33 vs 45 speed quality

On the outer grooves of a 33 there is no real advantage to the higher speed, although 45s might sound better for other reasons simply because they are produced for the audiophile market. However, as the pickup moves to the inner grooves the speed of the vinyl passing the stylus becomes very marginal for sonic quality. Cutting the record at 45 rpm preserves sound quality at the inner grooves (although using 33 rpm and just not recording anything on the inner part of the disc would yield the same result and playing time). 45 rpm was invented for the singles, which were all inner grooves.

Zaikesman...Interesting ideas about effect on surface noise. I'm not so sure about the "dynamic slam". We are agreement about remastering for the audiophile market.

Have you ever listened to a phono signal without RIAA equalization? (You do this with a microphone preamp). The bass is so severely attenuated in the signal that it is a wonder that anything useful can be derived from it. I think that some enterprising audiophile outfit should toss the RIAA curve and 33 rpm speed in the trash can, and start over with the understanding that appropriate (special) playback equipment is necessary to use the resulting vinyl product. A niche market.

The DBX vinyl records of several decades ago were like this (required a decoder box) and the results were excellent. The DBX system addressed every troublesome aspect of vinyl playback. Too bad that the system came out just when CDs were introduced. Were it not for CDs, we would be using the DBX system today...IMHO.

Zaikesman...The DBX compression/expansion process was not a problem because DBX designed both ends. Master tapes for most LPs are made using DBX processing which is considered to be better than Dolby, the other method. So if there is any problem you already have it.

The most obvious advantage of the DBX processing is the elimination of audible surface noise. But there is more. The groove modulation is always near optimum for cartridge performance, which greatly reduces distortion, and mistracking. More playing time can be put on a 12" disc. There are some other advantages which I can't remember off the top of my head.

Zaikesman...My view about DBX records is biased, in that I actually have some. (But the decoder died about ten years ago and I have never fixed it). It is too bad that I can't suggest how you might have this experience. The audio quality is superb, but the catalog was tiny, with few well known artists. Although modern high end cartridges are "capable of tracking..." distortion (short of outright mistracking)is very much a function of modulation amplitude, and limiting dynamic range (of the groove) is very desirable. The electronic reexpansion process may not be perfect, but has much less distortion that that which would occur if the cartridge had to track the uncompressed groove.

Master tapes made before the days of Dolby and DBX were still compressed...manually by the recording engineer (called "Gain Riding"). This avoids peak overload while allowing higher recording level for quiet passages so as to minimize tape hiss. But with this manual compression the results varied according to the engineer doing the recording, and so could not be effectively reversed on playback so as to restore the original dynamic range (although there were expander electronics that tried). By precise control of both the compression and expansion algorithms DBX and Dolby can do the job without audible problems (eg: "pumping").

Zaikesman...You have come up with so many ways that compression is used that, contrary to what we often see stated, it must be a good thing!

I don't think that Peak Limiting is arcane...it's just a gain reduction that is applied only when the signal exceeds some high value. So almost all of the time it does nothing, and, if the setup is correct, it only activates when your amplifier was about to clip. I think that even audiophiles can endorse this.

Tbg...Returning to the topic...no doubt that your 45 rpm issues sound better than 33 rpm versions. However, except for the inner groove problem that I mentioned, I think that the improvement results from other aspects of the production rather than the speed per se.

Tbg...You need a vintage record changer :-)