It's not just the top and bottom, it also is the middle. All acoustical
recordings have horn resonances, and if you use a parametric equalizer
you boost the midband and sweep it up and down till you really hear a
BIG boost -- and then you cut it a at that frequency a few dBs below the
rest to even out that resonance. With a graphic eq you can smooth out
several resonances. Tom Owen was the first to really address that issue
when he introduced the Owl I. The Urei Multifilter is also useful. You
will also find resonant peaks in electrical recordings. I am surprised
that this has not been discussed much here.
Mike Biel [log in to unmask]
On 3/6/2011 7:04 AM, Tom Fine wrote:
> One man's opinions/experiences ...
> You need to use your ears. These are guidelines, not rules. I've never
> liked the sound of anything with flat rolloff, it's always too noisy.
> The early stuff has very limited high-frequency content so you can
> rolloff quite a bit without effecting any recorded sound that made it
> into the shellac pressing you are playing. It gets more interesting in
> the electronic era because there comes a point -- different times for
> different record companies, when there actually is important audible
> content in the "treble" range and it's loudness is effected by both
> turnover and rolloff since you are both moving and bending the curve.
> Start with the "common wisdom" and then season to taste. There are
> many, many listings online of different curves recommended for
> different record companies in different eras. I have found the "common
> wisdom" on RCA, USA Decca, Capitol and Mercury to be my preferred
> settings in most cases. The "common wisdom" on pre-electric anything,
> Columbia, Okeh, Vocalion and British HMV does not suit my ears, I
> usually tweak those to sound best to the content (most content, least
> noise, to over-simplify it). Almost uniformly, my experience is that
> the later-era the 78, the easier it is to pull the content out of the
> grooves. Early stuff is a challenge and there's only so much content
> Also note that not all recordings were made to allegedly "standard"
> curves, not all recordings sound good to begin with and not all
> pressings are uniformly good. So, use the options of variable EQ to
> bring out maximum audibility and clarity. Basically, you'll find a
> pair of settings that sounds "best" for every record. Sometimes it
> sounds clearly "best" compared to all other settings (instruments
> sound natural, balance of the ensemble sounds right, background noise
> does not distract), sometimes it sounds "least bad" because the
> recording was bad or the pressing is bad, etc. If your preamp has
> high-pass and low-pass filters, also experiment with them. You can
> further bring out the program content and reduce the background noise
> I also try to go for the best sound quality at each stage of analog
> playback so you can then use a minimal number of stages. If I can get
> a "best" sound right at the phono preamp, then I don't need to insert
> EQ into the signal chain. In the case of 78's, if I can play it back
> crisp, clear and relatively quiet, then I don't need to mess with DSP
> noise reduction or EQ in the computer. Also, using the combination of
> turnover and rolloff to both bend and move the curve sometimes
> produces much better-sounding results than blind adherence to "common
> wisdom" with after-the-fact reliance on heavy-handed EQ to "quiet
> things down." This method is widely used on low-cost reissues of 78's,
> they are usually chopped off somewhere around 10k and "NR'd" to death
> so all the low-level content is removed and it's like listening to a
> low-grade AM broadcast.
> Always rely on your own ears and taste rather than machines.
> Documentation and "common wisdom" is the place to start, not the place
> to end.
> -- Tom Fine
> ----- Original Message ----- From: "Jan Myren" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, March 06, 2011 5:33 AM
> Subject: [ARSCLIST] Turnover and rolloff curves for correct playback
> of 78 rpm records!
>> I am about to learn to find the general correct turnover and rolloff
>> for US and European 78 rpm records.
>> So far I have learned:
>> US 78 rpm records:
>> Pre. 1938: turnover 500 (RIIA), rolloff FLAT
>> After 1938: turnover 500 (RIIA), rolloff -5
>> European 78 rpm records:
>> Pre 1938: turnover 300, rolloff FLAT
>> After 1938, turnover 300, rolloff -5
>> Can anybody share their experiences within this matter, please?
>> All the best
>> Jan Myren