wondom bru5 pc dsp configurable TPA 3255 "300w x 2" mini amplifier

[orangezero]

I have had my eye on several different wondom/sure/partsexpress boards now for a while. I have an old 12in 140w sony subwoofer with failing electronics. I was thinking of using this bru5 to act as the amp while keeping the woofer and enclosure, then adjust the frequency cutoff in the software.

Is there any reason why you all think this would work really poorly? I believe at 8ohms this bru5 does 150w per channel. Will the chip be fine running long term with just one channel? I've considered getting another broken subwoofer for the other channel since my current receiver has two sub outputs.

BlinkTooFast, be sure to check out the sure audio website because they have all kinds of stuff that parts express doesn't sell. For example, https://store.sure-electronics.com/product/799 is a 10x50w that can do 7.3 audio out. There is also a 8x50w for little less. The only input is usb sound card built-in, but it would allow whatever pc you are using to have whatever audio software do whatever. As best I can tell the only way to get atmos or other digital processing is with some proprietary dolby software you get when you pay around $400 for a subscription to dolby something. Sorry, its been a while. I was trying to do a pc 9 channel dolby atmos system, but it didn't seem worth it at the time.

 

[seatac]

Could anyone tell me if this dru5 is mono configurable? I don't see any switches or options for it on the board.
I would like to buy two more and do a dual mono/dsp experiment with my acoustat 1+1's.
If it is, could you please post how to do it. I can solder small items, but don't know which ones.
My current bru5 has a disfunctional dsp plugin, so I would use it for my separate sub.
thank you

 

[seatac]

dual mono probably isn't what i need thinking about it now.
what i need is to have all the power from the amp go the either the left or right channel.
i asked if I could purchase them configured that way, but no reply yet.

 

[CedarX]

The TPA3255 is a 4-channels amp chip. In stereo mode (2-channels), it operates in "BTL" mode (Bridge-Tied Load, I believe that's how TI names it in the TPA3255 datasheet), so it's already in "bridge" mode.
The mono mode is called "PBTL" for Parallel Bridge-Tied Load. It requires some re-routing on the PCB itself, either using relays or, in a DIY-fashion, by cutting traces & adding jumper wires.
It does not appear that the BRU5 offer that option... but even if it did, it only increases the amp current capacity, so you only get more power when driving a low-impedance load --a 2 Ohm sub for example. PBTL is like putting two dual-mono amps in parallel, so if you use a 4 or 8 Ohm speaker/sub, you wouldn't get much additional power...

 

[seatac]

great and thank you. probably best is to just run one channel on each amp then. i bought 2 amps yesterday, so will just do that and also have dsp for each channel. thanks again.

 

[Zek]

probably best is to just run one channel on each amp then.

With some D-class amplifiers, it is not recommended that one channel be unloaded, as this output may burn out.

 

[Blink Too Fast]

I have had my eye on several different wondom/sure/partsexpress boards now for a while. I have an old 12in 140w sony subwoofer with failing electronics. I was thinking of using this bru5 to act as the amp while keeping the woofer and enclosure, then adjust the frequency cutoff in the software.

Is there any reason why you all think this would work really poorly? I believe at 8ohms this bru5 does 150w per channel. Will the chip be fine running long term with just one channel? I've considered getting another broken subwoofer for the other channel since my current receiver has two sub outputs.

BlinkTooFast, be sure to check out the sure audio website because they have all kinds of stuff that parts express doesn't sell. For example, https://store.sure-electronics.com/product/799 is a 10x50w that can do 7.3 audio out. There is also a 8x50w for little less. The only input is usb sound card built-in, but it would allow whatever pc you are using to have whatever audio software do whatever. As best I can tell the only way to get atmos or other digital processing is with some proprietary dolby software you get when you pay around $400 for a subscription to dolby something. Sorry, its been a while. I was trying to do a pc 9 channel dolby atmos system, but it didn't seem worth it at the time.

I cannot think of a good reason why running a stereo amp in mono would harm it. You would also get away with a smaller power supply.
Bear with me, and you'll see I'm also planning running empty channels...

A 10x50W amp would indeed be useful for a 5.1 setup where are the speakers are bi-ampable - but! - this 10x50W amp appears not to come with DSP, so would still need a 10x PEQ/DSP board.

My stereo hifi with obligatory tri-preamp requirements uses a MiniDSP Flex Eight as the DSP preamp, then a stack of Fosi V3 amps.

I'm considering what route to take for my 5.1 TV setup. The 5 passive speakers are currently mono-amped, and all capable of being bi-amped or tri-amped.
A MiniDSP Flex HT preamp (eight channel) could parse the 5.1 signals, and do full correction for the powered sub and to bi-amp the fronts with a pair of Fosi V3.
Daisy chaining the center (2-way) and surrounds (3-way) signals into four BRU5 would allow to split those signals for full multiple DSP preamping. One BRU5 vertically on the center, and three BRU5s horizontally on the surrounds.

a/ But that would be a cabling nightmare. Would prefer one 4-way DSP amp on each surround - hence Parts Express.
b/ I could reduce cabling by using two BRU5s on each surround.

Both these last two options, a/ & b/, leave an empty amp channel on each surround.

 

[seatac]

then i will add a dummy load to the empty channel. is there a recommended way to do this? I'm no expert, i just want it to work. My speakers are 4 ohm, so im assuming a 4 ohm resister of some type and size., thanx for the warning.

 

[seatac]

yes, the additional current is what im after with this acoustats, not the wattage. im told these dip to upper 2 ohm area in the higher frequencies so i just want to see if i can add a little more current there if the speakers want it.

 

[orangezero]

I just got a response from Wondom to a question about using the bru5 as a sub (doing the frequency cut via usb) and they said it wasn't a good idea. They suggested I purchase a newer product which seems more like a car audio sub amp that also is supposed to have the same dsp chip. Not out yet.

 

[orangezero]

A 10x50W amp would indeed be useful for a 5.1 setup where are the speakers are bi-ampable - but! - this 10x50W amp appears not to come with DSP, so would still need a 10x PEQ/DSP board.

Wouldn't the advantage of coming from a PC be that you could play music from software that has whatever graphic equalizer/dsp you required?

I'm also not sure how it would work with three channels for sub. 50w x 3 isn't probably wonderful going to three separate woofers, and I believe it was an amp chip that you couldn't just run in parallel to one woofer.

Wondom sure likes to make new stuff. I'd probably wish for a 10 channel usb input tpa3255 without having much experience with any of them.

The bru5 I notice is up to $55 on amazon, while aliexpress had it for $29 still.

 

[Joskanz]

I am pretty close to buying the BRU5 just wondering if there is the option to add high pass or low pass to this? I’ve only used a MiniDSP and haven’t played with ACPWorkbench.

 

[Blink Too Fast]

I am pretty close to buying the BRU5 just wondering if there is the option to add high pass or low pass to this? I’ve only used a MiniDSP and haven’t played with ACPWorkbench.

Yes, it has 2 banks of 10x PEQs, both apply to both channels, so you end up with 20x both-channel PEQs, not 10x stereo PEQs

These can be configured as hi/low pass, shelf, or peak filters, pretty much the same as my miniDSP Flex.

 

[Blink Too Fast]

Wouldn't the advantage of coming from a PC be that you could play music from software that has whatever graphic equalizer/dsp you required?

Yes, but neither my hifi nor my TV are a PC.

Be aware that a graphic equalizer is not the same as the PEQs that the BRU5, miniDSP, and the Dayton DSP amps have.

 

[Blink Too Fast]

With some D-class amplifiers, it is not recommended that one channel be unloaded, as this output may burn out.

I've been sleeping on this for a couple of days. I do believe someone made that recommendation, but it doesn't make sense.

At any time when playing music, amps are typically below 1% of their maximum load, and don't burn out.
Just because I have 6x300W amps connected to my speakers certainly does not mean I have a constant 1800W output. I doubt it ever goes beyond 5W, and most of the time when playing below 1W.

When music is not playing, both channels are unloaded, and do not burn out.
I leave my power amps on permanently, unloaded, and they do not burn out.

 

[juker]

I have been having bru5 for the past few days.

Just like few forum members pointed, I had problem with only 1 channel working. L&R being mixed up. Then it worked alright!!!!

I was driving a passive subwoofer. DSP software was very helpful. I am no expert on DSP but somehow managed to set the low pass filter and input gain and bru5 met its objective.

The biggest issue: it gets too hot quickly.

Perhaps its due to the 48v5a power supply of Aiyima.
Need to check this with something like 32v/24v supply.

Would be helpful if members can advise on this heat issue and how i could resolve it.

#wondom #bru5

 

[GGroch]

Hi juker, welcome.
What is happening as a result of it getting too hot? Is it shutting down? Or, does the case just get pretty toasty.

Shutting down would be certainly bad, and if you do not need the additional wattage a lower voltage power supply would run it cooler.

On the other hand the Bru5 is designed so that the case gets hotter than amps with purely internal heatsinks, so a toasty case may be normal.

The new Fosi V3 Mono utilizes heat dissipation similar to the Bru5, with the chip heatsink plate placed directly against the chassis bottom. Fosi got feedback from worried V3 Mono owners and just released a YouTube video showing how it works. So, depending on your symptoms it might be fine.

 

[juker]

Hi juker, welcome.
What is happening as a result of it getting too hot? Is it shutting down? Or, does the case just get pretty toasty.

Shutting down would be certainly bad, and if you do not need the additional wattage a lower voltage power supply would run it cooler.

On the other hand the Bru5 is designed so that the case gets hotter than amps with purely internal heatsinks, so a toasty case may be normal.

The new Fosi V3 Mono utilizes heat dissipation similar to the Bru5, with the chip heatsink plate placed directly against the chassis bottom. Fosi got feedback from worried V3 Mono owners and just released a YouTube video showing how it works. So, depending on your symptoms it might be fine.

Hi GGroch

Thank you very much for your time and the insights. (y)

The amp has not shut down so far. Perhaps, I did not run it continuously for long.
But the casing gets very toasty even when nothing is playing.

I checked the link. It was very helpful.
I do observe Fosi V3 also has ventilation at the sides. The Bru5 doesn't. As of now, it seems like an air fryer

Just wondering whether I should drill some holes on the sides of bru5 casing. Maybe in addition, find an external heat sink that could be attached to the bottom of the casing. Any thoughts whether this would help?

My use case: Wireless Sub
I connected a passive car sub to bru5 and hid the sub behind the sofa. The audio is in parallel to my HT amp from TV over Bluetooth.
The DSP is the USP and it helps me not break my head about RC/RL crossovers.
This setup did add to the overall lowbass. So the POC was a success.

Yet to do critical assessment about the group delay + room eq to have an effective wireless sub.
I do wish for a pre-out in bru5.

 

[GGroch]

RE: I do observe Fosi V3 also has ventilation at the sides. The Bru5 doesn't.

Just wondering whether I should drill some holes on the bru5 casing sides.

I think that the holes on the V3 are mostly for cosmetic/sales reasons. The scheme is to vent the heat out through the aluminum chassis...so it's getting hot means it is working and since the chip on both amps is on the underside of the circuit board venting the top side of the board through holes will probably not do much.

You can assure maximum heat dissapation by making sure the amp is not in an enclosed space.

You could also stick on taller feet (or put something under the feet) so that there is more air circulating under the amp.

You could turn the amp upside down so that the heat dissipates from the top rather than the bottom.

You could even glue an aluminum heatsink to the bottom of the chassis to increase the dissapation area and air flow.

BUT, Unless the amp shuts down my guess is that it is fine.

 

[juker]

Thank you once again.

I really liked these thoughts. (Y)

"
You could also stick on taller feet (or put something under the feet) so that there is more air circulating under the amp.
You could turn the amp upside down so that the heat dissipates from the top rather than the bottom.
You could even glue an aluminum heatsink to the bottom of the chassis to increase the dissapation area and air flow."

Now, I will try finding a suitable aluminum heat sink.