One man's opinions, experiences, YMMV, etc. ...
Steve is right that a graphic EQ is helpful, and I also think a preamp with adjustable turnover and rolloff is very necessary. Dial in what sounds best for casual listening, dial in what's truest to the source for archival tranfers. On later-era 78's, there can be musical content at 12K and even higher. For acoustic era, there is nothing even at 8K in almost all cases. The thing is, not graphic EQ just lops off at the stated frequency, they all have a curve that bends up or down over a bunch more frequencies below and above the target frequency, so tune by ear.
A box of shellacs picked up at a 2nd hand store are just not going to sound like a modern reissue CD made from metal parts. You will never achieve the low noise level and low distortion level of primary source material. Manufactured shellacs vary in quality from quite amazingly clear to fuzzy noise-hash messes. It depends on the manufacturer and manufacture date and how the thing has been stored these many decades.
Of course, cleaning a shellac before playing is key. Deep cleaning the groove eliminates many ticks and pops and can reduce background hash. You can use a vacuum/scrub machine (use the appropriate cleaning fluid and change the brush and vacuum pad before doing LPs), or a simple soft sponge and Ivory dish soap works. Rinse thoroughly and pat dry. And of course wet the record before sponge-ing it. Those blue shammy clothes sold at record-sleeve online stores are a great finish-dry cloth. Store the cleaned records in new sleeves; as kewl as those ancient brown-wrinkled sleeves are, they are not appropriate for storage after decades of dust and casual storage.
Steve is also right about bass content. It's usually a compromise between rumble reduction and legitimate bass content, tune to ear's preferences.
As for dbx (Jan was obviously asking about the companders like 3BX and 2BX, not the closed-loop NR system), and the Phase Linear 1000 for that matter, they can help if used very carefully, especially on non-music content like transcriptions. Very conservative, very careful, they can reduce background hash a little bit. But, any modern digital NR will do a better job if used properly.
Again, one man's opinions, experiences, YMMV, etc.
-- Tom Fine
----- Original Message ----- From: "Steven C. Barr" <stevenc@xxxxxxxxxxxxxx>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Friday, May 22, 2009 10:55 PM
Subject: Re: [ARSCLIST] DBX for playback of 78s
----- Original Message ----- From: "John Eberle" <JEb45ACP@xxxxxxx>Here is my take on this : DBX Noise reduction is an encode in recording and decode in playback system designed to reduce tape noise in professional recording studios . There was an attempt by DBX to interest the record industry in a version designed to be used in the mastering of 45s and lps and the decode unit was to be incorporated into the preamp or the playback system . The company I was working for at the time , Nashville Record Productions in Music City USA was given an onsite demo of this system and it was considered by many in the industry for adoption as it was quite effective. The big drawback to the DBX record system and the reason for its' lack of acceptance was that the DBX encoded record was most unpleasant to listen to on a playback system that did not have the DBX decoder ; making compatibility in the market place a big problem
I always found that the most useful tool for listening to 78rpm phonorecords was a standard (and cheaply available these days) 10-band equalizer. Obviously, more advanced eq's (if one can afford them?!) would be of better use!
At any rate, 78rpm phonorecords of the 1889-195? era basically had a "bandwidth" (frequency response) of around 50-6000 kHz. THAT is what is on the original recording (although it MIGHT be possible to recreate "implied" notes via a computer?!).
I always set my eq to chop the upper octave (no recorded content there!) and the lower couple of octaves (three for acoustic originals!) for the same reason!
One caveat! Apparently, the bass response of early-electrical-era 78's was MUCH lower than one might expect; I have MANY pipe-organ recordings (Jesse Crawford et al) mage in that era which exhibit AMAZING low-end content...!!
Steven C. Barr