A savvy member over at another forum/thread I’m in breadboarded a no-RIAA preamp with gain to run into a MOTU ADC. I can reach out to him if useful. Likely easy to modify gain or HF rolloff limit. https://forums.stevehoffman.tv/thre...ing-best-needledrop-practices.250442/page-213Now come the practical difficulties. I need to make sure @BMRR(VE) has recording capability without RIAA, and that if so the line input has wide enough bandwidth. I suppose it would not make sense for a system with 96kHz sampling rate to not have the full 48kHz bandwidth, less IRF.
I'm not sure I am the best to comment here since the recording I do, and I have done extensive recording, is to convert vinyl records to digital files. I typically record at 96/24 but I can record 192kHz/24bit. That is a large file, trust its only a short segment.
Does “Flat MM” suggest that no RIAA comp was applied at digital recording but digitally compensated for during the DSP measurement?As was briefly discussed over at Vinyl Engine here is a Shure ML140HE with some wear on it. The exact amount of wear--and how much life is left--is impossible to say at this resolution, but the important thing is that we can certainly say that it is present. Luckily I bought this stylus for measurement purposes for only $30.
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It may be the case that the possible uneven wear from poor azimuth adjustment may be the cause of the 2nd harmonic of the right channel to be a bit higher than the left channel. That being said, the measurement looks pretty good (actually really good) in the end, with the only below average part being distortion above 10kHz.
While not exactly apples to apples, here is a ML120HE in good condition:
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It is expected that the ML140HE is the "better" cartridge. Its distortion above 10k now certainly stands out and we think that this is where the wear is "showing up." This fits with the general industry consensus about the matter.
But I had previously said that I was noticing wear between 3-10kHz. But that was with regular elliptical styli. Here we have a hyper-elliptical. So the diamond shape may dictate where to "look" and things may be more complicated that what general knowledge says. This makes sense but it is good to see and good to look out for.
Yes, sort of. There is no RIAA compensation but that works well here because you aren't supposed to apply it to properly use the test record in order to have accurate results (remove the phono stage). I do apply perfect, digital RIAA when digitizing records. Best of both worlds. For casual listening I use phono stages.Does “Flat MM” suggest that no RIAA comp was applied at digital recording but digitally compensated for during the DSP measurement?
To provide additional data on the sonic impact of record wear, two records will be recorded by @Tetonbound before the experiment using a Tascam DA-3000 pro-level recorder at 96kHz and 24 bit. These recordings will be done on near mint records to establish a baseline of sonic quality of selected records.
What plugin do you use for fully accurate digital RIAA? I experimented beck in the 90’s with the Waves RIAA EQ plugin preset but was not happy with the results. Just went with a fully balanced RIAA solid state pre made by Audio Research (SP2, i think).Yes, sort of. There is no RIAA compensation but that works well here because you aren't supposed to apply it to properly use the test record in order to have accurate results (remove the phono stage). I do apply perfect, digital RIAA when digitizing records. Best of both worlds. For casual listening I use phono stages.
I use this, Wayne Kirkwood Flat MM Phono Preamplifier. It is wonderful. Simply adds gain and nothing else.
No real need for several reasons. First, there are plenty of examples on the measurement script thread and its not so bad once you establish how a record performs. And most importantly, there is no real benefit because of how the experiment is set up. As they will be removing the cartridge to image it, the concern should be on making sure it is comparably set-up after each step. That's the concern that was mentioned here and why the experiment is only a first step. To properly measure it over the long run, you will need to minimize variables, which also means leaving the cartridge alone. Still, the first run should show interesting results.This should be done several times for each, to get a range for inherent playback variance.