Fosi chip Amp

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rollo

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Fosi chip Amp
« on: 9 Apr 2024, 01:10 pm »
Not a Dealer for them. Very impressive products cheap. Fosi Audio

charles

Alfi

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Re: Fosi chip Amp
« Reply #1 on: 9 Apr 2024, 11:04 pm »
Hi Charles,
Which Fosi model amp ?

mzbrahce

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Re: Fosi chip Amp
« Reply #2 on: 9 Apr 2024, 11:39 pm »
I use the Fosi subwoofer amp to power my version of the bucket sub.
https://www.transcendentsound.com/bucket-sub.html
It works well at low to moderate levels.
(My bucket sub has a 3/4" thick baltic birch baffle added to the top and 4 each 1" dowel rods attached to the baffle, running down the side of the bucket and imbedded in the concrete bottom.  I added modeling clay to fill in the gaps between dowels and the bucket side and lined the bucket sides with No-Res.)

Water Dog

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Re: Fosi chip Amp
« Reply #3 on: 10 Apr 2024, 01:29 am »
I bought one of their V3 amps for a desktop setup. For the price of admission I figured why not. I'm impressed... It does everything I need it to. I'm only using the 32V power supply, so it would probably run out of juice in a larger setting. Works great for near field!  :thumb:

Letitroll98

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Re: Fosi chip Amp
« Reply #4 on: 10 Apr 2024, 11:53 am »
I'd guess Fosi might have a dozen different amps?  Please dear sir, which model?

garyalex

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Re: Fosi chip Amp
« Reply #5 on: 10 Apr 2024, 02:52 pm »
I'm using two Fosi ZA3 amps as monoblocs.  They're driving Magnepan LRS+ speakers.  I have them connected to a Cary SLP-05 preamp.  I know - using a pair of $130 amps with this preamp seems ridiculous.  But the sound says otherwise.  These things are amazing. 

rollo

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Re: Fosi chip Amp
« Reply #6 on: 10 Apr 2024, 03:18 pm »
I'd guess Fosi might have a dozen different amps?  Please dear sir, which model?

ZA3 bridged to mono with 48V power supply. Thinking trying a Angela.Gilbet Yeung power supply. Waiting for V3 mono amps.

charles

Jon L

Re: Fosi chip Amp
« Reply #7 on: 11 Apr 2024, 02:20 am »
I'm using two Fosi ZA3 amps as monoblocs.  They're driving Magnepan LRS+ speakers.  I have them connected to a Cary SLP-05 preamp.  I know - using a pair of $130 amps with this preamp seems ridiculous.  But the sound says otherwise.  These things are amazing.

Sparkos opamps yet?

garyalex

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Re: Fosi chip Amp
« Reply #8 on: 11 Apr 2024, 02:55 pm »
Sparkos opamps yet?

No.  I decided to try something less expensive.  I installed a pair of MUSES8820 opamps.  $7.85 each at Mouser.  The change was subtle but I'm hearing (or imagining) a slightly warmer presentation.

rollo

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Re: Fosi chip Amp
« Reply #9 on: 11 Apr 2024, 04:18 pm »
Texas Instruments, Burson make good ones as well. My effort would be towards a better power supply first. Maybe a tube regulated one.

charles

garyalex

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rollo

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Re: Fosi chip Amp
« Reply #11 on: 11 Apr 2024, 06:00 pm »

listenermark

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Re: Fosi chip Amp
« Reply #12 on: 16 Apr 2024, 03:04 pm »
I purchased a Fosi B20A Pro as a temporary replacement for an integrated amp that is being serviced.  This is my first experience with these new little class D amps.  Out of the box it sounded very bright and thin, but this thing has tone control so no problem....but after cutting the treble a bit it sounded worse.  It seems the treble control cuts mids more than highs, so after cutting the treble I had a scooped out middle and piercing highs.  So, I zeroed out the tone control and toed out my monitors a bunch (I also let the amp run for a few days and added the 48v power supply.)  Now the system sounds great, tons of detail, really clean channel seperation, and muscular bass.  Is burn in on a solid state amp a real thing?  Does the power supply affect sonics?  I don't know, but something happened and I like it.

rollo

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Re: Fosi chip Amp
« Reply #13 on: 16 Apr 2024, 07:57 pm »
I purchased a Fosi B20A Pro as a temporary replacement for an integrated amp that is being serviced.  This is my first experience with these new little class D amps.  Out of the box it sounded very bright and thin, but this thing has tone control so no problem....but after cutting the treble a bit it sounded worse.  It seems the treble control cuts mids more than highs, so after cutting the treble I had a scooped out middle and piercing highs.  So, I zeroed out the tone control and toed out my monitors a bunch (I also let the amp run for a few days and added the 48v power supply.)  Now the system sounds great, tons of detail, really clean channel seperation, and muscular bass.  Is burn in on a solid state amp a real thing?  Does the power supply affect sonics?  I don't know, but something happened and I like it.

   They need break in. Yes a better power supply sounds better. I like a 10 A one. Wait til you reach 300 than 500 hours. gonna be very happy.

charles

VinceT

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Re: Fosi chip Amp
« Reply #14 on: 17 Apr 2024, 01:04 pm »
I got the 20A for the office and sounded bad. My employees used it quite a bit and once broken in sounded surprisingly decent for the money.

Makes me curious about the mono blocks with op amp upgrade. Add a tube pre in the chain my be surprising.