Fosi Audio V3 Mono Amplifier Review

[Bleib]

I've heard lots of weird audiophile words for describing audio, but "nasally glass like" really takes the price. What does that even mean?

I bet even his wife heard if from the kitchen

 

[burkm]

Right - but that wont change the surface temperature of the device. It will only impact the internal temperature of the chips.


Power consumption is the same regardless of whether thermal paste is installed. It is power consumption that dicates how hot the amp gets overall. Paste is about getting power out of the chip with minimal chip temperature rise.

Excactly. It is the TA3255 chips "internal" temperature I like to lower and this needs a medium called "thermal paste" That's all there is to it.
It helps to "cool" the inerts of that amp with the help of thermal paste and the heat sink (casing)...
That's, what every manufacturer is after, in't ist ?

 

[Doodski]

Excactly. It is the TA3255 chips "internal" temperature I like to lower and this needs a medium called "thermal paste" That's all there is to it.
It helps to "cool" the inerts of that amp with the help of thermal paste and the heat sink (casing)...
That's, what every manufacturer is after, in't ist ?

The name of the game is conduct heat away from the PCB and chip amp. So if you are into MODing then you are on the right track. If you can find a thermal paste with a guarantee of ~8 years life expectancy before breakdown that will be the best.

 

[burkm]

I am not going to "mod" something, just looking, if everything is as it is supposed to be...
If I should need thermal paste, I got some with extended life because I just reinstalled my CPU using it. If needed more for all, I will order some through Amazon...

 

[somebodyelse]

Oh, so I get a big dip when inverting phase, but not at the frequency I chose for crossover. I am new to using a sub and miniDsp etc so followed miniDsp instructions on setting up my Flex. I was a bit confused as to where they got their crossover frequency from in the online guide. I choose 85hz and to be honest it does drop on inversion but only by a few dB. But, at 103hz there’s a massive sharp drop on inversion. So, does that mean I should use 103hz as crossover and that the SVS sub is actually in phase with the V3 monos? All interesting stuff even if I don’t fully understand

Probably best to start a new thread for this as it's not really anything to do with the V3 Mono. You'll be more likely to get people with experience setting up subs with the Flex that way too.

 

[Petrushka]

I've heard lots of weird audiophile words for describing audio, but "nasally glass like" really takes the price. What does that even mean?

Bad speakers?

 

[mike70]

I bet even his wife heard if from the kitchen

and with class AB is like a veil was lifted from the speakers.

Blind test with levelled gain is the scientific tool to check that spectacular differences ... in other way ... only words.

 

[DavidM1]

I bet even his wife heard if from the kitchen

Lol.
There are two possibilities here. 1. The differences are entirely imaginary or 2. The listener was used to something that wasn’t as even in its response.

I posted a vid a few pages ago on aural illusions. Several showed the dependence of what we hear on what we see. One I liked instantly switched the sound of a word from “bear” to “fare” depending on which of two mouths one chose to look at, even though the recording itself was the same throughout.

 

[SMen]

The Shure V15 Type III has the original VN35MR “Super Tracking” stylus. It’s a matter of time for replacing it, so I am prepared to acquire a suitable Jico replacement. The Dual 1229 is a family heirloom piece I inherited from my family. My uncle was an audiophile and he had an all McIntosh separates system with this Dual 1229 turntable. I sent it to Bill Neumann of Fix My Dual in Des Moine, Iowa. Bill is great to work with and his group restored the 50+ year old Dual 1229 idler wheel drive to “factory new” condition. I highly recommend him for purchasing rebuilt Dual turntables or rebuilding classic Dual turntables like the 1219, 1229 and 701.

View attachment 387232 View attachment 387233 View attachment 387234

With balanced connections from the phon stage preamp to the Fosi V3 Mono amps, my system is silent in idle and sounds very musical. I’m enjoying my vinyl.

Cool. I'm a fan of those Jico SAS ... well only the borons which theoretically may well be best in many systems . Yes, just running balanced through everything is working for me.

It is great to read, keeping it in the family, and to see those pics. Thank you.

 

[antcollinet]

Excactly. It is the TA3255 chips "internal" temperature I like to lower and this needs a medium called "thermal paste" That's all there is to it.
It helps to "cool" the inerts of that amp with the help of thermal paste and the heat sink (casing)...
That's, what every manufacturer is after, in't ist ?

Good - but the point I was making is that a high case temperature is not an indication that themal paste is not applied or insufficiently applied. That seems to be a mistake a lot of people are making.

"Wow - this amp feels hot - I'd better take it apart and apply more paste"

 

[renoxd]

I received the 2 units a couple of weeks ago and the mains filter somewhat later. The top covers reach a temperature of about 40 degrees C even if there is no music playing.

Mine reach over 45C when turned ON, without speakers connected. 38 in standby mode. I have asked few questions to Fosi Team and waiting for clarification. If the answers wont be satisfying, I will send them back

 

[Killingbeans]

2. The listener was used to something that wasn’t as even in its response.

I'm again reminded of how my grandmother used to switch off her hearing aids most of the time because of how being deaf had become the new normal. When she could actually hear the sounds from her surroundings, she descibed it as "infernal noise"

 

[totti1965]

YouTube Video from Christian Schwarzbeck in German Language to discuss the polarity problem:

 

[DavidM1]

Mine reach over 45C when turned ON, without speakers connected. 38 in standby mode. I have asked few questions to Fosi Team and waiting for clarification. If the answers wont be satisfying, I will send them back

Others might be able to clarify but I always thought that having an amp on without speakers connected risks damage.

 

[Doodski]

I always thought that having an amp on without speakers connected risks damage.

No damage can happen. It's safe to do. Just remember to shut the unit down upon reconnecting the speakers.

 

[Young Moon]

V3 모노를 분해하고 방열판 전체에 열전도 페이스트를 다시 도포했습니다.

이전에는 방열이 중앙에서만 원형으로 적용되었습니다.

지금은 뜨겁지 않고, 그냥 따뜻할 뿐입니다.

 

[Doodski]

V3 모노를 분해하고 방열판 전체에 열전도 페이스트를 다시 도포했습니다.

이전에는 방열이 중앙에서만 원형으로 적용되었습니다.

지금은 뜨겁지 않고, 그냥 따뜻할 뿐입니다.

Good to hear the temperature is down.

 

[NTK]

Good to hear the temperature is down.

If it is the chassis temperature that goes down, and assuming that the amp chip is generating the same amount of heat, a cooler chassis means that the heat conduction from the amp chip to the chassis is reduced.

 

[Doodski]

If it is the chassis temperature that goes down, and assuming that the amp chip is generating the same amount of heat, a cooler chassis means that the heat conduction from the amp chip to the chassis is reduced.

True or it might be spread over a larger surface area of the sheet metal?

 

[NTK]

If we consider the average temperature of the chassis, a higher average chassis temperature will mean that more heat will be dissipated by the chassis to the environment. Since that heat has to come from the amp, a higher average chassis temperature means that there is more heat conduction from the amp to the chassis.