I agree with the suggestions to get to a meet to listen to the gear that you want to buy. Only you can decide what is better and whether it's worth it. That said, I think you should consider the Audio GD Master 9 headphone amp. Why? IMO, it offers as good or better performance than the other amps that you're considering.
The M9 outputs a full 9 watts of class A power where as the Liquid Gold only outputs 25% of its 9 watts or 2.25 watts in class A power. The M9 has more versatility than other 2 amps because it can be used as a preamp in a speaker system. I believe the M9 has more input options than the other 2 amps. Also the M9 is the only one of the 3 amps that offers a remote control and personally I find it very useful.
Comparing the M9 to the Studio Six, the M9 is fully balanced where as the S6 isn't balanced. The M9 outputs 9 watts into 40 ohms where as the S6 outputs about 1 watt. The higher power output of the M9 can be significant when driving some of the hard to drive orthos like the LCD 2 and 3 or the HE6. Most S6 users will spend a considerable amount of time and money tube rolling. For some, tube rolling is fun but for others it's very time consuming and sometimes there's no end to it.
I haven't even brought up the fact that the M9 costs less than half of the other 2 amps because I wanted to show that it plays on a level field with the other amps regardless of cost. The main difference in cost is the fact that the M9 is made in China where as the other two are made in the USA. If the M9 was made in the USA, it would probably cost more than the other two. The M9 is built like a tank weighing in at about 35 lbs versus the Liquid Gold at 12 lbs and the S6 at 27 lbs. All this wouldn't mean a thing if the M9 didn't sound good. I think the M9 sounds great and especially well with the LCD X. I listen to that combination more than my Stax rig. Don't just take my word for it, go over to the Master 9 thread and read other user comments. Many M9 owners use the LCD X and I think it's a synergistic combination. YMMV. Good luck in your search.
The M9 outputs a full 9 watts of class A power where as the Liquid Gold only outputs 25% of its 9 watts or 2.25 watts in class A power. The M9 has more versatility than other 2 amps because it can be used as a preamp in a speaker system. I believe the M9 has more input options than the other 2 amps. Also the M9 is the only one of the 3 amps that offers a remote control and personally I find it very useful.
Comparing the M9 to the Studio Six, the M9 is fully balanced where as the S6 isn't balanced. The M9 outputs 9 watts into 40 ohms where as the S6 outputs about 1 watt. The higher power output of the M9 can be significant when driving some of the hard to drive orthos like the LCD 2 and 3 or the HE6. Most S6 users will spend a considerable amount of time and money tube rolling. For some, tube rolling is fun but for others it's very time consuming and sometimes there's no end to it.
I haven't even brought up the fact that the M9 costs less than half of the other 2 amps because I wanted to show that it plays on a level field with the other amps regardless of cost. The main difference in cost is the fact that the M9 is made in China where as the other two are made in the USA. If the M9 was made in the USA, it would probably cost more than the other two. The M9 is built like a tank weighing in at about 35 lbs versus the Liquid Gold at 12 lbs and the S6 at 27 lbs. All this wouldn't mean a thing if the M9 didn't sound good. I think the M9 sounds great and especially well with the LCD X. I listen to that combination more than my Stax rig. Don't just take my word for it, go over to the Master 9 thread and read other user comments. Many M9 owners use the LCD X and I think it's a synergistic combination. YMMV. Good luck in your search.