Fosi Audio V3 Mono Amplifier Review

[staticV3]

Sorry if this has been covered but how long is the PSU's cable? I'd hope that it would be long enough to be easily hidden behind furniture

The power supply shown in Amir's pictures (JYH23Z-4800500-BF) has a fixed, 116.5cm long DC cable.


However it is unclear which power supply Fosi Audio will end up bundling with the V3 Mono when it will be launched on April 20th.

It may be the same power supply that Amir got with his unit, it may be another.

 

[beeface]

The power supply shown in Amir's pictures (JYH23Z-4800500-BF) has a fixed, 116.5cm long DC cable.

However it is unclear which power supply Fosi Audio will end up bundling with the V3 Mono when it will be launched on April 20th.

It may be the same power supply that Amir got with his unit, it may be another.

Hmm I reckon 2 metres minimum would have been best if the power supply dwarfs the amp itself. Cable slack is a non negotiable

 

[staticV3]

Hmm I reckon 2 metres minimum would have been best if the power supply dwarfs the amp itself. Cable slack is a non negotiable

You will likely be able to buy the V3 Mono without an included power supply, then pair it with a power supply that meets your criteria.

 

[amirm]

Hmm I reckon 2 metres minimum would have been best if the power supply dwarfs the amp itself. Cable slack is a non negotiable

I haven't seen this type of power supply come with much longer cable. There can be losses if you go too long.

 

[RickS]

I haven't seen this type of power supply come with much longer cable. There can be losses if you go too long.

How robust is the power connector retention?

 

[Inertiaman]

I haven't seen this type of power supply come with much longer cable. There can be losses if you go too long.

Losses at 48V DC and 5A are negligible.

I don't know the exact wire gauge used, but with 16awg as an example, you'd drop roughly 0.15V per meter. So at the amp socket you'd get 47.85 or so w/ the current cable, and close to 47.5V with a 3 meter cable. Hardly a concern.

Voltage drop can be a concern on automobile amplifiers, where the voltage is 4X lower and current 10x higher, and the amplifiers are voltage sensitive around the 12V threshold. But in this V3 Mono scenario, where the amps are stable and function fine far below 48V (albeit with some slight power output loss), the less-than-1V voltage drop over a power supply cord would be immaterial.

I suspect the cord length is determined more on perceived use case requirement, and/or costs, than any concern over losses.

 

[Billy Budapest]

Amazing performance for the price. Most measurements are not SOTA, but are close.

 

[dzerig]

Is it clear from looking at the power draw of the various doohickeys that one power brick will power 2 amplifiers as cleanly as Amir measures with 1 amplifier? And how do you connect two amplifiers to the brick?

 

[staticV3]

Is it clear from looking at the power draw of the various doohickeys that one power brick will power 2 amplifiers as cleanly as Amir measures with 1 amplifier?

No.

And how do you connect two amplifiers to the brick?

 

[Bruce Morgen]

Losses at 48V DC and 5A are negligible.

I don't know the exact wire gauge used, but with 16awg as an example, you'd drop roughly 0.15V per meter. So at the amp socket you'd get 47.85 or so w/ the current cable, and close to 47.5V with a 3 meter cable. Hardly a concern.

You can make an extension cord from 18 or 16 AWG zip cord. Appropriate male and female connectors are available inexpensively and require no soldering -- I've been using them for years.

 

[Talisman]

You can make an extension cord from 18 or 16 AWG zip cord. Appropriate male and female connectors are available inexpensively and require no soldering -- I've been using them for years.

In reality, if the power connector is the classic 5.5/2.1 that is generally found in their products, there are already ready-made extensions on Amazon

 

[Toslink]

It's more likely a 2.5mm x 5.5mm, a format I've seen in higher power low-voltage DC applications. But, this is just speculation on my part. Perhaps Amir can chime in here based on his review sample.

 

[Bruce Morgen]

You can make an extension cord from 18 or 16 AWG zip cord. Appropriate male and female connectors are available inexpensively and require no soldering -- I've been using them for years.

It's more likely a 2.5mm x 5.5mm, a format I've seen in higher power low-voltage DC applications. But, this is just speculation on my part. Perhaps Amir can chime in here based on his review sample.

Yup, that's the typical chip amp power connector spec.

 

[Talisman]

 

[Ze Frog]

View attachment 361219

Or some heavy duty Velcro with adhesive backing on the backside of unit if people are anxious about cable length. Either way, easy solutions to be had.

 

[Golf]

However it is unclear which power supply Fosi Audio will end up bundling with the V3 Mono when it will be launched on April 20th.

As it is unclear whether the then purchasable amp itself will be different from a certain pre-launch unit reviewed by Amir.

 

[brunes]

Amazing performance for the price. Most measurements are not SOTA, but are close.

Not trying to be inflammatory, genueinly interested... where are the differences or what needs to be improved? Is it across everything, Just more power?
Better power vs distortion or more stable reactive load?

 

[Bruce Morgen]

Question for Fosi Audio (or anyone else who happens to know): Are those 2200mFd 63VDC electrolytic capacitors connected in shunt across the incoming DC to provide additional filtering/reservoir effect or do they reside elsewhere in the circuit?

 

[MCH]

Question for Fosi Audio (or anyone else who happens to know): Are those 2200mFd 63VDC electrolytic capacitors connected in shunt across the incoming DC to provide additional filtering/reservoir effect or do they reside elsewhere in the circuit?

From tpa3255 datasheet:

The large capacitors used in conjunction with each full-bridge, are referred to as the PVDD Capacitors. These capacitors should be selected for proper voltage margin and adequate capacitance to support the power requirements. In practice, with a well designed system power supply, 1000 μF, 80 V supports most applications.
The PVDD capacitors should be low ESR type because they are used in a circuit associated with high-speed switching.

 

[Ajax]

I'm gonna get 7 of these, that 8 channel Topping DAC and a subwoofer.

These are obviously great little amps but a "cleaner" solution with the same performance for not much more $ would be a Buckeye 6 or 8 channel 252 Hypex.

Buckeye Amps

Buckeye Amps utilizes the most advanced audio amplifier technologies available. Authorized seller for Hypex and Purifi Class D amplifiers. Based in the US. Free shipping and worldwide service!

www.buckeyeamp.com