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Accession MM + Elevator EXP + HOMC

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Graham Slee View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 10:01am
There's a difference between idiots and those who want to learn. The idiot just throws non-sensical arguments which grow more ridiculous, and eventually goes somewhere else (sometimes hurling abusive language on the way out - I've worked behind a counter).

You are wanting to learn and have shown that by trying to work stuff out. That's a good start, so please refrain from calling yourself an idiot.

The community here tries to help out the best way its members can, and each of us giving you suggestions has some knowledge, often quite advanced in the things they're most interested in.

In my case, being an old analogue designer, I have limited practical experience in digitising, so I'll not comment about the techniques you're using compared to those being suggested.

Where I can help is in sharing matching values of analogue signals, and it appears to me that the ADC you have requires about 1.2V to output 0dBFS digital level.

0dBFS is the maximum possible output - the limit of transients above which those transients would flat top (be clipped).

So now we have to know the "height" of transients compared with "average maximum" from the record. IEC 61938 says +17dB (7x), and the actual limit of overload of an LP microgroove record is +14dB (5x).

I think the IEC errs a little on the side of caution (or might be thinking about 45 rpm singles), so +14dB seems more practical.

The output voltage of a cartridge is stated at its maximum for a particular groove velocity. That velocity DOES NOT include transients!

Therefore, the voltage required is 14dB below 0dBFS. So if the cartridge outputs 2mV, and the phono preamp outputs 240mV, then +14dB is 5 times 240mV, which is 1.2V.

1.2V is +4dB, and so with the gain control on the ADC at maximum (for that input range) it looks like that's correct for making a clip-free recording.

I'm sure others on here might be able to point out if I've made any errors in my assumptions.
Not simple enough for Google-Bot to understand...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote patientot Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 3:12pm
Originally posted by cameroncollet cameroncollet wrote:

@patientot no worries I can be pretty idiotic. One thing I neglected to mention is that I'm recording directly to DSD. While I do cut a copy of those to PCM (24/192 or whatever), the DSD files aren't modifiable.

The other problem with recording to DSD is that any digital modification to the stream is turned off in the ADC when recording. Which means the sensitivity isn't -2 dBu, it's +4 dBu (losing 6dB of digital gain). So minimum sensitivity isn't 616 mV, it's somewhere around ~1228 mV. Even if we've confirmed I'm an idiot at least I learned a bit 😂

Honestly the Elevator was already on my mind before I ran into this issue. At some point I wanted to move to LOMC, this just moved it up. Also with the Hana SH/SL the carts are the same cost. Worst case I'm losing a restocking fee on the cartridge, and gaining the flexibility of LOMC on a really good MM phono.

Edit: I did also search around for the threads on interference and the Elevator. I've made my own cables using mogami wire and bought decent cables at times as well. The Rega Planar 8 doesn't have any exposed wires, the RB880 tonearm seems to do pretty well, minus fine adjustment options. Hopefully, worst case, I'll end up with a new set of cables from here if needed 😅



Aaaah, DSD would explain why you don't want to modify the files. FWIW there is little practical reason to record needledrops in DSD. Sony, the company that helped invent it and originally envisioned it as a format for archiving master tapes digitally, has largely abandoned those plans and did so years ago.

The reason was that mastering engineer digital audio workstations can't really edit DSD easily either. They would have to convert the files to PCM first for editing, and then convert it back. So much for the superiority of DSD. All those SACDs made from master tapes have been converted back and forth several times!

The other thing is DSD will generate loads of high frequency noise (60KHz +) that's not part of your original record you're trying to record. The same thing can happen with high PCM as well but it can be a very obvious problem with DSD.

You may not want to hear this either, but vinyl records are limited in dynamic range and S/N ratio, so recording at super high PCM bit rates or DSD bit rates is rather pointless as well.

If it were me I would simply record in PCM, either at 16/44 or at 24/44. The latter would make sense if your audio editor program works off 24 bit, which most do.

RE: your cables, I would visit the recent thread on cable construction Graham made.


There is a diagram showing different methods of cable construction.
Reflex M + PSU-1 used with AT150-40ML, AT VM95ML, Stanton 680mkII + Ogura, and Shure M35X cartridges.
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cameroncollet View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cameroncollet Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 5:08pm
Yeah I'm aware of most of the issues with DSD. I think what I like about it overall is just what it's original purpose was, archiving with the most bits possible shoved into a file. I feel like once I have that I can turn it into whatever I want from there, and not worry about losing anything between.

I got into this while archiving my mom's old vinyl from the 60's on, and eventually enjoyed it so much I've started to build my own collection from various pre-digital recordings/one-steps/etc, and fallen down the rabbit-hole of headphones, amplifiers, then speakers, and now turntables and phono's.

There's a nice space in the DSD recordings for me, like they have a bit more air to breathe, but for space purposes I usually only listen to those on a DAP and at my desk. For portability I drop a version to FLAC 24/192 and maybe do a little click correction for the worst ones. @Graham I'll stop calling it idiocy and start calling it stubbornness 😂

Funnily enough I started with a Project Recordmaster Hi-Res table that did all this in one. Most of these purchases have been trying to replicate the same recording functionality, but gain control over the pieces between the record and recording software. Same way I learned how to build computers 😂 PEBKAC
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Chris Firth Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 6:28pm
Originally posted by cameroncollet cameroncollet wrote:

PEBKAC
I've not heard that one for a good while LOL

On the issue of levels - the ECM label tends to err very much on the side of safety and non clipping with many of their CD releases.
One that I have - Making Music, by Zakir Hussain (and a few other notable musicians) was that low I ended up doing a visual check on the track waveforms and boosted the lot by +7dB.
It's still under the 0dB threshold, but there's a much higher signal level as a starting point, which is beneficial in my opinion.

On the DSD front, commercial releases are more often than not dealt with in the PCM world until the final DSD step.
So tracked, mixed and mastered as PCM, with a DSD transfer straight from the analogue output of the PCM DAW into a DSD converter.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 7:00pm
Oh, I'm sure we all have a stubborn streak...

Mine is lecturing about vinyl, that it has a maximum dynamic range of 72dB which is a bit-depth of 12 bits and a 48k sampling frequency is more than adequate.

The great thing about analogue is that it's not constrained by bit-depth, and so its minus 58dB noise floor is simply "low-cloud" which allows a glimpse a little deeper (but not by much).

Likewise, it can peak at +14dB on high dynamic range recordings, and you need that extra 3dB insisted upon by IEC if you play hot 12" singles.

Even so, CD quality bit-depth gives 96dB dynamic range which is still in excess of what the best vinyl is capable of. Convincing oneself that it needs more than CD quality is a bit sad in my opinion, probably because of "comforting" marketing jargon.

But, in our listening space we're only going to get the benefit of say 10 bits due to ambient noise, and the ear pain if we play our music too loud.

That's just my take on common sense. Smile
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cameroncollet Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 7:54pm
I've read it before, and I'll probably read it again later. You are very, very likely correct, and the only reason I don't say it with certainty is because I don't know enough to confirm it.

I think I'm just having fun with it 🤷‍♂️ keeps me occupied and a little more sane with everything that's going on.

Love how much you're involved with the community here. Wish everyone the best 😊

I'll be back if I blow something up (figuratively 😅).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Fatmangolf Quote  Post ReplyReply Direct Link To This Post Posted: 19 May 2022 at 8:31pm
If you like it keep enjoying it. Digitising vinyl records is always a leap of faith but satisfying.
Jon

Open mind and ears whilst owning GSP Genera, Accession M, Accession MC, Elevator EXP, Solo ULDE, Proprius amps, Cusat50 cables, Lautus digital cable, Spatia cables and links, and a Majestic DAC.
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