Op-Amp rolling with Fosi V3 Mono.
Above are the OP-Amps that Fosi has tested in the V3 Mono. I have some JRC Muses02 on order and will be discussed when I can test them, but I was able to also test two op-amps that are not on the list. The OPA0627AU and the SX45B will be reviewed.
Above is a short Fosi Audio video on the different positions for the placement of the three different op-amp sockets in the V3 Mono (V3M). For this review I used two budget op-amps the OPA0627AU which can be found for about $8 to $10 each on eBay and AliExpress. In this case I used four op-amps in positions two and three. This resulted in some improvement in the bass and the treble dynamics over the stock NE5532. I have gone back and forth listening and prefer the 627AU chips. I am not sure that there is enough improvement in sound quality (sq) to pay the approximate $40 for the chips.
View attachment 627-close-final-web.jpg
As you can see by the picture, I did not replace socket one on the board. If you are going to use the balanced inputs, I would also replace this op-amp.
I also tested a discrete op-amp the SX45B that I had very good luck with on the Fosi ZA3 amp. I have listened for endless hours on the ZA3 with this op-amp and was very excited to see how it would sound in the V3M. Unfortunately, after about an hour of testing it started to have some low-end distortion and I decided that for what ever reason there is some thing in the V3M that caused this low bass thump. I quickly changed these op amps out of the units and reinstalled the 627AU op amps.
View attachment SX45-op-amp-Fosi-web-low.jpg
As you can see with the SX45B I used only socket two on the board. To be safe, I would only use the op-amps that are on the list posted in the beginning of this post. After I receive my Muse02 op-amps I will post my impressions. Hopefully for Black Friday I will get a set of SS3602 chips when they go on sale.
For the price of $280, which is two Fosi V3M amps and two 48V 5A power bricks, you can get your foot in the door of mono blocks. With the ability to tailor the sound to your personal taste, for a reasonable cost, they are a great buy.
Above are the OP-Amps that Fosi has tested in the V3 Mono. I have some JRC Muses02 on order and will be discussed when I can test them, but I was able to also test two op-amps that are not on the list. The OPA0627AU and the SX45B will be reviewed.
Above is a short Fosi Audio video on the different positions for the placement of the three different op-amp sockets in the V3 Mono (V3M). For this review I used two budget op-amps the OPA0627AU which can be found for about $8 to $10 each on eBay and AliExpress. In this case I used four op-amps in positions two and three. This resulted in some improvement in the bass and the treble dynamics over the stock NE5532. I have gone back and forth listening and prefer the 627AU chips. I am not sure that there is enough improvement in sound quality (sq) to pay the approximate $40 for the chips.
View attachment 627-close-final-web.jpg
As you can see by the picture, I did not replace socket one on the board. If you are going to use the balanced inputs, I would also replace this op-amp.
I also tested a discrete op-amp the SX45B that I had very good luck with on the Fosi ZA3 amp. I have listened for endless hours on the ZA3 with this op-amp and was very excited to see how it would sound in the V3M. Unfortunately, after about an hour of testing it started to have some low-end distortion and I decided that for what ever reason there is some thing in the V3M that caused this low bass thump. I quickly changed these op amps out of the units and reinstalled the 627AU op amps.
View attachment SX45-op-amp-Fosi-web-low.jpg
As you can see with the SX45B I used only socket two on the board. To be safe, I would only use the op-amps that are on the list posted in the beginning of this post. After I receive my Muse02 op-amps I will post my impressions. Hopefully for Black Friday I will get a set of SS3602 chips when they go on sale.
For the price of $280, which is two Fosi V3M amps and two 48V 5A power bricks, you can get your foot in the door of mono blocks. With the ability to tailor the sound to your personal taste, for a reasonable cost, they are a great buy.