NEW BRZHifi PAD-30 : Dual TPA3255 +PFFB @ $99

[SampleSizeOne]

Now, if we had arranged for one to be sent to Amir... we'd know
There was the idea before if 10 people contributed 10 USD each he could purchase it..

I honestly hope he reviews the O-Noorus D4 Pro first. And that new Jade Audio amp O-)

 

[Ruediger]

I’ll go out on a limb here and say that the difference revealed by measurements will be completely inaudible when comparing the devices.

Why would we need to compare it to the A7 at all. Just because it shares the same TI amp chip?

Less than half the price. Just one input / no balanced input / no bypassing input buffer. No gain select. Case and cooling. Trigger vs. auto-sensing.

To me it's just a different approach in a lower price & feature class.

 

[Bleib]

Amir can't purchase everything people want tested especially with tariffs..
Easiest way is if someone in US buys it and sends it to him, but it can take months to receive it back because of a long queue

I honestly hope he reviews the O-Noorus D4 Pro first. And that new Jade Audio amp O-)

I've had two O-Noorus units and it wasn't a great experience. Loud sounds when changing settings and the 2nd unit had one dead channel. Well, at least I got a full refund after a couple of emails but...it's not a brand I want again.

 

[SampleSizeOne]

Amir can't purchase everything people want tested especially with tariffs..
Easiest way is if someone in US buys it and sends it to him, but it can take months to receive it back because of a long queue

I completely understand! The only reason why I would hope for a review soon (and why I mentioned this) is because the seller of the O-Noorus D4 Pro has mentioned early May that they will be shipping a unit to Amir.

I've had two O-Noorus units and it wasn't a great experience. Loud sounds when changing settings and the 2nd unit had one dead channel. Well, at least I got a full refund after a couple of emails but...it's not a brand I want again.

Hmm, that doesn't sound great. I can wait, but looking at all those interesting amps is really tempting all the time. I had my sights set om the WiiM amp Ultra, but I found out that users complain about latency. Since I also want to use it for gaming sometimes, 50~100ms of latency is too high. On top of that I made up my mind and I don't want an amp that relies on the use of a mobile app to tweak settings. Third is that I at least want it to have knobs for volume, bass and treble as a bare minimum (so no power amp with a separate equalizer/preamp). That's how I ended up looking at that new Jade Audio amp and the O-Noorus.

The Aiyima A80 looked interesting until I found out the LCD panel cannot be turned off

If you read between the lines, it may be clear: I'm looking for the holy grail here hahaha.

My budget is around 300~400 Euros, I would almost complain most power amps are 'too cheap'. My worry with those super cheap amps is that I suspect they do not offer good enough cooling. I don't mind paying extra for a good power amp that has decent heatsinking and a case that doesn't fry itself. But the newer FOSI amps I saw have an internal fan that apparently makes a distracting noise. If I can't find the holy grail, I'll just buy one that seems good enough and I'll mount a CPU passive heatsink to the case or something.

 

[john61ct]

If the 3e A7 feature set meets your needs, that is a very well proven choice, and within your budget, no?

All the devices in the testing queue here, we just need to wait.

But it is up to US to arrange to get this BRZHifi PAD-30 into Amir's queue, for example contacting the maker to persuade them (first asking @amirm if they want to accept it).

It is more than obnoxious to imagine they should pay ANYTHING out of their own pocket, given the ongoing huge value delivered to this community

 

[ICIETDIYEUR]

If the 3e A7 feature set meets your needs, that is a very well proven choice, and within your budget, no?

All the devices in the testing queue here, we just need to wait.

But it is up to US to arrange to get this BRZHifi PAD-30 into Amir's queue, for example contacting the maker to persuade them (first asking @amirm if they want to accept it).

It is more than obnoxious to imagine they should pay ANYTHING out of their own pocket, given the ongoing huge value delivered to this community

You are right.

However, it would be just as true to say that this site—so, and its members—would not exist if there were no manufacturers making equipment to test...

... it’s a bit like the chicken and the egg: which came first? Which one is more 'important'?

 

[Sam_138]

People hi

@ krisdeak :

Thank you for sharing your photos.

Could you let us know the values marked on the capacitors, as well as their diameter (in millimeters)?

View attachment 544303

Thank you in advance for your reply

Hi, I'm not @krisdeak, I hope you don't mind.
I disassembled the amplifier today, but not before removing the warranty sticker that was protecting one of the screws.

The information is as follows:

Rubycon 100V 100µF YXF Series.
Diameter 10 mm.

 

[TonyJZX]

good quality caps too

 

[ICIETDIYEUR]

Hello Sam_138, and thanks for your contribution.

Could you also provide the height of these capacitors (normally 20mm)—or at least the maximum height available to avoid touching the case (measured from the PCB surface to the underside of the top cover)?

TonyJZX confirms—as I mentioned earlier—that these are good capacitor models; however, referring to the Texas Instruments datasheets, the value chosen by the manufacturer is too low: 4 capacitors in parallel per TPA3255 (there are 8 on the PCB) give a total of 400µF.

The datasheets show that two 470µF capacitors are used for each TPA3255 (totaling 940µF) when the TPA3255 chips are operated in PBTL mode ->

Therefore, to operate according to Texas Instruments' specifications, it is necessary to replace the capacitors on the PCB.

There are other Rubycon capacitor models with better specifications that allow this result to be achieved; I have used the ZLH Series models as an example ->

You will notice that I have selected 63V models, which are more than sufficient for the PVDD voltage being used (the amplifier manufacturer recommends a maximum power supply voltage of 48V).

A 10mm diameter was chosen because it fits perfectly into the original PCB mounting locations.

The individual capacitance values will be either 270µF (4 x 270µF = 1080µF) with a height of 20mm—matching the originals—or 330µF (4 x 330µF = 1320µF), provided the 23mm height fits within the enclosure.

Replacing the capacitors in accordance with the datasheet recommendations will improve the amplifier's response to strong signal transients and reduce the load on the power supply.

I will return later to the subject of selecting a power supply for this amplifier, as the manufacturer's power chart can be misleading: it lists the power output for a single TPA3255 chip, whereas the amplifier actually contains two. To run it at full capacity, you therefore need a power supply capable of delivering double the current (in amperes) specified!

However, this requires careful consideration of how the amplifier will be used, taking into account both its heat dissipation capabilities and the level of distortion acceptable for hi-fi listening...
Note: The Rubycon ZLJ series also exists and would be suitable, but it is quite often out of stock.

 

[Ruediger]

Interesting!

Can you give me a hint about how much these 4 upgrade capacitors cost, roughly? The soldering is well within my DIY skills.

As a psu I would just use the standard 48v10a GaN brick that is also used by 3e, Aiyima, probabaly many others.

 

[ICIETDIYEUR]

Hello Ruediger

You can get these capacitors from Mouser or DigiKey, but shipping costs can be very high if you aren't in the US.

However, you can also get these same capacitors on AliExpress; given the unit price (which is higher than at Mouser or DigiKey), they are almost certainly genuine—judging by the reseller's margin—and besides, the cost and risks involved in counterfeiting these capacitors would be too high.

That is where I would get them.

As for the power supply, I ordered mine from Audiophonics (the 42V, 8.5A model).

This unit is distributed by Cisco—as can be seen in the photo of the back of the device—a specialist in professional IT equipment; consequently, its specifications and build quality inevitably meet very strict standards, and its reliability is beyond question for obvious reasons.

The power output I could achieve with this unit meets my criteria for future use:
- power output for 8-ohm impedance speakers (between 70W and 100W RMS per channel)
- maximum distortion level that I consider acceptable for a "High Fidelity" setup
- chassis temperature (and thus the temperature of internal components) when the amplifier is powered on but receiving no input signal ("idle"), given that the idle temperature is higher with these Class D amplifier circuits than when the amplifier is in use, even at full load.

 

[Ruediger]

My colleagues at work are always open to get some parts here and there across. They source electronic parts in bulk from asian spot markets. I'll give them the pic and request "proper, better 8 pieces of those".

 

[ICIETDIYEUR]

Regarding the RUBYCON ZLH 270µF - 63V capacitors, their diameter and height match the originals installed on the PCB exactly; their combined parallel capacitance yields 1080µF—slightly above the Texas Instruments datasheet recommendations (2 x 470µF = 940µF total)—making this a suitable value.

As for the 330µF capacitors, their suitability depends on whether they can physically fit inside the amplifier (given their 23mm height); the resulting total capacitance would be 1320µF, which is even better for the amplifier's operation.

Personally, I believe it is best to stay as close as possible to the values recommended by Texas Instruments, because the PFFB circuit used on this PCB can sometimes cause a "pop" sound when the device is turned off—an effect that intensifies with higher capacitance values in the PVDD power supply circuit.

To see why, one need only look at the total capacitance used in the Topping M300 amplifier (2200µF for both channels in BTL mode, or 1100µF per channel). As measured by Amirm in his review, this unit produces no "pop" sound upon either power-up or power-down—a testament to their recognized expertise in Class D technology and circuit integration.

As a reminder, with the BRZHIFI PAD-30, each channel in PBTL mode (using one chip per channel) would have a total capacitance of 1080µF if four 270µF capacitors were connected in parallel as I recommend—I'll let you guess why

 

[popej]

Therefore, to operate according to Texas Instruments' specifications, it is necessary to replace the capacitors on the PCB.

It is an application, not specification. Value of these caps depends on power supply constrution and obviously on design goals, like peak output power or inrush current.

 

[ICIETDIYEUR]

Hi popej

You are right in some cases; however, when looking at the circuit designs and component values that have proven their worth in measurements conducted by Amirm (Topping, 3eAudio, Fosi, etc.), one might question the choice of capacitor values visible on this PCB...
... even though the brand and model are perfectly respectable, I would lean towards the idea that the choice was dictated by economies of scale for this amplifier—especially considering its price point.

Admittedly, only comparative measurements could determine whether replacing these capacitors would actually provide an upgrade for this amplifier; nevertheless, based purely on theoretical concepts, I am confident in asserting that it would.

For my part, I’ve already ordered Rubycon ZLH 270µF/63V capacitors; it won’t cost much (It works out to €9.31 all-inclusive for me here in France), and making the 16 solder joints will take very little time.

I won’t even bother checking whether the result is effective, since the logic alone already points to that conclusion

Just a reminder: take a look at the supply voltages Texas Instruments uses for the measurements listed in their datasheets—after that, you can try to convince me that these are merely "specifications"...
... They are the ones who designed and built these power chips; I’d hardly presume to know enough to contradict them—would you?

 

[harkpabst]

I won’t even bother checking whether the result is effective, since the logic alone already points to that conclusion.

It would be way more useful if you did.

Changing components just because you know they are better is the Danny Richie style of doing it.

 

[ICIETDIYEUR]

Hi harkpabst

You are forgetting to mention (or consider) that the difference between him and me is that my 'solution' is inexpensive, I don't sell anything (and thus make no profit), and what I say here simply refers to proven, measurable solutions that any member can observe and understand—even without 'advanced' knowledge of electronics.

It’s just common sense; I’m not talking about 'snake oil' that costs more than the device itself—only to make it perform worse, as Amirm demonstrated in one of his reviews...

I am an enthusiast (with a bit of experience) who simply observes and shares his point of view on this site—everyone is free to do what they wish with it in the same way that members here 'vote' (sometimes with a certain subjectivity—it's only human) for the devices reviewed by Amirm.

 

[popej]

I’ve already ordered Rubycon ZLH 270µF/63V capacitors

Nearly 3x current value? I would check, if NTC for inrush current reduction is rated high enough.

 

[ICIETDIYEUR]

You might be right (something to check); in that case, I’d be forced to save about a dollar and the time it takes to make two solder joints—what an ordeal...

 

[harkpabst]

You are forgetting to mention (or consider) that the difference between him and me is that my 'solution' is inexpensive, I don't sell anything (and thus make no profit), ...

Point taken, that's a truckload of a difference, indeed.