjunction with the USB Type A to B cable. And work it did.






Figure 15, 16, & 17 iPad 10.5 to Classic via the Apple Camera Adapter to USB Type A to B.


There you have it, this puppy can be used with many different items and all you need are cables!




Thank you for reading, take care!




PS

Thank you Pat, Karina, and Vince from iFi for letting me use these Mercury cables and the other items from your company! Good luck getting these cables back! ;-p

"Freedom of expression is the matrix, the indispensable condition, of nearly every other form of freedom." Benjamin Cardozo



Introduction

Based in the Xi'an Economic and Technological Development Zone, Matrix digital is a brand that has gained significant global coverage in the digital audio sector. Utilizing advanced research facilities and professional audio testing equipment they aim to pursue optimal product quality with excellent service and reasonable prices.

Today I'll be taking a look at the HPA-2 Classic headphone amplifier, which according to Matrix's website

"is the improved model of HPA-2, the optimized circuit design, new style appearance, exquisite processing technology and excellent performance to make it better."

Disclaimer

This sample was loaned to me for the purpose of an honest review. All opinions and observations here are my own based on my experience with the product. I have no affiliation with the company and do not benefit financially from this review. More of my reviews can be seen from the link in my Head-Fi profile or on my blog.

The HPA-2 Classic has a MSRP of $289 and is available for purchase from popular audio sellers and of course Matrix's own online store. I'd like to thank BKK Audio for the loan unit.

Official Matrix website: http://matrix-digi.com/en/index.html

The full list of specifications can be found on the official website: http://matrix-digi.com/en/specifications/102/index.html



Packaging and accessories

The HPA-2C comes in a fairly plain white box with nothing but "Matrix Audio" and a QR code printed on the front. On the inside we find the unit wrapped in some protective material and held securely in a white foam inlay. Apart from the DAC/Amp there's also a user manual, power cable and USB cable. Not a lot there but it's all you need to get things going out of the box and helps to keep prices more reasonable for the consumer.



Build and usage

The first thing you'll notice about the HPA-2C is it's BIG. It was like pulling an engine block out of the box. It's pretty hefty too, weighing in at a solid 1.22kg. You'll want to have a decent amount of desk or table space available for this. Once you get over the shock caused by the size, the next thing to note is that this is a very nicely machined chassis. There's a single Matrix audio branding logo on the top leaving the rest of the surface clear. The sides of the chassis are slightly concave and lined with two rows of ventilation slots running from front to back and it's a good thing too because this baby gets very warm when in use.

The front panel is a lovely, thick and sturdy slab of aluminium, again nicely crafted with all smooth edges and polished to a sheen finish. On the panel (from left to right) are the 6.35 mm headphone jack, a blue power LED, an input select switch. These are all in a nice little recessed section that separates the section and makes the panel a bit more interesting to look at. Finally there is the volume knob. The headphone jack is nice and tight and feels very secure when plugging headphones into it. Fortunately the LED is very small and not too bright so most of the time it goes unnoticed unless you're looking directly at the front panel. The select switch also feels of a high quality and is used to choose between USB and Analog signal inputs. There is a small U and A next to the corresponding switch position but the text is very small and difficult to see unless you're in a really well lit area but it's unlikely to cause anyone grief. The volume knob is textured and nicely weighted giving you firm control and precise adjustment.

Populating the back panel (from left to right) are a USB input, High / Low gain switch, analog RCA input, analog RCA output, power switch and 3 pin power socket.

Getting things going is a simple matter. Plug in the power and USB or analog source, stick in some headphones and you're good to go. Just make sure the input select switch is in the right position first. For Windows users you'll need to install the Matrix driver to get it working with your PC (supposedly this won't be necessary much longer as Windows is soon adding native support for USB DACs).



Sound

With an output impedance of 10 ohms these aren't really geared towards driving sensitive IEMs and it shows with a noticeable buzz/hum. With higher impedance headphones the buzz disappears but it was still present on sensitive full-sized cans.

The CIRRUS LOGIC CS4398 DAC has a great sound that is transparent and lively, delivering music in an energetic and engaging fashion. I had good results using the built-in headphone amplifier and also when using the line out to my FX Audio 1002A amplifier and speakers. Instrument separations is fantastic as is soundstage. There might be the slightest bit of smoothing in the DAC's output. The CS4398 has selectable fast and slow roll off digital interpolation filters and in my opinion Matrix has made good implementation of its capabilities.

For the amp stage, well I briefly touched upon it above but basically you don't want to be using it with anything overly sensitive. Extension of highs and lows is on point and with some good headphones delivers a truly enjoyable experience. With the Beyerdynamic DT990 Pro (250 ohms) there's no evident background noise and I found anywhere between 40%-60% volume on Low gain was plenty enough power to drive these. Low gain output = +6dB and High=+15dB (160mW at 600ohms) so on paper the HPA-2C should be able to power just about anything you throw at it.

With the Ultrasone Performance 860 (32 ohms, SPL: 94 dB) I didn't detect any buzz while on the MSUR N650 (32 ohms, SPL: 105dB) it's immediately noticeable so as long as you're using something that isn't too efficient you should be okay but take that with a grain of salt. Speaking of the Ultrasone, they sound nice paired with the Matrix with good soundstage and load of details but seems a little "on edge" for lack of a better term. The pairing of the DT990 worked better overall for me, sounding effortlessly smooth yet full-bodied and energetic at the same time.

Comparison

Audinst HUD-MX2 ($200 USD)

The HPA-2C has a more energetic and airier sound while the HUD-MX2 has a smoother, more laid back presentation. Both have good power output but the Matrix pulls out ahead with some impressive specs. Besides, to utilize High gain on the Audinst you need to actually open up the chassis to make the change. The Audinst fares better with sensitive IEMs which aren't really viable with the Matrix due to the constant buzzing. Both units get pretty hot when in use. The Audinst has a much smaller footprint so occupies a lot less desk space. So easy recommendation would be: for use with IEMs it's Audinst all the way and similarly for full sized headphones the Matrix is the way to go. If you want to use IEMs and headphones the Audinst should do the trick unless you have some seriously hard to drive or inefficient headphones.

Conclusion

The HPA-2C is a beautifully crafted beast of a DAC/headphone amplfier. For those wanting something to hook up to a computer for full sized headphones at a reasonable price this would be a great choice. It is a fine sounding amp and not too hard on the eyes either. It would be nice to have an additional 3.5 mm headphone jack added to the front panel - there's certainly enough room for one. At $289 I think it does really well and where sound quality is concerned I personally prefer the Matrix to the HUD-MX2 and possibly the more expensive JDS Labs The Element. If you're looking and this is within your price range it's definitely worth considering.

 I orginally purchased this amp on May and held off my review until August.
 
Headgear used: Q701, er4pt
 
i Prologue
ii The search
iii Purchasing
iv Arrival
v Initial impressions
vi Usage over the months
vii Final verdict
 
Prologue:
I previously owned the micca origen amp/dac unit that I purchased for $100. The amp was powerful enough to drive my Q701s on high gain past 12 o'clock, so it was good enough for my needs, but the DAC ultimately left a bit to be desired as the background still had some noticeable hiss. The build quality was seemingly great and the volume knob was simply perfect. The only real issue was the micro usb input in the back which was fragile and got loose over time, when everything appeared to be working great, the tiny amp fell off my desk as I was turning and the micro usb port snapped right off the pcb.
 
The search:
I had previously planned to upgrade to the schiit bifrost and lyr 2 as my end game amp/dac set up sometime in the future, but because of this unexpected occurence I had to search for a replacement as soon as possible, but I didn't want to purchase the same amp again as this was an opportunity to upgrade. I knew the o2/odac combo was a solid option but based on countless reviews, they apparently did not pair very well with many TOTL headphones such as the hd800 and k812 which I might as well upgrade to sometime down the road. Several headfi threads later, alas I stumbled across the matrix mstage which has high praise in both performance and value yet seemingly pairs greatly with most TOTL headphones. I headed onto matrix's website to see if they had any new models that fixed the mediocre design and subpar DAC that had me in turmoil on whether or not to purchase it. Well what do you know, they had just recently launched the new mstage hpa2 classic with a completely redefined design, slightly improved amp, and completely new cirrus logic flagship DAC. They also had a technically superior hpa3 model, but there was no competition when comparing it to the beauty of the hpa2 classic. Normally I am not drawn into amps with exotic designs, but this amp was in a whole new league that set itself completely apart from any previously existing amps that I knew I had to buy it, even if it meant taking the risk of buying a new product without any reviews.
 
Purchasing:
After adding the mstage hpa2 classic to my cart and proceeding to check out, I noticed there was no USA option, it turns out matrix has a separate website for their USA customers. After figuring this out and visiting the american version of the site, I noticed the amp was priced at $389 rather than the MSRP of $289. After contacting the given email, shortly after I was given a response stating that it was merely an honest mistake and the price was set back to the MSRP $289 price. Relieved to find this out, I immediately purchased and waited anxiously for it to arrive from china.
 
Arrival:
About a week later, the package arrived and after ripping through the package I quickly plugged in the power and the USB and turned it on. No sound. Okay maybe I just need to install the drivers. 5 driver installs later from various sources, it was getting to me that it wasn't an issue with drivers and rather my unit was defective. After contacting matrix audio, I received a quick reply stating there is a small red voltage switch on the side that changes between USA and EU voltage. Turns out I was trying to use my amp under the EU voltage switch. 
 
Initial impressions:
So with the US voltage switch finally turned on, I played some music with my Q701s. My ears exploded with how awfully loud it was. I immediately switched it into low gain; much better. Despite what the raw specs sheet states, this amp is extremely powerful and I have to dial it down to 9 o'clock on low gain to get my power hungry Q701s on my prefered listening level. I tested an instrumental track that I know produces a lot of hiss with my previous amp. Gone. The hiss is absolutely non existent, even when pairing it with my sensitive etymotic er4pt iems, there is very little sign of hiss. The unit gets warm after prolonged usage, but never hot enough to get uncomfortable to touch, unless the room temperature is already very high.
 
Usage over the months:
I held off my review for many months to see how the amp held over time. I knew I had read complaints on the previous mstage models having issues with the cheap volume knob, I had assumed matrix would have solved this by their 3rd revision; I was wrong. The volume knob rattled and as much as I tried to ignore it, it got worse over time. Eventually it got very loose so I gave it a tug and it just came right off like a cheap plastic cap. Incredibly disappointed in the build quality of the volume knob. A little bit of super glue fixed the problem, but it doesn't dial as smoothly as before. Some words of advice to matrix if it isn't clear enough already: fix the volume knob!
 
Final verdict:
So how do they sound? This amp won't make your headphones into bass monsters. The midrange won't pop in your face. The highs won't be amplified to uncomfortable levels nor will they be drowned out. Despite what many reviewers state out amps to try to sell you into buying exotic gear, there is very little variance, sound wise among different solid state amps. They reproduce the source faithfully as they should, and as a result they sound great. I'd like to call out many so called audiophiles that treat tube amps as a prerequisite for decent volume with good headphones when solid state has proven with time and time again to have superior fidelity while driving even the most demanding headphones, I wouldn't be surprised if the hpa2 classic could manage to drive an he-6. Despite what reviewers stated about the mstage blossoming the soundstage, I heard essentially no increase in soundstage. My etymotics sounded slightly more defined and precise, but the change isn't outright noticeable. If you buy an amp expecting a radical change in your sound, expect to be disappointed, upgrading headphones are better suited towards that. I've completely abandoned my plans on upgrading to the bifrost/lyr setup and I find myself perfectly content with the mstage hpa2 classic as an end game setup for years to come, if the volume knob holds up for that many years that is.... Ironically, my unfortunate amp breakage has lead me to find my end game setup prematurely and save me hundreds in the long run.
I wrote this review as I feel this amp is serverely underrated and deserves more attention as it has many strengths with little flaws. If matrix can fix the volume knob, this amp would be the absolute go to amp/dac combo for under $300
 
Edit: It turns out there is a hole where a screw used to be, and I've been told it would only take a screwdriver to fix the loose volume knob. So basically this amp has all the bells and whistles I wanted without any drawbacks as this was a mistake on my part 
 
Edit 2: I have used my new w5000 headphones with this unit and it had a buzzing noise when no music was playing, it was not like my previous amp which had a hissing noise coming from the DAC, the noise coming from this headphone sounds like a static buzzing noise. To test this, I took off the high impedance adapter from my er4pt and it exhibits the same noise too. Will be knocking a star off.

Firstly I would like to thank Matrix Audio for sending me this sample to review, in exchange for my honest opinion. I always try to write honest reviews, this unit received over 50hrs of burn-in before reviewing, no differences were noted.
 
Gear Used:
Dell XPS 15 / Audio Opus #1 > Matrix Quattro II DAC > Matrix HPA-2C
Dell XPS 15 > Matrix HPA-2C
Headphones: Fischer Audio FA-003ti W / Fostex T50rp Mk3 / Fostex TH-500rp (IEM’s more on that later)
 

 
Tech Specs:
A comprehensive list can be found on the Matrix Website: http://www.matrix-digi.com/en/specifications/102/index.html
MSRP: $289
 

Packaging, Build Quality and Accessories:
The HPA-2C comes in the standard White Matrix Audio box, it is made of quality cardboard and has a good finish, albeit plain. This is a device you will have read about or seen rather than needing the packaging to sell it, because of this no specs or images are needed on the box. Inside the box you get the HPA-2C very well padded in a foam insert, along with the accessories and instructions. The device is well packaged being held with foam, and also the device has a thin protective pouch over it. Overall the packaging is plain, but very well made and serves it purpose of getting the product to you undamaged, even when handled by the worst of couriers.
 

 
The build quality is superb, I didn’t find any blemishes on my unit, the finish is a neat matte black and everything fits together very nicely. All the inputs and outputs are gold plated and of excellent quality, the headphone socket is tight, the volume knob rotates every so smoothly. It all feels very sleek, smooth and solid. The full metal design with small opening on the sides also help keep the unit cool, and it only gets a little warm when being used, considering it is a class A amplifier.
 
Accessories included are the power cable, which is a standard 3 pin kettle lead, a USB cable, manual and CD which includes the driver. All in all you get everything you need to get it up and running.
 

 
Functionality and Setup:
The main improvement Matrix have done is add a high quality DAC to the HPA-2 amp as standard, not longer having it as an optional extra. The HPA-2C can be used as a pre-amp for a stereo setup, as a headphone amp only and as a DAC/Amp combo, you can also use it as just a DAC but the volume control controls the RCA output level, so as a DAC it doesn’t have a fixed line level out.
This amp has 2 gain settings, however I have never needed high gain, it is only really needed for very hard to drive headphones.
 
Setup was nice and easy, I am using windows 10 and just installed the driver and it was simple to setup and use.
 

 
Sound:
Well what can I say, this is a powerful desktop amp that has a great built in DAC for a neat all in one solution. It is suitable for full size headphones, and inefficient IEM’s only, with most IEM’s there is a constant audible hum unfortunately, which is never audible with full size headphones, no matter how efficient they are, a little odd. I should add that the output impedance is 10 Ohms so it is best suited to headphones 80 Ohms and over really.
 
This as an amp on its own tries not to add too much flavour, it is powerful and balanced, well refined and ever so slightly smooth. It takes the slightly sharp edge off the sound which makes it an enjoyable listen. It may not be the flattest in terms of overall sound, but it is also not as smooth as a valve amp at the same price. It works wonders with Beyerdynamic T1 1^st Generation as it takes the edge off the slight sharpness in the treble without taking away the detailed nature of the headphones. The sound is articulate and extended on both ends, with the FA-003ti you get the great separation and soundstage, along with the very tight and detailed sound, but the amp adds a little warmth and adds a little something that makes them sound tonally correct.
 
Using it as a DAC/Amp also works very well, I cannot hear a huge difference between the Quattro II and the internal DAC, the Quattro II definitely has the upper hand in detail retrieval and also refinement where you can nitpick things a little easier, and the Quattro II is fantastic in its own right, but if you only need a USB input I cannot see anyone going wrong with just using the internal DAC and this as a standalone device.
 

 
Using the Fostex TH-500rp I still find myself going to my Feliks Audio Espressivo Valve amp, as it sound smoother and overall compliments the TH-500rp better than the HPA-2C, the HPA-2C does make them sound a little more open and also extension up top is better, but with the Espressivo they sound buttery smooth. This is not a fault of the HPA-2C, just personal preference.
 
Comparing it to the JDS Labs Element, the HPA-2C has a touch more authority and body, the Element sounds a little cold in comparison, even though it is an exceedingly good product. I feel the HPA-2C adds some realism to the sound. Both very good products, and the Element works better with IEM’s but the HPA-2C works better with hard to drive headphones.
 
Conclusion:
This is a great looking, well built amp/DAC combo that would stand proud as an all in one desktop solution, or as a lone headphone amp fed by another source. It is perfect for driving hard to drive full size headphones effortlessly with control, body and refinement. It may not be the most versatile amp out there, nor is it the flattest sounding amp, but is does offer a slightly full sound which I find works very well with the Beyerdynamic T1, Fischer Audio FA-003ti and others. Overall a great device, with an MSRP of $289 I can highly recommend it.
And if you are adventurous the op-amp is interchangeable too, so it opens up the possibility to roll others.
 
 
Sound Perfection Rating: 8.5/10 (the hum makes it not suitable for IEM’s, but if you use it for what it’s made for, it is fantastic for the price)