Fosi P4+V3s Gain

[Goofy]

Hello everyone,
I just picked up a Fosi P4 + V3 Monos combo (I skipped the ZP3 due to the well-known volume control issues). The P4 preamp offers selectable gain at 3, 6, and 9 dB, while the V3 Monos can be set at 19 or 25 dB.
What would be the optimal gain combination from a performance standpoint? What are the pros and cons of running each component at lower vs. higher gain settings? For context, my speakers are Amphion Argon 0s, and the setup is in a fairly small room.
Thanks in advance for your insights!

---

 

[AnalogSteph]

Honestly, you could leave both at maximum and I would not consider it at all excessive - after all, you're only looking at 34 dB like that, which still falls 5-6 dB short of even a smallish classic integrated amplifier, plus you didn't explicitly say you had a desktop setup, plus small speakers of moderate sensitivity. I'd say try that and see where the volume pot ends up at normal listening volume, if it's like 10-11 o'clock that would already be perfect. What's your definition of a "fairly small room" (area, listening distance)? What are you using for sources, in playback volume normalization being used?

The Argon 0 is 1 k€ a piece for a 4.5" rated -6 dB at 50 Hz? Oof. Small high-end passives like that just aren't good value in a 2.0 system. At the desktop you still have a realistic chance of EQing the living daylight out of the low end after measurement, with growing distance that becomes an increasingly risky proposal.

 

[Goofy]

Honestly, you could leave both at maximum and I would not consider it at all excessive - after all, you're only looking at 34 dB like that, which still falls 5-6 dB short of even a smallish classic integrated amplifier, plus you didn't explicitly say you had a desktop setup, plus small speakers of moderate sensitivity. I'd say try that and see where the volume pot ends up at normal listening volume, if it's like 10-11 o'clock that would already be perfect. What's your definition of a "fairly small room" (area, listening distance)? What are you using for sources, in playback volume normalization being used?

The Argon 0 is 1 k€ a piece for a 4.5" rated -6 dB at 50 Hz? Oof. Small high-end passives like that just aren't good value in a 2.0 system. At the desktop you still have a realistic chance of EQing the living daylight out of the low end after measurement, with growing distance that becomes an increasingly risky proposal.

Hi, thanks for the reply.
My sources are a Topping E30II DAC (fed by a CD transport) and a Technics SL-1200 MK2 with various cartridges through a Fosi BOX X5. The room is about 14 m² (my studio). It’s not a desktop setup but a regular hi-fi installation, with the listening position about 2 meters away.

I tried running everything at the lowest gain settings (3 dB on the preamp and 19 dB on the power amps), and I get sufficient sound pressure with the Topping at around 10–11 o’clock on the volume. With the turntable, I naturally have to turn it up a bit more. Compared to a 6/19 configuration, I find that using the lower gain allows for more volume range on the dial and gives me a sense of better control.

I haven’t tried the 9/25 configuration, but I suspect the volume would already be too high at around 8/9 o’clock.

The Argon 0s retail for €600 each, with a much lower street price, and I've owned them for a while. I’m aware of the limitations in the low end. Since I mainly listen to acoustic music, I’m not really looking for extended end impactful bass — and my listening room wouldn’t accommodate it anyway.

 

[Goofy]

(my studio).

EDIT: (my studio) = (my home office)

 

[AnalogSteph]

My sources are a Topping E30II DAC (fed by a CD transport) and a Technics SL-1200 MK2 with various cartridges through a Fosi BOX X5. The room is about 14 m² (my studio). It’s not a desktop setup but a regular hi-fi installation, with the listening position about 2 meters away.

OK, your CD setup in particular could easily be adding 10 dB or more to the kind of levels I was previously assuming (which would have been a computer-based setup with playback volume normalization)... that's more than the difference between a desktop setup and yours.

I tried running everything at the lowest gain settings (3 dB on the preamp and 19 dB on the power amps), and I get sufficient sound pressure with the Topping at around 10–11 o’clock on the volume. With the turntable, I naturally have to turn it up a bit more.

Then I would suggest lowering output volume levels on the E30 II to better match turntable output, and turning up preamp gain accordingly in return, so both are in a nice and comfortable range.

Compared to a 6/19 configuration, I find that using the lower gain allows for more volume range on the dial and gives me a sense of better control.

Understandable. Just make sure you don't run out of volume on high dynamic range material. (My go-to testing material is ca. late-'90s recordings of Mahler symphonies.)

I can still vividly recall the complaints of folks with traditional hi-fi amps and CD players ca. 2006. The loudness war was in full swing, but the gear was still dimensioned for vinyl plus 6 dB to spare like it had been since the 1980s. It was completely normal to be stuck in the 8:30-9:00 range, with potentially degraded channel balance.