Both conditions are have been completed. While the first condition tested whether participants could tell the difference between two fully different systems, the second condition tested their ability to determine the difference between a single component: the preamplifier. In this condition, the first system contained the expensive setup from condition one (VPI HRX, Dynavector DRT XV-1s, Kimber KCAG interconnection cables, and a Manley Steelhead preamplifier) and the second system contained the same setup except other than the preamplifier, which was replaced with the Pass Labs Xono (originally from the moderately priced setup in condition one).

The second condition was run during 2 weeks: May 9-13, and May 23-27. The listening room (CIRMMT's Critical Listening Room) was setup in the same configuration as the first condition (please see previous post).

At present we are awaiting the results to be analyzed. These will be done within the next couple weeks. Below is a brief summary of the experiment.

This study investigates whether expert listeners can hear differences between PPS using closely matched components—at different price ranges—and if so, how they describe these differences and which PPS they prefer. Our motivation is as follows: if there is no audible difference between two systems in an optimal listening environment, then the discrepancy in price may not be justified for archival purposes.
For our study, we define a PPS as a system used in the playback of phonograph records. Each system is comprised of the following components: a cartridge, a turntable, a preamplifier, and two pairs of interconnection cables. All components are manufactured by well-known, reputable companies. The cost of the high-end system was approximately five times that of the mid-range system. The high-end system’s components were chosen based on component cost and by industry recommendations for optimal component choices, given the pool of equipment available to the study. The mid-range system components were selected through an iterative process of informal testing and component substitution aimed at minimizing audible differences between the two systems. Both systems were assembled and calibrated with reference to a well-reputed guide.

As the source medium used in this study is analog, the produced audio signal varies subtly with every take. For this reason, we selected unplayed phonographs as audio sources. However, even new phonographs are subject to dust and static. The phonographs were therefore vacuum-cleaned prior to each take to assure that the presence of dust was minimized and that the remaining dust was randomly dispersed across the record. Phonographs were recorded using a high-end analog-to-digital converter at 24-bit 96-kHz. Each phonograph was recorded twice on each system in a counterbalanced fashion, resulting in four Audio Interchange File Format (.aiff) files for each excerpt. Five musical phrases of 5 to 8 seconds representing standard musical genres (e.g., jazz, classical, rock) were selected; only phrases that were free from audible artifacts of the recording process (e.g., pops, hiss) were used.

Participants were professional sound engineers and audiophiles who reported listening to vinyl for several hours per week. Both listening tests were performed in an ITU standard room using an AB preference task. In each trial, participants heard two recordings of the same phonograph record, recorded on either the same or different systems, and selected the one they liked best. Participants also describe the perceived differences between the two systems in a post-questionnaire.

Each test was comprised of a training block and 4 experimental blocks of 12 trials each; each block contained recordings from a different phonograph record. To nullify order effects, block order was counterbalanced between participants, and trial order within each block was randomized. Differences in output levels across each system were mitigated by adjusting the gain of the mid-range system’s files using an audio editing software.

The first test investigated experts’ ability to discriminate between the high-end and mid-range systems described above with eleven expert listeners. A second test investigated the effect of varying a single component—the preamplifier—between two otherwise identical PPS. All other components were derived from the high-end system of the first test. The cost of the preamplifier in the more expensive system is approximately three-times that of the other preamplifier. Fourteen expert listeners participated in the second test. All results are provided using 2-tailed cumulative binomial tests.