Fosi Audio V3 Mono Amplifier Review

[norcalscott]

Just a hypothesis, but might Fosi handle the dispatches based on the order in which the surveys (with delivery details) have been received?

Just a hypothesis (and not a particularly good one at that) but a few timestamps from users might help to (dis)prove it

I suspect that the shipments are being organized by the options that were chosen. I work for a HW company and if we had to ship thousands of shipments containing a dozen different combinations, we would organize them in those combination groups to make it more efficient.

It will be interesting to see what the earlier shipments were comprised of. I'm backer ~#157 and haven't received any shipment notification, but I'm getting two amps, the 10A power supply and op amps. Not sure if I have seen where anyone else with that combination was notified.

In any event, they probably should provide an update, but I trust Fosi as a company until given a reason not to trust them. I'm looking forward to getting my amps but have plenty of other summer chores to keep me busy

 

[redstang]

For what it's worth, my backer # was in the 700s, 2 amps with 5a power supplies and 2 op amps. Mine shipped 6/19 and have landed stateside today. Assume they might get delivered this week.

 

[EddNog]

My units have arrived and I’ve come immediately to inform other buyers/owners that the units do not come with thermal interface material between the heatsink and enclosure from the factory:

-Ed

 

[Negatywny]

thats awkward.

 

[Nuigurumi]

With the opamp swapping marketing and sliding mechanism I'm not sure what you'd expect...
Thermal pads are sticky and paste would make a mess.

 

[EddNog]

With the opamp swapping marketing and sliding mechanism I'm not sure what you'd expect...
Thermal pads are sticky and paste would make a mess.

The ZA3 came with factory TIM. The V3 and V3 Mono do not.

-Ed

 

[Toroid]

My units have arrived and I’ve come immediately to inform other buyers/owners that the units do not come with thermal interface material between the heatsink and enclosure from the factory:

View attachment 377142

-Ed

This only matters if you are swapping op amps, correct?

 

[EddNog]

This only matters if you are swapping op amps, correct?

This has nothing to do with op-amps. The heatsink acts as a thermal coupler to the amplifier’s enclosure so that it can utilize the entire enclosure to better dissipate heat from the Texas Instruments amplification chip. Having thermal interface material improves thermal efficiency because the heatsink can pass more heat off to the enclosure, which then transfers heat farther on to the outside air.

-Ed

 

[Sokel]

This has nothing to do with op-amps. The heatsink acts as a thermal coupler to the amplifier’s enclosure so that it can utilize the entire enclosure to better dissipate heat from the Texas Instruments amplification chip. Having thermal interface material improves thermal efficiency because the heatsink can pass more heat off to the enclosure, which then transfers heat farther on to the outside air.

-Ed

Looking at the size of it (you literally hold it in your hand! ) I'm not sure that any heat dissipation has been addressed whatsoever.
Just run the calc I posted very early at this thread to see.

Thermal paste is just a drop in the ocean considering this matter.

 

[EddNog]

Looking at the size of it (you literally hold it in your hand! ) I'm not sure that any heat dissipation has been addressed whatsoever.
Just run the calc I posted very early at this thread to see.

Thermal paste is just a drop in the ocean considering this matter.

Given that, don’t you think the situation warrants taking every possible (reasonable) measure?

-Ed

 

[Sokel]

Given that, don’t you think the situation warrants taking every possible (reasonable) measure?

-Ed

I don't think it will make a difference when things start to stress.
Pic doesn't help but even the surface of the PCB's heatshink does not look this extra smooth (near mirror flat) as it should be.
Have a look at Nilai's heatshink for comparison.

I hope I'll be proven wrong but cost cuts shouldn't include thermals.

 

[EddNog]

I don't think it will make a difference when things start to stress.
Pic doesn't help but even the surface of the PCB's heatshink does look this extra smooth (near mirror flat) as it should be.
Have a look at Nilai's heatshink for comparison.

I hope I'll be proven wrong but cost cuts shouldn't include thermals.

I don’t know about other people’s applications for these little amps. I’m just driving a single KEF LS50 Meta with each one, and the room is medium sized, plus I supplement with a subwoofer. I don’t think I’m going to be pushing these things into thermal deconstruction, or anywhere near that. ¯\_(ツ)_/¯

-Ed

 

[Toroid]

I don’t know about other people’s applications for these little amps. I’m just driving a single KEF LS50 Meta with each one, and the room is medium sized, plus I supplement with a subwoofer. I don’t think I’m going to be pushing these things into thermal deconstruction, or anywhere near that. ¯\_(ツ)_/¯

-Ed

I'm going to be getting loud with some big, inefficient speakers. Perhaps @Fosi Audio could reply to let us know if they recommend thermal paste?

 

[Negatywny]

i really hope they don't cause i paid for completed product not for do it yourself kit, or even apply your thermal paste onto your power amplifier kit without thermal paste in it.

 

[fredreadrick]

Did you get an email upon Fosi sending your package, or did it just arrive without further notice? I am curious since I have two Monos on the way from the original Kickstarter, but have heard nothing since confirming my shipping address and reward.

Got notification email on shipping details on June 17, was tracking it online at given link.

 

[fredreadrick]

Those are the 10a power supplies? I see 4 amps and 2 supplies

Ordered with 5a psu...

 

[fredreadrick]

I suspect that the shipments are being organized by the options that were chosen. I work for a HW company and if we had to ship thousands of shipments containing a dozen different combinations, we would organize them in those combination groups to make it more efficient.

It will be interesting to see what the earlier shipments were comprised of. I'm backer ~#157 and haven't received any shipment notification, but I'm getting two amps, the 10A power supply and op amps. Not sure if I have seen where anyone else with that combination was notified.

In any event, they probably should provide an update, but I trust Fosi as a company until given a reason not to trust them. I'm looking forward to getting my amps but have plenty of other summer chores to keep me busy

Backer #530 here - 4monos with 2- 5a PSUs

 

[Megaken]

But is it getting hot when you use it?

 

[fredreadrick]

But is it getting hot when you use it?

By feel, it's hotter than ZA3....

 

[Bleib]

Let in some air underneath?