Reference Four - Audiophile Acoustics for the Audio Elite.
Our Reference series have always been about that little extra, the added experience that is hard to pinpoint, but that makes the sound more sophisticated and refined.
Making the heritage appear clearly. Over-sized products can be applied in a wide range of configurations, even those not intended at first. We have always taken great pride in meticulous R&D to provide premium products, but it has also been a misconception that B2 Audio products might not have been designed with SQ as a cornerstone.
The Ref Four is a statement to show the contrary. It took numerous prototypes and revisions to ensure it would be catering to the purists and audio elite. The Reference project has taken almost 2 years to come to a working design that meets our expectations. The profile of the amplifier is more conservative, but that can’t be said for what’s inside. This amplifier is provided without compromise, focusing on dynamics, headroom, and overall sound quality. Renown component manufacturers such as Mcap, Nichicon, Burr Brown, & IR have been used to fulfill the stringent component level specifications required for this project.
There will always be comparisons to certain brands, but looking at the unique aspects of the Ref Four:
*A heatsink with better heat dispersion, meaning you don't need fans in the amp (big no no in sq amps).
*Mcap capacitors and burr brown op amps coupled with the finest caps from Nichicon. The cost increase of these compared to no name can easily be 150 times more per unit.
*High precision hand mounted and matched mosfets from International Rectifier, where others use ordinary cheaper Philips screws, we purchased our own Allen head as it not only looks nicer, but it also allows for better mounting.
*Custom speced power supply cover. This may appear that it is for looks only, but there is again a huge cost related to it as it needs to have a particular surface area allowing the torroid to not overheat, and offers a slight added performance feature as well.
*Class AB to Class A bias mode. Meaning you can drive the amplifier in a full open mosfet configuration to achieve an even better sound if needed.
*1 ohm stereo option. Due to all the upgrades to the amplifier, the Ref Four is able to run at 1 ohm stereo, this is actually where the amplifier really comes alive and impressed us. It was nearly a day & night scenario. Not saying we weren't impressed by 4 ohm, but there was such a huge difference from 4 ohms to 1 ohm that was nearly unbelievable.
The amplifier also comes in a nice cloth cover inside an attractive gift box.
Circuit Configuration: Class A / Class AB (bias)
Frequency Response: 10 Hz ~ 30 KHz
Signal to Noise Ratio: > 95 dB
Input Sensitivity: 8 V ~ 0.1 V
Input impedance: 47 Kohm
Low Pass Crossover: 40 Hz ~ 4 KHz
High Pass Crossover: 40 Hz - 4 KHz
Band pass crossover: 40 Hz - 4 Khz
Total Harmonic distortion: <0.15% (1 Khz)
fuse rating: 120a (3 x 40a)
power terminal gauge: 4 GA
dimensions: 15.35” x 8.64“ x 2.56” / 390 mm x 219.5 mm x 65 mm
Continuous output power (RMS)
(12.5 V < 0.2% THD) (13.8 V < 0.2% THD) (14.4 v < 1 % thd)
Power @ 4 Ω: 75 W x 4 - 100 w x 4 - 125 w x 4
Power @ 2 Ω: 135 W x 4 - 180 w x 4 - 225 w x 4
Power @ 1 Ω: 190 W x 4 - 265 w x 4 - 325 w x 4