How many of you have Fosi Audio Amp?

[CharlesJones166]

I'm not particularly knowledgeable about audio, but I'm in search of a Bluetooth sound solution that offers excellent quality. I'm curious to know what the general consensus is on these forums regarding the purchase and overall satisfaction with Fosi Audio amplifiers and Bluetooth products for everyday use. And fosi audio has new model of their TPA3255 Class D Amp, do you think it's a good choice?
https://www.fosiaudio.com/product/2-channel-amplifier/v3/

 

[-Jim-]

I got a Aiyama A07 instead of a Fosi Amp. (The new V3 is just starting to ship now.) But they are very similar as the use the same chip (TI TPA3255 ).

Here's another link where it was discussed.

I read both of these reviews some time ago (I'm a member there as well) and actually liked the AIYIMA numbers better than the Fosi, but the non-polarized plug put me off at the time. I have lots of PSUs that aren't polarized, and obviously both PSUs have CE & FCC certification, so there are fundamentally safe. So for me based on the data, it would probably come down to price and if I could get the higher voltage PSU with it to gain a bit more headroom.

Not that I need it, I would probably get one with a higher voltage PSU if I were you. The extra capacity is not a bad thing.

 

[-Jim-]

As of yesterday, the Fosi V3 is now available for sale. If you want it here's a promo code to save $12 (USD) => FAV3ASR12

The test results are pretty good with the 48 Volt PSU. I'd only go for this PSU and not the stock 32 Volt version as it hold back the power output too much.

The most annoying issue is the lack of a Post Filter Feedback (PFFB) circuit to compensate for the rise in high frequencies caused by load dependencies. Fosi advises they are going to "work on" PFFB so the next generation may resolve this issue.

This rise changes with the speaker connected to the V3. So different speakers will be affected differently and will have different curves. You may have to EQ this out (or change the position - toe in or out) if your speakers sound too bright for your taste.

Other than that it seems to be the top of the pile for these inexpensive Class D amplifiers at this time.

 

[PENG]

As of yesterday, the Fosi V3 is now available for sale. If you want it here's a promo code to save $12 (USD) => FAV3ASR12

The test results are pretty good with the 48 Volt PSU. I'd only go for this PSU and not the stock 32 Volt version as it hold back the power output too much.

The most annoying issue is the lack of a Post Filter Feedback (PFFB) circuit to compensate for the rise in high frequencies caused by load dependencies. Fosi advises they are going to "work on" PFFB so the next generation may resolve this issue.

This rise changes with the speaker connected to the V3. So different speakers will be affected differently and will have different curves. You may have to EQ this out (or change the position - toe in or out) if your speakers sound too bright for your taste.

Other than that it seems to be the top of the pile for these inexpensive Class D amplifiers at this time.

I don't think the rise from 3K will make the speaker bright sounding, because it only add +1.0 dB at 20K, and about 0.3 dB at 10K. Even a young kid with perfect hearing won't detect that little bit of "brightness" at such high frequencies, especially when listen to music instead of tones.

 

[-Jim-]

I don't think the rise from 3K will make the speaker bright sounding, because it only add +1.0 dB at 20K, and about 0.3 dB at 10K. Even a young kid with perfect hearing won't detect that little bit of "brightness" at such high frequencies, especially when listen to music instead of tones.

@PENG yes I do agree, but I thought it significant enough to at least mention as it could impact more depending on the speakers involved.

If I was going to buy one of these inexpensive amps to muck around with, this V3 looks like the one to buy at the moment.

 

[PENG]

@PENG yes I do agree, but I thought it significant enough to at least mention as it could impact more depending on the speakers involved.

If I was going to buy one of these inexpensive amps to muck around with, this V3 looks like the one to buy at the moment.

It is a good cautionary note, sort of..., relative to most class AB amps especially if the range is limited to 30 kHz instead of 200 kHz. Quite often though, people get mislead by the scale of the graph, such as in this case. If amir had used +5 dB per division on the Y-scale, the curve would look very flat from 20-20,000 Hz.

If I need an integrated amp now, I would for sure try out the V3. It beats so many amps in the ASR chart. Again people will say THD+N is just one metric, but then again, how often do we see amps that managed >80 dB SINAD that measured poorly on other metrics, hardly any!!

I have only one integrated amp, the US$500 (but I got it for less than that in CAD when Bay Bloor had it on sale) NAD C326BEE, that should measure similar to the C320BEE below, it costs at least 4X, yet since I only use one analog input, the Fosi amp would have been a better choice if it was available back then.

The NAD amp would likely last longer but for CAD 110, even if the Fosi amp lasts only 3 years, I wouldn't complain.

My only made in China amp is the Nobsound G2 Pro that uses the same TI chip. It is doing great powering my Energy subwoofer that had its plate amp failed twice. The much more expensive OEM replacement lasted for less than 3 years anyway and I hardly used it. Sometimes people just worry about the "made in China" thing too much, forgetting what they said about Toyota 50 years ago. Even if that's the worry, most, if not all of those cheap class D amps use the US, or German made chips anyway.

 

[lovinthehd]

No experience but could understand some circumstances where that V3 would be attractive, I just don't have one particularly. Maybe if it had multiple inputs to act more as a typical integrated amp. I'd have to get the 48V power supply for it, which would up the cost a bit....but that discount code could pay for part of it.....nice to see something offered like this in any case.

 

[PENG]

No experience but could understand some circumstances where that V3 would be attractive, I just don't have one particularly. Maybe if it had multiple inputs to act more as a typical integrated amp. I'd have to get the 48V power supply for it, which would up the cost a bit....but that discount code could pay for part of it.....nice to see something offered like this in any case.

I agree, and I believe we'll soon see something of a larger footprint that allows such amps to offer features somewhat closer to the below $1K integrated amps would offer. Price range would likely then jump to the $150-$200 range and that should still be very marketable, given their performance specs, verified by measurements. Such manufacturers are moving in the right direction by using the formula:

class D+chip power amp+brick power supply = low cost+performance+reasonable reliability+easy to repair.

Conventional integrated amps = large foot print+heavy weight+heat dissipation+harder and costlier to repair due to much more discrete components used+more negative impact on the environment

I think they know what to do and probably has some plans, but are in the market testing phase.

 

[-Jim-]

Gents, I'm just intrigued with the progress folks like Aiyima & Fosi have made in this realm.

I'd expect the next move will be some sort of a Post Filter Feedback (PFFB) circuit, and then an expansion into an integrated amplifier / DAC with various inputs; and maybe one with a Bluetooth function. Of course the big boys in the industry won't like them carving out this niche, so how the industry shifts may be most interesting of all.

 

[Kleinst]

I tried one recently. I was getting background noise/noise floor that I didn't get with the D

I agree, and I believe we'll soon see something of a larger footprint that allows such amps to offer features somewhat closer to the below $1K integrated amps would offer. Price range would likely then jump to the $150-$200 range and that should still be very marketable, given their performance specs, verified by measurements. Such manufacturers are moving in the right direction by using the formula:

class D+chip power amp+brick power supply = low cost+performance+reasonable reliability+easy to repair.

Conventional integrated amps = large foot print+heavy weight+heat dissipation+harder and costlier to repair due to much more discrete components used+more negative impact on the environment

I think they know what to do and probably has some plans, but are in the market testing phase.

I agree. I wondered why they wouldn't have a 5 channel version. that would be interesting. In my living room setup, I have to use a wireless SVS device to connect to my rear speaker. It goes into an AMP and into my rear speaker. I've been using the Dayton APA150 for this and it's worked pretty well. But I wanted to try the FOSI as its much smaller and would hide better in the living room where it is. The FOSI worked but there was a noise floor that was way to evident that the Dayton didn't have. So I returned it. I don't know if the wireless was driving that noise but it was much more evident with the FOSI than the Dayton.

Overall I'm sure with a little investment they could signficiantly undercut some of the other Class D AMPs and reset the marketplace a bit perhaps especially for ATMOS/Surround channels.

 

[MrBoat]

I have the Fosi BT30D Pro. It's ok and dead silent and has sub outs for both active and passive subs. I wish it was more robust with regard to headroom and that it was a true 100wpc into 8 Ohms. Otherwise, I treat these things like toys. I like more power and headroom, even for desktop use.

They have their place. A session with the Paul Carmody Speedsters and an 8" passive sub somewhat under the table. It's great for trying out other speakers without disturbing the main system.

 

[PENG]

I tried one recently. I was getting background noise/noise floor that I didn't get with the D


The FOSI worked but there was a noise floor that was way to evident that the Dayton didn't have. So I returned it.

If it is the Fosi V3, noise floor should be inaudible unless your room is extremely quiet, you are inches away, and you crank the volume up way too high. It has SNR better than many integrated amps with list price many times more expensive.

That's based on specs, and ASR's measurements:
V3 - Fosi Audio

SINAD	88dB
SNR	≥110dB
Dynamic Range	≥110dB
THD	<0.003%
Terminal Impedance	2~8Ω

Fosi Audio V3 Amplifier Review | Audio Science Review (ASR) Forum

Compared that to the $900 Parasound amp:
Parasound 2125 V.2 Amplifier Review | Audio Science Review (ASR) Forum
Fosi Audio V3 Amplifier Review | Audio Science Review (ASR) Forum

The V3 is a whopping 10 dB quieter at 5 W output, the gap would be larger at lower output, that is, most people's listening level (average spl output).

If you found the Fosi amp noisy, you probably should check other things, such as making sure it is not noise picked up from the interconnects due to the way they were run physically, or the quality of the cables etc.

There are many things the $900 amp can do that the $110 Fosi cannot do, but the example above does show the Fosi amp should be considered quiet, relative to many popular integrated amps in the below $1,000, even $2,000 range devices.

 

[PENG]

I should mention that I didn't want to pick on Parasound, and I do like their amps. The reason I picked that amp as example in my post was that I happened to trip over one post on ASR. It was just a coincident, and I am not saying that member's perceived improvement means anything other than it wis his own subjective perception.

Fosi Audio V3 Amplifier Review | Page 23 | Audio Science Review (ASR) Forum

 

[Kleinst]

It was this one
Amazon.com: [Upgraded Version]Fosi Audio TB10D 600W TPA3255 Power Amplifier Home Audio HiFi Stereo Class D Digital 2 Channel Integrated Mini Passive Speaker Amp : Electronics

Very possible also that something other than the AMP was driving the noise but I would point out I didn't get the same noises in the exact setup with the Dayton 150.

 

[PENG]

It was this one
Amazon.com: [Upgraded Version]Fosi Audio TB10D 600W TPA3255 Power Amplifier Home Audio HiFi Stereo Class D Digital 2 Channel Integrated Mini Passive Speaker Amp : Electronics

Very possible also that something other than the AMP was driving the noise but I would point out I didn't get the same noises in the exact setup with the Dayton 150.

The snr of that amp is 20 dB lower. That would be the reason. The Dayton 150's snr is only 10 dB lower than the V3's, fits right in between the guietest V3 and the noisist TB10D.

 

[Kleinst]

The snr of that amp is 20 dB lower. That would be the reason. The Dayton 150's snr is only 10 dB lower than the V3's, fits right in between the guietest V3 and the noisist TB10D.

Makes sense then! Thanks for checking. Again, I think there is room for someone to jump in on a multi channel AMP for a fraction of what they are sold for now. Will be interesting to watch. Wonder if the Class D pricing will ultimately slide although it's not clear if there is a large enough clientel to drive the prices down (like with processors vs AVRs for example)

 

[PENG]

Makes sense then! Thanks for checking. Again, I think there is room for someone to jump in on a multi channel AMP for a fraction of what they are sold for now. Will be interesting to watch. Wonder if the Class D pricing will ultimately slide although it's not clear if there is a large enough clientel to drive the prices down (like with processors vs AVRs for example)

It will, just take time for this to happen. I would have never guessed that I was so happy to let go over 100 lbs of class AB amps (my Bryston and Parasound Halo within one year and got myself 2 cheap, light, and small class D amps.

 

[rnatalli]

I have a Douk Audio amp with bluetooth which I use in the bedroom. It's very similar and in some cases exactly the same as the Nobsound and Fosi products. It works perfectly fine powering my in-ceiling Snell speakers.

 

[MrBoat]

I ordered the Fosi V3. I don't need it, but I have been dabbling in DIY chip amps and amp boards/modules anyway so these kind of fit in with those projects. I even have a pair of the TPA3255 chipsets around here somewhere that was for another project I haven't gotten to yet, or even remember what it was without looking.

I like assembling smaller desktop or portable systems to play with, instead of pursuing the otherwise fruitless game of upgrades with my main system. My main system is complete. It won't need anything until it either wears (not going to happen with what life I have left) out, or some act of God or chance kills it prematurely.

I have assorted and smallish budget pre/headphone amps laying around as well, and some Meanwell power supplies up to 48v too. Messing about with these relatively cheap systems tends to keep me from eyeing the higher end market so much, and tends to keep in perspective just how badass my main system actually is.