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.
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!
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!!!!
@@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!
You answered my question. From what I've read pre out is essentially untouched audio passthrough. I'm going to try connecting my active sub to passive sub connectors and hope for the best
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 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.
@@Ron.Sarker Don't be fooled ... your tb10d and this amplifier use the same amplifier chips. They will be far more alike than different ... especially giving you the same power outputs. In both cases ... With the 32 volt power supply you're going to get about 40 watts per channel on 8 ohms and 80 on 4. With a 36 volt that jumps to 75 and 140. On 48 you should get 100 and 200. Provided of course your power supply can deliver the needed current. You will be OK with 5 amps up to 36 volts but at 48 you really should have a 10 amp supply.
Remove the antenna and cover the connector with a bit of tinfoil (careful not to short it out). The BT receiver will then only pick up for about 6 inches allowing you to use your outboard adaptor.
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 !
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 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.
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.
Could you recommend a similar size amp that addresses those problem for similar cost?
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.
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!
Hello. Do you need an amplifier with built-in power supply or just an amplifier board with lpf filter?
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!!!!
@@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 I connect an active subwoofer to this pre out output?
yes... I did it for the same model and performing well
@@waynugopalbut the sub frequency and sub volume adjustment won't work right? Mine is getting ready to ship.
I hooked up my fosi to my active sub over pre out to LFE mode on my sub but it just control total volume not freq sub or vol sub...is that normal?
You answered my question. From what I've read pre out is essentially untouched audio passthrough.
I'm going to try connecting my active sub to passive sub connectors and hope for the best
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.
Hello. No, the 40 watts was on a 4 ohm load. Accordingly, 8 ohms will be even less
@@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.
Thank you so much! I hope so too
@@Ron.Sarker
Don't be fooled ... your tb10d and this amplifier use the same amplifier chips. They will be far more alike than different ... especially giving you the same power outputs.
In both cases ... With the 32 volt power supply you're going to get about 40 watts per channel on 8 ohms and 80 on 4. With a 36 volt that jumps to 75 and 140. On 48 you should get 100 and 200. Provided of course your power supply can deliver the needed current. You will be OK with 5 amps up to 36 volts but at 48 you really should have a 10 amp supply.
Sir,can this drive Sony xplode 1800w,320RMS sub-woofer?
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.
I think you can only do that by tampering with the board
unscrew the antenna ?
Remove the antenna and cover the connector with a bit of tinfoil (careful not to short it out). The BT receiver will then only pick up for about 6 inches allowing you to use your outboard adaptor.
Left Right channels are full range ?
Hi sir abhay Mumbai amplifier achcha response hai sir
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 !
Lovely review
I have to 110-160 Watt speakers shoud i buy it or not ?
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.
@@Remonvik If the amp is putting more than the speakers are meant to handle they just have a higher chance of blowing.
@@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.
As this little amp is less than your speakers recommended range and has no clipping indicators, I would suggest you look at something else.
❤️❤️❤️
Please don't buy it , excessive heat generated, even in stand by mode. No air circulation option. 😢
which one you recommend
@@notorious3875 any good amplifier with Good air ventilation/ circulation cabinet ...
@@notorious3875 you can buy-- PYLE Amplifier
@@notorious3875 Pyle Amplifier
if you don't bothered about warranty make some holes on sides of the case like mine