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FX-Audio Tube 02 Pro Review (Headphone Amp)

Rate this product:

  • 1. Poor (headless panther)

    Votes: 72 40.0%
  • 2. Not terrible (postman panther)

    Votes: 63 35.0%
  • 3. Fine (happy panther)

    Votes: 37 20.6%
  • 4. Great (golfing panther)

    Votes: 8 4.4%

  • Total voters
    180

solderdude

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I was talking generally, « normal« for a peace of gear may not be for all tube gear. In this particular case, This amp is out of it’s linear zone at 1 mW in 30ohms. Under normal listening conditions, it will certainly be in that increasing THD zone for all or most peaks. How much is audible I don’t know but based on Amir impressions, It’s fair to assume it is, in this case, too much even, but it doesn’t translate the same for everything with tubes out there.

At 32 ohm and 10mW peak distortion is -60dB = 0.1% distortion and in music is not really that audible.
With your average headphone this means 110dB peaks. Distortion from the headphone itself will be higher.
At 'normal listening levels' most people are around 1mW peaks.

Of course, driving low efficiency planars or 300 ohm headphones at impressive levels things will be different.
Just mentioning that those listening at sensible levels for music enjoyment with 'normal' headphones (the ones that will be buying things like this) will probably never reach levels with audible amounts of distortion.
 

DHT 845

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I am really tempted to buy this amp.... :)
What headphones would be best for it?
 

solderdude

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All sensitive (>105dB/V) and not expensive headphones.

No DC protection on its output (DC coupled) and internal -12V is made with DCDC converter so I would not recommend it with expensive headphones. Better than the old class-A Bravo thingies.
There are op-amps in the audio path, something 'tube purists' should take into consideration. As most audiophiles know opamps sound really bad ... :facepalm:
 
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DHT 845

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All sensitive (>105dB/V) and not expensive headphones.

No DC protection on its output (DC coupled) and internal -12V is made with DCDC converter so I would not recommend it with expensive headphones. Better than the old class-A Bravo thingies
Thanks, yes I though about inexpensive with high sensitivity...
 

Vict0r

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Thanks for the review!!

I voted "fine" because it's only $80, looks to be of decent quality, measures okay-ish for what it is and isn't trying to be anything ELSE than it is. It may not be for me, but that doesn't mean it's a "poor" product. You can do a whole lot worse with your money in that niche of the market.

Also, I quite like the no-nonsense design of the unit.
 
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Ajax

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I don't understand the point of a product such as this that knowingly (by adding distortion) changes the sound of what the musicians & studio engineers intended you to hear.

With the advent of digital we can now have inaudible levels of distortion so why not always aim for that and let the guitarist decide how much he wants to add to get "the sound" he is looking for.
 

solderdude

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Because people believe in 'tube magic' and subjective reviewers are always positive of anything ancient.
 
OP
amirm

amirm

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I don't understand the point of a product such as this that knowingly (by adding distortion) changes the sound of what the musicians & studio engineers intended you to hear.
I don't think the people who buy such things understand this aspect or want to believe it.
 

africanus

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I don't understand the point of a product such as this that knowingly (by adding distortion) changes the sound of what the musicians & studio engineers intended you to hear.

Because added distortion may be pleasant for some.

I was about to add 'I am not one of them' but then realised that I use EQ on my headphones and even add some slight reverberation so I am not using them as intended by the engineers who designed the headphones.
 

nagster

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I don't understand the point of a product such as this that knowingly (by adding distortion) changes the sound of what the musicians & studio engineers intended you to hear.
It's like forcing tomato ketchup on all foods. Even if it's Steak, Ice cream, Tiramisu, Sushi, Apple, Orange.
That's good if the person is happy, but I want to eat the food as it is.
 

ROOSKIE

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Except that according to Amir’s listening impression, it sounds like c**p. Sizzly, grungy… Don’t sound like fun to me.
Some people throw up on roller coasters and others literally run to get back in line to go again they had such a blast!
 
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ROOSKIE

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I don't understand the point of a product such as this that knowingly (by adding distortion) changes the sound of what the musicians & studio engineers intended you to hear.

With the advent of digital we can now have inaudible levels of distortion so why not always aim for that and let the guitarist decide how much he wants to add to get "the sound" he is looking for.
What, you mean destroy that perfectly compressed audio designed to sound good on a portable bluetooth speaker and TV speakers and that was lovingly mastered on a set of NS10's and approved by the artists the morning after an alcohol infused night that included 45minutes of sleep and playback on a set of B&W's?
Mostly kidding of course.
Just saying though that this whole as the artist intended thing is total BS a lot of the time.
Even with artists who are considerate of the recording process there are just so many variables.
 
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peng

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I can't disagree.
The good thing about this place is that most folks here will acknowledge that the ultimate purpose of all this... stuff... is to use it to listen to music. :)

Sometimes it may be a case of "listen to music" without audible distortions vs with distortions? Just kidding..
 

peng

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If there is a magic solution, we should be able to buy a preamp, power amp, integrated amp, or an add on device such as Nelson Pass's DIY harmonic generator by now. (https://www.firstwatt.com/pdf/art_h2.pdf)

How many popular brands actually advertised their preamp, integrated, power amps (among other hifi audio components) not designed for transparency/neutrality, but for the so called warm, music, and/or euphonic sound? The only one I could think of is Dan Agostino's, amps that would never buy. Funny how he changed his tune going from Krell to his own company.:D

I have yet to see any credible reviews on Nelson Pass's harmonic generator, that sounds like a fun little project. May be no one really know too much about this mystery and it may be a hit and miss kind of thing that someone actually heard the warm, musical, or euphonic sound from their chosen gear, while some just imagined he difference because they had been influenced by the marketing info and internet hearsay and that the imagined difference would disappear if they bother to do their comparisons in truly apples to apples tests.
 

peng

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Comon, in 2 of the 3 use case, it was characterised as "unlistenable" on the 3rd one, it was "OK at low volume" Who is it those peoples for who "if it's what you want"? Nobody wants that. I don't get the: "The amp simply does what audiophiles are asking: deliver them distortion and tons of it" Who are these people? I have been in the audio business my whole life and I have never met anybody asking for that. Even the most Biased. subjectivist tube enthusiasth there is.

Are you kidding, Nelson Pass (who I respect) don't design/build amps with intentional distortions but he, for one, did offer a generator that can offer you quite a bit of distortions. He wouldn't have offered it if no one was asking. "tons of it" could be just Amir tried to emphasize the point.
 

PeteL

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Are you kidding, Nelson Pass (who I respect) don't design/build amps with intentional distortions but he, for one, did offer a generator that can offer you quite a bit of distortions. He wouldn't have offered it if no one was asking. "tons of it" could be just Amir tried to emphasize the point.
How many did he sold? Have you met many audiophiles that purchase distortion generators? Me it's the first time I hear about that. Now sure, some people think that a bit of distortion may be a good thing, It can actually be interesting to try dial in some foe experimentation and yes, with parcimony some may even like that, but my point is, never to the point of making it sound like Amir Described. It's an amp, not an FX pedal. Is "unlistenable" also just to emphasize the point?
 

roog

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It seems that some people don't care whether the distortion is colouring (mutilating) their music, it might just be 'something that they like', although for the like of me I can't understand why.

What puzzles me more than this, is that these same people are just as likely to buy expensive 'boutique' cables made of fancy metal with pretty woven sheaths, cable supports, fancy fuses, custom HiFi furniture and 'power conditioners' in the supply, all in the name of improving the sound quality and of course the ubiquitous 'lowering of the noise floor' it just doesn't add up.
 
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