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Fosi Audio V3 Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 10 2.0%
  • 2. Not terrible (postman panther)

    Votes: 44 8.6%
  • 3. Fine (happy panther)

    Votes: 239 46.9%
  • 4. Great (golfing panther)

    Votes: 217 42.5%

  • Total voters
    510
Has anyone been able to purchase the 2024 version with volume adjustable preamp outputs from Amazon? I’m just wondering if it is only available from their own website.
 
Hi. I have fosi v3 with 48v power supply. My system is :dac smsl d300 , streamer wii mini and dali Oberon 1 speakers. I wonder if I can connect with my buffer b1 preamp to fosi v3.
 
I was sceptical but yup, bananas fit - yay
Second question - if I run it powered on 24/7, does it get warm with zero audio input ? Thinking I'll power-on the miniDSP Flex used as my pre & control volume from that . . .

I leave mine on 24/7 and it runs lukewarm with zero input for me. It is in a cabinet with network equipment that also runs warm.

I did run it out in the open air for a few days, and at idle when left "on" it was cool to the touch.
 
I received my V3 today, and hooked up to a RPi steamer (moOde OS) with a smsl su-1 dac.
Need to check still at what volume/% i should set the output of the source. Should that be 100%/0db, or is it better to set it somewhat lower?

Herewith a picture of the temporary setup...
1000023752.jpg
 
I received my V3 today, and hooked up to a RPi steamer (moOde OS) with a smsl su-1 dac.
Need to check still at what volume/% i should set the output of the source. Should that be 100%/0db, or is it better to set it somewhat lower?

Herewith a picture of the temporary setup...View attachment 367249

I think the best is to bypass any "volume" until the V3 potentiometer.
Maybe the DAC have a setting to power off the volume management.
 
I think the best is to bypass any "volume" until the V3 potentiometer.
Maybe the DAC have a setting to power off the volume management.
Yes, I've set them all to bypass or fixed. The V3 is now the main volume regulator.

Great sound so far from the connected Q Acoustics 2020 speakers, I'll try my Revel M105s as well tomorrow....
 
I just got one, $71 Fire Sale Amazon

I don't even know which PS it comes with, if any. I've hoarded enough to find an old one and adapt it...

 
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does anyone with confidence know, if new ZA3 has higher gain then V3?
 
Hi everyone,

Hope someone can help me please. I just purchased this amp to power two bass shaker transducers. They are rated at 50w RMS / 100w Max at 4ohms.

I'm using the included 32v 5a power supply on the amp and am wondering how far I can go with the volume control as I don't want to damage anything.

Amp specs at 32v are 2x125w max (unsure about RMS, can't find anything online) and have read the volume dial is logarithmic rather than linear, as I was limiting myself to 40% 10 o'clock position which isn't very loud haha

My source is a PC (Realtek ALC1200 onboard soundcard) - which I believe is 1.1vrms output, so I'm thinking I can really drive that volume dial round as much as I want?

1.1 x 20v gain = 22v
22v = 50w approx?????

Can someone help me please. I really want to crank the volume up!

so....how far can that dial go? :)

Thanks!!!!!
 
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Hi everyone,

Hope someone can help me please. I just purchased this amp to power two bass shaker transducers. They are rated at 50w RMS / 100w Max at 4ohms.

I'm using the included 32v 5a power supply on the amp and am wondering how far I can go with the volume control as I don't want to damage anything.

Amp specs at 32v are 2x125w max (unsure about RMS, can't find anything online) and have read the volume dial is logarithmic rather than linear, as I was limiting myself to 40% 10 o'clock position which isn't very loud haha

My source is a PC (Realtek ALC1200 onboard soundcard) - which I believe is 1.1vrms output, so I'm thinking I can really drive that volume dial round as much as I want?

1.1 x 20v gain = 22v
22v = 50w approx?????

Can someone help me please. I really want to crank the volume up!

so....how far can that dial go? :)

Thanks!!!!!
It is measured here at 85W with the 32V PSU (1% THD), not 125W.

The gain is also measured at 26dB = 20x, so as you say 22V output from 1.1V input.

P = VxV/R = 121W into 4ohm - so more than the amp can deliver. For a max of 85W (to avoid the amp clipping) you want to output no more than about 18V,

We can't say how far you can turn the dial, since we don't know how the volume varies with dial position.

Normally (with speakers) we'd just say if you can hear distortion - turn it down. No idea if this approach works with a shaker.

So I think your best bet is to measure the level out of the PC with a full scale test tone, and turn that down until it is 0.9V or lower.
 
It is measured here at 85W with the 32V PSU (1% THD), not 125W.

The gain is also measured at 26dB = 20x, so as you say 22V output from 1.1V input.

P = VxV/R = 121W into 4ohm - so more than the amp can deliver. For a max of 85W (to avoid the amp clipping) you want to output no more than about 18V,

We can't say how far you can turn the dial, since we don't know how the volume varies with dial position.

Normally (with speakers) we'd just say if you can hear distortion - turn it down. No idea if this approach works with a shaker.

So I think your best bet is to measure the level out of the PC with a full scale test tone, and turn that down until it is 0.9V or lower.

Thanks very much
 
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First post here but just wanted to share my experience. Connected Wiim pro>Aune dac with Sparkos opamp>V3>Elac unifi 2.0 ub52. Sounded good but a bit dry. Added my old Aiyima T9 as a preamp via aux out to V3 and what a magnificent difference it made. Bigger sound stage, deeper bass the list goes in. Haven't stopped listening. Enjoy
 
First post here but just wanted to share my experience. Connected Wiim pro>Aune dac with Sparkos opamp>V3>Elac unifi 2.0 ub52. Sounded good but a bit dry. Added my old Aiyima T9 as a preamp via aux out to V3 and what a magnificent difference it made. Bigger sound stage, deeper bass the list goes in. Haven't stopped listening. Enjoy

Well, the Aune DAC seems to be a "standard" DAC (I mean surely transparent to the source, or very close) but that Aiyima have a tube buffer and tone controls. I don't know it really, but I can suppose you're hearing higher THD and gain on certain frequencies, not really a "better hifi" sound. Measurements can show the real situation, I'm only guessing.

I mean that maybe an EQ with the Aune can have that "sauce" in the sound you like with better transparency and detail.

This "mental exercise" don't pretend to criticize your experience or taste ... is only to try to find the causes about it. That's the enjoyment here, normally :)
 
No problem Mike. Only posted to inspire others to have a crack at mixing up a few of these devices many of us have in the drawers. That's part of the fun.
 
I've had my Fosi up and running for about a month and am quite pleased with it's performance. This morning I inadvertently managed to spill a couple tablespoons of hot coffee through it's vents while it was running. The little Fosi shut down instantly and I feared the worst outcome. I turned the amp off and dried the outside with a towel and used a can of compressed air to blow out the coffee that was left inside. To my complete amazement the hardy little Fosi sprung back to life and has been playing a couple hours now with no sign of a problem.
Kudos to Fosi Audio for going above and beyond and including a highly functional spilled coffee safety device on the V3.
 
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