I recently got PR1 Pro and also AST. They are still quite new and just started to explore them. Here are some quick thoughts:
PR1 Pro - After seeing the graph of PR2 vs PR1 Pro I decided to go for PR1 Pro. I must admit I haver never had planar before. Out of box they sound very good. Sound is pretty well balanced, they have great bass and tonality. They have very clear highs but nothing harsh or piercy sounding. I like them a lot and they remind me my JD7 which are also fanstatic set. No problem with fit, built is great and the stock cable I am not going to use, trying different cables and I assume the pure copper would be the best fit for these.
One thing I noticed is that the bass is deep but also quite dry. Sub-bass is very nice but the mid-bass is slightly lacking. I am definitely going to add a bit of push with my EQ here. The mids are very clean, fantastic separation and imaging but they also sound slightly thin. Overall sound if beautiful and engaging but to my taste just a bit thin which I assume is due to the planar technology here. Another thing I noticed is that these do like a lot of power as I am using full gain with these (only set I have that is calling for it). Once they have enough power the sound is fuller more lively. Indeed these are very good set from KZ.
AST - I got them recently as I was looking for full BA set and after longer research I actually aiming for Penon Impact. They seem to be such great iem but way too expensive right now for me and when I first saw the AST in sliver / transparent shells ... wow, they definitely have the look and remind me that Impact a lot. Got them with new custom silver cable and right away pair them together. Out of box these sounded very odd and artificial like. There was no treble and sound was very bloomy like. Tried different settings, EQ but nothing worked, I decided to return them right away. Then I noticed the stock cable and I plugged that one in. Straight away I was shocked as the sound changed completely. It was like I changed the whole set and not just the cable. Suddenly there is this amazing clear sound with very deep and wet bass, mids full of details and body. After this I tried few more cables and to my surprise some of them worked nicely and some did not work well at all. I ended up with Tripowin Jelly cable and this one sounds the best from a small collection of cables I have.
The AST are really, really amazing set. Whatever I play sounds fantastic and they are almost perfect set to my ears. But as always there are couple of smaller issues I have with them, they are slightly dark and the upper treble need some EQ push from around 8000hz upwards. I adjusted my EQ and now they are correct to my ears. The second issue is with their size.. these are very big and barely fit my ears. There is slight discomfort but I hope my ears will adjust as I am not getting rid of these. I have also noticed that the sound improves with every passing day. I believe these need some proper burning time. I already had like 15 hours in but had to send them back for replacement as the company sent me black version and I really wanted to have the silver one. So, now here I am starting with my burning again :-/
I am yet to fully explore these but again what a fantastic product and amazing sound these have. I am listening to high quality audio for years and I know when something sound bad, all right, good, or phenomenal. And yes these AST do sound phenomenal at least with my setup... PC with EQ > K5 Pro > Tripowin Jelly cable = just superb.
I was listening to some audiophile recordings and out of nowhere some metal track was played. It was like somebody slapped me over my face. That sound... OMG.
I am not very much into metal and similar music but this sounded incredible. Right away I pulled out my Doom 2016 and Doom Eternal Soundtracks in FLAC and here I am listening to that music and writting this article literally having musical orgasm!
Cannot wait to fully burn these and then A/B compare them with my favorite set FH9.. that is going to be something special but lets wait couple of weeks for that.
I will definitely share my impression here.
Here is my conclusion.... The PR1 Pro - very good iem with excellent tonality, I like them a lot yet have to listen to them more (only got them few days ago).
The AST - what a killer iem with flagship sound, really there is not much more you can get from proper iems these days. If you like to spend your money wisely then get these and forget about the other expensive stuff everybody else is raving so much about mostly because they spent a fortune on them and now they dont want to admit some low budget iems can be right there on top with their special purchases. I might have small iem collection but I have listend to a many more expensive sets and set ups in my life. These deserve full attention guys. Cant believe they do not have any reviews on this website, at least I have not seen any... hmm.
Happy Listening
