Okay.. here's the thing. Those outputs are not single ended. They are BTL (bridged) outputs so when you attach a single scope probe you are reading only one side of the bridge. If you attached a second probe to the negative speaker post, you would find the same audio signal, but out of phase. 1) The actual output voltage is double what the scope shows so .... Power = sqr(Voltage) / Impedance. ... V= 13 + 13 == 26 volts : p = (26 x 26) / 8 = 676 / 8 == 84 watts. or 168 watts on 4 ohms. 2) The PWM carrier you detected, will be on both sides of the bridge, but in phase, so that it produces no output. (this is pretty normal for Class D, btw) The other issues ... low gain, bad thermal solution, etc. are on point for Fosi products.

I purchased this amplifier for my future son in law. I ordered it without the stock power supply and bought a more powerful power supply for it. In a large room, it drives a pair of Monitor Audio Monitor 100 stand mounts and a repurposed Sony passive subwoofer from an old HT in a box system. Source is an entry level Audio Technica turntable and bluetooth. It sounds very good on both and gets very loud. I have recently added the Douk Audio T8 Pro 7 band equaliser which is also very good. I like this setup very much, and my future SiL loves it. One thing to bear in mind, if you're looking for max wattage, is that this amp splits the available power between the two TPA3255s, irrespective of whether or not you are using the passive speaker outputs (which makes sense). Accordingly, if your power supply is, say 240 watts, only 120 watts will be available for the stereo output. If you don't intend using the passive subwoofer outputs, you would be better off with a different TPA3255 amplifier, such as the Fosi Audio ZA3, V3 or BT20A Pro, Aiyima A07 Pro or Max etc.

Lovely review

Hi, Thanks a lot for your video but I'm sorry I'm not very familiar with some of the more technical terms. Was it 40watts per channel into 8ohm speakers? my speakers have a sensitivity of 87db. Will it be good enough for my small bedroom? Thanks in advance. I have my eyes on this mainly for the subwoofer out.

@Remonvik

3 ай бұрын

Hello. No, the 40 watts was on a 4 ohm load. Accordingly, 8 ohms will be even less

@Ron.Sarker

3 ай бұрын

@@Remonvik oh wow! that is a deal breaker! I'm currently using the fosi audio tb10d. I believe its about 75watts per channel with the 32v5a adapter. the bt30d pro will be a downgrade just for the sub out. too big of a gap. Thanks for your feedback. Hope your channel grows.

@Remonvik

3 ай бұрын

Thank you so much! I hope so too

I was looking to buy this just to power my sealed subwoofer i built using a ground zero 8" 4ohm driver that needs a 150w rms ideally, and a mininum of 100w rms, but this amp doesn't seem to be up for the task. Since i've got already an active pair of speaker, but i thought of going fully passive one day( and thus replacing them), i really had my mind set on this, but thankfully i just came across your video. At this point i might just go for a Luxus Audio SD200, control the main volume using an inline potentiometer, and feed the signal to my active speaker from the luxus's line out rca connectors. As you might have guessed, i have a 2.1 system that consists of an existing 2.0 active speakers with no sub output, and a home made subwoofer that i want to integrate with. If you can recommend me other options, either be it like the BT30D Pro, or plate amps with line out that can at least partially live up to their claimed wattage, i'd be very greatful! Thanks!

@Remonvik

3 ай бұрын

Hello. Do you need an amplifier with built-in power supply or just an amplifier board with lpf filter?

@donaldkillian9864

2 ай бұрын

I have two of these set in a 4.2 arrangement pushing two 15" horn speakers and two Klipsch f3 tower speakers a 12" sub and a 15" sub it's freaking awesome!!!!

@lupuradu

2 ай бұрын

@@donaldkillian9864 i ended up buying an AIYIMA A3001 just for the sub itself, we'll see along the road if i ever have to go passive for the speakers, i'll just get a dedicated stereo amp with sub pre-out to feed signal to the a3001. This a3001 amp came with a 36V 6A power adapter, and it's a mono amp based on a TPA3255D2, needles to say it looks good, stays cool, and manages to move my woofer properly. Couldn't be happier!

Can you turn off bluetooth in the BT30D pro? I want to use another BT device with LDAC via the rca port but the built in bluetooth stays active.

@Remonvik

2 ай бұрын

I think you can only do that by tampering with the board

@chinmeysway

Ай бұрын

unscrew the antenna ?

Seems unclear here though what the max SPL is at say 1 meter from source being a phone or laptop.. it’s to relative to say ‘it’s not that loud’ type a thing !

I have to 110-160 Watt speakers shoud i buy it or not ?

@Remonvik

2 ай бұрын

There is an opinion that the amplifier should be 20 per cent more powerful than the speakers. For better control. I'd recommend a higher-powered amplifier.

@thomasozanne5721

2 ай бұрын

​@@Remonvik If the amp is putting more than the speakers are meant to handle they just have a higher chance of blowing.

@Flimzes

2 ай бұрын

@@thomasozanne5721 Clipping is the main cause of blowing speakers, as during the clip the amplifier is sending a pure DC signal, meaning that 0% of the energy goes into movement, and 100% of the energy goes into heat in the driver - making it blow. Clipping happens when an amplifier is driven over its limits However, having too hot of a signal from an amplifier might make the speakers bottom out, creating a nasty sound, prompting you to turn down - no real damage done - no clipping, no overheating, no blowing.

Please don't buy it , excessive heat generated, even in stand by mode. No air circulation option. 😢

@notorious3875

15 күн бұрын

which one you recommend

@tenida_chatterjee

14 күн бұрын

@@notorious3875 any good amplifier with Good air ventilation/ circulation cabinet ...

@tenida_chatterjee

15 сағат бұрын

@@notorious3875 you can buy-- PYLE Amplifier