So after having the 2 units for a few month, i wanted to give and share my experience.
Equipment Used for evaluation ;
Amps: Primaluna Evo 200 , Spendor D40 , Fosi Audio V3 Stereo And Bottlehead Stereoumour II
Speakers -> Kef LS50 Meta , Magnepan LRS , Tang Band D-4 and Harbeth m30.2XD
Source And preamp -->Chord Mojo , Metrum Nos mini DAC Octave, Audiolab MDAC+ and passive preamp
* cd's and DAP used a source no streaming or turtables
The V3 Mono were used in their ''Stock" form ( op-amps ) and with 2x 48/5A Power Supply
I tried the RCA and XLR Inputs
The XLR cables i have are 5' long per side and short 25cm speaker cables were used
The first thing i noticed when suing the XLR inputs, was that some users might be reaching the volume knob to get some sound pressure.
With 20db of gain in XLR mode , a quality preamp with at least 10db of gain should be sufficient.
Me personally, it did not bother me at all.
I like passive pot or preamps with no gain ( less noise )
I Was using The Balanced outputs of my mdac+ in preamp+dac mode. This unit does not add any gain via the preamp section. It's maximum output is around 4.5volts
i think the sound was very satisfactory with no artifices. neutrality comes to mind . The KEF LS50 Meta's did not sound lean or lacked in dynamics in any way.
I then tried the RCA inputs with my chord mojo used as a preamp+dac with the gain set at 31db.
Now curiously i was getting a little more ''jump factor'' and the sound became less ''polite'' compared to the MDAC+
What i also appreciate about the RCA inputs is that you can switch the gain to 25db for better SINAD and get less digital ''distortion'' or less voltage from the source.
I could now raise more the volume to double green (balls color) in the mojo to get a small but perceivable fuller sound.
Last DAC But Not the least was the metrum octave nos mini dac which i think it's a good (original version).
a ifi ipurifier2 was used to feed the digital input
A passive potentiometer with no gain was used before the V3's.
This is the configuration that i have enjoyed the most. I was hearing good dynamics the bass density and presence was palpable and voices came out in a very natural way !
Using the magnepan as main speakers the sound was good and clear but i did not want to push the amps to hard in this situation
I think they can do a good job overall but on the long term, i would get a different amp for the LRS.
Harbeth M30.2 Sounded Very Clean and very ''monitor'' like kind of sound. Maybe a bit ''dry'' for me but again very respectable presentation it was when we consider the price of these units. I was getting good depth in the soundstage and a good ''flow'' in the presentation of sound.
Tonal balance was very accurate also
Now comparing them to my fosi v3 stereo , i felt that the mono version was just imaging a little better.
Everything felt a bit taller and larger but not by much. Mono's seem more open and crisp but marginally .The V3 Stereo is more laid back and gentle with good musicality. Opaque comes to mind in a good way.
Against the tube amps, it's a matter of what kind of sound signature you are after. Tubes, for me, offer better soundstage and tonality in general.
i get better idea of where the musicians are. I sit about 6 feet from my speakers semi-near field so the lower wattage amplifiers are enough for me
But i did appreciate the cleanliness and control of the Fosi's over my tube amps. Some style of Music really do benefit from solid state vs tubes i think.
These amplifiers have the capacity to reveal what you are feeding them upstream. They are ''transparent'' enough to differentiate different DAC's and they won't be limiting the potential of your sound system (to a certain point). Upgrading your Dac's and Speakers before the amps is another way of reformulating the sentence.
If you are starting your journey into the hi-fi world and want to invest in good clean amps at an affordable price, i would start here and put most of your investment on the speakers.
I did find that they ran a little ''hot'' more so than my V3 stereo but again not an issue for me. As long as they are reliable it should be OK
So to conclude i think that these amps offer a lot of value. So the high wattage is there if needed , excellent SINAD, XLR and RCA inputs with swappable op-amps and switchable gain. They should also be recommendable if you are into home cinema and are in a situation where you need many amps for let's say a 5.1 configuration.
The Amps just get out of the way and they amplifies the signal in a respectful manner with no frills.
The ''minus'' for me would still be the cramped and small binding posts. The only good option is to use banana plugs. bare wires of lower gauge wont fit . Spades is a good middle option but not enough surface contact and also a little tight still.
Next step for me will be to change the op-amps and assess the different sound signatures if any.
Also a matching preamplifier from Fosi would be great !
thx
Equipment Used for evaluation ;
Amps: Primaluna Evo 200 , Spendor D40 , Fosi Audio V3 Stereo And Bottlehead Stereoumour II
Speakers -> Kef LS50 Meta , Magnepan LRS , Tang Band D-4 and Harbeth m30.2XD
Source And preamp -->Chord Mojo , Metrum Nos mini DAC Octave, Audiolab MDAC+ and passive preamp
* cd's and DAP used a source no streaming or turtables
The V3 Mono were used in their ''Stock" form ( op-amps ) and with 2x 48/5A Power Supply
I tried the RCA and XLR Inputs
The XLR cables i have are 5' long per side and short 25cm speaker cables were used
The first thing i noticed when suing the XLR inputs, was that some users might be reaching the volume knob to get some sound pressure.
With 20db of gain in XLR mode , a quality preamp with at least 10db of gain should be sufficient.
Me personally, it did not bother me at all.
I like passive pot or preamps with no gain ( less noise )
I Was using The Balanced outputs of my mdac+ in preamp+dac mode. This unit does not add any gain via the preamp section. It's maximum output is around 4.5volts
i think the sound was very satisfactory with no artifices. neutrality comes to mind . The KEF LS50 Meta's did not sound lean or lacked in dynamics in any way.
I then tried the RCA inputs with my chord mojo used as a preamp+dac with the gain set at 31db.
Now curiously i was getting a little more ''jump factor'' and the sound became less ''polite'' compared to the MDAC+
What i also appreciate about the RCA inputs is that you can switch the gain to 25db for better SINAD and get less digital ''distortion'' or less voltage from the source.
I could now raise more the volume to double green (balls color) in the mojo to get a small but perceivable fuller sound.
Last DAC But Not the least was the metrum octave nos mini dac which i think it's a good (original version).
a ifi ipurifier2 was used to feed the digital input
A passive potentiometer with no gain was used before the V3's.
This is the configuration that i have enjoyed the most. I was hearing good dynamics the bass density and presence was palpable and voices came out in a very natural way !
Using the magnepan as main speakers the sound was good and clear but i did not want to push the amps to hard in this situation
I think they can do a good job overall but on the long term, i would get a different amp for the LRS.
Harbeth M30.2 Sounded Very Clean and very ''monitor'' like kind of sound. Maybe a bit ''dry'' for me but again very respectable presentation it was when we consider the price of these units. I was getting good depth in the soundstage and a good ''flow'' in the presentation of sound.
Tonal balance was very accurate also
Now comparing them to my fosi v3 stereo , i felt that the mono version was just imaging a little better.
Everything felt a bit taller and larger but not by much. Mono's seem more open and crisp but marginally .The V3 Stereo is more laid back and gentle with good musicality. Opaque comes to mind in a good way.
Against the tube amps, it's a matter of what kind of sound signature you are after. Tubes, for me, offer better soundstage and tonality in general.
i get better idea of where the musicians are. I sit about 6 feet from my speakers semi-near field so the lower wattage amplifiers are enough for me
But i did appreciate the cleanliness and control of the Fosi's over my tube amps. Some style of Music really do benefit from solid state vs tubes i think.
These amplifiers have the capacity to reveal what you are feeding them upstream. They are ''transparent'' enough to differentiate different DAC's and they won't be limiting the potential of your sound system (to a certain point). Upgrading your Dac's and Speakers before the amps is another way of reformulating the sentence.
If you are starting your journey into the hi-fi world and want to invest in good clean amps at an affordable price, i would start here and put most of your investment on the speakers.
I did find that they ran a little ''hot'' more so than my V3 stereo but again not an issue for me. As long as they are reliable it should be OK
So to conclude i think that these amps offer a lot of value. So the high wattage is there if needed , excellent SINAD, XLR and RCA inputs with swappable op-amps and switchable gain. They should also be recommendable if you are into home cinema and are in a situation where you need many amps for let's say a 5.1 configuration.
The Amps just get out of the way and they amplifies the signal in a respectful manner with no frills.
The ''minus'' for me would still be the cramped and small binding posts. The only good option is to use banana plugs. bare wires of lower gauge wont fit . Spades is a good middle option but not enough surface contact and also a little tight still.
Next step for me will be to change the op-amps and assess the different sound signatures if any.
Also a matching preamplifier from Fosi would be great !
thx
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