Effect of variable amounts of dynamic compression???
Puzzled...
Just say, you have noticed a difference in SPL (sound pressure levels) between different albums/tracks when the volume level of your preamp is at the same gain setting, sometimes very large SPL differences. This is consistent and repeatable.
Then, say you notice that many times, by and large, more often than not, etc., that you perceive that the sound quality of titles with a higher recording level (requiring a much lower gain setting on the preamp for a given SPL) tend to sound significantly less enjoyable to you than those that require higher volume level settings on the preamp for the exact same SPL.
Next, you realize that the poorer sounding titles require volume settings significantly below the preamp manufacturer’s specified "Unity Gain" setting level and the better sounding recordings require settings at or above that Unity Gain setting for the same SPL.
Why?
Remember, you set SPL levels for all titles the same and your observations are not always true for every title, just much of the time, yet consistent and repeatable for a given title.
Then, say you notice that many times, by and large, more often than not, etc., that you perceive that the sound quality of titles with a higher recording level (requiring a much lower gain setting on the preamp for a given SPL) tend to sound significantly less enjoyable to you than those that require higher volume level settings on the preamp for the exact same SPL.
Next, you realize that the poorer sounding titles require volume settings significantly below the preamp manufacturer’s specified "Unity Gain" setting level and the better sounding recordings require settings at or above that Unity Gain setting for the same SPL.
Why?
Remember, you set SPL levels for all titles the same and your observations are not always true for every title, just much of the time, yet consistent and repeatable for a given title.
16 responses Add your response
@dlcockrum It’s Dynamic Range Compression used in the recording process. Most of my Sheffield Lab Direct to Disc are a lot lower compared to most others. This should explain it! https://en.wikipedia.org/wiki/Dynamic_range_compression |
Thanks for the helpful replies swampwalker, Eric, yogiboy, and Geoff. Thought I was in the know about dynamic range compression but I failed to associate it directly with relative gain of the playback system. Was beginning to think that maybe my preamp was better at signal amplification than at attenuation or similar causes. The "effect" I described in the OP was brought into sharp contrast when I recently moved to an ultra-revealing/detailed DAC in my computer audio chain. I always noticed that there was a "price to pay" for superior resolution related to the limitations of recording/mastering technology of our media and this is an extreme example of that. I think maybe this is a part of the magic of the better analog sources, ie my TT rig. The waveform that they generate provides amazing detail yet does not emphasize the effect of compression on sound quality quite as profoundly as digital IME. The offset is that the sound quality of great recordings benefits at all volume levels and I find myself listening at lower volume levels overall and still retain the listener involvement quotient of higher volume with lower-resolution sources. Dave |
that only tells that more complex equipment with adjustability wins on sound performance over the unadjustable units when playing imperfect recordings. adjustability of gain, tone controls, filters, adjustability of feedback -- it's often not found in today's home audio units, because it's complex to implement and takes away a big chunk of profit. |
I had such versatile preamp. Mcormack Micro Line Drive . passive, active with gain settings. I kept cover open in order to play some of the records to swap jumpers LOL. It was inconvenient, but the most transparent preamp I've ever had or heard in any mode: passive or active with any gain settings: Unity, 6dB and 12dB and passive. I rarely used passive, but mostly used unity. |
McCormack is still around, but this model is hard to come by. check out that prior auction to have an idea...http://http//www.ebay.com/itm/MCCORMACK-MICRO-LINE-DRIVE-PREAMP-WITH-THORENS-PHONO-PREAMP-/232415442020?hash=item361d0a3464:g:lVYAAOSwuq9ZZrkL |
This may help as a reference to view DRC rates for various albums & CDs, http://dr.loudness-war.info/ |