Douk A5 Budget Stereo Amplifier Review

[Blew]

This was the first thing I found - plastic mesh cut from an "organizer" type basket, the type you can find at some office supply or home organize/decorate stores. Cost just a few bucks. It'll do until I can find something else that looks better. I cut it to press-fit so it doesn't fall out, has to be pulled.

Tangentially related ... at the same store I found these $3 bamboo kitchen pots-n-pans "hot pads" (trivets)
I put some poly feet on them and use them under the Douk A5 and my tube preamp to aid airflow/cooling.
Plus I like the wood color makes a bit more visually interesting - esp combined with my SMSL DAC bamboo mod.

Interesting options, thanks. As the A5 chassis acts as a heatsink and can run quite hot, I worry about potentially melting/burning plastic and bamboo/wood materials. I assumed that metal would be the only safe choice. How warm does the A5 get with these on? Have you tested running it with them on for an extended period of time?

Come to think of it, I could use a thermal IR sensor to measure the external temperature of the A5 when the lid is both on and off.

 

[truth_soldier]

Interesting options, thanks. As the A5 chassis acts as a heatsink and can run quite hot, I worry about potentially melting/burning plastic and bamboo/wood materials. I assumed that metal would be the only safe choice. How warm does the A5 get with these on? Have you tested running it with them on for an extended period of time?

Come to think of it, I could use a thermal IR sensor to measure the external temperature of the A5 when the lid is both on and off.

I run all my devices on 24/7, never turn them off (DAC, A5, and tube preamp/buffer).
None of them ever get anywhere close to a temperature that can melt plastic or burn wood. All the cases are just warm to the touch.

You'd have to press the plastic directly onto the TPA3255 chip itself to maybe get it to melt, and the case is at least half the temperature of the chip.
The bamboo wood won't burn even if touching the chip directly let alone the case. It won't even change color as it's not touching the warm case and so is even cooler.

NOTE: I don't believe this stuff is even needed for cooling. I just like what the wood adds visually, and maybe (maybe) the improved airflow helps them run a little cooler and will make the gear last longer, esp since I never turn them off.

 

[truth_soldier]

As the A5 chassis acts as a heatsink and can run quite hot,

The chip gets to something like 150C degrees max. The chassis gets to only about 50C or to a max possible peak of maybe 65C degrees.
Many plastics melt around 150C and most woods burn at twice that or more.

oh, and another thing... the large bamboo square with the slots cut in it that I put the poly feet on, it's a kitchen pad made to set hot pots/pans on after removing from the stove. Those are probably hotter than the TPA3255 running at full power with no heat sink (max 150C).

 

[Lipaz]

I think I’ll buy 6 or 8 of these for a 4way OB and gove it a try. Currently it is 73USD without power supply. So disassembled and put in a rack with proper PSU(s) and pushing them with 48V and 10A, they’ll be good enough. 8ch amp with Sigma
Studio DSP for less then 600 USD. I know I know… the sound won’t be smoothy buttery creamy as audiophile community would describe, but I think it is good enough for me if I don’t here any hiss and it is transparent. I wanna here the audio content, not the amp.

 

[Blew]

The chip gets to something like 150C degrees max.

Yowsers, I wouldn't have thought it was *that* hot!

The chassis gets to only about 50C or to a max possible peak of maybe 65C degrees.

It feels like it's around 60-65C to me when the lid's on. With the lid off, or even just slightly open, it feels like it's around 40-50C. I definitely notice a difference between having the lid on and off/open.

I'll measure this when I can.

Many plastics melt around 150C and most woods burn at twice that or more.

oh, and another thing... the large bamboo square with the slots cut in it that I put the poly feet on, it's a kitchen pad made to set hot pots/pans on after removing from the stove. Those are probably hotter than the TPA3255 running at full power with no heat sink (max 150C).

Good point.

 

[SWSL]

1) Many people are not and will not be comfortable with cooling capabilities of A5. And knowing more information of how it behaves in regard of cooling is good to know for them before they spend their money and fortunately there is a bucket load of 3255 amps to choose from. Secondly, that finding is a remark for a company like Douk Audio who can improve in that field in the future, for better of all us who are consumer of their products.

...and you know this exactly how? This reminds me of a politician who prefaces an entirely unfounded assertion with "People are saying..."

Late to the discussion but just last week I needed to buy a good 3255 amp w BT,and aux out . Our Fosi BT-30D Pro has bitten the dust after 3 years. It was a great amp but ran really hot, even idled really hot. Other 5255 amps have not. It would cut out at parties so we ventilated it but still it was heat soaked all the time it was on. We are in the tropics.

I'm not thrilled about having to buy again so soon. I know, if prices are low, the argument goes, then we should be ready to buy frequently until they add up to be as expensive as a cooler running amp that can last. That is not my philosophy nor attitude towards paying for products that promptly go to the landfill. I see no reason why a device needs to fail sooner. I'll always pick the ones that have designs that can last a little longer, within a price range.

Contenders I had in sight were Fosi, Aiyima and Douk. I didn't see this thread but the Amazon reviews and comments below youtube videos made it clear that the Douk A5 (pro) runs hot, hotter than most 3255s. So I chose a different brand with less complaints about heat. Did it cost me more? No, less. I chose the Aiyima because the Fosi has a very old BT chip and I want the best BT I can get in this range.

So, being one myself, I agree that some people will not be comfortable with the Douk heat management. I don't want to keep buying amps repeatedly because the design is not careful of the heat. I hope that the companies do read comments like I do and adjust their designs to address the concerns that we voice online.

Cheers!

 

[truth_soldier]

but the Amazon reviews and comments below youtube videos made it clear that the Douk A5 (pro) runs hot, hotter than most 3255s....

...some people will not be comfortable with the Douk heat management.

what low-knowledge youtube commenters consider "hot" is pretty meaningless sans details.

The Fosi BT-30D Pro is a 2.1 amp that uses two TPA3255 chips so it's no surprise that it would run hotter than a single chip amp like the Douk A5 esp considering the case and heat-spreader is not considerably larger than the A5.
Additionally if you're driving a passive subwoofer with the BT-30D with some kind of crossover that second chip is likely driving a lot more power through the amp which will make it run hotter.

Also, the BT-30D Pro was redesigned. Was yours the old version with a bottom mounted heat spreader?... instead of internal top mounted large heat sink the new version has? It seems to me the earlier version with bottom mounted heat spreader was an inadequate design. If this lasted 3 years that's pretty good!

In any case this has no comparison to the Douk A5 which uses a single TPA3255 chip (it's not a 2.1 amp) and does NOT have a heat/cooling issue as far as I know. I run my A5 V2 with 32V 5A supply on 24/7. I never turn it off, and no heat problems.

 

[truth_soldier]

1) About Cooling
I combined and cooled the parts that connect 5V USB power using the leftover computer 120MM fan at home, and now my A5 is completely cool. ^^

2) New OP-amplifier Combination
I launched and installed the new Discrete Style opamp AK05 on Akliam and it looks great with the A5. The personality is close to Burson Opamp and I like it. It also looks great with the A5.

do you remember how much space/clearance there was between those four 10uF nichicon caps and the bottom of the AK05 opamps?
Did you have to use one or two DIP-8 risers?

 

[Originalaudiosceptic]

First post here but I wanted to document my experience with the Douk A5 Pro. I’m currently using an almost 50 year old Pioneer A-27 integrated that I had rebuilt by Amplifier Surgeries in Illinois roughly 10 years ago. It’s been a great amp but being so old I wanted to try something newer and thought I’d give one of these newer class D amps a try. After letting it warm up for a while I did a serious listen on a pair of Spendor 3/5 speakers through a new Schiit Mimir DAC and was very unimpressed. The dynamics were so suppressed and I had to check and recheck my cabling to make sure I didn’t screw up the simple connections. It was as if a blanket was thrown over my speakers. I returned the Douk and will try something different in the future.

 

[Jon L]

on a pair of Spendor 3/5 speakers

Those spendors measured at 81.7dB(B)/2.83V/m sensitive by Stereophile. Yeah, stick with large amps such as the Pioneer, which BTW operates first 30 watts in Class A then 120 watts.

 

[truth_soldier]

First post here but I wanted to document my experience with the Douk A5 Pro. I’m currently using an almost 50 year old Pioneer A-27 integrated that I had rebuilt by Amplifier Surgeries in Illinois roughly 10 years ago. It’s been a great amp but being so old I wanted to try something newer and thought I’d give one of these newer class D amps a try. After letting it warm up for a while I did a serious listen on a pair of Spendor 3/5 speakers through a new Schiit Mimir DAC and was very unimpressed. The dynamics were so suppressed and I had to check and recheck my cabling to make sure I didn’t screw up the simple connections. It was as if a blanket was thrown over my speakers. I returned the Douk and will try something different in the future.

for those hard to drive speakers it you're experimenting with the low cost class-d amps you should use a pair of mono-blocks such as the Fosi V3 mono's, or two Fosi ZA3's in mono mode, or two Aiyima A07 Max in mono mode.
That pioneer is a beast with like a 1000 watt power supply.
How much does that thing weigh?

 

[Audionaut]

I’m currently using an almost 50 year old Pioneer A-27 integrated that I had rebuilt by Amplifier Surgeries in Illinois roughly 10 years ago. It’s been a great amp but being so old I wanted to try something newer

Is it broken? Why do you want to replace the A27 of all things? It's one of the best integrated amplifiers ever built.

 

[Joe Smith]

for those hard to drive speakers it you're experimenting with the low cost class-d amps you should use a pair of mono-blocks such as the Fosi V3 mono's, or two Fosi ZA3's in mono mode, or two Aiyima A07 Max in mono mode.
That pioneer is a beast with like a 1000 watt power supply.
How much does that thing weigh?

Yeah, agreed. A cheap way to test would be to do the Aiyima A07 MAX as mono blocks with some 48v 10a power bricks. If you want a fair test relative to the Pioneer.

 

[Joe Smith]

Or, for more of a class d bang, a Buckeye 2-channel Hypex for around $550.

 

[truth_soldier]

Why do you want to replace the A27 of all things?

Maybe to save ~10X less annual electricity used?

 

[Audionaut]

Maybe to save ~10X less annual electricity used?

Perhaps, although I don't believe that hi-fi equipment plays a role in increasing global electricity consumption.
This forum and its users probably consume just as much energy as all hi-fi systems in the US and Europe combined.
New power plants are not being built for integrated amplifiers, but for AI.
A PC consumes about as much energy as the Pioneer A-27 integrated amplifier and runs much longer on average.
So yes, it's a possible reason – but for me it would be irrelevant, partly because I have installed a 12 kWp photovoltaic system with 10 kWh storage.

 

[Ropeburn]

Interesting options, thanks. As the A5 chassis acts as a heatsink and can run quite hot, I worry about potentially melting/burning plastic and bamboo/wood materials. I assumed that metal would be the only safe choice. How warm does the A5 get with these on? Have you tested running it with them on for an extended period of time?

Come to think of it, I could use a thermal IR sensor to measure the external temperature of the A5 when the lid is both on and off.

A hifi device that burns wooden or plastic furniture in intended use is defective by design and shouldn't be allowed to be sold in the first place.

That said, I highly doubt your concerns are warranted.

 

[Originalaudiosceptic]

Is it broken? Why do you want to replace the A27 of all things? It's one of the best integrated amplifiers ever built

I really just wanted to try some of the newer class D amps which some reviewers are claiming to be as good as class A/AB amplifiers. Plus the A-27 is pretty old and some of the parts are unobtainium so I wanted to have something available just in case.

 

[Joe Smith]

If you are thinking it might be a long term item, the you seriously should check out Buckeye’s product line. Worth a look anyway.