Fosi Audio TB10D amplifier review

[@jimhoward1655]

Had to listen to the outtake twice 😂. I miss seeing Snickers come up and get in the middle of everything.

[@59seank]

I miss Snickers too.

[@Ogma3bandcamp]

Good to see you are still trucking on, John.

[@klaushollinetz7494]

Another review on this amp, but now a clever and significant one. Thanks for that!

[@Douglas_Blake_579]

12:00 that is a switching transient, it is in phase on both arms of the BTL bridge and thus produces no output ... not sure why it's there but it is on all the TPA3255s I've tested.

[@jwl9286]

I'm so used to watching your videos that i am looking at the displays and looking taking a stab at the results before you describe them. Great video's! Thanks

[@migalito1955]

I am not surprised. The Audio Science channel tested the Fosi BT20A with the 48 power supply a while back and was surprised and pleased to see it fell in his assortment of test procedures in with and better than high quality thousand dollars plus amplifiers he had tested. It certainly was not as cool looking as the expensive amps with their meters and lights, but for $100 you just can not go astray.

[@antoniofrota637]

Ele da potência que vem declarando?

[@chinmeysway]

audio science channel… which one?

[@joelcarson4602]

These appear to be a pretty decent basic amplifier. I got one a while back, as I intend to re-cap a 1981 vintage Kenwood receiver and I need a temporary replacement. (Wish me luck) The TB10D will power a pair of Infinty 8 ohm bookshelfs to as loud as I reasonably listen to without getting warm. Sound decent as well.

[@jasonromich9919]

I have mine powering a pair of Klipsch tower speakers. No complaints.

[@ford1546]

A series-connected noise coil is not linear but changes with different ohm load. Correct me if I'm wrong

[@SERVISLAPTOPJOGJAPRO]

end of footage suprises me,... thought that something make some noise behind me LOL

[@ford1546]

An amplifier of 100w in 1% THD. should not be pressed more than to approx. 80w If you push this amplifier to the max, it gets hot and inside a tight box with no ventilation, the heatsink won't work as a heatsink after a while!

[@Budgethifiamps]

The AIYIMA A07 without this problem,Because he upgraded the heat sink inside

[@chinmeysway]

yeah that’s nuts this thing has no ventilation. bummer cuz it looks very good

[@pauljanda5262]

I have a pair of Fosi M03s for sub amps. They work great, even compared to big expensive AB amps! I'll keep the 845 SE tube amps on the mains, though.

[@antoniofrota637]

Da potência que vem declarando?

[@KausikKumaar]

best channel, cool wooden speakers and that mp3 player 😎

[@paulb4661]

Not sure about de-rating of the PS included, although I understand the specifics of the design. Old school principles suggest that either the amp cannot handle the full rail for too long, or they're saving a few quid on the brick ... or both.

[@paulb4661]

@Douglas Blake Haven't you suggested the chip gets too hot running at anything above 36VDC 4 days ago?

[@paulb4661]

@Douglas Blake In this case, as "in this example", the chip overheats, thus the amp cannot handle the full rail voltage due to little consideration given to thermal aspects. In this case, as "in this enclosure", same as above. Regardless, they are still saving a few quids on the brick - be it by design, or accounting, the result is the same. So it's both 🤣

[@paulb4661]

@Douglas Blake Because you have suggested that running it at 48VDC would cause the chip inside the amp to overheat, yet precisely that figure is marked as maximum allowable by the PS input jack. What dont you understand ?

[@paulb4661]

@Douglas Blake "either the amp cannot handle the full rail for too long, or they're saving a few quid on the brick ... or both" The amp cannot handle it, because they went for ready made enclosure design with not much consideration for heat dissipation, hence they are providing misleading info on the max rail voltage and providing a suitable, lower output voltage PS, which will not send the amp up in smoke, cheaper than the 48VDC would be and saving a few bucks in the process. Get it ?

[@Douglas_Blake_579]

@@paulb4661 Yes, and it does if you push it. (sorry about the delay here... some of my comments got erased, somehow)

[@aurthorthing7403]

I'd push it up to 42volts if'n it maxes out at 48volts. And I think I would mod the case by putting some speed holes or slits in the top...make it go faster.

[@jacklamata2544]

Hi, Can you please explain the connection on the oscilloscope? I want to test my amplifiers! And I have a FNRISI 2C23T oscilloscope. Can I test it with that oscilloscope? Or I need one with more power output? Thanks

[@KissAnalog]

Nice review John!

[@jerryking2418]

Great info. Much appreciated.

[@iikatinggangsengii2471]

memorable amp upgrade, always fun

[@MrAlexandreazevedo]

Comparing it to the TDA7498E board that you reviewed previously is it any substantial difference in sound quality?

[@pfagundes8340]

very nice.. thanks

[@scottbennett3119]

Great review! My 10d's volume nob has a little slack going from left to right. Did your review sample have slack or was it tight? Thank you.

[@JohnAudioTech]

I didn't notice this with my copy.

[@vinylmonster4907]

Apparently Fosi Audio are soon to release a new version of the FOSI AUDIO TB10d that will be compatible with a 48v power supply - unlike the one I recently bought and returned the BT30D Pro that wasn't and didn't take full advantage of the 3255 TI chip

[@manuelamadio1186]

Where did you read it? I know about the V3

[@vinylmonster4907]

@@manuelamadio1186 I was talking to a rep who responded to a complaint about the the BT30D Pro not being compatible with 48V 10amp power supply, who responded by telling me they'd like to send me the TB10d v3 as a replacement, however it still only arrived with the standard power supply. They did provide a link to their own 48v 5amp power supply, however that is for sale on their website for nearly 80 Australian dollars....

[@Douglas_Blake_579]

Actually the 32 volt supply is a very good compromise between heat and longevity. You are still getting a rather handsome 50w/ch from a $100 amplifier... so I don't see where that's a problem. You can purchase any 48v 10a power supply and run the amp but if you push it, you will get thermal shutdowns because of the fully enclosed case.

[@CatFoodDraino]

I wonder if one could upgrade the 4 blue filter caps for better sound?

[@laughlan22]

got a Infineon MA12070 amp recently, a douk audio one way better sound than the tpa 3xxx amps and i liked those

[@salilmahadik9396]

Really ? Are you serious??

[@ashishmalaviya]

What would happen if you did this same test with Pink Noise? Will the numbers reduce just because it has all frequencies?

[@jeffm2787]

If you push your trigger more positive or negative on your scope you won't need to worry about the flip back and forth comment.

[@JohnAudioTech]

Normally moving it near the peak works, but I get lazy.

[@780bpmclicktrack4]

wonder if this amp would power a set of DCM TimeFrame 600's? Theyre rated at 6 ohm

[@ford1546]

Isn't it a big problem that the coils sit the same way! Magnetic field and the sound will always go from one coil into the other if they sit in the same direction and close to each other. that's how a transformer works or a wireless phone charger works!. test this with an amplifier and speaker and 2 coils and you will hear how bad this is. Just remember to have a resistance of 4 ohms between the coil and the amplifier so that there is no short circuit on the amplifier.

[@PeterM-PeterM]

How did you remove the nobs? I am dying to re-allign mine and I am afraid i will break something.

[@JohnAudioTech]

If there is no set screw, then they just pull off.

[@klepp19]

Does bass and treble have a spot on the dial you know they are flat?

[@JohnAudioTech]

straight up 12 O'clock

[@prakasha7569]

Unfortunately there is no passive subwoofer amplification

[@chinmeysway]

babe it’s a 79 or less dollar amp

[@lasskinn474]

doesn't seem too bad.

[@CaribbeanGTR]

Were those output values per channel or total?

[@JohnAudioTech]

Per channel

[@bobwa399]

Can I use it with 60watt speaker with heavy magnet around its woofer, I mean my speakers are heavy. I was wondering if these new generation amps can play them like conventional old school of 90's or 80's.

[@chinmeysway]

probably yrs. old speakers can’t take very many ways actually. they’re more efficient tho

[@bobwa399]

@@chinmeysway why whats wrong with old speakers?

[@chinmeysway]

@@bobwa399 oh gosh sorry - bad typing. me, i think certain old school speakrrs are great! just picked up some snell speakers from i think 80's. just know if they are rated at 60 wpc then probably cant go louder than using 60 watts of power of the amp. but its better to have more on tap then to be underpowering the speakers. if they are more efficient say 90db then great, you wont need to turn the volume up as much / use the amps wattage as much. seems like a lot of older speakers post 70's are pretty efficient. not sure on the cheapo stuff though.

[@bobwa399]

@@chinmeysway can i use 6ohm speaker with tb 10d?

[@CaribbeanGTR]

Amazon has it listed as 600W. Where would that number have come from now we know the true RMS? "Fosi Audio TB10D 600W TPA3255 Power Amplifier Home Audio HiFi Stereo Class D Digital 2 Channel Integrated Mini Passive Speaker Amp"

[@birdyflying4240]

600 watt at 10% distorcion. In real life it's 2 x 180 watt with 48V 10A SMPS.

[@Douglas_Blake_579]

Fosi, like their competators, locked onto the "absolute maximum" rating of the chip. Do a search for "tpa3255 data sheet" and check the power vs distortion chart on the first page. There's your story ... 100w/ch on 8 ohms, 190w/ch on 4 ohms at low distortion. Beyond that the amplifier begins to clip and distortion rises vertically. With the "stock" 32 volt supply you'll get around 55w/ch on 8 ohms and 100 on 4. I understand why they would do that, but it is rather dishonest.

[@birdyflying4240]

@@Douglas_Blake_579 Even TI gives 300 watt 10% distrocion rating!

[@Douglas_Blake_579]

@@birdyflying4240 And that is where these guys got the 300 watt thing from. It will do 300 watts at 10% distortion for about 5 seconds before it goes into a thermal panic and shuts itself down. That is an "absolute maximum" rating, not what you can expect in normal use. The *low distortion* behaviour of the chip (what you want) is charted on the first page of the spec sheet... It's a very simple graph... it shows the chip reaching 100 watts on 8 ohms and 190 on 4... before the distortion starts rising vertically. It's right there on page 1, plain as day. What part of this is so hard to understand?

[@johnviera3884]

The big problem is that most HiFi speakers are 8 ohms and this amplifier is designed to give you the best performance at 4 ohms.

[@birdyflying4240]

I run a simular TPA3255 amp (Aiyima 07) and with 48v 10 amp SMPS supply they easy run my 8 ohm 3-way speakers and even my subwoofer. Just change the op amps for opa 2604 and you get high end for peanuts.

[@johnviera3884]

@@birdyflying4240 I upgraded to a 48 volt and don’t hear a difference. But try hooking up some 4 ohm speakers and you’ll definitely hear a difference. Unless you don’t care for more decibels, 8 ohms is fine.

[@kellynicklassen5896]

I use all of mine with a 36v 5amp supply. Aiyima a07, aoshida a7, upgraded fosi tb10d. Klipsch rp600mii, klipsch rb81ii and polk xt20. All are 8 ohm and can play extremely loud with clarity.

[@1pcfred]

Fosi it's an amplifier.

[@chellavee2248]

worst product i ever bought please don't wast your money on this

[@klepp19]

Why you say this? Mine will come from Amazon soon!

[@JohnAudioTech]

Exactly what problem did you have with it? Without explanation your message is worthless.

[@jmbuchela5424]

I totally disagree with you. I Let it run for 10 days straight and and paired with smsl DU1 dac, it sounds very good, regardless of price. Two things on that equation, I do not care for blue tooth, and I do not give a shoosh for MQA.

[@francohic]

@@jmbuchela5424 does it get hot when you touch it? Considering that you let it on for that long.

[@jmbuchela5424]

@@francohic I did not not notice anything unusual temperature wise, keep in mind I only had the volume at one third of the total output.