T Amp Triumphs - Two Small Amplifiers That Sound BIG!

XY DT-0118A Tripath Amplifier (TA2024 Chip)
Source: Dafang Logistics Limited, Hong Kong
Sugg. Retail: $49.95

Trends Audio TA-10 Ver. 1.1 Tripath Amplifier (TA2024 Chip)
Sugg. Retail: $189.95

Manufacturer: Trends Audio, Hong Kong, www.trendsaudio.com

These two little (easily handheld) amplifiers are recent successors in a category that has had budget-conscious audiophiles abuzz online for the past couple of years. Aaron reviewed the original Sonic Impact first-generation Tripath (T-AMP), and it is the most popular review we’ve ever published. There are now dozens of brand names from Hong Kong or South China using identical chipsets, the most recent being the Tripath TA2024, on which these two amps are based.

I took both to the island this July to audition in my 12-volt solar-driven cottage system. Now, in early August I can find no current listings for the XY  brand, but a multitude of other names are out there in cyberspace: HLLY, Indeed, Nonsuch, Topping, Gold or Golden, Lihao, Lepai, and Pop Pulse are just a few, with the original name that started it all, Sonic Impact, still out there. The Tripath design has been appropriated by such high end names as Bel Canto and Audio Research for their own designs based around the TA2024 chip. That must mean they sound good to some ears.

According to Wikipedia, “Class T…is an implementation of Class D amplifiers, but improves the control scheme to create more efficient and higher quality audio amplification.” “The two key aspects of this topology are that (1) feedback is taken directly from the switching node rather than the filtered output, and (2) the higher order loop provides much higher loop gain at high audio frequencies than would be possible in a conventional single pole amplifier.”

Specifications for these little amps are unusual for transistor types, in that instead of the hard clipping we normally associate with bipolar designs, we see progressively higher distortion figures with wattage. Though rated at 15 watts rms per channel, the rated THD is a scary 10% at 15 watts into 4 ohms and also 10% at 10 watts into 8 ohms, very high figures for a high fidelity component. But, wait, it’s not quite so bad, with 11 watts available into 4 ohms at .1%, and 9 watts into 8 ohms at the same distortion. In a practical sense, these little amps will look better the more there are, bi-amping an option with many speakers, but more on this later. And, certainly, we can see the efficacy of using these little amps with very efficient loudspeakers. The name Klipsch comes to mind.

Speaking of efficiency, these T amps are very much so, with a power efficiency of between 80 and 90%, from 3 to 5 times that of conventional amplifiers, which is one reason they are ideally suited to 12-volt battery-based systems. I immediately noticed this at the cottage, compared to my older Pioneer 30-wpc car amplifier. Not only did the T amps (individually) sound better than the aging Pioneer, but drew a lot less current from my battery system, with clean SPLs as high in level as I would ever listen. The speakers in that system are a pair of TEACs from a 300 Series system I gave to my daughter a few years ago with larger floorstanders. They’re very good, and showed it with the T amps, which I should describe in a little more detail.

The XY  is pretty basic, and black, with a mini-jack input, and tiny screw-tap speaker outputs. You can forget audiophile cables in either case, but I found some speaker cable with few enough strands to fit, and fed this T amp with an RCA-to-miniplug adaptor from my QED passive preamplifier’s RCAs. The more expensive Trends TA-10  is better fitted, with gold-plated RCAs, and 5-way shielded binding posts of the type found on higher powered amps, including my Bryston 3B SST at home. All these connectors and the 12-volt input take up pretty much all of the rear panel. The finish on the TA-10  is a nice silver front and grey case. Sonically, both T amps exhibited the same excellent characteristics, which I’ll elaborate upon shortly.

I didn’t bi-amp the two T amps at the cottage because the TEAC  speakers don’t allow it, but did later at home with the recently reviewed  ELAC BS 243  small monitors. In both cases, even one amp provided plenty of clean sound, with excellent dynamics, very low noise, but could sound a little strained when driven too hard. Watts are watts, and the more the better. The TEACs are closer to a 4-ohm load, and made the most of the T power, while the ELACs represent an almost pure 8-ohm impedance. As a result, the latter speakers were much more dynamic when passively bi-amped, the XY  on the treble, and the Trends driving the bass/midrange driver.

In this situation we have under $300 of amplification sounding like a lot more expensive gear. I’ve not been a fan of digital amplifiers in general, finding them rather sterile and etched. But not so here! These little buggers, within their limits, sound big and clean, with excellent bass, and a very lucid midrange, the top end sweet and open. With more efficient speakers, microdynamics are heard that add a nice sparkle to the sound; the ELAC pair, with its JET tweeter, is quite a nice match bi-amped, with the treble just slightly reduced using the XY  T amp’s level control. And the Trends TA-10  had more oomph and tightness in the bass in this configuration. Adding a Sunfire True Subwoofer below 50 Hz made the system sound very much like a full-size, full-range speaker system.

Finally, some words about power supplies: all T amps run on 12 volts, and 3-to-5 amps are preferred. At the cottage this was easily supplied direct from my solar-fed deep-charge battery, while at home I used a small AC/DC converter that was rated at 1 amp with excellent results, even with both T amps running at once when bi-amped into the ELAC speakers. For a permanent setup, I would want to add a better quality, regulated DC power supply of ample amperage.

The Trends came with an AC power supply, which failed immediately, while the much cheaper XY  had none at all, not even a cable with a car-lighter plug. Fortunately, I had two such cords in my collection. Some of the quite large brand-to-brand price differences do represent with-or-without power situations, so check carefully before you order one of these little amps. It’s also the case that very different levels of fit and finish are available, form the raw circuit board and chip to nice little packages like the pair represented here, so caveat emptor.

Even if you just want to experiment with T amps, it’s an affordable option, and a good bet for a portable system of good quality; you can even bolt each amp onto the back of a speaker and bi-amp each with the 2 T amp channels. Talk about instant nearfield monitoring!

I think that the T amp has matured to the point where it can be taken very seriously, with several different designs beyond the TA2024 also available. I’ve just ordered a TA2020-based 20-wpc (10% THD) version that includes bass and treble controls. For under $30USD shipped, it was well worth taking a flyer on. I’ll report back on that one soon. There’s also the TA2021 version with a headphone jack on the front panel.

In sum, these little wonders are, simply put, very good power amplifiers at prices from the many makers and sellers that range from great to amazing, the differences based around what is offered in each package. In an historical sense, these amps could be said to represent a throwback to the days when low-power (3-6 watt) tube amps were used in theatre and some home systems with large horn speaker designs. It’s odd and fascinating that technology can come full circle this way.

Andrew Marshall