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59% would recommend to a friend 
FX Audio TUBE-03MKII BT Tube Preamp & Headphone Amp
01 / 08
FX Audio TUBE-03MKII BT Tube Preamp & Headphone Amp
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Product Description
Between your audio player and your headphones, several pieces of equipment can improve your sound. If you’re looking for signature tube warmth, you can get them all in one device: the TUBE-03MKII from FX Audio Read More
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Customer Reviews
3.1
(37 reviews)
5star(9)
4star(6)
3star(10)
2star(4)
1star(8)
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keyboard_arrow_downPhanShei
26
Feb 8, 2021
checkVerified Buyer
Value for money but DROP's description is inaccurate
Supposedly sent 5654 tubes but received other tubes.
Supposedly include RCA cables but not included.
The product is fine, able to play with bass and treble with the switches. Its also great for a amateur like me to experience the tube rolling. I am fully satisfied.
They did offer refund so its fine for the customer service side. However, its not a great way to do business, making loss with such unnecessary mistake. They need to monitor closely on this aspect!
s4918
2
May 22, 2022
checkVerified Buyer
Great stuff
Initial review: The difference is significant whether you use it with a solid state or a tube amp. Yes there are only two inputs: one is the bluetooth input, the other is a standard RCA input, but the difference is remarkable with and without this little unit in the chain. I typically am not a proponent of bluetooth connection. I think that they cause too much loss to the signal. I like a simple but nice set up with good quality cables between the components. The ESS sabre DAC makes the bluetooth connection really that good for me not to miss the wired one. The sound is clear, transparent, and added to your amp of choice it has the potential to increase your soundstage considerably while keeping the sound very neutral and beautiful. I also like that it adds the bass and treble control to the mix. I have had it paired to a Kinter 2020A+ which provides some beautiful tube like sound (mellow, entirely not fatiguing yet neutral enough) and excellent power too. If you need more inputs, and would like to add a phonopreamp to the mix, I highly recommend to pair it, using high quality RCAs just the same as your connection to the amp, to a Technolink TEC-754 from https://www.phonopreamps.com/ . This was favourably reviewed as the "T-preamp" on TNT-audio. If you only want to add sources without a phono preamp and without (or with minimal) loss of signal/quality, choose the very simple Technolink TC-716. When I am not using the fantastic little Kinter, I hook the FX-audio to a Cayin CS55a. I could not recommend more the FX audio Tube-03 MKII. Also note that I am using it with the GE tubes you can get from Amazon, but I also like(d) and still like the standard 6K4 Chinese tubes. I think that they sound very neutral and beautiful too, in their own way. Purists beware, though, that from time to time (not too often!) the bluetooth pairing disconnects with a click, then typically comes back. Not all the time, just from time to time, but when this happens that can be annoying. Not sure what the cause is when that happens. I can live with this little quirk for the beautiful result otherwise.
Update after 6 months or so:
The FX Audio Tube-03MKII remains an essential component in my set up. Now that my Cayin CS55a has broken in (it took a few months but it is now where it should), and since I changed the preamp tubes in the Cayin to PSVane 12AX7 and 12AU7 -- taking the Cayin to a higher level of clarity and drastically also improving its headphone output, I continue to use the FX audio and am only satisfied with it in the chain. I currently use it as a welcome and necessary addition to a recently purchased ATOLL MS120 pre-amp, DAC and streamer, to warm up the sound of the ATOLL which, though a mighty and wonderful unit on its own, remains a digital product. I continue to use the FX Audio mostly as a preamp connected to the Cayin in the KT88 configuration. Also note that since my last review I upgraded the FX Audio by replacing all three op amps with Muse02. An investment that makes a world of difference both for the preamp stage and the headphone out of the FX Audio. I was however not taken by the headphone out on the FX audio, even with the new opamp configuration, until after I disconnected the RCA out from the amplifier. In this configuration (comprising the opamp upgrade) the Sennheiser 650 are now shining and I am not missing either the headphone out of the Cayin CS55a or my Cayin/Pier Audio PH5B (a stand alone headphone out with NOS 6J1 tubes selected by Pier Audio). Having discovered this tweak, I believe this shows a certain level of compromise in the design of this little FX audio wonder: the separation between the preamp and the headphone out is not perfect, but what should one expect from such a tiny little box that, in addition, does not come with a high price tag? With these updates, I would give the FX audio a 6 star rating if there was one. I urge all FX AUDIO owners to upgrade their op-amps. Oh and by the way: I have since my first review reverted to the Chinese 6k4 tubes which I now find I really prefer to the GE widely recommended on the net for the FX audio. I don't regret moving back to the 6K4S. they are that much more neutral and transparent. I use the tone controls to add a bit of bass (just a little) and I again find myself on a desert island surrounded , and transported, by my music.
Allow me to also reiterate my earlier advice: use these small inexpensive wonders as every component in your chain with the highest quality of cables you can lay your hands on. Triple shielded high definition copper recommended.
(Edited)
Recommends this product? Yes
Cyberthingy
289
Jan 17, 2021
checkVerified Buyer
Decent Preamp But Not as Described
For the low cost of entry I thought this might give my main audio rig a little warmth. I bought it in part because it was advertised as including GE tubes but that proved not to be the case. It came with Chinese tubes and lacked the pictured RCA cable. I did not feel like returning it since the cost was minimal so I ordered a pair of GE tubes from Amazon for $15. I did however, complain to Drop for the substituted tubes and they were kind enough to give me a credit to offset the expense of the new tubes. Well, it was a little tricky getting the tubes re-inserted because the fit was so tight and the pins were slightly out of alignment. I have used the preamp for maybe a few hours and it does add a smidge of color to the signal but not to the degree I had hoped. Maybe after more tube break-in I'll find it more pleasing. Only briefly tried the bluetooth feature to make sure it worked and it does. Range was actually pretty good. I'm not yet sure how well this will meet my needs but aside from the tube substitution it seems to perform well for a budget product.
Recommends this product? Yes
marcel54
15
Jun 3, 2021
checkVerified Buyer
Amazing
Thought it would end up to be a nice to have thing. Quite inexpensive. Bought separately same alternative tubes for just trying out. Instead it turn out te be a must have product and was worth the long time before and the following transit time. It brings a very different sound which each different tube and brought unexpected new life to my old Denon amplifier and Mission speakers.
Recommends this product? Yes
Tocotronic
38
Feb 3, 2021
checkVerified Buyer
Works, but has some design flaws
Globally, this little headphone amplifier works quite well. The good point is that it has a DAC and a Bluetooth connection integrated, so instead of connecting your headphones to your cellphone, you can rather hook them up to a more powerful source. The Tube-03MKII pairs very easily with your cellphone and re-pairs again without any further intervention every time the amp is turned on. It looks quite nice and spreads a nice reddish glow around it that looks cool especially at night (I have put it on my nightstand to listen to music at night). The output power is decent, it is sufficient to drive moderately demanding headphones.
The sound is ok, a nice, warm tube sound as it can be expected. The bass and treble adjusters are rather disturbing - I would have preferred not having them... Other than that, not so much to say sound-wise, ok without being top-notch, but I guess for price point rather good. The really negative point is the constant crackling noise that the amplifier transmits, and that is clearly audible when the music is in some more silent passages. I suppose this comes from the rather low quality of the Bluetooth interface - and unfortunately, there is no other input to the DAC than Bluetooth (like a USB connection for example), so if you want to use the DAC (and that is somehow the very reason or selling point of this headphone amp), Bluetooth it is, and crackling noise it is, too...
To summarize, for the price point a decent sounding tube amp with integrated DAC and Bluetooth connection - but only really enjoyable if you mainly listen to loud music.
Recommends this product? Yes
darkstormyrain
36
May 22, 2022
checkVerified Buyer
Noise noise and and wrong tubes.
This is a get what you pay for situation.
First thing after I put the tubes in (wrong tubes sent and pins bent) I do is plug in my Dunu SA6 IEMs and set up Bluetooth.
I swear I was listening to the snap crackle and pop of rice crispies cereal.
It is simple enough to use and nice for the bedside but that's about all I can say.
Oh no lag when playing beat star on my phone. That is a plus
Wrrqqarrr
4
Nov 6, 2021
checkVerified Buyer
Awesome first experience with tubes. Got some GEs from Amazon and the variation has been fun and educational. Also upgraded the Op-amps for more power, and now this lil guy has made my whole music collection sound brand new
Grimschank
6
Mar 9, 2022
WrrqqarrrHi, do you remember which opamp you swapped the stock one with? Cheers
Wrrqqarrr
4
Mar 10, 2022
GrimschankHowdy! I believe I used some MUSES03 from DigiKey. Was inspired by Audio Arkitekts to try this mod and swap the opamps of both my Tube03 (3 opamps) and the FX Audio DacX6Mk2 (2 opamps I believe?) for some great sound (https://youtu.be/3PXMWcIBVGA). Tubes are GE5654W (https://www.amazon.com/gp/product/B01BFJDTW0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)
matttnz
6
Jan 21, 2021
checkVerified Buyer
Broken, wrong Valves, awaiting new unit.
Dunno why mine posted twice but I see it’s for sale again and I got the replacement unit so here’s an edit re the replacement.
Same issue. Static/buzz when using BT and wrong valves.
Sent it back, drop staff excellent with this process, thank you to them.
(Edited)
Recommends this product? No
ClementN
18
Jan 17, 2021
checkVerified Buyer
Does not work
Received mine dead. Can't get it to work. The amp turns on without any problem but there is no sound coming from it, be it from the headphones jack or the RCA line output. No RCA cable as well.
EDIT : After contacting them, Drop's support told be they could not replace the product as the drop had ended and there was no additiona product in stock ; so they instead proceeded to a refund of the product.
(Edited)
Recommends this product? No
wrom_farmer
6
Sep 17, 2022
checkVerified Buyer
3 stars but really 2 stars if you like quality
First, let me tell you that this thing sounds pretty good and I'll be using it until it dies. <fingers crossed> I only use it for 2 things. The pre-amp to drive my AudioEngine A5+ speakers that are connected to my PC, or the headphone output. Even with cheaper headphones I can hear a difference. When I turn up the volume the music opens up, it doesn't just get louder. The sounds that were faint and distant are more apparent and clear.
The BAD:
What is wrong with it? Let's start with the red LED lights under each tube. They make it light up like a Charlie Brown Christmas tree. Between a black Sharpie and some black duct tape I was able to block out all that BS light.
The tubes I got in mine were some generic 3rd party tubes that have no identifiable information on them. I contacted customer support and they were not able to replace them as I wanted, but they made the situation right. Customer service friendliness and response time was a 10 out of 10.
***update***
After using this for about 2 months - It still works, most of the time. If I move it, touch it, or just give it a bad lok in general, I get loud static out the right channel and it starts cutting in and out.
I still love it. Cheap as hell but it still sounds dreamy. I doubt it makes it to 2023.
(Edited)
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