Douk Audio A100 TPA3255 300 watts x2 Digital Power Amplifier, Stereo/Mono Channel SUB Audio Amp for Home Speakers/Subwoofers/Bass Shakers

The media could not be loaded. I recently got the Douk Audio A100 amplifier, and it’s been fantastic. The power is impressive, and the sound quality is super clear. It really enhances my music and movie experience.The heat dissipation design is great too. Even after long hours of use, it doesn’t get hot, which is a big relief. It’s also very user-friendly with multiple modes to choose from, fitting different needs perfectly.I especially love the bass adjustment feature; it delivers a really powerful bass. The overall build quality is excellent, with high-quality components that feel durable.Overall, I’m extremely happy with this purchase and would highly recommend it to anyone!

To begin with, this is a very unusual looking amplifier - one that will either have folks loving the design, or hating it - there are no two ways about it. My feeling is that it looks and feels much nicer when you have it in front of you, rather than just looking at photos of it which do not do it justice. The design features lots of grooves and etchings, making you appreciate the A100 that much more once you have it in your hands.The entire casing is metal and the heat sinks being part of the casing itself, was an ingenious idea (at least for such an inexpensive class D model), keeping the amplifier lukewarm to mildly warm, no matter how long you have the amplifier on. The knobs are all metal - not plastic - and all of them click in detents, and the switches are very tactile - in other words, there is nothing cheap feeling about this amplifier at all. Now in my opinion, I think that Douk could have left the lines and silver design accents (other than the volume notches on the knobs) off the design - but that’s just my opinion.This A100 amplifier came as a surprise when all of a sudden I saw a quick review on it on You Tube (United States of Analog). I went to the Amazon US website and notice there was a 50% discount on the A100 off of it’s retail pricing of $199, so in essence, it was only $100. I’m no stranger to various Chi-Fi class D amplifiers, having very positively reviewed the likes of the Fosi BT-20A, V3, V3 Mono, ZA3, and the Aiyima A07, A07 Max, and A70 - in particular, with upgraded op amps in all of them. The one common denominator about all of them that really drew me in was the ability to change out the op amps (which I soon figured out could transform the sound).First let’s get right to the sound - and here is where 100's positives come into play. Even with the stock (you see them everywhere) NE5532 op amps, this A100 sounds very good - having an overall very linear sound, slightly warm audio personality. Its sound is full, very dynamic, with a warmish tonality. You could easily be mistaken to assume it could be an entry-level class AB amplifier if you were blindfolded. I’m catching myself using this description more and more as some of the Chinese Hi Fi companies are releasing amplifiers with superior components inside - along with allowing for op-amp changes.As I always do anymore, I leave my audio gear in the “on” position, as I found out a long time ago that components need time to break-in/warm-up to sound their best. So before I conducted any real listening sessions, I left my A100 on for at least 48 hours, and even then, the case never got above slightly warm (thank you Douk for those heat sinks).Now before I go on, please note that I’m discussing sound first - and then I'll discuss a few design/assembly glitches that can become frustrating (but do not affect the sound).LET’S TALK SOUND:BASS: Very dynamic and palpable - deep and tight and has a slight warmish tonality to it. Upper bass frequencies are warmer (than most class D amplifiers), and again…very dynamic. This amplifier is definitely not lacking in this arena. I just got finished listening to several classical pieces of music that showcase the low bass capabilities of fine audio gear. The first piece is Saint Saens Organ Symphony #3, featuring a large symphony orchestra and massive pipe organ with sustained notes down to 28 Hz. Listening to this piece through my KEF speakers and Presonus powered subwoofer, I had goose bumps because of the depth of the bass and realism that was projected. The next piece was Copland’s Fanfare for the Common Man in which the kettle drums and bass drums compete and once again, I was stunned (in a very good way).MIDRANGE AND TREBLE FREQUENCIES: Now here is where it gets interesting. You see, this A100 has a tendency to sound a bit more like an entry-level class AB amplifier because it has a slight warmish overall audio tonality. Brass comes through with that prerequisite bite, but is not harsh. Stringed instruments such as in a symphony orchestra, have that silky sheen to them and are easily showcased in the A100. Symbols have that required raspy sizzle, yet without any grating qualities. And things get even better when you upgrade the op amps (more about that later) - although you are limited in the types of op amps you can use here.SOUNDSTAGING, IMAGING, AND DEPTH: The sound staging is huge - forward and in front of your speakers. You feel like in the front rows of a performance. Imaging is fairy good (not as good as some amplifiers - meaning not necessarily as holographic), but you won’t be disappointed. Instruments are located in space with a decent amount of air around them, and the instrumental timbre of instruments sounded fairly realistic. Now I must say that depth is on average, good - however, not as good as let’s say the Fosi ZA3 with Sparkos Labs Op Amps installed. But you see, you can’t use the Sparkos Labs op amps inside the Douk A100 (more about that latter in the negatives section).OTHER AUDIOPHILE (INTANGIBLE) DESCRIPTORS: You can listen to this amplifier for hours without listening fatigue. The Op Amps I am currently using are two IC-based Burr-Brown OPA2604AP versions. I would have loved to use the much heralded Sparkos Labs SS3602 Discrete Op Amps, but unfortunately, they would not fit inside the A100 (please read some of my caveats about this A100 below). The A100 also has that “immediacy” feeling of being there. If it has just some more depth, then this amp would compete with some very expensive analog amplifiers. With excellent recordings and the right ancillary audio equipment, the combination can make you feel as if you’re at a performance.HOW DOES IT COMPARE WITH SOME OF THE COMPETITION?The A100 sounds very similar to the likes of the Fosi V3 and ZA3, with both Fosi models having a greater sense of depth, with a bit more “air” around the instrumentation (in particular, with the Sparkos Labs SS33602 op amps). I’d say that the Douk A100 compares most favorably with the Aiyima A07 Max and the A70 in overall sound tonality. The different Asian brands keep releasing these amps with the omnipresent TPA 3255 chip set (along with the stock, inexpensive NE5532 op amps), and you will notice at first, that there are very few differences in sound quality - other than in the bass arena. And bass is where the A100 shines! Now once you begin changing out op amps, you then will notice (some being remarkable) a change in the tonal personalities of different amps. That’s why I am very disappointed in the spacing of the Douk A100’s op amp sockets because they do not allow for the inclusion of the Sparkos Labs SS3602 discrete op amps, which have made very noticeable improvements to the sound qualities in “all” the amplifiers I used them in.NEGATIVE (SUBJECTIVE) ISSUES THAT ARE NOT SOUND-RELATED, BUT CAN TAKE AWAY FROM THE OVERALL INITIAL EXPERIENCE OF USING THIS AMP:CHANGING OUT THE OP AMPS: First of all, the A100 (like other competing amplifiers from Fosi and Aiyima) allows users to change out op-amps which can affect the overall tonality of the music. Kind of like tube rolling in tube amplifiers, changing out the op amps can result in noticeable changes to the overall tonality of the music. This was welcomed news when I saw this, but here is where the disappointment began.1. REMOVAL OF THE SCREWS ON THE CASE: I first had to remove the 9 screws to try and open the case (1 on each side, 5 on the rear panel, and 2 on the bottom). With my unit, somebody at the factory screwed on the screws so tightly that it took me a total of 30-40 minutes just to get into the case. Six of the screws I managed to get off using a standard hex tool (with lots of force used), but 3 of them were so firmly attached (and seemingly hastily screwed in at an angle) that the hex tool wound up stripping the screws. I had almost given up the effort to change out the op amps, but in the end, I wound up using a small bolt extractor bit on my drill, and even that took time. I finally got the 3 screens off, and let me tell you, I was cursing that entire time. I’m obviously short 3 screws now.2. THE OP AMP SOCKETS ARE TOO CLOSELY POSITIONED: Once you’re inside (the circuit board only slides partially out, exposing the op amps), you will disappointingly notice that the op amp sockets are spaced entirely too close. The only op amps you can use are the standard (small) IC-based versions - like the size of the stock NE5532’s that came with the Amplifier. I thought this was short sighted on Douk’s part since you are now confined to just a few op amps that are IC-based. I tried to insert the highly reviewed Sparkos Labs discrete SS3602 versions, but they wouldn’t fit. Discrete op amps tend to be larger (wider and longer), and tend to render the greatest audio improvements. I tried using the Sparkos Labs SS3602's in various configurations - for example, inserting one not having any risers in one slot, and then inserting the other one on top of two risers - but they still wouldn't fit. Then when I thought I had them properly seated, I put everything back together, only to get no sound at all, and I had to start of process all over again of taking all the screws out. Judging by the close spacing of the sockets, it appears that the only discrete op amps one might be able to use is the Burson V5i discrete op amps - but anything larger - well, forget about it. I was very disappointed and I had to settle on using the excellent Burr-Brown OPA2604AP op amps. The MUSES02 op amps work (and sound) very well also.LET’S TALK GAIN/VOLUME:I’m using the A100 in a standard desktop, near-field arrangement and I have a powered subwoofer under my desk. I have the low frequencies crossover set on my subwoofer, and the rest of the signal is being fed my KEF Q150 and Q350 bookshelf speakers. In the one review I saw of the A100, the reviewer mentioned that the overall gain/volume was very low. And I have to second that because here I am, just sitting 3-4’ from the speakers and I had to turn the main volume knob (the one all the way to the right) to the 2 - 3 o’clock position - are you kidding me? I can only wonder if you had this amp in a larger room with you sitting back some 9-10’, that you’d run out of volume.DOUK AUDIO RESPONDS (GOOD NEWS):After posting some of my A100 comments on various forums (and You Tube), Douk responded by first acknowledging the aforementioned issues. They informed me that they will be producing future batches of the A100 with the op amp sockets having greater spacing. They also said that they will revisit and adjust the volume issues that I mentioned. Now how long this will take to get those new batches out on to the market, remains to be seen. But it's nice to see Douk responding so quickly. Of course, for those of us who already have the "earlier" versions, this will only be good news for those folks who will wind up with the new versions. We're stuck with ours.RECOMMENDATIOS FOR THE FUTURE:1, Douk should also add balanced inputs for future models. Based on the specs, it is apparent that Douk (which is the same company as Nobsound) is trying to compete with the offerings from Fosi and Aiyima (I.E. Fosi ZA3, V3 Monoblocks, and the Aiyima A70). You should have included balanced input terminals also - that could have been a game changer, so it will be interesting to see what Douk will do with subsequent releases.2. Allow for firmware updates. Since this is a chip based amplifier, include a USB terminal and the ability for the users to download and update firmware (make it simple though). So many items now-a-days have firmware updatable components such as some audio gear, cameras, modern appliances, computers, etc. It’s time that some of these Chi-Fi components have that same capability. What it will do is to extend the product life of a particular component, upgrading and improving some performance and sound variables as time goes on, and thus negating the manufacturer having to release new gear in what seems like every other month. Just a thought.3. One of the key selling features that Chi-Fi companies have been touting, is the ability to change out op amps. But why then can’t these same brands design cases that makes changing op amps a breeze. Why do we, as users, have to jump through hoops as we try to access those op amps. There is one company that produces amps where with the release of just a few screws, the top half of the case lifts off - a very simple process - thus exposing the circuit board. Yet, other companies will make cases that almost dissuade the user from not even trying to change out op amps - sigh…MY RATING: So in the end, as much as this A100 sounds gorgeous (at least to my audiophile ears), the listing of the negatives I provided, cause me to give it just 4 out of 5 stars.Your mileage may vary…

Well, I was really looking forward to this amp. At first impressions, using it, it's a bit quiet.It comes well packaged and presented. The amp and power supply feel of high quality and have a good heft to them. Controls feel nice.The volume comes on slowly at first so you can dial in a quiet volume if needed, great. But after 25% volume it does nothing until you get to 60%. Then it comes up more rapidly to full volume. I don't know if they just have the encoder programmed incorrectly trying to create a tapered curve. Then the volume at full was disappointing, definitely not 100W. My speakers are 88db/1W/1M, I measured 92db at 1M at full volume. So 2-3 Watts?The sound is great, smooth and very musical, no problem there, even across 3 different speakers and vastly different types, it made each sound great. I like the ability to have the AUX out, with it's own volume for volume matching to another amp, great idea.I then ran the amp in SUB mode. Trying the controls I got very confused compared to what I was turning and the sound difference it made.The SW-FREQ knob seamed to raise and lower the overall volume of the base output.The Super-Base knob changed the frequency by lowering the cutoff frequency as you turn the knob towards +?I then wired the unit for MONO, using the two outer speaker connections on the back, this usually bridges the amp for double output in to one speaker. I found no volume increase in doing so, also confusing. I think they just keep both R and L amps happy by having a load attached, but give you the same output quantity.At this price point this amp should have:1). 3-4 times the output power.2). A remote control3). Have Bluetooth capability.4). Use conventional nomenclature on the knobs so you know what the function is.5.) Bridge the amp for MONO.For all the effort they put into the quality of the makings of this amp, they should have organized a focus group of Hi-Fi 'rs to make a few changes and had a winner out of the gate.

This little integrated amplifier is very versatile and useful for so many things.Despite only having a single analog input there are still so many ways of using this. I can easily see using it as a small desktop amplifier to drive 2 bookshelf speakers and a subwoofer. It would be great to run sound from a streaming device like a Sonos Port to some outdoor speakers. It would be great to drive a non-powered subwoofer. There's just so much you can do with it.In my case I have a workbench in my garage and will drive some floorstanding speakers that have been stored there. I'll enjoy having some music when working on projects in the garage.The amp sounds very good, Douk put some real effort into making this both good sounding and versatile. It's pretty hard to beat at the price they're asking for it.