LP transcription questions

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jrmintz

Well-known member
Joined
Jun 4, 2004
Messages
998
Location
NY
Hi,

At some point I will have to do some high-quality LP transcriptions into Pro Tools. My question is mostly this: do I need to have an RIAA curve preamp or can I run my turntable output directly into a microphone preamp? I'll be remastering for CD so absolutely accurate EQ is not crucial. I can fix it later, or at least I assume I can. Is there some reason to use application-specific phono preamps that I don't know about?

Also, anyone have recommendations for new cartridges that are good quality and somewhat reasonably priced? I have an older Shure V15 and there doesn't seem to be a new version of it.

Thanks,
 
[quote author="jrmintz"]Hi,

At some point I will have to do some high-quality LP transcriptions into Pro Tools. My question is mostly this: do I need to have an RIAA curve preamp or can I run my turntable output directly into a microphone preamp? [/quote]
I'm not sure if I understand your requirements. High-quality, but not-totally accurate EQ would be OK?

I guess you could do worse than using a decent 'hi-fi'-amp with a phono input and route the tape-deck-send (amplified to 'line-level' of around 150..200mV & 'RIAA-ed') to your DAW.

Or build one, or instance the simply but nice LM4562 RIAA application circuit, mabe you have some samples around already.

I'm not aware of 'post-filtering RIAA-corrections' inside a DAW but since the 'original thing' could be simple enough I would try anything without, it could & will very well work but requires additional checking etc.

If you're after the highest quality then without doubt various brands will gladly sell you a standalone phono-pre.

IIRIC there was also a recent RIAA-thread here. One of the things discussed was that the cartridge wants to see a specific loading for 'linear freq response'. Using a mic-input will require not only the RIAA-ing but also additional compensation i expect.


Regards,

Peter
 
This is something I do on a regular basis. As Peter hints, you'll need an RIAA EQ. Not only that, but your average MM cart will need to see 47K input impedance with around 100pF capacitance (some preamps offer a selection of 100pF / 200pF, as well as different loading options).

A MM cart will need 35dB gain to bring it to line-level, and an MC needs 60dB gain. I tend to prefer transformers to interface MC carts as you get the gain "for free" (I've yet to hear an active MC stage that's really impressed me, or been particularly quiet...)

As far as cart recommendations go... What's your budget and criteria for quality? Sadly, the V15's replacement (V15XMR) was discontinued a couple of years back. IIRC, you can still find the styli, so a secondhand unit probably isn't a bad move (it's quite a pricey cart btw).

You can't really go too wrong with Ortofon in my book. The 540 is pretty good for the price: http://www.needledoctor.com/Ortofon-540-MkII

There's also the venerable Denon DL103: http://www.needledoctor.com/Denon-DL103?sc=2&category=369

The nearest thing you'll find to a current V15 would be the MX97E (some people claim it's better value than the V15): http://www.needledoctor.com/Shure-M97XE?sc=2&category=380

If your family have access to the turntable, the OM range is useful as you can fit a tough DJ stylus for non-critical work, and replace it with an OM30 or OM40 stylus for transcription.


Justin

BTW - If you need to find a dealer in the NY area that's reasonably priced and won't feed you any audiophile BS, Kevin at KAB is highly recommended: http://www.kabusa.com/frameset.htm?/index.htm
 
Not sure what his fave cartridge is right now but my friend Don likes various turntables and pivoted arms. He used to sell the Airtangent linear arm but it has ceased production, and he says he can't recommend any of the other ones.

He did say that, except for some tracking servo bandwidth limitations that show up for HF material on the inner grooves of some LPs, he really thinks the latest version of the laser player is first-rate: http://www.elpj.com/

Don's current setup: "The best buy in high-end turntables is the Goldmund Studio with T-3 tonearm. This is what I own. It sounds awesome and is reliable. They can be bought used between $2k - 4k depending on condition."

I'll ask him what the cartridge is.
 
Probably not high quality, but I saw this at Radio Shack the other day and thought it was a pretty straightforward solution. Catalog #: 42-7012 $70, comes with the cart and the preamp is built-in.

For high quality carts, I'd recommend anything by Grado.

HTH!
Charlie
 
Thanks guys. :thumb:

I know the idea of a high quality transcription without the appropriate EQ sounds muddled. I'm muddled. :green: I really meant that a clean and quiet transfer is more important to me than an absolutely accurate one because I'm going to have to mess with EQ anyway. Brad, I'm in no danger of spending several thousand dollars on a turntable and cartridge. Several hundred (and not many several) is what I had in mind. The WAF (wife acceptance factor) is low at the moment.

:sam:
 
A microphone preamp definitely won't work. They have a typical input impedance of 1.5-3k, and a moving-iron or moving-magnet cartridge (like Shures, Grados, etc.) needs to see 47k. Most moving-magnet cartridges care also about loading capacitance; the Grados are much less sensitive to loading C than their competitors. Tradeoff: lousy shielding, so they don't work on some turntables with synchronous motors. They'll work with Thorenses, though, if you can find one.

A hi-fi receiver actually may not be such a bad deal. Otherwise, look for a decent-quality RIAA preamp -- Jim Hagerman sells a more-than-good one on a PC board which you could put into a box easily enough. Don't bother with the integrated turntable-with-preamp units, or worse yet turntable-with-preamp-and-digital-out. The turntable sections are horrible.

Peace,
Paul
 
[quote author="jrmintz"]Thanks guys. :thumb:

I know the idea of a high quality transcription without the appropriate EQ sounds muddled. I'm muddled. :green: I really meant that a clean and quiet transfer is more important to me than an absolutely accurate one because I'm going to have to mess with EQ anyway. Brad, I'm in no danger of spending several thousand dollars on a turntable and cartridge. Several hundred (and not many several) is what I had in mind. The WAF (wife acceptance factor) is low at the moment.

:sam:[/quote]

The RIAA eq is more than you can easily "fix in the mix". There is some 40 dB change between 20 Hz and 20kHz so it's a good idea to incorporate it in the first gain stage.

You can roll a decent pre with one of several modern hi performance opamps and a few bits of eq in the feedback network. Lots of published circuits out there.

JR
 
Thanks everyone. I looked at the Hagerman preamp, which looks nice - there's also a Marchand kit for a tube preamp that looks cool and not excessively expensive. The job won't be happening for a month or so, so I have some time to think it over. My turntable is a Harman/Kardon T20 from the mid Eighties. It got good reviews in its day - does anyone have experience with them?
 
[quote author="jrmintz"]Thanks everyone. I looked at the Hagerman preamp, which looks nice - there's also a Marchand kit for a tube preamp that looks cool and not excessively expensive. The job won't be happening for a month or so, so I have some time to think it over. My turntable is a Harman/Kardon T20 from the mid Eighties. It got good reviews in its day - does anyone have experience with them?[/quote]

A little, and it was indeed a decent turntable. The only down side is that for a long time H-K had close to the worst service operation I've ever encountered. Don't know how they are now. But if it's working, be happy and enjoy using it.

Since you're planning to feed a sound card with the preamp, I think I'd go with the Hagerman; the Marchand may be designed only to feed a high impedance input, which sound cards aren't. The Hagerman will do it fine.

Peace,
Paul
 
http://www.groupdiy.com/index.php?topic=23300&highlight=baker+clamp

Page 31 looks to havee a Phono pre in the first NS PDF
 
I suggest you get a calibration album. I believe it has a 1kHz tone you can use to adjust the turntable speed. I had heard about the laser players, but $10,000 Owch!
 
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