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Douk HiFi 6N3 Vacuum Tube Preamp Review

Rate this product:

  • 1. Poor (headless panther)

    Votes: 114 66.7%
  • 2. Not terrible (postman panther)

    Votes: 41 24.0%
  • 3. Fine (happy panther)

    Votes: 11 6.4%
  • 4. Great (golfing panther)

    Votes: 5 2.9%

  • Total voters
    171

KaMiKaZeCATS

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I would be interested in seeing a comparison with tube amplifiers vs a SOTA AMP + dsp effect that adds this distortion. It seems easy to replicate. Plus you get all the benefits of a SOTA eg low noise, better crosstalk ect
 

ZolaIII

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In denial of 50+ years of progress to respect integrity of the input signal. Headless panther.
Well to the extent of 100+ years of audio signal processing (55 years of tubes, 30+ of transistors [still in use God bless] and 30+ years of digital [CD quality mass consumption at the beginning of 90's]) from source to ear I will have to change my vote to rolling chop. @amirm you naughty, naughty boy last one whose so horrible that it influenced my better judgement without paying more attention. This is rudimental and pore design even if SINAD is not horrid for such.
Controlled distortion is perfectly achievable with tubes. Following the design it should be a two stages; tetrode and petrode (buffers) with separate pin drain and dammn it can kick, look and act (including messure) far better.
 

dasdoing

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I am loving everything I am hearing on that video, regardless of it being made distorted or saturated, or not. The envelope is great.

I think the clean tube style (more odds than even!!!) in the video is what I would expect with a tube amp. the others change the balance or even "break" the sound.
personaly while I don't think the examples sound bad (well...the first one does for me) I always prefer the clean versions. it just souds more natural to me
 

Gorgonzola

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I’m no sure that harmonic distorsion is a harmonic experience :) the term is loaded with positive values .
When you get a THD it’s always overtones that bunch up higher in frequency? I’m not sure that will sound good on all music ? Especially when you stack this components up , add this to the tube DAC recently tested and even the distortion from the DAC will have distortion :D

I’m not sure about this 2nd harmonic sounds warm thing . It looks like a one size fits all solution it can’t really work properly ? For all music in all situations.

The safe bet re THD is as low as possible, do no harm to the signal. Then it won’t matter if it’s even or odd harmonies in a falling magnitude etc etc as they are not audible anyway . This would actually work for most people as at least the sound is as it is fro the source . If sounds meh write angry letters to the producers and then use tone controls or eq :)
I like your point about "stacking". I've asked tubophiles how may layers of tube equipment, (presumably generating 2nd order HD(, do you need -- tube phono and/or DAC; tube preamp, tube amplifier? Some say as many as possible :rolleyes:.

In my case I use only a tube preamp, (i.e. one tube layer); this pre happens to be one described as not very tube-like in sound. My up- + downstream components are both extremely low in SINAD, (Topping D90 and Purifi).

I'd agree, I think, that no all types of music benefits equally from tube effects; more importantly, not all recordings benefit equally. So for example large scale choral works tend to loose to detail or resolution with tubes in the repro chain, or at least that's my personal observation.
 

Gorgonzola

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Only 2nd harm at -55db may well be hard to hear at full power (when used as a pre-amp into a power amp).

As this is a pre-amp the output voltage, in normal listening conditions, will probably not go much beyond 0.5V (peak in music) where distortion will be even lower (guessing -70dB or so) but that hum may be its downfall.

Sometimes moving exposed tubes and open frame designs a bit away helps a bit.

It is an SMPS Douk describes it as:
With Hi-end switching power supply: Input: AC85-265V Output: DC12V / 2A
Indeed weird they did not go through the trouble of using a similar enclosure.

Chances are inside the amp there is an oscillator generating the HV which is then rectified by the tube just for the sake of having a tube rectifier (as some tube guys swear by it).

I wonder how they measured the following spec:
Distortion: <0.003%
As this would mean distortion would be -90 dB which, even ignoring the hum and noise, probably cannot be reached.
Then again, specs given by certain vendors can not be trusted anyway.
Thank you for these informed comments.

What I would like to understand, (as a non-technical person), is what are the alleged benefits of tube rectification. It seems to me that any component ought to run with an appropriate level of clean voltage. Is the anything special that tube rectification does in this regard?
 

F1308

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I think the clean tube style in the video is what I would expect with a tube amp. the others change the balance or even "break"the sound.
personaly while I don't think the examples sound bad (well...the first one does for me)I always prefer the clean versions. it just souds more natural to me
It is a matter of mood...
Every musician chooses this or that instrument for a given passage based on a felt need, and while the real thing is the real thing, a distorted one can be pretty nice, even inspiring.
Also, our brains are so capable there is no reason not to enjoy the new sound, removing anything annoying and turning it into fun, up to a point.
I was told adding the sixth note to the basic triad chord and getting acceptance from the people was a matter of decades.
 

dasdoing

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It is a matter of mood...
Every musician chooses this or that instrument for a given passage based on a felt need, and while the real thing is the real thing, a distorted one can be pretty nice, even inspiring.
Also, our brains are so capable there is no reason not to enjoy the new sound, removing anything annoying and turning it into fun, up to a point.
I was told adding the sixth note to the basic triad chord and getting acceptance from the people was a matter of decades.

I think there are 2 things that happen that can make added saturation sound better:
1) bad resonances get masked
2) it fills up the frequency spectrum when you have few instruments

now the horn section example shows a potential 3rd one, which is glueing instruments together. but I don't realy think this sounds good. I want to hear the instruments seperated. but I can get that the efect can be desired. it just makes everything more "synth-like"
 

Walter

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I don't think this is true. odds are more obvious so when wanting a clean sound they are more important to be avoided.
but odd harmonics can also be a goal for saturation. this video shows how diferent type of saturation efects the sound:

can't judge tube effects by how clean the second harmonic is
Many tube afficianados believe that the 2nd harmonic is the holy grail. This preamp seems to be well designed for them, whereas many actually have higher 3rd harmonics than second. That is the point I was making. Personally, I'd prefer as little as possible of either.
 

solderdude

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Is the anything special that tube rectification does in this regard?

It can supply less current, dissipates more heat (higher voltage drop, same current) so there really are no real advantages other than the reservoir caps being charged slowly (the tube needs to warm up) which would be one of the few upsides.
Subjectively some people claim amplifiers with rectifier tubes 'sound' better. This is not for a technical reason though.
In the early tube days there weren't high reverse voltage semiconductor diodes so this was basically the only way to rectify the AC.
 

Kennyknetter

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I can actually see a scenario where this could be fitting though.

I mean, the tube side, the "euphonic" side, of audio... they argue for the second harmonic of tube solutions to give the music a "glowing" aura to it. (I'm not sure whether the choice of that word is because of the actual difference that it makes to the music, or whether the glowing tubes just makes people 'feel like' the music is now warmer as well, though... anyways...) A lot of tube solutions have pretty strong third harmonics as well, though. Here, you basically only have second harmonics. And the thing is only 110 bucks. The way I see it, this pre amp could be a cheap way for people to find out whether they like their music "euphonic", or clean.

It's like:
-Try this one. Like it? No? Ok, now you have a piece of decoration instead.
-Like it? Well, godspeed to ya!
 

sarumbear

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Spkrdctr

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Wow, for Amir to ever call something "junk" is very, very rare. I would use the term more often but then I'm not a reviewer. Since he used my favorite word, I totally and completely agree with his findings. Junk. Seeing Amir used that word has really made my day! :)
 
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Gremlins

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Weird, when you read reviews on homecinema.fr in France, on douk audio P1, folks are raving about these preamps

Personaly, i would lile to try, but not ready to throw out 100 box on junk to try

For tube, i am looking at Elekit ..i think, it should be better as it is japanese
 

Helicopter

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I am actually pretty impressed with the profile of the distortion. I hear a lot of chatter about even harmonics, but most of the stuff measured doesn't really fit the hype there. The Pass Labs stuff is the only other thing I can think of that actually achieves a specific effect (though somewhat different). Too bad about the channel imbalance. If it weren't for that I might try one for a fun effect box. I might anyway for $110.
 

Bombadil

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Do we really need to test any more tube amps? Not being critical but it seems to be an endless rerun of a bad movie.
And perhaps not the best use of Amir's time.
 

solderdude

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I really don't want to be the person who may accidentally touch the male socket on the PSU that must have upwards of 200VAC on its pins. I'm not sure if that is even legal.

Its 12V out.
The high voltage is generated inside the amp.
 

SmackDaddies

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In the world of useless audio, this ain't bad. Power it up and put it on the shelf - just don't connect to anything.

I mean, I buy things for looks, hide the PS and just display the preamp.
 
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