Thus far all of the reviews I’ve done here have been on readily available products. Most of them were purchased by me and reviewed for fun, but there have been a few loaners sent to me just for review, and even the occasional free sample. With all three of those types, there is still a place you can go to find and buy your own, either online or in a brick and mortar store. I’ve not had the pleasure of being sent a development prototype, and have never been included in a beta testing program. I’ve always thought those sounded fun but at the same time strange because the final product could differ wildly from the one you had been dealing with, therefore possibly making your impressions irrelevant to potential purchasers of the commercial model.
In this case, a friend who was overseas at the time sent me this product as a gift. He knows I’m into headphone audio and figured I might like it. He didn't know much about it and refused to tell me the price. Judging from the box I figured it looked like a commercial product that would be sitting on a shelf for sale. I proceeded with listening for the review as I normally would. Later I looked online and discovered that there is very little web presence for this thing. The company has a website with some decent info, which I had to use translation to read of course, but there doesn’t seem to be any places selling it, or users using it. I don’t know if that makes my review irrelevant, but I’ve already done the listening and taken the notes so I might as well post it.
The product in question is the TCG T-Box. It’s a portable headphone amp of very small proportions; one of the smallest I’ve seen aside from the “ultra portable” class which includes the Fiio models, the iBasso T4, the GoVibe Derringer, and a few others. Since it was given to me as a gift I have no idea what the selling price might be. I don’t get the impression that it is meant to be an all out high end unit, but based on the build quality and packaging I don’t think it is a super low budget item either. If anyone has any further information about it, feel free to post in this thread. You can see more about it on the manufacturer’s website: www.tcgcn.com You’ll need to use google translate or some other service, unless you know how to read Chinese (or just like looking at pictures).
I’ll begin by listing the specs as posted on the manufacturer website. I’ve rewritten and paraphrased a lot of it to make it easier to understand.
*Texas Instruments TPA152 amplification chip
*Elna and Ero capacitors
*High capacity lithium-polymer battery (700mA)
*Linear Technology LTC4054 precision charging controller with smart charging circuit voltage regulator
*Maximum output 100mW + 100mW
*Capable of driving 16-400ohm loads, optimized for 16-64ohm loads
*Harmonic distortion: THD+N <0.001%
*Signal to noise ratio: 105dB
*Channel separation: 102dB
*Frequency response: 10-100kHz/1dB
*Battery life: 50-80 hours of use, 200 hours of standby
*Weight: 100g (including battery)
Charging is done through an included cable. One end goes into the T-Box, the other end to any standard USB port. An LED on the rear indicates charging status. On the front panel you find a fairly straight forward setup with a power switch, volume knob, 1/8” jacks for input and output, and an LED indicating power is on. There’s nothing really unique or special about the design or the specs except for the fact that size is on the smaller end of the spectrum and battery life is on the very high end.
No surprises here; build quality on the T-Box is pretty good if not outstanding. It looks like it could easily pass for an iBasso or RSA amp if you didn’t know any better. It has nice tight panel gaps, and a quality feel on the power switch and volume knob. Even the graphics printed on the case, while somewhat more simplistic than the RSA designs, are well done. My only minor complaint is the choice of input and output jacks; they remind me of a cheap PC soundcard with their pinkish color. Indeed, the TCG website claims they are “Foxconn professional audio jacks”, and Foxconn is primarily a manufacturer of PC motherboards. I have no issue with the functionality of the jacks, as they feel solid when plugging in a headphone. My problem is purely a matter of aesthetics. On the TCG website, they show pictures of the T-Box with different color jacks: one has green jacks, which still reminds me of a soundcard and still doesn’t match the otherwise nice looking case. The other uses what appears to be a much more standard looking shiny silver/chrome type of jack, and I find it much more appealing. I’m hoping that version is an updated model as I think it would be universally preferred to the pink or green options. I've included some pictures from their website Other than that the choice of wording in the slogan: “Yours Audio Dreams” is kind of odd but not a big deal. The large yellow warning sticker appears to be easily removable, although I have not yet done so.
In actual operation, the T-Box has fairly good quality as well. I get a very minor channel imbalance at barely audible volume, and that only when using my most sensitive IEMs. Once I turn it up to a reasonable but quiet listening level things seem very nicely balanced, so I don’t really consider it an issue. Adjusting the volume does not give any static or noise. There is very little hiss when used with the ES3X (my most hiss inducing IEMs), and again once reasonable listening levels are achieved it is no longer an issue.
The T-Box comes in a retail-worthy box, and has some fairly nice accessories bundled with it. Inside the box we find expected items like the amplifier itself, the charging cable, and a user manual. What I wasn’t expecting was a very nice storage pouch, and an even nicer compact mini to mini cable. I’ve had various headphones and other gear that included some type of storage pouch, and they were almost universally worthless. This is the first one I’ve seen where it is nice enough to make me actually want to use it. And the included cable, listed as being made of “single-crystal copper”, is of high quality with Pailiccs connectors and nice black nylon sleeving. It looks like something that would sell for $20-30 on eBay all by itself (and in fact I just stumbled upon a website selling a nearly identical cable for $35). The website lists these as “promotional gifts” and implies that there is only a limited amount being included “while supplies last”. I have no idea how many they have to bundle, but I do think the overall package would go from very nice to merely acceptable if they didn’t include those items.
One of the above mini to mini cables cost me about $40. The other was a free pack in. If I hadn't already told you it might be hard to guess which was which.
This is the associated equipment I used for evaluating the TCG T-Box.
SOURCE: Sansa Clip+, Sansa Fuze with modified Griffin Power Dock (line out) or Fiio L6 LOD or straight from headphone jack, QLS QA-350 player, dedicated music server fronted by a Squeezebox Touch
DAC: Hot Audio DAC Wow, Audinst HUD-mx1, QLS QA-350 DAC section, Anedio D1
HEADPHONES: Ultimate Ears Super Fi 3, Kenwood KH-K1000, AKG K701, 1964 Ears 1964-T, Sennheiser HD600, Grado RS1, Fischer FA-003, Monster Turbine Pro Copper
These are just the impressions of one guy. I do these reviews for fun, not profit, and I don't claim to be any special authority. Many people have agreed with my assessments of other gear but some have also disagreed, and I totally respect that. We all hear differently on a physical level and we all have different preferences as well, so I think it almost impossible for one person’s impressions to apply to every other person. As with all my reviews, I hope you enjoy reading them and I hope they help our hobby to some extent, but I don't pretend that they are anything more than my opinion.
I feel it necessary to admit that I’m not an expert in portable amps. Over the years I’ve owned a Headamp AE1, RSA Hornet and SR71, Vivid Technologies V1, Qables iQube, Go-Vibe V6, and a few home made CMoy type portables. I’ve also spent time with loaners of the iBasso D10 and the Leckerton UHA6S. I feel like I have enough experience to accurately review this amp, but I readily admit there are plenty of folks around this forum who are much more “in the know” about these types of things.
After burning in the T-Box for 100 hours or so I started carrying it around with me in my portable setup. I initially used it with the 1964-T custom IEMs, which are fairly neutral in presentation and thus good for comparisons. Initially I didn’t notice a huge difference compared to the Sansa Clip+ I had been using. I thought it sounded nice and clean, with nice grain free highs and good impact in the bass. But this is my general view of the sound straight from the Clip+ anyway. Only after using the T-Box for a while and then taking it out of the chain did I notice that it was actually a decent step up from the Sansa’s amp section. In comparison, the Clip+ alone sounded slightly congested and closed off. It also seemed to flatten the dynamics a bit, which made the music less engaging. I’ve always been satisfied by the sound of the little Clip, Clip+, and Fuze (which sound identical in my opinion) but I have to admit once again that a quality portable amp can take things to another level.
Over time I began to get more of a handle on the sonic characteristics presented by the T-Box. It seemed to be fairly transparent, with clean and clear highs, smooth inviting midrange, and well defined lows. Soundstage performance was reasonable, with nice width and a decent amount of depth. Overall it is a fairly high performance little amp with no major defining sound signature of its own. If I had to pick an area where it deviates just a little from complete neutrality, I’d say it was a little bit relaxed in the bass department compared to some of the other portables I’ve owned. There’s not exactly a shortage of it, and it is certainly tight and controlled. But it just doesn’t quite have the same grunt as some others, and doesn’t grab your attention as much. I seem to remember my old Headamp AE1 and RSA SR71 having similar low end performance, compared to the Hornet which was more prominent. This isn’t to say it is bad…. In fact it may be more technically correct (but maybe less fun) than the Hornet or similar amps. Another area where I thought it was slightly relaxed was the upper midrange/lower treble area. Here again, the Hornet had a bit more energy, along with the Vivid V1, which makes them seem more forward and exciting but also sometimes fatiguing. The T-Box reminded me of the Leckerton UHA-6S that I enjoyed so much; both lack just the last bit of sparkle but retain good detail and air, and are rather forgiving of poor recordings. The Leckerton remains a step above but the T-Box trails surprisingly close in this area.
So basically what we have here is a fairly balanced but slightly relaxed and polite amp, without any overbearing bass or glaring highs. Mids are a strong point and they deliver with a smooth, open clarity that is almost surprising coming from such a little box. They aren’t quite on the level of some of the best I’ve heard but certainly follow in the same tonal footsteps as the SR71 and the iQube. It’s hard to describe, but when I say relaxed I don’t mean the usual warm syrupy type of sound where bass is huge, mids are rich, and highs are rolled off. With the T-Box it’s more a case of relaxed as in it focuses on the all important midrange, where the “meat” of the musical content lives, yet doesn’t kill the listener with excruciating detail. That was one thing I didn’t always like about the iQube; I felt like half of my music collection was unworthy and couldn’t stand up to its scrutiny. The T-Box is more forgiving in that aspect, although this of course means a diminished capacity as far as ultimate detail. Still, there is plenty to be had here, and I really enjoyed the overall presentation.
Since this is a fairly neutral amp, it doesn’t do much to change the core sonic signature of the headphone that you pair it with. I’m always amused when I hear from someone who has a headphone like an Etymotic ER4S or an AKG K701 and wants to use an amp or DAC to turn it into a Sennheiser IE8 or Denon D2000. If you desire a fundamentally different sound, no upstream components in the world are going to accomplish that for you; just buy new headphones! That being said, I do believe that some components either match or don’t match certain headphones according to their combined character. The TCG T-Box will generally work well with most headphones provided that you don’t expect it to majorly alter the final sound.
From a power standpoint, the little T-Box is not on the same level as some of the beastly portables being put out by iBasso and RSA these days. But I found it more than sufficient for driving any IEM I tried, and even some full size headphones within reason. It drove my AKG K701, Fisher FA-003, Grado RS1, Lawton LA7000, and Kenwood KH-K1000 to earsplitting levels. Note that these are all within the recommended range of 16-64 ohms. Trying out a 300 ohm Sennheiser HD600, the result was still loud enough, but I really had to turn the volume knob to get there. Using a really low efficiency Orthodynamic headphone didn’t turn out so well; acceptable for casual listening but clearly running out of juice. But for the on the go listener who occasionally likes to use full size headphones at home, the T-Box did an admirable job. More difficult models like the K701 obviously did not achieve their full potential, but were definitely listenable and enjoyable. I especially liked how it did driving the big Kenwood K1000. These are severely underrated headphones in my book and the T-Box allowed them to really shine, making for a much better pairing than when I used my Vivid Technologies V1 portable amp.
As I mentioned before, I don’t have vast experience with portable amplifiers. It doesn’t make sense to compare the little TCG to any of my home amplifiers, so my direct comparisons were limited to the Vivid V1 and the built in amp section of my QLS QA350 player.
I don’t know the technical specs, but the Vivid seems to be the more powerful unit, and pairs quite well with the Sennheiser HD600 or even the 600 ohm AKG K240DF. Aside from that the Vivid also has a more forward and energetic presentation which is very different from the polite nature of the T-Box. The Vivid can often make things sound better than they really should, but in exchange can absolutely murder some recordings. The TCG is more true to the source, giving you the basic facts of the recording in a pleasant if somewhat uneventful manner. The Vivid takes the lead when it has a synergistic pairing, such as the Sennheiser HD600 or Monster Turbine Copper. But in other cases the TCG outperforms it with a more honest representation. It really comes down to preference though, since we are dealing with 2 very different sounding amps.
I enjoy the built in headphone amp section on the QLS QA350. It is clean and fairly neutral just like the TCG. The differences here are not massive, but I can confidently say that the TCG is a decent upgrade. It sounds less grainy in comparison, which results in a more liquid sounding midrange (but not overly so). It also has a more open feel to it that lets the music shine through more clearly. I suppose one would hope that a dedicated amp would be superior to a built in amp, but there’s no guarantee of that. However, in this case it does seem to be true.
It’s difficult to compare the other portable amps I’ve owned, since direct A/B listening is usually the best way to note differences. Going by memory I’d say the TCG is an improvement on the several CMoy amps I’ve built, and I think I prefer it to the Headamp AE-1 and the Go-Vibe V6. It isn’t quite on the level of the RSA Hornet, SR71, or iBasso D10, and is significantly inferior to the Leckerton UHA-6 and the iQube. Again, this could just come down to my preference for the sound signature, and I think all of them were pretty solid performers (with the exception of my first CMoy build which was too noisy).
I realize that this little amp is not going to set HeadFi on fire with excitement. I don’t know if the general readership here on HeadFi will even be able to buy the TCG T-Box. If it does get picked up by a distributer, I hope they keep the price well under $200. Past that point I don’t see it competing with some of the iBasso offerings, or my personal favorite the Leckerton UHA-6. But the farther south the price goes the more solid my recommendation would become for this little amp. It’s got a very enjoyable sound, works well with pretty much every headphone you would reasonably expect it to drive, has an extremely long battery life, and is generally built quite well. Any portable amp that satisfies all of those criteria gets an easy “thumbs up” from me. The icing on the cake is the bundled premium mini to mini patch cable, which is something that most users would be spending another $20-40 on anyway.
Looking over the TCG website I see that they offer several variations of their compact desktop amp called the T1, for a total of 4 products. Based on my experience with the T-Box, I would love to see them bring a few more designs to the market. In my opinion you can never have too many companies offering quality audio gear at (what I assume will be) low prices. If anyone has any further info about the company or the products, please help me out by posting it in this thread.
Edited by project86 - 3/23/11 at 9:10am