Fosi Audio V3 Amplifier Review

[antcollinet]

Hello. Please help. I have been using fosi v3 and aiyima a07 for a long time. I have wharfedale xarus 5000 speakers. Before that, I used less powerful ones. The problem is as follows. Firstly, aiyima burned out after long-term operation at high volume from a 48 volt 10 amp power supply and got very hot, after several attempts to force it to turn on due to overheating, the tpa3255 chip went to another world. Fosi behaves approximately the same way, but allows you to make it a little louder by a couple of decibels and also turns off. What should I do, how to feed the speakers? If I buy a pair of fosi mono, will they be able to pump up the speakers without turning off? (long-term loud listening). Moreover, the current amplifiers turn off earlier if you add even a little bass. I need a powerful amplifier that will provide long-term play at the maximum of the speakers. Sorry for the bad English, I am writing from a translator.

Hi - this is a review thread, and the mods like us to keep them just for discussing the review.

If you repost your question in the amplifier forum as a new topic, I'm sure someone will be able to give you good advice.

 

[T&T]

Which

Thanks for your further thoughts. There's a YT vid on this with music samples. The comments are illuminating, the general concensus is 5532 is good (rare Philips preferred), the OPA2604 is better, with a few outliers preferring (expensive) discretes. I believe Fosi bought the entire stock of OPA2604AP (DIP) & charges an arm & leg.
There's a discussion of fake 5532s but I believe I saw a post where Fosi showed a TI invoice for 5532s, that dispelled the myth. There are OPA2604AQ ceramic DIPs available on Ali but they could be fakes too.

Which would sound better opa2604aq or opa2604ap? The opa2604ap in ZA3 sound better than V7 vivid in my case

 

[Joe Smith]

Hello. Please help. I have been using fosi v3 and aiyima a07 for a long time. I have wharfedale xarus 5000 speakers. Before that, I used less powerful ones. The problem is as follows. Firstly, aiyima burned out after long-term operation at high volume from a 48 volt 10 amp power supply and got very hot, after several attempts to force it to turn on due to overheating, the tpa3255 chip went to another world. Fosi behaves approximately the same way, but allows you to make it a little louder by a couple of decibels and also turns off. What should I do, how to feed the speakers? If I buy a pair of fosi mono, will they be able to pump up the speakers without turning off? (long-term loud listening). Moreover, the current amplifiers turn off earlier if you add even a little bass. I need a powerful amplifier that will provide long-term play at the maximum of the speakers. Sorry for the bad English, I am writing from a translator.

Recommend you jump up to a Hypex-based amp rated for 250w at 8 ohms for around $550 (various makers offering finished amps) that is much better suited to long-play high output use cases... These smaller D amps are what they are, and while the Fosi monoblocks are a step in the right direction, they are still subject to issues I think when being used at the top of their power specs.

 

[wineaholic]

Just got it. The build quality is impressive. The miserable English in the advertisements still makes it look like a cheap product.

Is 24V 3A enough for Yamaha NX-E800 speakers?

Technical data:
System: 2-way bass reflex, compact speaker
Magnetic shielding
Chassis: 2
Tweeter: 2.5 cm dome tweeter
Woofer: 13 cm cone
Power handling (nominal/music wattage): 60 W / 110 W
Efficiency: 87 dB
Frequency response: 55-28,000 Hz
80 kHz (-30 dB)
Impedance: 6 Ohm

 

[NTK]

Just got it. The build quality is impressive. The miserable English in the advertisements still makes it look like a cheap product.

Is 24V 3A enough for Yamaha NX-E800 speakers?

With 24 VDC supply power, the amp can output <17 Vrms, which is 15 dB above the standard 2.83 Vrms used for speaker sensitivity rating. That means you speaker can output maximum 87 +15 = 102 dB SPL under the "standard" conditions (anechoic, 1 m distance, each speaker). Whether this is enough or not for you will depend on your desired listening level, listening distance, and room size. Below is the graph of max output power vs supply voltage from the TI TPA3255 amplifier chip datasheet (24 VDC supply highlighted). My guess is likely sufficient for listening at moderate volume.

 

[wineaholic]

Is 24V 3A enough for Yamaha NX-E800 speakers?

I have the 32V power supply now, but there is 0 headroom. Especially with quiet recordings. How much more Volume can I get with 48V?

 

[NTK]

I have the 32V power supply now, but there is 0 headroom. Especially with quiet recordings. How much more Volume can I get with 48V?

Does having "0 headroom" mean that you turned the volume knob to max and it is still not loud enough?

 

[wineaholic]

Does having "0 headroom" mean that you turned the volume knob to max and it is still not loud enough?

yes that happens. I am (when 5pm is the maximum) always in the setting range between 4pm and 5pm

There is another problem I only had one speaker connected. I changed the channel and it is much louder. So DAC, cable or amplifier defective.

 

[wineaholic]

The cable was the issue, weird.
Can this amp handle 2,0 Volt RMS from SMSL SU-1 DAC well? I'm not sure if I hear a bit distortion.

 

[NTK]

Can this amp handle 2,0 Volt RMS from SMSL SU-1 DAC well? I'm not sure if I hear a bit distortion.

I can't think of a reason why it can't.

If the amp behaves differently when you use a different channel, something is amiss. Have you tried connecting to both input channels of the amp, but test the output channels one at a time?

 

[KLi]

Hi there,
here are my 2ct: I use the Fosi V3 + P3 combo along with a Topping D 50 III and Wharfdale Linton 85th (look at the profile pic). For me this combination sounds sublime. It is more than loud enough, although I like to listen to low level jazz, and very good sounding. Not fatiguing in any way. Fills the room with nice sound Amp has the 32 V power supply. It barely gets warm. I love it and will keep it for the time being. I guess more amplification, as with mono blocs, would not be necessary and perhaps a waste of money.
Have a nice day

 

[Zek]

Wharfdale Linton 85th (look at the profile pic)

Are you really keeping those good speakers on the floor - that's unacceptable.

 

[KLi]

Are you really keeping those good speakers on the floor - that's unacceptable. View attachment 433307

Uhh, actually I don't. There are rubber mats underneath aka old mouse pads. ;-)

 

[Zek]

Uhh, actually I don't. There are rubber mats underneath aka old mouse pads. ;-)

You must be kidding.

 

[KLi]

You must be kidding.

Why? What is wrong with this cheap solution? I'm not allowed to scratch the floor. And I certainly not wanna scratch the speakers. And with the mousepads you can easily move and turn the speakers. The speaker stands are to big and ugly. Put some rubber underneath and voila. Done.

 

[DeepShadow]

Why? What is wrong with this cheap solution? I'm not allowed to scratch the floor. And I certainly not wanna scratch the speakers. And with the mousepads you can easily move and turn the speakers. The speaker stands are to big and ugly. Put some rubber underneath and voila. Done.

Not exactly... With bookshelf speakers, it's usually a good idea to have the tweeter at eye level for a more balanced sound and soundstage. Stands do exactly that, in addition to "killing" the vibrations that occur between the speakers and the ground. Using stands in this case is not just a fad, but a result of accepting the laws of physics. Nothing personal, but if you don't like the visual appeal of using stands, that's another matter. Best regards.

 

[mike70]

Why? What is wrong with this cheap solution? I'm not allowed to scratch the floor. And I certainly not wanna scratch the speakers. And with the mousepads you can easily move and turn the speakers. The speaker stands are to big and ugly. Put some rubber underneath and voila. Done.

Bookshelf speakers are designed to work with stands ... a basical rule is to position the tweeter at the ear level (more or less).

You're destroying the full sound capabilities of the speakers ... in favor of esthetics maybe? If that's the case you can buy 200 USD speakers, save money, achieve your esthetics goals and have the same results.

 

[antcollinet]

Не е точно така... При високоговорителите за рафтове обикновено е добра идея високоговорителят за високи честоти да е на нивото на очите на слушателя за по-балансиран звук и звукова картина. Стойките правят точно това, освен че "убиват" вибрациите, които възникват между високоговорителите и земята. Използването на стойки в този случай не е просто прищявка, а резултат от приемането на законите на физиката. Нищо лично, но ако не харесвате визуалната привлекателност на използването на стойки, това е друг въпрос. Много поздрави.

your translator isn't working.

 

[KLi]

Bookshelf speakers are designed to work with stands ... a basical rule is to position the tweeter at the ear level (more or less).

You're destroying the full sound capabilities of the speakers ... in favor of esthetics maybe? If that's the case you can buy 200 USD speakers, save money, achieve your esthetics goals and have the same results.

A bit off topic. But in all honesty I can't hear a difference between sitting on the ground and sitting in the lounge chair (which is still nearly ear-level - the Linton are big). Have no golden ears I guess lol.

I assume that the Fosi is more than good enough so that it is indeed my ears that cannot make out a difference. Regardless I am more than happy with the sound

 

[Zek]

Не е точно така...

Translated:
”Not exactly... With bookshelf speakers, it's usually a good idea to have the tweeter at eye level for a more balanced sound and soundstage. Stands do exactly that, in addition to "killing" the vibrations that occur between the speakers and the ground. Using stands in this case is not just a fad, but a result of accepting the laws of physics. Nothing personal, but if you don't like the visual appeal of using stands, that's another matter. Best regards.”