Sorry, in het engels, maar wel zeer uitgebreid
I am not a digital audio professional. Transferring LPs to CDR is my hobby,
born of the desire to preserve those parts of my LP collection which (i)
are unavailable on CD, or (ii) aren't essential enough to me to be worth
spending the money replacing them on CD.
My standards are high. I have a stereo system which all but a small
minority of audiophile extremists would regard as "very high end".
I'm not interested in putting anything onto a CDR unless I can get
fairly close to perfection. The advice contained in these notes is empirical, and results from my own
I work on a PC, and can only offer advice in that arena.
I have no knowledge whatsoever of doing this kind of work on
Macs or Unix machines.
At the end of this document is a list of useful URLs.
Slightly off-topic: why use a computer?:
I got some email from someone who asked me to add a short paragraph
discussing alternative methods of archiving LPs without using a computer,
so I have done so at the end of these notes.
The task of transferring an LP to CDR comprises 4 basic steps:
Recording the LP to hard disk.
Cleaning up the vinyl damage using a computer based WAV file editor.
Preparing the tracks prior to burning.
Burning the CDR.
Recording the LP to Hard Disk
Clean the LP
Before you start, you should do your best to clean the record as
thoroughly as possible; getting dust and gunge out of the grooves will
eliminate a fair amount of the lower level noise that would otherwise
require a very time-consuming job to remove at a later stage.
Ideally use a vacuum device; even better get them professionally cleaned
by someone who has access to a Keith Monks cleaning machine.
Playing the LP
Use a good quality turntable to play the LP. The pickup cartridge should
be properly aligned and the stylus should be in good condition and clean.
A turntable is a mechanical device which is vulnerable to airborne and
floorborne vibrations. Such vibrations can degrade the playback quality
quite noticably. Even the very best turntables can suffer in this respect.
Therefore, while recording the LP, keep surrounding sound levels as low
as possible. Ideally you should not use any kind of monitoring at all;
don't worry about knowing when the music starts and ends, just start
recording from before placing the stylus on the lead-in groove and
continue recording right into the run-out groove (trimming off these
extra bits later is easy).
I will assume that you will use a moving magnet or moving coil cartridge
(all high quality cartridges are one of these two types). The signal off
such a cartridge is both low in level (typically <5mV for moving magnet,
<0.5mV for moving coil) so must be boosted to about 100mV needed to drive
line level inputs, and is also RIAA equalised (applied when the LP is
mastered to get around mechanical limitations of the LP system) which
must be reversed so as to provide a flat frequency response for the line
input. Both of these necessary operations are achieved with a suitable preamp. If you have a receiver or
stereo amplifier with a "phono" input, that input will perform this task, and the resulting line level output will
be available on the receiver/amplifier tape output. Tom Weber informs me that Radio Shack sells an
inexpensive amplifier (model number SA-155) for about $65 which is suitable, and I pass on his
recommendation here while emphasising that I have no personal experience of this device. I believe that
Radio Shack also sell a standalone phono preamp for about $30. If you have higher quality equipment such
as a separate preamp and poweramp, you'll know what I'm talking about and I leave the choice of a quality
phono stage up to you.
Recording to Hard Disk
Once you have a line level signal, it needs to be digitised and recorded
onto the computer's hard disk. Note that for a typical 40 minute LP,
you'll need about 500Mb of disk space, and depending on what PC editor(s)
you use, you might need another 500Mb for temporary files.
Count on needing about a gigabyte in total.
The standard Sound Recorder utility that comes with Windows is not
suitable for this task because it records to main RAM and only writes
the results to hard disk when recording finishes. This means that recording
time is limited by the amount of RAM in the PC; since 16 bit stereo at 44kHz
uses about 10MB per minute, there's no way you'll be able to record an entire
LP side using Sound Recorder. What is needed is a utility that can record
direct to the hard disk. There are a large number of such utilities available
as shareware. My own shareware Wave Repair supports hard disk recording,
has rather better record level metering than most other packages, and if
used as a simple record utility it is freeware. Of the other packages around,
probably the cheapest is CD Wave. Two very good general purpose WAV file
editors, CoolEdit 2000 and GoldWave, also offer direct to hard disk recording.
Once you have a package capable of recording direct to hard disk, there are
two basic approaches to digitising the line level signal depending on the
quality you require:
Use a "normal" computer soundcard. You need a soundcard capable of
44.1kHz 16bit stereo. All modern soundcards are able to do this.
The (analogue) line level signal should be fed into the line input of the
soundcard, and the signal can then be recorded straight to the hard disk.
Use an outboard analogue-to-digital convertor, and feed its (digital)
output into a soundcard capable of receiving digital signals.
As with using a "normal" soundcard, the analogue signal must be sampled
at 44.1kHz stereo. If you use an A/D convertor which is capable of more
than 16 bit resolution, you might wish to find a soundcard that can
maintain those bits (although you will of course have to convert
to 16 bit before actually burning a CDR). However, my own experience is
that even the most perfect of LP sources will be hard pressed to deliver
a signal with more than 12 bits resolution, so plain vanilla 16 bit is fine,
and even truncation without redithering won't harm the LP signal.
Using a "normal" soundcard is certainly a much cheaper option,
but the inside of a PC is a very hostile environment for analogue signals.
Some soundcards are better than others in their rejection of this noise
pollution. Among affordable brands, Turtle Beach have a good reputation.
The old Ensoniq Audio PCI, which was a very popular high quality soundcard,
was taken over by Creative and it appears is now discontinued.
The ultimate in quality for "normal" soundcards probably remains the
Digital Audio Labs CardD+, but this is about $500. Another company
whose soundcards have a very good reputation is Event Electronics;
their Darla, Gina and Layla systems have all been recommended, but you
should keep in mind that these are primarily multitrack recording systems,
so could be considered overkill on the features front if all you're doing
is recording stereo. In general, Soundblasters perform poorly
(with the possible exception of the Live! and AWE 64 Gold, which
some people say have quite good sound quality; I've not used either,
but can report that my experience with an AWE 64 Value was not good).
Most cheap unbranded Soundblaster compatibles have simply dreadful
http://www.pcavtech.com/soundcards/index.htm and http://www.rockpark.com/soundcards
have a lot of good information about analogue soundcards.
As for soundcards which can receive a digital signal, there are a host
of options. The cheapest I know to work well is a "digital-only" version
of the DAL CardD at about $300, but this only supports COAX SPDIF.
Two other highly regarded cards are the Zefiro ZA2 and AdB MultiWave Pro,
both of which support COAX and optical SPDIF and professional AES/EBU
standards; these two cards are about $450. Midiman are in the process
of releasing a pair of SPDIF I/O cards: the DiO-2448 supports up to
24bit/48kHz, and the DiO-2496 goes up to 24bit/96kHz; they both include
an analogue output for monitoring purposes. I haven't heard any reports
of how well they work, but they will be fairly inexpensive and,
being PCI cards, will be future-proof against motherboard upgrades.
A couple of older Turtle Beach cards, the Fiji and Pinnicle,
have daughter board options to provide SPDIF I/O and are known to
work well, but may be getting difficult to acquire now that they are
out of production. Three inexpensive cards have recently come on the
scene which can have an SPDIF daughter board added:
Turtle Beach Montego II, Creative Soundblaster Live, and Hootech ST Digital XG.
However, all three resample the SPDIF input to an onboard clock rate, so
they do not allow for bit-perfect transfer of external digital audio to
the hard disk. Previous versions of this page mentioned a card from a
German company called Scalacs, but I have contacted them and the card is
no longer available. A company called Opcode made a device called the
DATPort which allows SPDIF signals to be transferred via USB ports,
but I have seen many reports that it is very difficult to get working
reliably, and since Opcode were taken over by Gibson it appears that
no support is available. And finally, you may hear stories about $20
soundcards with SPDIF I/O. Various people have tested these cards and
in the vast majority of cases could not make the SPDIF I/O work properly.
Even those few people who did have success needed to build extra bits of
http://www.digitalexperience.com/cards.html has a lot of good information about
The following tip comes courtesy of Richard Melton:
When using an analogue soundcard, it is often a good idea to mute all
inputs and outputs that aren't actually being used (eg. mic, MIDI, etc).
This will improve the noise performance of many soundcards.
Note that some soundcards have a "calibration" function, which should
be re-run after changing the input configuration.
Humming Along with the Music
It's quite possible that when you hook up the line level output from the
LP playback system to the input of your PC's soundcard, a hum will result.
This is due to problems with the ground connections on various parts of
the whole setup (usually the PC's ground and the stereo system's ground
are at different voltages).
Trying to rectify this kind of hum can be problematic, but a few things
to try are:
Check that all the components in your stereo system and the PC are actually
grounded; leaving off a ground can easily cause hum.
Plug all mains electrical items (ie. all stereo components and the PC)
into the same mains outlet, using multiway adapters as necessary.
(The power consumption of all these kind of devices is so low that this
will not overload the outlet). This forces all the components to share
a common ground, which might fix the problem.
If sharing the same outlet doesn't help, you can try disconnecting the
ground connections from some components. Start with the turntable itself.
If this doesn't work, check to see if the turntable's connection to the
preamp/amp/receiver has a separate ground wire and try the effect of
attaching/removing it from the preamp/amp/receiver's grounding post.
If you still have no luck, try disconnecting the preamp/amp/receiver's
ground (both with and without the turntable ground re-connected).
However, beware of any dire warnings in the manufacturer's manual about this:
in many cases it will be safe, but some components might not have insulated
Rod Smith tells me that cable TV connections can sometimes cause a ground
loop if they are fed into the stereo system. In this case, the simplest
solution is to disconnect the cable TV output from the stereo system
while recording into the computer.
George Koulomzin suggests another experiment. If you have mains plugs
that can be inserted either way round, try the effect of reversing one
or more of them. This alters the relative phase of the mains to the
components, and it may cause the hum to cancel out.
Stores such as Radio Shack sell small transformers known as
"ground loop isolators". These can cure some types of hum problem when
connected between the stereo system and the computer.
If all this fails, then I'm at a loss as to what you might try,
short of removing all grounds from all components, bundling them
all together and strapping them to a copper pipe buried in the (real) ground!
Setting Record Levels
Whether you choose to go with a "normal" soundcard or external A/D convertor,
it is important to set the input levels accordingly. The aim here is to
get peaks as close to 0dB as possible without exceeding that level.
This is for two reasons:
It uses the maximum resolution available with the 16 bits.
Having said this, since an LP signal manages about 12 bits resolution
at best, you could in theory afford to leave a huge headroom
(eg. peak around -12dB or even less) without losing resolution.
(Less obvious but probably more important) If you record at a low level
and burn a CDR, you will end up with a CD that plays too quietly in
comparison to your other (commercial) CDs. While it is possible to bring
the level up using the "normalisation" feature of many WAV file editors,
such normalisation is never perfect (the arithmetic that is performed
results in rounding errors), and so it is better to avoid this if at
As a guide, I tend to pick what I think is the loudest part of the LP,
and set record levels to register about -3dB for that part, which
leaves a little headroom in reserve.
Unlike recording to analogue tape (where pushing the signal level well
past the nominal maximum level can sometimes be a valid approach)
it is absolutely crucial that you never exceed the 0dB level.
If you do, the result is digital clipping; an extremely unpleasant-sounding
type of distortion.
When recording an LP to hard disk, don't be tempted to try and split
the tracks at this stage. You will want to retain the correct timing of
inter-track gaps on the final CD, and it is much easier to split the tracks
and retain the correct length gap using a PC editor later.
(Indeed, you may use a CDR burning package that doesn't need the tracks
to be in separate files anyway).
Cleaning up the Recording
Once the signal is on hard disk, the hard work begins.
Before we start, let me state from the outset that many people hope to
find a single software package that will do everything they need.
This is an unrealistic expectation; in general you will need a toolkit of
various packages. In the notes which follow I will point out the strengths
of those which I have personally used, and in passing will mention other
packages which I have not used but nevertheless have a good reputation.
Most people will be recording from stereo records. However, if you want
to transfer a mono LP there are a few extra issues to consider which
I'd like to deal with first. A CD cannot be mono; you must record it in
stereo. The ideal situation is that the two channels are identical,
but if you just play a mono LP on a standard stereo turntable,
the chances of getting identical left and right channels is virtually nil.
It way well be that they are close enough that the results sound fine and
you don't feel the need to change anything.
However, what if the two channels are sufficiently different that the
results are not really acceptable mono? To arrive at two identical
channels, there are basically three options:
Merge the two channels together and duplicate the results to both left
and right. You may find that some surface noise cancels slightly this way.
Duplicate the left or right channel to both channels. This would be
appropriate if you decide that one of the two channels is markedly better
than the other. The most likely reason this might be the case is when one
of the groove walls has worse damage than the other, allowing you to select
the channel with less surface noise and/or clicks & pops.
Some intermediate stage between the two above options, whereby the
channels are merged but a weighting is applied so that a greater
proportion of one channel is used than the other.
Either of the first two options can be achieved with creative wiring of
the turntable's cartridge, but a weighted merge is only really possible
using a mixer. You can of course deal with it all in software once the
signal is on hard disk, and this is the course I'd recommend.
One advantage to recording the two channels to hard disk as stereo is
that if there is a click on one channel only, you can copy over a clean
section from the other channel. Only after this stage would it then be
appropriate to start mixing the channels to mono. CoolEdit 2000 is probably
the best affordable tool for this kind of channel merging operation,
using its channel mixer.
Trimming Out Unwanted Sections and Fading In & Out
These are essential steps, and can be done easily using a wide variety
of WAV file editors. Two affordable shareware editors that I strongly
recommend are GoldWave and CoolEdit 2000. My own shareware Wave Repair
can also trim off unwanted sections. Try to get the start of the WAV
file as close to the beginning of the music as possible, leaving perhaps
a quarter second in reserve. Once you've trimmed this excess at the start,
edit the first few samples to make sure they are zero on both channels and
then fade in the next few samples (making sure you get to full volume by
the time the music starts); all this messing about is to get a nice clean
start to the CDR without a click. The same procedure is required at the end
of the LP, although here you should aim for a longer, gradual fade out.
I like to add a little extra silence at the end; this is because some
CD players make quite a bit of mechanical noise at the end of a CD
(eg. relays switching, laser sleds parking, etc), and I prefer this not
to happen the instant the music finishes.
Removing Clicks, Pops and Noise
Even the best LP will have some minor clicks that you'll want to remove.
Some very old records might have so much tape hiss you'd like to reduce
I'll deal with removing constant noise first, as this is easiest to deal
with. CoolEdit 2000 has a fine broadband noise reduction mechanism:
you select a region that is only noise, and CoolEdit samples it;
you then select the region to be noise-reduced, and CoolEdit subtracts
the noise spectrum from the selected region. This works well, but for
tape hiss can cut out quite a bit of the high frequency programme content.
It should also be used in moderation, since it can impart a sort of
"metallic, robotic" sound to the music if you use it too enthusiastically.
You might instead try playing around with GoldWave's parametric EQ,
using fairly steep notch filters; this can sometimes work well.
Another package which deserves a mention is DCart. This has a fairly
good dynamic noise limiter, which varies the amount of hiss reduction
based on the amount of high frequency signal that is present.
When there is a lot of high frequency energy, the amount of hiss reduction
is small; this takes advantage of the fact that the high frequencies
that are present mask the hiss. When there is little high frequency content,
the amount of hiss reduction is high, and the loss of what little high
frequencies there are isn't very noticable.
This approach can work remarkably well, especially on "busy" music,
although it pumps badly on some kinds of signal (eg. solo piano).