Fosi v3 Mono - User Impressions | Owner's Thread

[Sokel]

How can you tell which phase a circuit uses in a house that has a three-phase power supply? In my case we have large old aircon units on separate circuits, and multiple GPO circuits in the house. I'm in Australia which is 240v if that makes a difference.

You can't unless you built it this way right from the beginning.
It's one thing to have separate circuits and another to have completely separate lines you can distribute coming in the house.
I'm in Europe,we have 230V here,we too have large HVAC and stuff at the own circuits but at the same phase.

 

[iLoveCats]

Try disconnecting the input. If it still powers up from standby when you switch the LED it is definitely mains borne (or possibly - though unlikely) radiated)

If not then it is noise on the input. Which could be a grounding issue, or it could be disturbance caused inside your source.

Good call. It's not the Fosi waking itself from bad power filtering. I pulled the balanced input and it didn't turn on with the floor lamp. If I have the inputs connected and the switch on my PRE90 off, the amps don't wake up. I need to try it with the PRE90 on and the D90 DAC off, and then pull one input at a time from the D90 and try that. Takes 10 minutes to reset the auto on each time. I'll try later.

 

[iLoveCats]

I can confirm by the process of elimination and waiting 10 minutes for the amps to reset per component that the culprit for me is a Dayton Audio SPA500 subwoofer amplifier. With the subwoofer amp unplugged I can turn the light switch on and off without the V3 mono amplifiers waking up.

 

[tusc]

I just received my two monos from China yesterday. I have them hooked up to a DRX 3.4 and driving a pair of LSI9s which can go down to 2 ohms. I'm impressed at how much power the V3s can deliver. With the gain switch at 31db, I'm getting SPL levels in the 80 dBs with the volume level on the AVR at midway, sitting from 9 ft away.

 

[Sokel]

I just received my two monos from China yesterday. I have them hooked up to a DRX 3.4 and driving a pair of LSI9s which can go down to 2 ohms. I'm impressed at how much power the V3s can deliver. With the gain switch at 31db, I'm getting SPL levels in the 80s with the volume level on the AVR at midway, sitting from 9 ft away.

View attachment 395083

80s with C weighting is not much,specially if the music you listen too has a bit of bass.

 

[morillon]

80s with C weighting is not much,specially if the music you listen too has a bit of bass.

and speakers in corner...

 

[tusc]

and speakers in corner...

Yeah, this is in the basement HT area and I have limited options. Thank god for Dirac.

 

[DannyBoyNYC]

If anyone wants a FREE 10v Fosi power supply and is able to pick up in central Brooklyn, lower Manhattan or Jersey City ping me. I've got an extra.

 

[Jon L]

Well, shoot, I guess the Aiyima A70 monoblocks run much cooler than Fosi V3 monoblocks.

 

[Old_School_Brad]

I just received my two monos from China yesterday. I have them hooked up to a DRX 3.4 and driving a pair of LSI9s which can go down to 2 ohms. I'm impressed at how much power the V3s can deliver. With the gain switch at 31db, I'm getting SPL levels in the 80 dBs with the volume level on the AVR at midway, sitting from 9 ft away.

View attachment 395083

That’s not much. If it were something more dynamic with bass, you could easily subtract 15-20 dB from that value as the bass / room mode contribution.

 

[Sylvia]

Hi, I really don't mean to trash talk Fosi Audio, but I am just having a very strange experience and wonder if someone can help me out.
I ordered a couple v3 monos and decided to send them back. When I contacted the company they first tried to convince me of selling them in the second hand market instead of sending them back. When I told them I'd rather return them they gave a list of instructions for the return shipping, demanding that I write down on the shipping documents a value of 10€ when the price of the order was actually 450€ - If I don't do this then I will have to pay the import costs myself. But I don't understand why one has to pay for import costs when returning a product.
Is this a common thing?
Isn't it a questionable thing for a company to ask to from a customer to lie in the customs documentation?

 

[Rafaille]

Hi, I really don't mean to trash talk Fosi Audio, but I am just having a very strange experience and wonder if someone can help me out.
I ordered a couple v3 monos and decided to send them back. When I contacted the company they first tried to convince me of selling them in the second hand market instead of sending them back. When I told them I'd rather return them they gave a list of instructions for the return shipping, demanding that I write down on the shipping documents a value of 10€ when the price of the order was actually 450€ - If I don't do this then I will have to pay the import costs myself. But I don't understand why one has to pay for import costs when returning a product.
Is this a common thing?
Isn't it a questionable thing for a company to ask to from a customer to lie in the customs documentation?

This is unfortunately common practice for returns to China. The reason why they are asking you to declare low value is that otherwise they would have to pay import duties and likely go through some additional costly checks at customs. The obvious downside is if your parcel gets lost for whatever reason it will only be insured up to the value you declared. In most cases, it will be fine and your return should be accepted and you will get your money back, but ultimately you rely on international postal services for that to happen, good luck!

 

[Sylvia]

This is unfortunately common practice for returns to China. The reason why they are asking you to declare low value is that otherwise they would have to pay import duties and likely go through some additional costly checks at customs. The obvious downside is if your parcel gets lost for whatever reason it will only be insured up to the value you declared. In most cases, it will be fine and your return should be accepted and you will get your money back, but ultimately you rely on international postal services for that to happen, good luck!

Thanks for your response, I didn't know that. Well I guess I learned my lesson...

 

[RoA]

Thanks for your response, I didn't know that. Well I guess I learned my lesson...

And what have you learned?

 

[Guddu]

Thanks for your response, I didn't know that. Well I guess I learned my lesson...

Generic suggestion….
Buying directly from any of these vendor stores has these issues, and we always have Amazon way if we just wait for product to be released on the platforms that has a bit more protection for buyers.
Any vendor can do pre-sales release on Amazon but I think they avoid.

 

[antcollinet]

And what have you learned?

Don't buy higher value items direct from China.

 

[jayapple]

I didn't expect FOSI to be so popular abroad. Its sales are not very high in China, and I bought it to try for a while before returning it. However, I still keep the stereo V3 amplifier, partly because I might have gotten used to the sound of the V3 amplifier.
The mono power of the V3 mono amplifier is impressive, with one amplifier per channel! It also has much more detail than the stereo V3, but it seems a bit tiring to listen to. The power is high and the sound is loud, with rich details. It's too high-fidelity!

Another reason is that there are too many power supplies, taking up space, and if FOSI releases a 5 channel amplifier with integrated power supplies, I would buy it without hesitation.

 

[Old_School_Brad]

I didn't expect FOSI to be so popular abroad. Its sales are not very high in China, and I bought it to try for a while before returning it. However, I still keep the stereo V3 amplifier, partly because I might have gotten used to the sound of the V3 amplifier.
The mono power of the V3 mono amplifier is impressive, with one amplifier per channel! It also has much more detail than the stereo V3, but it seems a bit tiring to listen to. The power is high and the sound is loud, with rich details. It's too high-fidelity!

Another reason is that there are too many power supplies, taking up space, and if FOSI releases a 5 channel amplifier with integrated power supplies, I would buy it without hesitation.

I'd guess they probably won’t, as they likely couldn’t stay competitive without using the external power brick.

 

[jayapple]

I'd guess they probably won’t, as they likely couldn’t stay competitive without using the external power brick.

Mono do have a lot of competitiveness, and do not interfere with each other. It's also fungible.

But it would be nice to have a super power source that could power multiple mono.

 

[Stoutblock]

I own several V3M amps now. Two for may office system and six in my home theater system. I’ve owned lots of vintage equipment over the years but have weaned myself out of them except for one. I just can’t let go of my Nakamichi System One. Made back in the late 70s and I’ve always wanted one since the first I saw one BITD. I just think it is cool with a very functional industrial design. It took years to collect all the parts but it is one of proud possessions.

The 620 amps are not Nakamichi’s best effort and I’ve rebuilt mine several times over the years. My System One uses two 620 stereo amps and a Nakamichi active crossover to by-amp some ADS L1290 speakers. One of my 620 amps went South a few days ago (again) and I decided to change course. Instead of rebuilding it I got two more V3M amps and installed them on the backside of the front heat sink facia of the 620. Works great and who will know?