I have order the SG1 from Massdrop and had enjoyed it for about a month. I have the RHA CL1 and I do not hear the problem of over piercing highs. Instead I hear extreme spacious and well focused vocals and positioning and layering of instruments. You need a desktop amplifier or a really good portable amp to control the high impedance earphone. I had been using an Acoustic Research M2 for more than 2 years and the warm Class A output of the M2 drives the CL1 nicely, even better with the Vorzamp Pure II+ portable amplifier. I found the SG1 very close in character to the CL1, but with only 30 ohm impedance, it is much easier to drive than the CL1. The SG1 is a monitor, that is, its design is more towards being pure and technical than being musical. That is probably due to the characteristic tone of the graphene membrane. It just honestly brings out each bit of sound frequency clearly in the music, without any coloring. The lows are very much extended with a lot of mid bass that gives one an energetic feel. The mids are clear, but a bit colder than CL1 and smoother, not as analytic as the latter. Perhaps I have been adapted to the very extended and metallic highs of the CL1, I found the highs of the SG1 a bit recessed and not smooth enough. That said, the soundstage and layering of the SG1 is typical of a very good dynamic driver. Depth is a bit deeper than the width, but the soundstage very holographic. To me, it is a good replacement for CL1 when I am on the go and do not want to carry an amp. However, it is very strange that even M2 is not able to control the bass of the SG in the same way it does well on the CL1. The M2 can bring out the mid bass of the CL1 without an amp, just not the deepest part of it. With SG1 however, M2 seems to be struggling to release the bass. When I added the Vorzamp Pure II+, everything is beefed up, with deep extension of the lows and drums strike with authority. The mids can never be said to be recessed. It is just smooth and transparent, and vocals sounds very natural. The highs are still a bit recessed as compared to CL1. With my LG G7+ thinQ, the sound is too bright as both LG and the SG1 have a slightly cool tone. Without activating the built-in amplifier in the LG, the bass is under delivered. My conclusion is that the SG1, regardless of its low impedance, still requires a powerful amp stage to drive the dual-coil dynamic drivers. The SG1 costs only a third of the CL1, what more can one ask for? The best thing that I like about the SG1 is that it is less analytical than the CL1 and work better than CL1 with badly recorded pop songs, or old classics, without as much roughness or harshness.
That is not the end of the story yet. I recently order a DIY Xsymphony cable using mixed bundled copper and silver wires for the SG1 and the improvement in sound is staggering. Now the M2 is able to bring out the lows and the mids are slightly thickened and sweetened, and highs are extended. The overall effect is like adding a tube preamp in the upstream. At less than half the cost of SG1, this is a very worthy upgrade and the SG1 sounds excellent with my LG G7 thinQ cell phone. I would suggest owners of the SG1 to upgrade the cable with a thicker copper core and some silver to give more meat to the highs. I have also auditioned the SG3 for a few days. I am a audiophile and to me, my initial preference leans more towards the SG1 after cable upgrade. The SG1 well worths much more than its asking price. While the Knowles BA drivers in the SG3 do sound musical (which also means mellow and a bit veiled in my book) compared to the SG, the spatial cue of the instruments and sense of reality of the soundstage for multi BA drivers does not come close to that of a well designed dynamic as good as that in the SG1. Considering that the SG3 costs twice as much as the SG1, and there are a lot of choice of iems in $the 300 range, I will try more options with the switches in the SG3 in the next few days to see if it will be a keeper for me.
