Pump up the volume
In our last edition of “AudioFile,” we discussed how crucial the cartridge — whether it’s a moving magnet or a moving coil — was in retrieving musical information from vinyl records. Let me point out, however, that the musical signal that the cart picks up is so low (thousandths of a volt) that it necessitates a phono stage to bring it up to the volume level of the other music sources you listen to such as CD, SACD, or even DVD audio players.
How a phono stage manages to pump up these minute musical signals from the cartridge is vital: music data could simply be lost or twisted at this stage rather than later on in the signal corridor. Lost musical information can never be recovered; worse, distortions and colorations are augmented several times over.
Most of today’s audio preamplifiers do not have phono inputs because vinyl was deemed to have died out with in the advent of the CD. With the reemergence of analog sound, a few preamp brands (with the exception of Manley Steelhead, Burmester and other reputable audio brands) have come up with an on-board phono stage that is no more than a token move, in my opinion, in order to cash in on the analog renaissance.
Hooking up your analog rig to this token phono inputs immensely diminishes the capacity of your cart to bring out the magic of music from vinyls. Consider this: about 95 percent of bass and 80 percent of mid-range amplifications happen in the phono stage. This is why you shouldn’t trust your beloved audio rig with them. Luckily for us, just as quickly as some have written off vinyl, out-board phono preamp have swiftly sprouted in the market. This out-board or stand-alone phono gadget can be hooked into the line input of your pre-amplifier
I can’t stress this enough: a vinyl-based system can’t live without a properly functioning phono preamp. More than pumping up those minute musical signals, it also reverses or restores the so-called RIAA (Recording Industry Association of America) curve to the music’s original frequency response.
The RIAA represents the recording industry distributors in the US. Its members are composed of record labels and distributors. It was formed in 1952 primarily to manage the RIAA equalization curve, a technical standard of frequency response applied to vinyl records during manufacturing and playback.
RIAA equalization puts pre-emphasis on recording and de-emphasis on playback. A record is cut with the low frequencies reduced and the high frequencies boosted; on playback, the opposite occurs. The result is linear frequency response. The phono preamp makes sure that RIAA re-equalization during playback is strictly executed, a must in faithfully producing the original musical content without coloration or distortion.
There are several brands of phono preamps to choose from in the local market: NAD, EAR, Black Cube, Graham Slee, Lukaschek, among others. You could also ask trustworthy local DIYers to custom-build one for you. Gain as much information about each brand from the Net. You can also read reviews done about these brands. Of course, the best way is to bring one over to your music room for audition.
It’s only in hearing how different brands perform in your system that you can make an informed purchase. If you’re on a budget, you can sift through audio forums for excellent deals on used, but mint-condition, units.
Turntables, tonearms, carts and, yes, phono preamps complete your analog set up. If they match up, they’ll juice out that vinyl magic music lovers around the world so passionately seek.
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For comments or questions, please e-mail me at audioglow@yahoo.com or at vphl@hotmail.com. You can also visit www.wiredstate.com or you can tweet audiofiler at www.twitter.com for quick answers to your audio concerns.
