Lauri Cular gets his magic towel and liniment ready for The Big Rig Showdown – which is the true mobile music master? The Cypher Labs Theorem 720 vs The Cypher Labs Solo -R / Just Audio AHA-120.
For many a year, we’ve had great fun at the expense of the music fan on the move; what about those roller skaters with half a coconut over each ear? Then of course there’s the Atlas figure with a ghetto blaster and curvature of the spine, and who can forget that legion of listeners with those white buds of mediocrity?
“Darn these Confederate batteries!”
For some however, no compromise is acceptable; great sound quality just has to be paramount. A lump in the trousers causes no embarrassment in such cases. So who exactly is trying to get these big things in our pants?
There’s a wide selection of portable bits and bobs as we all know; with the more static listener, there’s known to be an entry or ‘low’ end of the market and a high end. Portable devices, by the nature of who they’re generally aimed at, are mostly built around price and convenience; some of them only accepting MP3s or similarly lossy file formats.
Apple’s recent impact on the portable audio market is well known, and although their products have a fair reputation for out-of-the-box audio quality, it’s very difficult to satisfy all scrumpers. Due to the success of Apple’s fruits, other manufacturers deem it worthwhile designing ways to improve the sound quality of these devices.
It’s well known that a low-cost cable can be attached to a 30-pin connection which provides a line-out signal; a signal which bypasses the internal amp of the iDevice, to be fed into an external amplifier. This can give sound quality a boost, certainly where less sensitive headphones are involved. Line-out lightning connectors for newer devices are available via Apple, but they ain’t giving them away.
However, this cuts little ice with those who strive for their jive – Apple’s DAC is still doing the conversion to analogue. Perhaps understandably, Apple would not have such a marketable product if all components were as high-spec as possible, and the DAC is no exception. It’s to get the job done adequately.
Apple has been protective in the past when aftermarket manufacturers wanted to get in between their rind and pips; indeed a hefty royalty has been required should anyone want their product to truly interface with the iDevice’s software. This has affected the price of available gadgets greatly; hopefully this is changing.
Fostex’s HPP1 is one example of a DAC which will decode music on an iDevice, but here we will compare two high-end arrangements provided by Cypher Labs and Just Audio.
..The Theorem 720 with iPod Touch
On one side we have the new Theorem 720 from Cypher Labs; an all-in one solution providing both digital-to-analogue conversion and amplification. On the other, we have the Cypher Labs Solo -R, with separate amplification provided by Just Audio’s A-Class AHA-120. How do these compare, and is the extra bulk of a separate amp (and extra connections) worth it?
The headphones I used for this are at a similar level – the effortless Beyerdynamic T1. Being a semi-open headphone, these are not the first choice for portable use but are excellent for judging the subtle differences in sound quality between high-end rigs, and for illustrating how powerful the amps are.
The Theorem 720 blew me away with its accuracy and power, but the latter depends on the mastering of the recording. For instance Aha’s ‘Take On Me’ (what better to test this against the AHA-120?) was blisteringly loud, but Queen’s ‘Another One Busts the Dust’ needed more headroom. Of course, the T1 headphones are rated at 600 Ohms with 102 dB sensitivity, so the bar’s unrealistically high for portable power requirements. It gives a good comparative impression though.
Bass was present and under good control. The mids had great detail and strength, and the highs were crisp and clean. Soundstage and separation were very immersive, and I was very impressed with what I heard. However, specialist interconnects such as those supplied by ALO Audio were not used, just the standard 30-pin to Micro-B USB connection provided with the Cypher Labs unit.
It’s not hard to imagine that a plethora of high quality interconnects will be available soon for the Theorem.
..Just Audio AHA-120 with the Solo –R and iPod Touch
So then I popped on the T1s with the same 30-pin iPod – now with a Cypherlabs Solo -R, and the Just Audio AHA-120 headphone amp. There was an ALO Audio interconnect between the iPod and Solo -R, and an iBasso 3.5mm to 3.5mm between
the Solo -R and AHA-120. This rig has a slight advantage here.
The bass was a little more present, but by no means excessive. Mids were more recessed than with the Theorem, and high frequencies not so clinically accurate. The soundstage was a little narrower too.
But for all that, I far prefer the Solo -R/AHA-120 combo as it sounds so effortless and natural. The difference is like that of spandex and silk. Spandex is functional, comfortable and easily cared for. Silk on the other hand reqiuires a little more TLC and is expensive. But all that trouble seems unimportant when hitting the town with my silk shirt on – the pleasure of wearing ultra-stylish, comfortable and cool fabrics makes all that seem unimportant.
And so it is with the Solo -R/AHA-120. Even the sound of fingernails scraping the surface of a blackboard would create a large smile across my face when heard through this rig.
Just Audio‘s range of headphone amps make a nice change from the sleek appearances of similar offerings from larger competitors. This may sound like a backhanded dig at the styling of this range, but not at all. On the contrary, it gives the units a bespoke appearance; one that promises to reform the sound in a no-nonsense, pragmatic way.
The new uHA-120DS also operates as a fantastic DAC and the improvement over my little Behringer UCA202 USB soundcard was plain, even when using passive loudspeakers.
There is the option to switch between battery power and USB power if used as a DAC, and between ‘Normal’ and ‘Fast’ charging depending on which USB standard is possible with your set up. Installation is easy, I tried the 120DS with Windows 7 and good old XP and both were fine; the PC recognised the unit and had it working with no extra work necessary, only to chage the settings to make the unit the PC’s default audio output. I’m told that there is a similarly smooth experience waiting for mac users too.
I tested the unit against a FiiO E07K to see how the audio from these two amps/DACs compared. For this cross examination I used the excellent Phonak Audeo PFE 232 earphones; to let no nuance escape the jury’s attention. The FiiO sounded a little brighter on first impressions, but on closer inspection there appeared to be either a small boost to higher frequencies with the Fiio, or a smoother presentation with the uHA120DS.
The Just Audio unit came across as being more relaxed; it didn’t break a sweat under the pressure and gave some very convincing testimony. Perhaps given that the uHA120DS is 4 times the cost of the FiiO, there’s no surprise here. You always get what you pay for when it comes to witnesses.
An absolute discharge is called for in this case, which is a relatively rare event. The battery can last anywhere up to 40 hours, depending on which headphones are used with the device and the amplification used, etc.
Before you ask, there is no ‘dock’ for an iPod however. Take him down!
Just Audio specialise in creating smaller scale audio products that enable an uncoloured, natural and precise listening experience. Their initial product offerings consist of a compact battery powered class A headphone amplifier and a smaller pocket sized class AB headphone amplifier. There is also a range of Studio quality interconnects to suit different configurations.
Who are Just Audio?
Just Audio is the brain child of Justin Harris, an experienced electronics/embedded software engineer with a love of Music and Hi Fi, whom previously has worked professionally in the mobile/wireless devices product creation domain. His passion is infectious, he obviously relishes the chance to talk about his ideas, electronics in general and getting the very best out of Hi Fi gear. Justin has worked for some of the mobile phone manufacturing giants, you may even have some kit he was involved in already.
“This all started with designing some functionality to incorporate into my modified Quad 405 power amplifiers, to enable standby and best in class audio detection and wake-up functionality, with the intention to make this in such a way that it could be retro-fitted without making a mess of the existing internals. ”
It was a desire to get the very best of his own Hi Fi kit which lead to the ground up designs for the uHA-120 and now it’s Class A big brother the AHA-120.
In 2009 he decided to start his own company. “The main theme originally was modularity and utilisation of surface mount technology to enable making the modules small enough to fit in tight spaces. I wanted to make operation seem natural and intuitive to the end-user and perform better than other implementations that I’d experienced myself.”
Having such a strong engineering background seems to have provided Justin with an understanding that individuality, through modularity and customisation, will develop products with the end user always in mind. It can take a long time to find the bit of kit which has all the required abilities and compliments existing headphones or source. By understanding the wants and needs of the enthusiast he hopes to be able to bridge these difficult gaps for customers whilst keeping an eye on the shifting sands of the audiophile landscape.
“By early 2010 We had started to think along the lines of making a complete product that could be tested to the relevant standards. We had already built up a library of components and a capability to produce electronics modules. I’d been studying on various audio amplifier topologies and experimenting with my own Hi-Fi system at home, attaining both measurable and perceivable improvements. I’d also been looking at headphone amplification projects and products out of passing interest for some time and had already built my own headphone amp for use when I was working at the office. The idea occurred too me, why not use the technological advances to make a pocket sized headphone amplifier more akin to the standard one would expect from a respectable desktop amplifier. Of course, the idea of creating a pocket sized amp isn’t new, but we noticed that everyone in this market seemed to be just using an operational amplifier or some form of dedicated amplifier IC combination. Coming more from a Hi-Fi power amplifier interest area, we felt that using a commercial IC would never provide the same level of audio quality as a carefully crafted discrete circuit, so I set about building some prototypes of more discrete topologies usually found in larger power amplifiers. A few months later we had determined most of the system level components (battery, charging, connectors, volume control pot), along with a hybrid class AB topology that we had built in enough flexibility to fine tune and provide what I felt is a more High Fidelity sound, yet able to operate from a low voltage power source.”
With a direction that many enthusiasts will recognise Justin is still committed to customisation and the minor adjustments that provide the best possible performance. So far he has carried out many mods working closely with customers requirements. Several such projects have seen him build a range of Studio quality cabling and adding mods to hardware which have helped him shape the future direction of the Just Audio range and additional services. More about Justin’s big plans for the future of Just Audio and functionality upgrades (which will be available for existing Just Audio amp owners too) later on.
AHA-120 Put To The Test
Having a Pair of the truly excellent Beyerdynamic 600ohm Tesla T1 Headphones at my disposal, Justin suggested he send me the Just Audio Class A AHA-120 to test. Quite a few manufacturers have products in this small niche market, some fail to deliver improved sound quality or improved player usability with hard to power headphones, Justin expects the AHA-120 will be a great match to the T1’s. I have been using the excellent iBasso D10 with headphones regularly and also other acclaimed portable amps for some time now, this will be the first proper portable test with the Beyer T1’s.
Many audiophiles believe that class A gives the best sound quality with its absence of crossover distortion and reduced harmonic distortion. Class A amplifiers are typically more linear and less complex than other types, but they are very inefficient. This type of amplifier is perfect though for driving sensitive low distortion headphones where the listener wants the very best audio quality, without the massive electricity bill potential of a full sized class A HiFi system at home! Operating in class A means that the amplifier is always passing current through upper and lower sections of the electronics even when there is no signal, negating any artifacts as a result of the transistors turning off and back on again during the amplification process. The Amp arrives in it’s plain box – usually an exciting sign. Inside the box there is bubble wrapped AHA-120, a mini usb cable and four self adhesive stick on feet. Inside the bubble wrap bag with the amp is a silica gel sachet, included to prevent any moisture in the air from condensing and damaging the product. Removing the amp from the bubble wrap bag it becomes clear that extruded aluminium case is flawless with a soft anodised finish, and ultra fine print on both the front and rear panels. The company logo on the front panel is in colour and the serial number on the rear panel is engraved, which is a nice touch. The version I have is a product sample and is already burned in.
I can’t resist turning the large volume knob, switching the unit on revealing two things – a warm Amber glow from the LED and the silky smoothness with which the volume turns. The Aluminium case with soft anodised finish is solid and picking it up the unit weighs neither more nor less than expected – it is a little large though compared to most portable amps (26mm x 80mm x126mm, the uHA-120 is much smaller – 23mm x 52mm x 85mm) but still has a very small footprint when used as a desktop amp. Print work is detailed is flawless with all controls well labelled, panel fixings appear to be stainless steel. At the front, right to left, you have the chunky volume knob with accompanying Amber on/off LED, next the 3.5mm output then the input and finally a five-way selector nob for impedance matching your headphones. This feature is probably more accurately described as class A biasing level, most users would like to match current setting to their headphones, this is simplified by just providing a selector for selecting the amount of bias needed to maintain class A operation for a given headphone impedance. Without this feature the battery would apparently only last around 18 hours whereas now you can get up to 60 hours of battery operation when driving 600 ohm headphones. Round the back there is an engraved serial number, USB charging socket and red to Green Charge LED and two small charging operation switches for charging management with other USB devices. The AHA-120 contains a Vishay P11 potentiometer mounted on a solid ground plain PCB, low ESR Capacitors, Burr Brown Opamp to provide a FET input stage and Alps switches. The flat front panel sockets feel rather nice and connection seems very solid and reliable with a very positive feel to the connection.
The first device I connect to the AHA-120 is my iPod touch via an iBasso CB07 pure Oxy sealed LOD cable, I plug in the Beyer T1’s and turn the five-way switch to 600. Firing up the first lossless track, Radiohead – Pyramid Song, I am instantly impressed with the balance of weight and air, there is an instant feeling of synergy between amp and headphones. As the song unfolds I find myself closing my eyes and feeling my way around the stereo image. There is real texture to the sound which is vivid, heavy and fluid – detail is is apparent but subtle giving structure and very accurate movement to each instrument. The piano in this track is distractingly pretty and I am already excited to try plenty of other favourite music. There is a ton of headroom and I never get the white marker on the volume control much past 12 o’ clock.The iPod touch is surprisingly charged twice in two days before the amps lithium polymer battery runs flat, which I had not expected at all. It isn’t the best I’ve heard from the T1’s, but the iPod is the most likely culprit and I will put that to the test next. After a decent couple of hours with this initial setup I connect the AHA-120 to the analogue outs on a broadcast quality sound card (running .WAVs from a Mac Book Pro) and revisit the first track I heard. Within seconds I’m glaring at my iPod and shaking my head in disappointment as if it had just kicked a football through my kitchen window. This shows the pairing has real merit, as inferior sources are often shown up by a great headphone/amp combination. The sound is more lush with even more realistic texture and structure, solid and powerful but lighter, quicker. I run through a few classical favourites (this is, to date, the best I have heard Prokofiev’s Piano Concerto No2) and the first bad thing I think is when I realise that I have to give the amp back. It follows me everywhere with the iPod touch, great results with Ultrasone Pro 900, Beyer DT770 and DT880, Sennheiser HD650 and HD600 and fantastic in 32ohm mode with my Grado 325is, until sadly it has to go back. Just Audio have a balanced configuration ,using two AHA-120, which includes either balanced XLR or Jack output into the amps and a HD650 balanced cable. Justin expects Beyer T1 and Sennheiser HD800 users will be interested in a cable mod or replacement cable to use this configuration too.
The AHA-120 is very accurate but has a lush warmth which adds to its very real sound. It seemed to encourage the already super clean Beyer T1’s to find convincing sculptural depth in some quite difficult recordings. As promised Just Audio seem to have built a portable Class A which can contribute the power and finesse needed for high impedance, flagship model headphones.
Future Just Audio Projects
Just Audio have some exciting projects under way. They are currently designing a very forward thinking DAC which may be modular, new Balanced operation cables are available now with more cable variants to come and Balanced amps may eventually appear. Due to customer demand some iPod modifications may be added to their service repertoire and customisation of Just Audio amps will continue to be carried out for the best possible operation with specific headphones. Thanks to Justin for talking to me, the loan of the AHA-120 and for the use of the Photos.
Just Audio at Head-fi Meet
Just Audio will be attending the London Head-fi meet where you can try the AHA-120 and uHA-120 for yourself and pick Justin’s brain about his approach to Audio Design. He will be there with another of our favourite HiFi people, Mark Dolbear who will have the latest HiFiMan HE-5LE and HE-6 and Schiit Audio amps on display and for you to try.
More Information
More information on the full range of Just Audio Products can be found here.
