FatFreq Grand Maestro

FatFreq Grand Maestro Universal
$2729.00 usd retail (MusicTeck)
$3599.00 sgd retail (FatFreq direct)

FatFreq doesn’t specify driver counts, or other specs like frequency response, impedance, sensitivity, etc.
What is known is; Tribrid technology, Dynamic Driver, BA driver(s), Quad EST drivers.

Preamble:
Shout out to Andrew and Grace at MusicTeck for the always awesome customer service and prompt shipping.
Also to Ben at FatFreq for patiently answering my numerous queries.
(At time of posting MusicTeck shows FF Grand Maestro as an in stock item)


- Tuning Switch:
There is nothing subtle about the tuning switch.
The change in sound signature is quite significant and noticeable.
In the Vocal boost ON position, mids and vocals are very much prominent and forward, very clear and detailed.
Head stage is clear and open.
In the Vocal boost OFF position, mids and vocals loose prominence and become somewhat recessed. They also loose some clarity and detail.
The sound signature becomes more balanced, and overall warmer.
Head stage closes in a bit.

The vocal boost switch is positioned on the top of each IEM,when positioned in ear, making it easily accessible.
The switch is not recessed, the pin protrudes out of the shell a couple mm (1/16 inch).
This is both a blessing and a curse.

The non recessed design facilitates changing switch positions on the fly without removing and reinserting the IEM each time.
But, the switches don’t have much resistance to movement making it very easy to reposition them unintentionally. I have developed a habit of checking switch position every time I put the IEM’s in my ears, or, if I reposition the IEM while listening.
Also, the switch pins are square with angular sharp corners that sometimes contact my ear, it is unpleasant when this occurs.

I can listen and enjoy the GM in either switch position, but have a strong personal preference for the vocal boost position. I generally like a more forward and energetic mids and vocal presentation, provided it’s not over emphasized.


- Build and Fit:
Build quality of the all resin shells appears to be excellent. The faceplate seam is expertly finished and invisible.
There is a small vent hole in the shell, presumably for the dynamic driver. And, of course, the large vent hole in the faceplate to facilitate the NOAH tuning modules.

The nozzles have a flange molded into them and I find they hold ear tips securely.
The nozzles have a semi custom shape, and reach deep into the ear canal.
I typically like a deeper fit, it often allows me a wider selection of ear tip options and, I have fit issues with short nozzles. On the Grand Maestro however the fit, for me, is a bit too deep. They reach into the area of my ear canal where it narrows a lot, and full insertion causes me almost immediate discomfort regardless of ear tip selection.

Fit is of course very personal, hopefully my ears are the exception, and fit won’t be a challenge for most people.
I’m having good success with larger sized Moondrop Spring, and Sedna Xelastec tips that seal and anchor well closer to the outer portion of my ear canal. The IEM’s protrude from my ears a bit more, but the fit is comfortable and the IEM’s stay in place and maintain a good seal.



- Tuning Modules.
There are currently two NOAH modules available, Black and Blue.
The Grand Maestro ships with the Black nozzles, the Blue modules (and future module releases, assuming there are more under development) are purchased separately.
I just received the blue modules a few days ago and I’m initially quite pleased with the alternative sound signature offered.

Frequency graphs are not yet available for reference and I’m not set up to graph. So this evaluation is based on my hearing.
Individual experience may vary.
** Edit. FR Graph added. Courtesy The Tone Deaf Monk.

The Black modules offer a sub bass boost in the 20-40Hz range, that carries into 40-160Hz lower bass band.
Bass is more boomy/thump in nature.
Resonance doesn’t decay quickly and carries through the head stage.
The black module also offers the most ambient noise suppression.

The Blue modules have less sub bass boost. Still excellent sub bass extension, but the 160-300Hz upper bass band is less veiled by sub bass and bass is fuller/tighter with resonance decaying more quickly. Less sub bass presence throughout the head stage.
The blue module offers good ambient noise suppression, but less than the black nozzle.

- Equipment:
-Astell and Kern Kann Max, mid gain, 4.4mm balanced out.
-FatFreq Grand Maestro aged 100+ hrs.
** (Vocal Boost Switch ON position)
-Stock modular Copper/Silver plated copper hybrid cable. 4.4mm termination.
Sedna Xelastec ear tips size M for a mid point nozzle insertion depth.

- Sound:
Black Module
Bass has a sub bass boost and focus that is very well implemented. Sub bass extends low and lower bass is boomy with some thump. Mid/upper bass is somewhat overshadowed by the lower bass range.
An example is “Metallica - Now That We’re Dead”. Toms in the opening drum volley exhibit more woof than punch.
Lower mids are recessed.
Mid range is clear and open.
Upper mids are elevated and present forward. Clarity and detail retrieval are very good.
Vocals are also forward and prominent.
Male and female have excellent clarity and presence while remaining natural and accurate.
Highs are crisp and well defined, but ultra highs roll off a bit early at the cost of air and energy.
There is no hint of sibilance or harshness.
Head Stage is clean, clear, and open.
Width is good, between the ears.
Height is also good, doesn’t extend overly high, but sub bass extends low.
Depth front to rear is also very good.
Layering and separation are very good on all three axis.
Imaging is excellent. Individual instrument placement is precise and accurate.

Blue Module
Sub bass is less boosted, still very much present, with less bleed throughout the head stage.
Decay is quicker and resonance fades sooner.
The sub bass veil is “lifted” from lower and upper bass, this range becomes tighter with more fullness.
The Toms in the open volley of
“Metallica - Now That We’re Dead” are quicker and punchier.
Lower mids remain recessed.
Mid range opens up more.
Upper mids become slightly more forward and prominent, clarity remains excellent, detail and micro detail retrieval is improved.
Vocals also gain some additional prominence while remaining very detailed, natural and accurate.
Highs are crisp, clear and highly detailed. Ultra highs have more energy and air.
Head stage benefits by becoming even more open and spacious.
Width remains between the ears.
Height reaches higher with the additional air in the highs.
Depth front to rear is also better.
Separation and layering benefit from the additional open spaciousness.
Imaging on all three axis is, I believe, the best of any iem I have experienced to date.

- Summary:
The head stage on the Grand Maestro has me addicted.
With vocal boost ON, and the Blue module in particular installed, the GM head stage is nothing short of incredible, IMO.
Left right stereo imaging is excellent, top to bottom layering and imaging is excellent, as is front to rear.
On tracks that are recorded with good imaging on all three axis, individual instruments, sound effects, and vocalists present from every conceivable position on stage.

The Grand Maestro is very much a musical IEM.
The sound signature can be manipulated to personal preferences via the various modules and switch position combinations available. But the resulting sound remains refined and high quality throughout.

They like power.
With any source I tried I found I was either using mid or high gain setting. And I still was pushing the volume to 50-75% to make the GM truly happy.

Speaking of volume:
The GM has a very clean and clear background. With high quality recorded sources it will tempt you to keep sneaking the volume up a notch or two.
They can get loud, without distortion or congestion.
But, my experience on occasion was that I was inadvertently listening at volumes that quickly fatigued my ears.
Please: Rock out responsibly

The comments here are unbiased and my own honest reflection on this IEM.
I own this IEM, so I am not beholding to anyone with respect to opinion or commentary.

I will not out right recommend any piece of gear, because I am fully aware of the diverse nature of sound preferences among those of us who enjoy audio.
However, based on my personal preference, and experience, with other flagship IEMs.
I do believe FatFreq has a winner on their hands with the Grand Maestro.
It is very much worthy of consideration if you are looking at TOTL ear gear at this price point.

- Other Stuff:
A bit about me and the music types used for evaluation below.
If you give a cats meow about that stuff.

** note: I try to be objective, but I am biased somewhat by my personal preference for sound signature. I lean toward a more balanced sound with perhaps a slight mids forward bias, good bass, good mids, good treble.
I am somewhat treble sensitive in the 8-9K range.

I do NOT consider myself a professional/career reviewer as I have no formal training as a sound engineer or musician.
I enjoy doing evaluations as part of my hobby.
* i.e. the thoughts presented here are strictly personal opinion based on my hearing, your mileage may vary.

** My hearing taps out at around 12.5 kHz, I can hear 12.5 but it’s more a background sound. I think it is fair to note this.
“Air” is typically a reference to treble that is present above 12.5 kHz, it is therefore beyond my hearing capability. When I reference “air” in a sound evaluation I’m referring to where I perceive the positioning of the upper treble ranges, ie. where they present themselves within the sound stage/head stage.

*** I have large ear canals, and typically the stock tips included with most IEM don’t fit well for me. I have a selection of third party ear tips that fit well in most cases so I default to these. I will identify my tips of choice, but unfortunately, seldom can I comment on the stock offerings.

- Music:
varied selection of tracks from my playlists played from SD card. FLAC 44 through 192 and DSD 2.8 (64) through 22.4 (512)
My mainstay are Blues, Rock, Jazz, Country, Classical.
I also streamed Apple lossless for electronic, R&B, Death Metal, etc. to get a well rounded experience of how well this IEM handles a variety of genres.

The Grand Maestro - A Pinnacle Level Tunable Endgame IEM
"There is tunable IEM's on the market aplenty - but don’t sound like this creation from Fat Frequency"

Shoutout to a Friend for the generous loan of this wonderful IEM, And I am thankful to have had the pleasure of being able to enjoy this grand creation.

INTRODUCTION:

FATfreq
Handcrafted in Singapore
Founded in 2016 by engineers Aaron and Ben, FATfreq began as a service provider for IEM repair and modifications. With technical experience in the circuitry, acoustics, and driver configurations of over 20 IEM brands, FATfreq quickly became the go-to place for IEM rescue and restoration works.

Now Singapore's leading IEM company, FATfreq creates world-class IEMs and innovative systems for every musician - all at an affordable price point. Every piece is carefully built and tuned by hand, adhering to rigorous quality checks for our Pro-audio industry.

From <https://www.fatfreq.com/about-us>


Now let's get into it: The Techy Stuff
GRAND MAESTRO $3599 USD for Universal or $3999 for Custom
FATfreq Flagship 2023
Tribrid Technology
Quad EST Drivers
4 Configurable Bass Tunings*
Pressure Relief Module
• Comes with Black NOAH Modual - You need to purchase the Blue NOAH moduals to get the 4 tunable Tunings.
From <https://www.fatfreq.com/grand-maestro>

More information can be found here and non-affiliated purchase link: https://shop.musicteck.com/collections/fatfreq/products/fatfreq-grand-maestro
Musicteck even offers Financing!

Subjective Part of my Audio Review -

I share my impressions as I hear them with my ears.
As all our ears are different shapes & size so what I hear as bright or bass heavy -you might hear as dull and Vise-Versa; just something to be mindful of.

What makes my ears happy as a sound signature is a slightly more aggressive L shape. I love my Bass Sub and Mid Bass slam, love it all actually; and in balanced quantity. With the Bass, I prefer a faster decay the faster the better so as to not bleed into the mids., I am treble sensitive and prefer a slightly darker warmer replay with good treble extension.

I prefer the fast speedy bass of the Beryllium Coated Driver of my Xenns Mangird UP with a Beryllium Coated Driver. Of course, there are exceptions in the market - as I also find the bass of the Bio Diaphragm used in the Yanyin Canon special - has some special sauce like an 8" subwoofer that feels like a 12" Has the slam and some serious sub-bass! And the super cool Copper Alloy Shell IKKO Obsidian OH10 does some magic to the bass.

My music Library is widely varied from; Metallica, Great White, Cowboy Junkies, Pink Floyd, Adelle, Melisa Ethridge, Fleetwood Mac, Five for Fighting, Mänskin, Poncho Sanchez, Jimmy Smith, Chopin, The Crystal Method just to name a few. When not listening to my test tracks the majority is Jazz or Alternative Rock especially Female Rock. Lorde, Halsey, Alanis Morrisette, Evanescence. All depends on my mood.

Sources: E1DA SG3, Shanling UP5, Geshelli JNOG J2 with AKM4493 chip. Truthear SHIO (Dual Cirrus Logic 43198 DAC Chips)
DAP/TRASPORT: From Lenovo Laptop with Tidal, Hiby R6iii ( ES9038Q2M ), Samsung S22 Ultra with DSD Files.
Amps: iFi ZEN-CAN and iFi ZEN-DAC2 , LoxjiP20 & XDUOO MT-604 tube hybrid amps and Topping A90D Amp 4.4 Pentagon Balanced Out - Unless stated
Tips Used for the Grand Maestro were the Whizzer Easytips SS20

SOME STANDOUT TRACK IMPRESSIONS:
Let's Begin: BLUE NOAH FILTER , VOCAL SWITCH OFF

#1 "Snowman" by SIA
- On this track I found vocals just a real standout not only is the vocals just amazing but the bass is so satisfying to compliment the singing it gives a real nice thump very analog sounding just wonderful

#2 "Lux AEterna" by Metalica
- The base fast and weighty though I wish it did have some more mid base hit it is still a very satisfying replay and would do well with this kind of library as well.

#3 "Nils Cline" by Phil Colins
- Just so immersive and addictive it's a very busy track that has many elements and the Grand Maestro separated all of them and gave each part equal love it was so well done.

#4 "The Cave" by Marcus Mumform
- So much energy and liveliness it made this track a real standout the male vocals were bang on very nice very

#5 "Come As You Are " by Nirvana
- Here I found the quad EST implementation added just a hint of top end and special sparkle when mid-bass kicks in it's very musical it's a great mix.

#6 "All My Friends Are Here" by Joe Satriani
- OK this track Joe describes it as a musician actually a guitarist trying to control a wild beast and I will say in this multilayer track that the Grand Maestro did perfect layering and stage the guitar the ascending a major just WOW electric guitar was very electric.

#7 "Shape Of My Heart" by Sting
- I put this track in here as well I had the same problem I did listening to any IEM like the PENON 10th anniversary where they're just so incredibly musical that you actually have a very hard time reviewing what you're listening to. Because you get completely lost in the music and it's just such a wonderful feeling and you have to chuckle a little bit because you have to keep going back and listening to the same song over and over again in order to write down your impressions it's pretty fun yet annoying at the same time.

#8 "Live & Let Die" by The Royal Philharmonic Orchestra
- All the sections and the pieces get the space they need to breathe from the strings to the drums all unquestionably bang on tonality wise very exciting and the Grand Maestro made it sound lively and a great sense of stage and presence with excellent macro and micro details.

#9 "Unfinished Sympathy" by Massive Attack
- Sweet drops , goes low Yet the Grand Maestro actually had me wishing for a little bit more sub base that's funny to actually hear from a company and a line of IEM that are known to be bass monsters. Yet this shows the incredibly masterful skill of the tuning where you can still get a lot of base and yet have all the vocal and the high frequency energies done in a way that makes it a very enjoyable

#10 "Ubiquitous Mr. Lovegrove (LIVE)" by Dead Can Dance
- One thing the Grand Maestro does so very, very well is the ability to give you a realistic sense of the venue you can tell if you're in a big place a little place a big concert a massive concert an outdoor concert or an intimate studio.

#14 "Jetlag Corporation (Remastered)" by Aes Dana
- Another standout track where the EST are done in such a fantastic way again you got the very musical bottom and notes and then a perfect coherence of all the drivers and you get these added Sparkle's on the top end that it's impossible for you not to put a huge grin on your face as you're listening to this track.

#15 "Vivaldi Double Cello Concerto Mvt#1" by Tina Guo
- The grand does very much reproduce cello the way cello was meant to be reproduced very realistic and it made my hair stand up on end that's how well done it gave me the sense of being right there listening to it live.

#16 "Chemical Mentalist" by The Crystal Method
- You want to listen to the Crystal Method, Daft Punk, Or Yellow anything EDM the Grand Maestro will eat up for breakfast and spit out some spine chilling slam and no hint of sibilance or harshness to be found you can go crazy loud with this I am just be careful please people.

OVERALL SOUND IMPRESSIONS:
OK let me first start off saying that prior to putting the Grand Maestro's in my ears this is the first exposure I have had to this brand. Previously I have heard and seen much talk about how the Fat Frequency IEM are not only Bass monsters but also have a quite a bit of balance where it doesn't wash out the vocals or the high frequencies quite a marvel if you're talking about a + 20 DB gain hyper control bass boost on the Maestro SE and only a +7DB pina gain, that's quite a impressive feat.

Now going into this review and getting the Grand Maestro from a friend on loan, I was thinking it was also going to be a bass monster but quite on the contrary in the end I found and was still wishing for more bass than the Grand Maestro could throw out.

I was actually…. I'd hate to say it but a bit disappointed

That is of course until I've spent more time with the Grand Maestro, where I kind of got a better understanding of where they were going with the tuning. The GM is mixture of a very vocal forward VOX and a warm balanced IEM as well as taking a shot at making a monitor like neutral sound signature for the series.

It's very hard to actually describe the entire journey between the swapping out of the modules for the air pressure that changes the bass and of course the rest of the frequencies moving up is also affected as we climb up the frequency scale.

Let's just start off with the BLACK NOAH module vocal switch OFF, here where it has the most amount of sub bass boost it's in its most V shaped form and probably the closest to the maestro SE that being said they are not the same I don't believe from the impressions I've got from the friend who owns this IEM and having had both at the same time. This was my second favorite overall preferred tuning I found the vocals a bit overpowered by the base and had me wishing for a little bit more clarity on that end.

Now BLACK NOAH module with the vocal boost ON I will first say that I don't particularly enjoy the boosted vocals with the switch on with this position. Which is funny because I do have a great preference for vocal forwardness like in the PENON FAN2 where I really enjoy how forward the vocals are in the mix.

I didn't quite enjoy so much it here though but I must say it is a really awesome implementation to what it can do and how it changes the overall entire presentation.
For some I know that they will be their preference but for me I preferred having the vocal switch off and for the sound impressions that I did those were all done with the vocal switch off and with the blue NOAH filter in place.

Next up is the BLUE NOAH filter with the vocal switch ON now with this one this one is the most monitor like neutral configuration at the Grand Maestro can do and it definitely was not my favorite at all as I prefer a more substantial bottom end And I found this one was a little too muted for my taste.

Now BLUE NOAH with vocal switch OFF in this configuration I found the Grand Maestro to be a warm organic lush slightly vocal recessed presentation.

This was definitely my favorite version of the Grand Maestro I just loved what it did to vocals it was very musical and it was very easy to get lost in the music with this kind of presentation I didn't really like the upper mid gain with the vocal switch and at first when I listened to this with it off I thought maybe it was a bit recessed and it probably is in the mix if you listen to a different IEM that is more neutral you can tell but it's just so smooth and totally correct that you forgive it any shortcomings and you just kick back and enjoy the music.
Now with this configuration.

I found that I heard more of a mix with the instrumental kick drums came in more into play had more note weight Just love the base again it's just so tastefully done it's not overpowering anything and you get the EST's adding the sparkle on the top end all the instrumental sounded great and I really enjoyed the stage as well though with the switch on the stage goes from fun listen to hyper craziness that might be a little bit mind blowing.

Finally I must say that I wish I was the owner of this IEM. Though I would probably have done it in a custom version, as it is truly wonderful. The Grand Maestro it's a standout in a sea of similarly tuned offerings.

The interesting part about kilobuck IEMS is that manufacturers are willing to take a little bit more of a risks to try something different and that doesn't always work in this case it certainly does and I can see why not only Fat Frequency has a huge following but a bright future as well.

lots of people say that there is a law of diminishing returns when it comes to gear that tries to reproduce music but in this case I think the Fat Frequency IEM really breaks the mold. I think this is one is a standout.

There are many more choices that are much more expensive than the Grand Maestro, but for what this does it is unique and stands on its own. The GM is worth every penny you will spend on it because you will just enjoy just listening to the music the way you want, tailored to your personal tastes.

Thank you for taking the time to read my review.
My Video review is here: TO BE DONE LATER

My QuBuz Playlist:
Listen to the playlist Test Tracks by tonedeafmonk.audioreviews@gmail.com on Qobuz https://open.qobuz.com/playlist/14733715

My SQUIG:
https://tonedeafmonk.squig.link/

My YouTube Chan:
https://www.youtube.com/@tonedeafmonk

My Discord:
https://discord.gg/hhyg5PKK5X

FATfreq
Handcrafted in Singapore
Founded in 2016 by engineers Aaron and Ben, FATfreq began as a service provider for IEM repair and modifications. With technical experience in the circuitry, acoustics, and driver configurations of over 20 IEM brands, FATfreq quickly became the go-to place for IEM rescue and restoration works.

Now Singapore's leading IEM company, FATfreq creates world-class IEMs and innovative systems for every musician - all at an affordable price point. Every piece is carefully built and tuned by hand, adhering to rigorous quality checks for our Pro-audio industry.

From <https://www.fatfreq.com/about-us>


Now let's get into it: The Techy Stuff
GRAND MAESTRO $3599 USD for Universal or $3999 for Custom
FATfreq Flagship 2023
Tribrid Technology
Quad EST Drivers
4 Configurable Bass Tunings*
Pressure Relief Module
• Comes with Black NOAH Modual - You need to purchase the Blue NOAH moduals to get the 4 tunable Tunings.
From <https://www.fatfreq.com/grand-maestro>

More information can be found here and non-affiliated purchase link: https://shop.musicteck.com/collections/fatfreq/products/fatfreq-grand-maestro
Musicteck even offers Financing!

Subjective Part of my Audio Review -

What I Liked:
-With the use of the NOAH modules you can completely change the tuning of the grand maestro whether you want more base less space more trouble more vocal it has the ability to do any of these tunings with a very easy swap out of the balanced air pressure modules.
-With all of the four possible tunings from the NOAH modules at any one time is the bass never overwhelming any of the rest of the frequencies it's quite spectacular
-The bass is so tastefully done it has texture it has warmth it has organic quality that is lush and musical
-The treble is also another standout of the Grand Maestro where it is ever present but never overwhelming harsh or sibilant
-Now the EST implementation is exemplary of what can be achieved and in this case it uses quad EST drivers you would think there would be an abundance of added sparkle and Twinkle's but in reality they're there just to give you the super upper high frequency special sauce that can only be found in top of the line tunings.
the stage well it's just perfect for me it's one of those kinds of presentations where you get a great depth you get a great sense of height you get left or right information when it feels it should give you that information otherwise it keeps you focused center stage it's brilliantly done.
-The vocals it is a chameleon where you at one point get either a little bit laid back warm presentation with the vocal switch off or with the vocal switch on it really gives you a sense of front and center of the stage and you're being spit on by the performers very forward with the switch on in this presentation and is easy to do even while the IEM are in your ears.
-Fat freak offers not just the universal but also custom IEM'S so if you do find fitment an issue you can always go to the custom route except what do you do with your very expensive purchase that you've already bought? It would be nice here if Fat Frequency would take your I M back for a small restocking fee and let you upgrade to the custom.

The Not So great Stuff
-The vocals again here you're either presented with the laid back warmer signature or the very forward signature there is kind of no happy medium with or without the switch on with the Grand Maestro in my listening impressions so at any one time you are getting a colored reproduction of the vocals not a true monitor like style if that is your preference you will not find that in the Grand Maestro.
-In order to get the four possible tunings at this present time you need to buy a second set of the Noah modules the blue sets which is available but at an added purchase cost of over 100 US dollars they should come included especially at the price you're buying as I am for.
-The vocal switch is positioned in such a way that you can easily select it to turn it on or off, but you also can easily hit the switch when you're inserting or removing. Not that that is too much of a big deal you can immediately notice a difference with one on or one off and it sounds like channel imbalance; but in fact you've just got one of the switches on and one switch off.
The IEMS themselves are probably the largest I've ever seen they are big bois and are definitely not going to fit everyone. The saving grace here is that the nozzles are quite long and also this is a detriment as well for Fitment for some. I had to really select a proper tip in order to get a proper fitment and be comfortable but at any one time I could only get about 2 hour listening sessions before it became too uncomfortable for me.

A future change and feedback to Fat Frequency would be to maybe find a different place for that switch maybe on the top where it wouldn't be as easy to hit it's also been observed for some people that that switch hits the inner part of your ear making it also a bit uncomfortable for some people.


I share my impressions as I hear them with my ears.
As all our ears are different shapes & size so what I hear as bright or bass heavy -you might hear as dull and Vise-Versa; just something to be mindful of.

What makes my ears happy as a sound signature is a slightly more aggressive L shape. I love my Bass Sub and Mid Bass slam, love it all actually; and in balanced quantity. With the Bass, I prefer a faster decay the faster the better so as to not bleed into the mids., I am treble sensitive and prefer a slightly darker warmer replay with good treble extension.

I prefer the fast speedy bass of the Beryllium Coated Driver of my Xenns Mangird UP with a Beryllium Coated Driver. Of course, there are exceptions in the market - as I also find the bass of the Bio Diaphragm used in the Yanyin Canon special - has some special sauce like an 8" subwoofer that feels like a 12" Has the slam and some serious sub-bass! And the super cool Copper Alloy Shell IKKO Obsidian OH10 does some magic to the bass.

My music Library is widely varied from; Metallica, Great White, Cowboy Junkies, Pink Floyd, Adelle, Melisa Ethridge, Fleetwood Mac, Five for Fighting, Mänskin, Poncho Sanchez, Jimmy Smith, Chopin, The Crystal Method just to name a few. When not listening to my test tracks the majority is Jazz or Alternative Rock especially Female Rock. Lorde, Halsey, Alanis Morrisette, Evanescence. All depends on my mood.

Sources: E1DA SG3, Shanling UP5, Geshelli JNOG J2 with AKM4493 chip. Truthear SHIO (Dual Cirrus Logic 43198 DAC Chips)
DAP/TRASPORT: From Lenovo Laptop with Tidal, Hiby R6iii ( ES9038Q2M ), Samsung S22 Ultra with DSD Files.
Amps: iFi ZEN-CAN and iFi ZEN-DAC2 , LoxjiP20 & XDUOO MT-604 tube hybrid amps and Topping A90D Amp 4.4 Pentagon Balanced Out - Unless stated
Tips Used for the Grand Maestro were the Whizzer Easytips SS20

SOME STANDOUT TRACK IMPRESSIONS:
Let's Begin: BLUE NOAH FILTER , VOCAL SWITCH OFF

#1 "Snowman" by SIA
- On this track I found vocals just a real standout not only is the vocals just amazing but the bass is so satisfying to compliment the singing it gives a real nice thump very analog sounding just wonderful

#2 "Lux AEterna" by Metalica
- The base fast and weighty though I wish it did have some more mid base hit it is still a very satisfying replay and would do well with this kind of library as well.

#3 "Nils Cline" by Phil Colins
- Just so immersive and addictive it's a very busy track that has many elements and the Grand Maestro separated all of them and gave each part equal love it was so well done.

#4 "The Cave" by Marcus Mumform
- So much energy and liveliness it made this track a real standout the male vocals were bang on very nice very

#5 "Come As You Are " by Nirvana
- Here I found the quad EST implementation added just a hint of top end and special sparkle when mid-bass kicks in it's very musical it's a great mix.

#6 "All My Friends Are Here" by Joe Satriani
- OK this track Joe describes it as a musician actually a guitarist trying to control a wild beast and I will say in this multilayer track that the Grand Maestro did perfect layering and stage the guitar the ascending a major just WOW electric guitar was very electric.

#7 "Shape Of My Heart" by Sting
- I put this track in here as well I had the same problem I did listening to any IEM like the PENON 10th anniversary where they're just so incredibly musical that you actually have a very hard time reviewing what you're listening to. Because you get completely lost in the music and it's just such a wonderful feeling and you have to chuckle a little bit because you have to keep going back and listening to the same song over and over again in order to write down your impressions it's pretty fun yet annoying at the same time.

#8 "Live & Let Die" by The Royal Philharmonic Orchestra
- All the sections and the pieces get the space they need to breathe from the strings to the drums all unquestionably bang on tonality wise very exciting and the Grand Maestro made it sound lively and a great sense of stage and presence with excellent macro and micro details.

#9 "Unfinished Sympathy" by Massive Attack
- Sweet drops , goes low Yet the Grand Maestro actually had me wishing for a little bit more sub base that's funny to actually hear from a company and a line of IEM that are known to be bass monsters. Yet this shows the incredibly masterful skill of the tuning where you can still get a lot of base and yet have all the vocal and the high frequency energies done in a way that makes it a very enjoyable

#10 "Ubiquitous Mr. Lovegrove (LIVE)" by Dead Can Dance
- One thing the Grand Maestro does so very, very well is the ability to give you a realistic sense of the venue you can tell if you're in a big place a little place a big concert a massive concert an outdoor concert or an intimate studio.

#14 "Jetlag Corporation (Remastered)" by Aes Dana
- Another standout track where the EST are done in such a fantastic way again you got the very musical bottom and notes and then a perfect coherence of all the drivers and you get these added Sparkle's on the top end that it's impossible for you not to put a huge grin on your face as you're listening to this track.

#15 "Vivaldi Double Cello Concerto Mvt#1" by Tina Guo
- The grand does very much reproduce cello the way cello was meant to be reproduced very realistic and it made my hair stand up on end that's how well done it gave me the sense of being right there listening to it live.

#16 "Chemical Mentalist" by The Crystal Method
- You want to listen to the Crystal Method, Daft Punk, Or Yellow anything EDM the Grand Maestro will eat up for breakfast and spit out some spine chilling slam and no hint of sibilance or harshness to be found you can go crazy loud with this I am just be careful please people.

OVERALL SOUND IMPRESSIONS:
OK let me first start off saying that prior to putting the Grand Maestro's in my ears this is the first exposure I have had to this brand. Previously I have heard and seen much talk about how the Fat Frequency IEM are not only Bass monsters but also have a quite a bit of balance where it doesn't wash out the vocals or the high frequencies quite a marvel if you're talking about a + 20 DB gain hyper control bass boost on the Maestro SE and only a +7DB pina gain, that's quite a impressive feat.

Now going into this review and getting the Grand Maestro from a friend on loan, I was thinking it was also going to be a bass monster but quite on the contrary in the end I found and was still wishing for more bass than the Grand Maestro could throw out.

I was actually…. I'd hate to say it but a bit disappointed

That is of course until I've spent more time with the Grand Maestro, where I kind of got a better understanding of where they were going with the tuning. The GM is mixture of a very vocal forward VOX and a warm balanced IEM as well as taking a shot at making a monitor like neutral sound signature for the series.

It's very hard to actually describe the entire journey between the swapping out of the modules for the air pressure that changes the bass and of course the rest of the frequencies moving up is also affected as we climb up the frequency scale.

Let's just start off with the BLACK NOAH module vocal switch OFF, here where it has the most amount of sub bass boost it's in its most V shaped form and probably the closest to the maestro SE that being said they are not the same I don't believe from the impressions I've got from the friend who owns this IEM and having had both at the same time. This was my second favorite overall preferred tuning I found the vocals a bit overpowered by the base and had me wishing for a little bit more clarity on that end.

Now BLACK NOAH module with the vocal boost ON I will first say that I don't particularly enjoy the boosted vocals with the switch on with this position. Which is funny because I do have a great preference for vocal forwardness like in the PENON FAN2 where I really enjoy how forward the vocals are in the mix.
I didn't quite enjoy so much it here though but I must say it is a really awesome implementation to what it can do and how it changes the overall entire presentation.
For some I know that they will be their preference but for me I preferred having the vocal switch off and for the sound impressions that I did those were all done with the vocal switch off and with the blue Noah filter in place.

Next up is the BLUE NOAH filter with the vocal switch ON now with this one this one is the most monitor like neutral configuration at the Grand Maestro can do and it definitely was not my favorite at all as I prefer a more substantial bottom end And I found this one was a little too muted for my taste.

Now BLUE NOAH with vocal switch OFF in this configuration I found the Grand Maestro to be a warm organic lush slightly vocal recessed presentation.
This was definitely my favorite version of the Grand Maestro I just loved what it did to vocals it was very musical and it was very easy to get lost in the music with this kind of presentation I didn't really like the upper mid gain with the vocal switch and at first when I listened to this with it off I thought maybe it was a bit recessed and it probably is in the mix if you listen to a different IEM that is more neutral you can tell but it's just so smooth and totally correct that you forgive it any shortcomings and you just kick back and enjoy the music.
Now with this configuration I found that I heard more of a mix with the instrumental kick drums came in more into play had more note weight Just love the base again it's just so tastefully done it's not overpowering anything and you get the EST's adding the sparkle on the top end all the instrumental sounded great and I really enjoyed the stage as well though with the switch on the stage goes from fun listen to hyper craziness that might be a little bit mind blowing.

Finally I must say that I wish I was the owner of this IEM. Though I would probably have done it in a custom version, as it is truly wonderful. The Grand Maestro it's a standout in a sea of similarly tuned offerings.

The interesting part about kilobuck IEMS is that manufacturers are willing to take a little bit more of a risks to try something different and that doesn't always work in this case it certainly does and I can see why not only Fat Frequency has a huge following but a bright future as well.

lots of people say that there is a law of diminishing returns when it comes to gear that tries to reproduce music but in this case I think the Fat Frequency IEM really breaks the mold. I think this is one I am that is a standout.
There are many more choices that are much more expensive than the Grand Maestro, but for what this does it is unique and stands on its own. The GM is worth every penny you will spend on it because you will just enjoy just listening to the music the way you want, tailored to your personal tastes.

Thank you for taking the time to read my review.
My Video review is here:

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Listen to the playlist Test Tracks by tonedeafmonk.audioreviews@gmail.com on Qobuz https://open.qobuz.com/playlist/14733715

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