Bellari VP549 Phono Preamp with RIAA Equalization Curve The Bellari VP549 has excellent true sound resolution, no frequencies are omitted. Its tone center is right in the middle of the music. It performs very well on the extremes and never loses its solid performance when things get loud. It never gives you the impression that it has artificially fluffed up the bass or over emphasized the treble. It is well balanced and bold, yet has a very surprising attack that will take your rig to the next level.
The RIAA equalization curve was intended to operate as the global industry standard for records since 1954. However, it is almost impossible to say when the change actually took place. RIAA equalization is a form of pre-emphasis on recording and de-emphasis on playback. A recording is made with the low frequencies reduced and the high frequencies boosted, and on playback the opposite occurs. The net result is a flat frequency response, but with attenuation of high frequency noise such as hiss and clicks that arise from the recording medium. Reducing the low frequencies also limits the excursions the cutter needs to make when cutting a groove. Groove width is thus reduced, allowing more grooves to fit into a given surface area, permitting longer recording times. This also reduces physical stresses on the stylus which might otherwise cause distortion or groove damage during playback.
A potential drawback of the system is that rumble from the playback turntable's drive mechanism is amplified by the low frequency boost that occurs on playback. Players must therefore be designed to limit rumble, more so than if RIAA equalization did not occur. Using a rumble filter to filter out the subsonic frequencies many help mitigate the noise from the turntable. The rumble filter, AKA "subsonic filter" cuts very low frequencies (below 20 Hz). The purpose of a filter like this is to get rid of annoying frequencies that disrupt the turntable's sound quality. A good rumble/subsonic filter should be inaudible, meaning you cannot hear when it is on or off in the program material you are listening to. What it will do is help with excessive very low frequency interruptions from the turntable to the preamp
Specifications:
• IO connectors: RCA, 1/8" TRS
• Input impedance: 47 kohms
• Output impedance: 32 ohms headphone, 470 ohms RCA
• Frequency response: 3-36,000 Hz
• EQ: RIAA ±1 dB, 14-23,000 Hz
• Rumble filter: 20 Hz
• THD: 0.005% @ 1 kHz
• SNR: >94 dB unweighted
• Power requirements: 15 VDC
• Dimensions: 5.5" W x 3.5" D x 1.25" H
