Topic: Digitizing from LP

[zowie]

Agree with SparkE - gotta have the riaa eq.  Though I can't help but think good mic pre-amps are better then all but the best hifi pre amps.  I've been wanting to try the v3.

Actually, you can apply RIAA eq via software after you record.  That certainly wouldn't be my preferred way of doing it if I were making archival copies, but if you're just looking to make cds of lps to share with a friend or play in the car or something it's okay.

[Dr.FOB]

Applying the RIAA eq after recording can be done with any number of sound editing packages.
http://www.a-reny.com/restauration/avance.html illustrates the filter construction in Cool Edit. 
Note the advice that recording at -20 db is important so as not to cause overload upon eq.

So if anyone that has an old out-of-print vinyl library starts transferring via V3 @ 24/48 or 24/96, keep us in the loop.

[SparkE!]

Applying the RIAA eq after recording can be done with any number of sound editing packages.
http://www.a-reny.com/restauration/avance.html illustrates the filter construction in Cool Edit. 
Note the advice that recording at -20 db is important so as not to cause overload upon eq.

So if anyone that has an old out-of-print vinyl library starts transferring via V3 @ 24/48 or 24/96, keep us in the loop.

The advice to run at -20 is the very reason that it's best to do this with real RIAA equalization in the linear world.  By recording at -20 dB, you lose 20 dB of dynamic range.  I realize that most LPs don't have more than about 75 dB of S/N, but that's no reason to waste perfectly good dynamic range.  You're starting off with an absolute maximum of 107 dB of dynamic range (if you're using a V3) and you'll probably run 3 to 6 dB below that, so you may only get 101 dB of S/N.  Then subtract the 20 dB of dynamic range and you're at about 81 dB.  That puts your quantization noise at only 6 dB below your noise floor.  That may not be terribly significant, but it's not as good as you'd get if you still had 101 dB of S/N and your quantization noise was 26 dB below your noise floor.

I'd still recommend doing the RIAA equalization in a real amp with the RIAA equalization filter.  You'll get better results if you do.

[it-goes-to-eleven]

I'd still recommend doing the RIAA equalization in a real amp with the RIAA equalization filter.  You'll get better results if you do.

But the question remains about how good the V3 is as a phono amp compared to most pre-amps..  Until someone tries this, I don't think anything is decided.   I am curious how much LP transfer testing you have done and with what gear.

My LP12 turntable needs a tune up and I'll probably spring for a new cartridge. Not sure what yet. That has been holding my testing up.  I guess I'll try and do a run with what I have as a quick test.

[SparkE!]

I'd still recommend doing the RIAA equalization in a real amp with the RIAA equalization filter.  You'll get better results if you do.

But the question remains about how good the V3 is as a phono amp compared to most pre-amps..  Until someone tries this, I don't think anything is decided.   I am curious how much LP transfer testing you have done and with what gear.

My LP12 turntable needs a tune up and I'll probably spring for a new cartridge. Not sure what yet. That has been holding my testing up.  I guess I'll try and do a run with what I have as a quick test.

The V3 is going to work great to record the LP to a digital format and the resulting S/N after you apply RIAA equalization in software will be 6 dB below the noise floor of the signal recorded on your LP.  So from a purely S/N point of view, the resulting recording will have a S/N that is just barely less than that of the signal that was recorded to the LP.  That's pretty good.

What I was talking about is if you wanted to take full advantage of the V3 and reduce the amount of quantization noise that will be added by the process of converting the analog signal to a properly equalized digital signal, you'll use a low noise phono preamp ahead of your V3.  As long as the THD + hum  + N of the phono pre is better than -81 dB from line level and its output is at full line level, you'll benefit from the use of the phono preamp.

The question I think you have is whether you can tell the difference between doing it with or without the phono preamp because you'd like to be able to do it with the V3 alone.  That's a question that no one can answer but yourself.  If your intent is to just get something that's good enough to listen to and sounds pretty much just like the original, then the V3-only approach should work well.  If, instead, you're trying to make an archival copy from the best copy of the LP in existence, then you might want to add the phono preamp.

[Roving Sign]

SparkE - would it be possible to use the V3/no phono-pre approach to capture the signal off the cartridge...and then play that signal back through a phono preamp? Thus adding the RIAA curve...? Adds an extra step - but perhaps also some flexibility...

Using this approach - he could apply this signal to any phono preamp he might have...

[SparkE!]

SparkE - would it be possible to use the V3/no phono-pre approach to capture the signal off the cartridge...and then play that signal back through a phono preamp? Thus adding the RIAA curve...? Adds an extra step - but perhaps also some flexibility...

Using this approach - he could apply this signal to any phono preamp he might have...

You could equalize it at any time, but it seems to me that it's best to end up with a flat recording to begin with.  What I mean to say is that you don't want to store it on CD with the bass attenuated unless you have a way to play it back with the RIAA compensation.  You can't easily do that in your car.

And yes, you could play your RIAA compressed recording through a phono amp, but you'd also have to attenuate the line level signal before it went into the phono preamp.  The phono preamp would bring it back up to line level.  A line level signal would be too hot to drive the input to the phono preamp, so that's why you need the attenuation.  Phono preamps usually provide either 38 or 53 dB of gain.  So, you'd need either 38 or 53 of attenuation ahead of the phono preamp.

[macdaddy]

sparke! is right...

you want the phono stage there to do two things - add gain, and apply the riaa eq. then you are feeding a strong, quality signal to your a/d...

fwiw - i plan on doing this with my newly purchased ua5. i am in the process of building the tubed phono stage, but i am in the early stages of this project, so i wont be transferring for a few months...

but i do have some cassettes to playback, and the 2xrca out of the nakamichi deck will feed the rca in's of the ua5 perfectly...

but with vinyl, you really should have the phono stage in the mix...

i have one of those artusb pre's that i am about finished with - i was gonna send it off to _bob_ to play with if he wanted to check it out. that might do the trick for some of you - but it is limited to 16/48. but it is a phonostage/a>d all in one box...

[Krispy D]

fwiw - i plan on doing this with my newly purchased ua5. i am in the process of building the tubed phono stage, but i am in the early stages of this project, so i wont be transferring for a few months...

but i do have some cassettes to playback, and the 2xrca out of the nakamichi deck will feed the rca in's of the ua5 perfectly...

off the subject of vinyl but on the subject of A>D transfers with a UA5,  does a digi mod ua5 still pass a signal to the usb?  I've got some cassette transfers to do an was thinking of using it.

[SparkE!]

fwiw - i plan on doing this with my newly purchased ua5. i am in the process of building the tubed phono stage, but i am in the early stages of this project, so i wont be transferring for a few months...

but i do have some cassettes to playback, and the 2xrca out of the nakamichi deck will feed the rca in's of the ua5 perfectly...

off the subject of vinyl but on the subject of A>D transfers with a UA5,  does a digi mod ua5 still pass a signal to the usb?  I've got some cassette transfers to do an was thinking of using it.

Yes, I believe that still works.  It's playback from the computer through the UA-5 that gets broken by the digimod.

[Krispy D]

fwiw - i plan on doing this with my newly purchased ua5. i am in the process of building the tubed phono stage, but i am in the early stages of this project, so i wont be transferring for a few months...

but i do have some cassettes to playback, and the 2xrca out of the nakamichi deck will feed the rca in's of the ua5 perfectly...

off the subject of vinyl but on the subject of A>D transfers with a UA5,  does a digi mod ua5 still pass a signal to the usb?  I've got some cassette transfers to do an was thinking of using it.

thanks sparkE. +T

Yes, I believe that still works.  It's playback from the computer through the UA-5 that gets broken by the digimod.

[zowie]

SparkE - would it be possible to use the V3/no phono-pre approach to capture the signal off the cartridge...and then play that signal back through a phono preamp? Thus adding the RIAA curve...? Adds an extra step - but perhaps also some flexibility...

Using this approach - he could apply this signal to any phono preamp he might have...

Besides that I don't see any point in it, I don't think it would work well.  The phono pre will probably be overloaded if you feed it a line-level input.  Even if not, taking a line level and adding another 30-60 db of gain would probably overload the next component down the line (your switching amp or perhaps power amp).   You could try to get around that by recording at extremely low levels but then you'd have excess noise.

[Roving Sign]

I stated the point - you could then route the "catridge capture" to any preamp you might have. - Thats the point. You would have to capture the cartridge signal in such away that when played back - it would produce the same cartridge level - NOT line level. Now - can this be done? I  dont know - not sure what kind of voltage a phono cartridge produces. It is likely a low voltage - and perhaps woud require some sort of higher res A/D...

[SparkE!]

I stated the point - you could then route the "catridge capture" to any preamp you might have. - Thats the point. You would have to capture the cartridge signal in such away that when played back - it would produce the same cartridge level - NOT line level. Now - can this be done? I  dont know - not sure what kind of voltage a phono cartridge produces. It is likely a low voltage - and perhaps woud require some sort of higher res A/D...

That's the reason I said this:

And yes, you could play your RIAA compressed recording through a phono amp, but you'd also have to attenuate the line level signal before it went into the phono preamp.  The phono preamp would bring it back up to line level.  A line level signal would be too hot to drive the input to the phono preamp, so that's why you need the attenuation.  Phono preamps usually provide either 38 or 53 dB of gain.  So, you'd need either 38 or 53 of attenuation ahead of the phono preamp.

But really, that'd be a PITA to have to rig up a special playback system just because you failed to use a RIAA equalization curve on the recording when you did it in the first place.  I'd rather use the special setup once, then listen to the recording on any CD player that I chose to use.  Your way, I'd have to rig something special every time I listened to the recording.

BTW: Did anyone ever use the V3 alone to do the recording?  If so, was it acceptable to your ears?  Did you bother to test the difference between running a real RIAA phono preamp and running the RIAA curve in software?

[it-goes-to-eleven]

I haven't had a chance to do the v3 test yet..  I have done some quick searches and there are bunches of cheap phono pre-amps out there.  It might be interesting to get a minimal device that just does the RIAA EQ but does not otherwise amplify (I haven't seen those).

Is the RIAA EQ typically done before or after the phono levels are brought up?  I'm guessing after but just a guess.