Optima No. 6 GCHT 24K Gold and Carbon HT Guitar Strings Full Set
[NO6 GCHT]

The price is high but the quality is too. I have a Richard Howell Cedar Top (Fleta style bracing) and these strings are breathing a different life into my guitar. They make my instrument sound clearer, more sustained and the volume has increased. The sound of my guitar has now swung further towards the timbre of the strings and somewhat away from the timbre of the body as these strings are robust and quite loud. What I like about this is that it is significantly easier to play un-amplified to an audience. The audience can hear what I am doing more clearly and the tension balance between the strings is so accurate that individual voices within chords sound clear and are easy to make melodic.
I was using a variety of strings on this guitar before: Luthier 50, D"Addario LP & Carbon combinations (I just went through a stringing spree and shot 15 videos with different sets on my guitar to find the individual strings Iliked the most on my instrument) and I got my ideal set worked out. Now that I have tried these Optima Gold I am not so sure anymore :( ;) $$ Oh well, Shopping time!

Here are some key points about these strings:
Balance of the complete set: Excellent - couldn't be happier with the pressure gauge of all these strings, the most balanced tension I have found yet and it does make a difference to how hard I work when I am playing!

Timbre of the trebles:
A very slight metallic sound to the carbon E but overall the best Carbon E I have found, the B is a bit more dull compared to the E and sometimes needs the tiniest bit more nail in my technique to match sequences between both strings but as for cross string melodic work these 3 work very well indeed. The 3rd string is a bit of a problem but only in terms of timbre as it is the darkest sounding string on the set - but it doesn't sound thudding at all, it sounds mid range and 'heavy' and it carries a lot of weight musicially (so it's not all that bad and I have grown to like it very much, certainly my second favourite 3rd string [just behind D'Addario 'coffee' carbon 3rd]).

Timbre of the basses:
At first I thought the fact they were gold plated was a gimmick and even one of my students remarked that the basses looked like they were from a cheap tacky string set but to be honest the sound of the basses blew him away and he was very impressed and so was I. I think these are the best basses I have ever played, better than the delightful (but fragile) Luthier, D'Addario Carbons and Silvers, Savarez and Hannabach. They are so meaningful when they are played and they really 'say something musically' even as a chord they are so cohesive as a triad (Barrios La Catederal Mv. II Bm Triad on 6,5,4 strings) yet each string can be heard in its own right.

The trade-offs of these strings (some easy 'squeak' on the basses & darkening treble timbre from strings 1 to 3, and a tacky [but shiny] look) are utterly meaningless in the light of their benefits (supreme tension balance across the set, bass clarity & timbre to die for, stunning levels of sustain across all strings, the volume to play acoustically and get the musical message across to the audience). I would like to continue using them for my future live guitar work.

After playing various strings types by various brands over a decade I can honestly say that these are the most premium feeling and most balanced strings I have played.