33 1/3 vs 45 rpm

IME, > 90% of the time, 45 rpm sounds better. The grooves are spread wider allowing for greater cutter (the lacquer) dynamic range which then translates to the vinyl, imo. There is obviously less inner groove distortion as the grooves generally stop two thirds or less into the record side (better tracking).

Plain physics tell me that 45rpm should be better than 33 1/3. At 45, the outer grooves travel at about 27 inches per second. At 33, it's about 20ips. On the inner grooves it's 9.4ips vs 7ips. You not only get better dynamic range, you should better frequency range as well. You can calculate peak to peak distance at 20kHz on the waveform imprinted in the grooves.

However, I find that 45rpm generally has higher vinyl noise energy, and I prefer listening to 33 1/3. Now, the problem is that there is no way to compare apples to apples as even within the same re-issue, the 33 rpm is mastered different from the 45 rpm.

There are a bunch of new LPs that distribute the music over 4 sides at 33 rpm with grooves that look wider than on some 45rpm albums I have. What I have found is that I loved every single one of those albums - Girl, Black Light Syndrome, Two Men With The Blues. May be it's the music. May be it's because my t/t set-up skills work only at 33rpm.

45

sombunya said:

This is in regards to new, 12" vinyl platters. I recently acquired an album with two discs that play about 4-5 minutes per side.

Is there any gain in fidelity? I've seen some 12" singles have or had deeper grooves that I would presume gave more "sound pressure" or in the magnetic tape world would be called dynamic range (I think). Doesn't seem to be the case here though.

Anyway, after years of MSFL, RCA "Red Seal" etc., I'm wondering if there's any advantage to mastering a 12" vinyl at 45 rpm other than shortening the time the program plays on each side?

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If I can find a piece of music I like at 45 rpm 12 inch disc I will pay the extra and buy it. I feel it sounds better it may be more care is taken with a 45 mastering as fussy people buy them. It may be because it is at a higher speed and all the reasons above or a bit of both. I think it is worth it to have something you really like at 45 rpm just my 2 cents worth.

On my 33.33 RPM Sheffield Drum Record, the 7 min song takes up almost the entire side. It is an extremely dynamic recording, direct to disk, and I'm not even sure that the material would even fit on one side if pressed at 45 RPM. Sonics are incredible at 33.33.

In general, my 45s sound better than my 33s of the same recordings. I find the low frequency information is better on the 45s.