Following are my thoughts, after listening to the Jomo Audio Gran Tourer GT600 for a few days. The GT600 Gran Tourer Universal IEM is packed with 2 hybrid Dynamic Drive, 6 Balanced Armatures (Sonion) and Quad Electrostatic Drivers (Sonion). It made its debut towards the end of 2022. Two unique and special 10mm co-axial Dual-Diaphragm Dynamic Driver armed with Super Carbon Nanotube Diaphragm are housed in each shell of the GT600. The Dynamic Drivers are run by 2 Tesla coils and tuned for ultra low distortion. The 6 way crossover is meticulously designed by Joseph for delivering crispy and clean notes to your ears.
Specifications:
Unibody Forged Carbon Fiber Chassis (UIEM Only)
4 Sonion Electrostatics (Super High)
6 Sonion/Knowles Balanced Armature Drivers (2 Low-Mids, 2 Mid-Highs, 2 Highs)
2 Tesla Dynamic Driver with electronic tuned phase adjustment
10mm Co-Axial Dual Diaphragm (CADD)
Super Carbon Nanotube (SCNT) Diaphragm
6 ways passive crossover
4 sound bores
The research behind the GT600 is quite interesting as well. Joseph spent 7 years studying ear shapes to make a UIEM as close as possible to a CIEM. It has not been done by 1 or 100 earmolds but 1000’s of them to come up with a shape which makes the GT600 very comfortable and ergonomic for long listening sessions. Despite being packed by 12 drivers on each side and a complex cross over, they manage to be very comfortable for the user. Needless to say that the quality of drivers and tuning of the GT 600 along with its ergonomic fit is sure to give listeners an experience which should be expected for an IEM of this price.
The shell is made from Toray Carbon fiber, like my Road Bike but weaves in multi layups. This particular Carbon is super stiff, strong and extra light. The downside of using this process is that it can take up to 10 hours to make a single shell. The Carbon has to be impregnated with resin and that has to cure. Some processes in carbon need a oven and some even use blatters to keep the tubes open before they let the resin harden up.
Listen was done on HiBy RS8 on Medium gain to open up the IEM. Low gain didn’t give enough power to allow the dynamic drivers of the GT600 to open up. Certain Dongles, portable DACAMP would need to be set on High gain since not every equipment has 3 gain settings. These need to open up to fully deploy their musicality and the dynamics as well. For settings on my HiBy RS8 MSEB is off for now, you may tweak it further to your liking. The only 2 Plugins that were active were Convolution and the MasterMind plugin. Convolution was set with the BRIR20231115 file from Joe Blogs of HiBy. The MasterMind plugin was set to my preferred Tube setting which give a richer and warmer tone that is typical for tubes.
There are 2 cable options. You can either order it with the Adrenalin Mk and the upgraded version Adrenalin MK2. Both are available in 4 and 8 wires options. This cable does not have to be “rolled”. It works perfectly! You get a fully working pack when you order one. The eartips are a personal preference, Jomo provide wide cyclone bore and double flange tips. I stick to my Whizzer ET100 easytips since they are super soft and fit my narrow ear channels. Yes, I'm using Small as tips. I tried using Penon lacquer but the silicon used was a little too hard for me for long listening sessions.
Tone: The GT600 was not overly thick on Low gain, Once I switched it to Medium gain, the Dynamics starting to open up and started to thicken in note weight, but it is far from overdone. The general Tone and Timbre are spot on in terms of realism. Vocals and Guitars both sound overwhelmingly natural and real then stylized.
Sub Bass: The bass hits were nice, clean, not over pronounced, just enough to make you start bumping your head in some of the bassier songs. Like you can have in some EDM song where you start tapping your hand or your feet on the rhythm of the beat.
Mid bass: Found them ai little more pronounced. but that might be due to genre choice; some genres use more of the mid bass then the sub. Both rap in rock, even metal; the mid bass hits were nice in texture and clean. It also gives a sense of organics back to the male voices that can go deeper than normal.
Lower mids: The lower mids string like you can have on a bass guitar and even on an acoustic one, super clean, they were not lost in the mix. They were nice, clean and easy to follow. Even Cello, oh man how nice!! In Hell I'll Be In Good Company by The Dead South and even some more folkish songs by Mumford and sons.
Mids: The mids were really nice; they were not overcrowded like you can have at some times. They sounded open enough for every instrument to shine and bring it across in a very beautiful and natural way. Even in busiet racks like Through Fire And The Flame by Dragonforce, a very fast track, had no problems controlling the busy & speedy parts.
Upper mids: The pinna gain I felt was not that sharp, so people who might have a problem with this kind of stuff well this one is smooth sailing even in the tracks from an artist I know who has a harsh voice on most IEM’s this was really not an issue here on the GT600. The artist I'm hinting at is Tourist Le Mc. Upper snare instruments like a Harp and Violin were very nice, neither sharp nor harsh but natural overall. I even heard the reverb that the guy was going for. Vivald - The 4 Seasons more specifically the Summer part I got was quite amazing to listen to.
Vocals: buttery smooth both male and female; In some acoustic tracks one can actually feel the emotions that the artist wanted to lay in the song. In the Sound of Silence by Disturbed, David Draiman has a magnificent voice in that track. One More Light By Linkin park, sounds quite emotional as well.
Treble: nice and airy, it sounded open and wide. It kept the whole stage open to let the other regions shine in their own way without missing the little nuances and details to the mix. I'm very impressed to be honest.
Technicals: Well what is there so say, it is very well done the layering is fantastic! The image of the music playback is organic and not artificial. The driver coherence is perfect. I didn't find a single note that was out of place. Bundling all of this with a proper cable out of the box is an icing on the cake. Even though I didn't have to tip roll much, they didn’t make much of an impact on the image or the sound quotient itself.
I have to say. I was not expecting this! To be fair, Joseph and team have done a fantastic job on this masterpiece. Not only sound wise but also in using his engineering background to make a shell fully out of carbon. Highly skilled and Patient with their work is what I just say to Jomo Audio Team. They made the drivers sound effortlessly playing together in perfect harmony without being against or over each other.
A big thank you again at Jospeh Mou of Jomo Audio for the loaner.
Joy of Missing Out
Specifications:
Unibody Forged Carbon Fiber Chassis (UIEM Only)
4 Sonion Electrostatics (Super High)
6 Sonion/Knowles Balanced Armature Drivers (2 Low-Mids, 2 Mid-Highs, 2 Highs)
2 Tesla Dynamic Driver with electronic tuned phase adjustment
10mm Co-Axial Dual Diaphragm (CADD)
Super Carbon Nanotube (SCNT) Diaphragm
6 ways passive crossover
4 sound bores
The research behind the GT600 is quite interesting as well. Joseph spent 7 years studying ear shapes to make a UIEM as close as possible to a CIEM. It has not been done by 1 or 100 earmolds but 1000’s of them to come up with a shape which makes the GT600 very comfortable and ergonomic for long listening sessions. Despite being packed by 12 drivers on each side and a complex cross over, they manage to be very comfortable for the user. Needless to say that the quality of drivers and tuning of the GT 600 along with its ergonomic fit is sure to give listeners an experience which should be expected for an IEM of this price.
The shell is made from Toray Carbon fiber, like my Road Bike but weaves in multi layups. This particular Carbon is super stiff, strong and extra light. The downside of using this process is that it can take up to 10 hours to make a single shell. The Carbon has to be impregnated with resin and that has to cure. Some processes in carbon need a oven and some even use blatters to keep the tubes open before they let the resin harden up.
Listen was done on HiBy RS8 on Medium gain to open up the IEM. Low gain didn’t give enough power to allow the dynamic drivers of the GT600 to open up. Certain Dongles, portable DACAMP would need to be set on High gain since not every equipment has 3 gain settings. These need to open up to fully deploy their musicality and the dynamics as well. For settings on my HiBy RS8 MSEB is off for now, you may tweak it further to your liking. The only 2 Plugins that were active were Convolution and the MasterMind plugin. Convolution was set with the BRIR20231115 file from Joe Blogs of HiBy. The MasterMind plugin was set to my preferred Tube setting which give a richer and warmer tone that is typical for tubes.
There are 2 cable options. You can either order it with the Adrenalin Mk and the upgraded version Adrenalin MK2. Both are available in 4 and 8 wires options. This cable does not have to be “rolled”. It works perfectly! You get a fully working pack when you order one. The eartips are a personal preference, Jomo provide wide cyclone bore and double flange tips. I stick to my Whizzer ET100 easytips since they are super soft and fit my narrow ear channels. Yes, I'm using Small as tips. I tried using Penon lacquer but the silicon used was a little too hard for me for long listening sessions.
Tone: The GT600 was not overly thick on Low gain, Once I switched it to Medium gain, the Dynamics starting to open up and started to thicken in note weight, but it is far from overdone. The general Tone and Timbre are spot on in terms of realism. Vocals and Guitars both sound overwhelmingly natural and real then stylized.
Sub Bass: The bass hits were nice, clean, not over pronounced, just enough to make you start bumping your head in some of the bassier songs. Like you can have in some EDM song where you start tapping your hand or your feet on the rhythm of the beat.
Mid bass: Found them ai little more pronounced. but that might be due to genre choice; some genres use more of the mid bass then the sub. Both rap in rock, even metal; the mid bass hits were nice in texture and clean. It also gives a sense of organics back to the male voices that can go deeper than normal.
Lower mids: The lower mids string like you can have on a bass guitar and even on an acoustic one, super clean, they were not lost in the mix. They were nice, clean and easy to follow. Even Cello, oh man how nice!! In Hell I'll Be In Good Company by The Dead South and even some more folkish songs by Mumford and sons.
Mids: The mids were really nice; they were not overcrowded like you can have at some times. They sounded open enough for every instrument to shine and bring it across in a very beautiful and natural way. Even in busiet racks like Through Fire And The Flame by Dragonforce, a very fast track, had no problems controlling the busy & speedy parts.
Upper mids: The pinna gain I felt was not that sharp, so people who might have a problem with this kind of stuff well this one is smooth sailing even in the tracks from an artist I know who has a harsh voice on most IEM’s this was really not an issue here on the GT600. The artist I'm hinting at is Tourist Le Mc. Upper snare instruments like a Harp and Violin were very nice, neither sharp nor harsh but natural overall. I even heard the reverb that the guy was going for. Vivald - The 4 Seasons more specifically the Summer part I got was quite amazing to listen to.
Vocals: buttery smooth both male and female; In some acoustic tracks one can actually feel the emotions that the artist wanted to lay in the song. In the Sound of Silence by Disturbed, David Draiman has a magnificent voice in that track. One More Light By Linkin park, sounds quite emotional as well.
Treble: nice and airy, it sounded open and wide. It kept the whole stage open to let the other regions shine in their own way without missing the little nuances and details to the mix. I'm very impressed to be honest.
Technicals: Well what is there so say, it is very well done the layering is fantastic! The image of the music playback is organic and not artificial. The driver coherence is perfect. I didn't find a single note that was out of place. Bundling all of this with a proper cable out of the box is an icing on the cake. Even though I didn't have to tip roll much, they didn’t make much of an impact on the image or the sound quotient itself.
I have to say. I was not expecting this! To be fair, Joseph and team have done a fantastic job on this masterpiece. Not only sound wise but also in using his engineering background to make a shell fully out of carbon. Highly skilled and Patient with their work is what I just say to Jomo Audio Team. They made the drivers sound effortlessly playing together in perfect harmony without being against or over each other.
A big thank you again at Jospeh Mou of Jomo Audio for the loaner.
Joy of Missing Out 
