Internally, the G109 differs from the G103 in some key areas. It features a higher spec toroidal transformer with a larger array of smoothing caps, a premium Alps RK27 pot, and offers three gain choices (-4, +8, +14 dB) instead of four. The business end consists of a classic NE5532 opamp driving a discrete diamond buffer made up of 4 transistors per channel. Output impedance is less than 0.2 ohms. Once again, this is a relatively simple design but very well executed.
These improvements pay dividends in terms of sound. We keep the excellent low frequency performance, which is actually subtly improved (especially with higher impedance headphones, at high volumes). We get a slightly improved, transparently clear midrange. But this time we get matching quality in the upper mids and highs---the G109 is agile, with transients being more accurately resolved. It's a very neutral sound, and since everything is on the same level it doesn't give that perceived "warmth" of the G103.
My favorite aspect of the G109 is its universal ability to drive pretty much any headphone in existence. Very short is the list of relatively affordable amps that can swing this much voltage into high impedance loads while delivering gobs of current into planar models (over 2000 mW at 50 ohms), with variable gain and an inky black silent background with even the most sensitive IEMs.
Of course, this is still a device built to a price point, and as such it isn't intended to be a statement product. Folks looking for really high end performance should be checking out gear from from
ECP Audio,
Apex Audio, or
Eddie Current, just to name a few. In comparison to its upscale Violectric V200 sibling, the G109 is less resolving and isn't as velvet-smooth up top. Nor does it capture that convincingly holographic "you are there" feel. But the V200 is twice the price, and has a host of improvements like double the output transistors per channel and much higher power supply voltage with more regulation. It's impressive that the G109 does so much with so little.
The Apex Butte is an excellent comparison for the G109. It costs about the same, and in many ways sounds about the same too. Once again the Butte suffers from having a lower quality volume pot, while the G109 has essentially perfect channel balance. From a usability standpoint, I like having the different gain options to play with. When using sensitive headphones, or especially IEMs, I always wish the Butte had more usable range in the volume---it gets really loud, really quickly. Aside from those minor issues, the Lake People and Butte have very few distinguishing sonic traits. I think I hear a touch more upper midrange accuracy on the G109, especially with higher impedance headphones, but the difference is fleeting.
Conclusions
The philosophy of headphone amplification, according to Lake People, is simple: high output voltage; high output power; high damping factor due to low output impedance; and low noise through low internal gain. These four essential ingredients are easy to describe but not always easy to achieve. With the G109, and to a lesser extent the G103, Lake People have accomplished those goals. In the process they have matched or even exceeded the already high performance of the Apex Butte, which is a very respectable accomplishment. I highly recommend each amp within their particular price points.
Destiny..