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dex Otaku

How To Record From Any Line Source

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So many people ask and reask how to do this, so here's some generalised info on how to copy things from an analogue line-level source.

Since this is generalised, there will be no instructions on how to use your specific model of recorder. If you need to learn how to use manual recording levels, for instance - open your manual. If you don't have a manual, please check here to see if there's a copy you can download: http://minidisc.org/part_Manuals.html

I'm making certain assumptions here, such as:

* You're starting with a blank disc

* You have selected the appropriate mode for the length of the recording you want to make [i.e. SP, LP2, LP4, HiSP, HiLP]

* You know how to set your recorder to use manual level control, and you know how to adjust it

* You know how to use your recorder in general

* You are using consumer equipment as your source

First: an analogue line-level source is basically any piece of equipment that has an output that can be plugged into an amplifier. Usually these are the in form of RCA jacks on the back of the equipment.

While the exact level coming out of any given piece of equipment will vary [CD players put out a much higher level than cassette decks, for instance], this is what the level controls on your recorder are for.

Examples of equipment with line-level outputs are:

* Radio tuners

* Cassette, open-reel, and yes, even component 8-track tape decks

* CD players

* Satellite receivers

* VCRs [both mono and stereo]

* Camcorders / video cameras

* DVD players

* Home stereo receivers [AKA integrated preamplifiers, through their record outputs for cassette decks or VCRs]

* Computer sound cards [though some, especially older ones, have amplified outputs that are meant for speakers]

* DJ mixers

* turntable preamplifiers

* professional mixing boards

* generally, any "component" or "separate" piece of stereo equipment

It's also useful to know that in a pinch, you can use the headphone output of most portables as a line-output. This includes cassette walkmans, microcassette recorders, portable CD players, MP3 players, and the like.

Professional components often use 1/4" or XLR [also known as Canon] connections, which can be either balanced or unbalanced. If you're using pro equipment, this document isn't really for you.

GUIDELINE #1:

* All you need is the correct cabling.

Or at least, all you need to hook up the equipment is the correct cabling. wink.gif

There are only two cable types commonly used for recording from an analogue source to a portable MD or HiMD -

1) Dual-RCA to 3.5mm [or 1/8"] stereo cable

This is the same kind of cable usually used to hook up a computer's sound card to a stereo system. On one end are two male RCA plugs [the standard connector type used by almost all consumer audio equipment] and on the other is a plug that is of the same type used by most earphones.

The RCA plugs go to the stereo equipment's OUTPUT [on cassette decks this is sometimes labelled as "PLAY"] and the 3.5mm plug goes to the LINE IN on your portable.

2) 3.5mm to 3.5mm stereo cable

This kind of cable is commonly used for connecting a computer sound card to a Minidisc recorder. One end goes to the OUTPUT or LINE OUT of the equipment used for playing, the other to the LINE IN on the portable used for recording.

Note that there is a difference between mono and stereo cables: a mono cable will have a tip and sleeve [two contacts for two wires]. A stereo cable will have a tip, ring, and sleeve [three contacts for three wires] which is why these are also known as TRS connectors.

Other cabling requirements that you might run into include those using 1/4" or XLR connectors, especially if the source is an instrument amplifier, mixing board, or any other pro or semi-pro equipment. If you're using these as a source, I'm going to make the rash assumption that you probably already know what you need, so I'll just skip going into these more specifically.

Some older European stereo equipment will have DIN connections on them; these use a connector that is much the same as old MIDI cabling or the type used by older PC keyboards, that have a round shield with multiple pins inside for the various signals. If you have DIN-connected equipment, I'd suggest asking at a stereo shop if they sell or can get a cable that will work for you. To my knowledge, these are no longer common, though since I don't live in Europe I honestly can't be certain.

GUIDELINE #2:

* Use manual record levels whenever practical and possible.

Most portable recorders have the option of using either auto gain control [AGC] or auto-levelling, or manual level control.

Since it can be difficult to predict exactly how high the levels are going to be coming from any given piece of equipment, you will generally get better results when using manual level control.

Sometimes, such as when recording from a radio, it's more practical to leave AGC on as long as the average levels don't end up with the recorder's meters sitting smack up at the top.

In the case of certain really dynamic sources, especially HiFi videotapes and DVD soundtracks, it may also be preferable to use AGC - this way you don't end up riding the volume control when listening later. You do sacrifice the dynamic range of the source this way, but sometimes it's easier to deal with a compressed recording [i.e. one made with AGC] than it is to deal with blowing your eardrums out every time a loud part comes up.

GUIDELINE #3:

* If your source has any kind of processing such as EQ, AVLS, a spatialiser or what-have you, TURN IT OFF.

This may all seem pretty simple and self-explanatory to some, but many people don't realise that most consumer audio equipment that isn't totally integrated [as most bookshelf and boombox systems are] have line-outputs on them, and that these outputs follow certain standards for level and connections. Yes, the standards get fudged heavily a great deal of the time, but with correct cabling and some manner of controlling record levels this is usually fixed quite easily.

Moving along...

SUGGESTED PROCEDURE:

1) plug the appropriate end of your cabling into the output of the playback source

2) plug the other end into the LINE-IN of your portable recorder

3) set the recorder for manual levels (how this is done will depend on your recorder, so there is no way I can tell you how to do this in general terms)

4) if setting the recorder for manual levels did NOT involve putting it in RECORD-PAUSE, do this now

5) start whatever the source is you'll be recording from [i.e. turn it on, tune in the station, press play, or whatever it is you need to do to get sound coming out of it]

5a) if possible, play back the loudest known passage in whatever you're recording from - some sources, such as HiFi VHS recordings and DVD soundtracks, are far more dynamic than most music and will have peaks that are much, much higher than the average pop music recording or radio broadcast

6) set the levels so they average [on Sony units] at the hash-mark halfway across the level meters; make sure the levels do not peak at or above the top mark of the meter

6a) if you have no control over where the source begins [as with a TV broadcast], but you know that the source is bound to get a lot louder than the speaking portions, set the levels lower to make sure there's headroom to get those peaks without distortion

6b) hint - especially in the case of TV and radio: wait for a commercial, and use it to set your levels; commercials are generally much louder than the programmes they accompany, so they make a safer reference in many cases

7) restart and pause the source [if possible]

8) start the recorder, then unpause the source if needs be

There you go, you're recording. smile.gif

And oh yeah, don't forget -

9) press STOP when you're done and WAIT for the recorder to finish writing its data and the disc's table of contents [TOC] before ejecting

Depending on what recorder you're using, track marks may or may not be added automatically [and sometimes where you don't want them].

In any case, most MD recorders have a button to add track marks manually while recording.

Naturally, you can pause the recording to get rid of commercials or edit them out later.

Optional stuff:

An additional hint for anyone recording from a portable to a portable:

If the portable used as the playback source is older and takes more batteries [in which case it will have a much louder headphone output], it helps to start off by turning its volume control to around the 2/3 position. In the case of recording from another MD or HiMD that uses only one battery as power, this still generally applies; volume settings above about 25/30 on HiMDs will result in soft-clipping distortion, similar to the effect of AGC, with programme material that is very loud. This is basically the result of the headphone amp crapping out as it reaches the limits of the power supply it has to deal with.

Suggestions for those of you recording from a PA amplifier with TAPE OUT connections:

Some PA amplifiers, especially really common ones [for North America at least] like the Peavey XR- series, have TAPE OUT connections on them.

These outputs often bypass the amp's built-in EQ which is meant for the speakers, so don't worry so much about turning the EQ off in these cases.

In most cases, it's easier to leave AGC on when recording from this type of source; the output generally follows the consumer standard for what line-level is and should average well below the limit above which the AGC kicks in with compression - unless, of course, some very loud guitars are going through the amp or something.

Since most of these types of amps have mono outputs, this leads to the next point...

Notes on recording from mono sources:

There are three ways to record from a mono source:

The first way, possible only with traditional MD equipment you can use MONO mode. Since HiMD recording modes do not have the MONO option, the second and third are most important here.

The second way is to split the signal with a y-adapter or use a mono-to-stereo adapter to plug into the recorder. This way you are recording the same signal on both channels.

When recording a split-mono signal, using lower-bitrate recording modes [such as LP2] is more than a reasonable compromise; because most lower-bitrate modes use joint stereo [m/s] encoding, putting a mono signal into them results in basically getting all of the encoder's bits working for just the one [mono] signal.

In plainer English, this means that recording a mono signal at a given bitrate with joint-stereo encoding result in the same quality as recording a stereo signal at twice the same bitrate. Clear as mud?

The third way is to plug the mono source right into the recorder with a mono cable. This will usually result in the sound being recorded only on the LEFT channel, and what I mentioned above applies to this method as well.

Do NOT try to record a mono signal by plugging only one half of a stereo cable into the source, though. This will usually result in a ground loop [hum in the opposite channel from the connection being half-open] and will mess with the encoder. You will often get hum in BOTH channels, not just the opposite, if you try to do this.

Note that you can use the cheezy hack method to fix this problem by taking a piece of aluminum foil, or basically anything metal [i've used alligator clips for this before] to ground-out the second channel by making [electrical] contact between the pin and shield of the "floating" connector.

Notes on recording from surround-sound sources:

This one is long and more technical, so if you're not interested in doing this, it's safe to skip it.

Dolby Surround and other forms of surround-sound encoding that encode multiple channels into stereo for compatibility all rely on the same general techniques for encoding and decoding.

This is called matrix encoding, and in its most basic form [old-style Dolby Surround] rely on having the front channels in phase and the back channel recording on both the left and right, with one channel 180 degrees out of phase.

That may be Greek to you, but what it means is that this is not usually any more complex than any other stereo signal.

The important thing here is that you can record stereo-encoded surround sound on any type of [stereo] equipment, and likewise decode it later as surround sound.

It does make a difference what encoding mode you choose, though.

PCM, SP, and HiSP modes will work best for reasons I'll explain in a minute.

Lower-bitrate modes such as LP2 and HiLP should still work, though the results [especially if played back through a surround decoder] might be rather dismal in terms of sound quality.

LP4 and 48kbps HiLP are basically useless for surround sound.

The trick here is that lossy encoding formats, regardless of whether they use dual-mono [stereo] or joint-stereo encoding, will generally end up with more artifacting that is out of phase than in-phase [presumably because it masks easier]. This means that the rear channel will end up having a kind of "AM radio in a tin can in a filled washing machine" sound about it.

For those of you who don't believe me, take a 128kbps MP3 of literally anything and play it through a surround decoder with only the rear channels turned up. If the material is surround-encoded, you'll get the surround channel in there pretty clearly most of the time, but in either case you'll also end up with loads of artifacting from the front channels that normally don't end up getting heard at all.

Technically, there should be no major difference between how true stereo and joint stereo [m/s, not intensity stereo] encoding will affect a surround sound programme. Certain lossy formats will be better than others at it, and it's pretty hit-and-miss as to which ones are truly better than others.

The general rule here is that higher bitrates will always work better, because the less artifacting there is, the better the results will be. Lower bitrates will generally end up mungeing the rear channel with artifacting from the entire stereo signal.

That's it, kids.

Addendum [2005-06-11]:

What if the source has only a headphone output, or has an easily-accessible headphone output [such as a TV]?

This was mentioned above, but not referred to specifically.

You can record from a headphone output as if it were a line output, yes.

My suggestion is to follow the suggestions above [especially about disabling all unnecessary audio processing], and:

* Set the record levels on your your recorder manually to unity gain; on HiMDs this is about 18-19/30

* Set the headphone or device volume to about 70% to begin with

* Adjust the output level on the device [the volume control] so that levels "fit" on the record meters, i.e. averaging around the first dot [-12dBfs] and peaking below the second dot [0dBfs]; the meters may not look the same on all units, so check your manual for more info

* If the levels on your meters are still too low, use the recorder to adjust them upward

* If the levels on your meters are too high, even with the device turned most of the way down, you will likely need to use something like the Radio Shack Headhone Volume Control to attenuate them

Edited by dex Otaku

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Pinned. Bravo Dex, you've outdone yourself here in your time at the forums. I really cannot thank you enough for your consistant and well thought out contributions. *hail*

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If anyone has a scanner or digicam and some audio equipment handy, the following pictures would be helpful to go along with this:

* RCA outputs on the back of an a/v component

* a 3.5mm stereo to dual-RCA cable

* a 3.5mm stereo to 3.5mm stereo cable

* a 3.5mm mono plug for comparison

* 1/4" TS and TRS plugs

* an XLR connector [female]

* the back of a pro audio component with 1/4" and XLR jacks

* a DIN connector and the DIN in/out on the back of a component

Yep.

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i might be able to help with the pics but i got nowhere to host them currently

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photobucket.com

I prefer to know the source of what I post, and to know it is legal.

I have found my own photography on such sites, and do not approve of it.

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i might be able to help with the pics but i got nowhere to host them currently

You can email them to me, and I can host them until kurisu can get them on the MDCF server.

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You can always use attachments in posts..and then I could just upload them to our images directory.

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Great work Dex! You might want to expand on the "Manual Record Level" settings a little more. Although its different on different units, some good pointers would be how to use the level meters on your (Hi)MD unit to obtain the optimal signal. How loud is too loud? What volume should users be aiming for? Is it better to be just avoiding distortion, or to have a margin in between the peak levels of the recording, and the distortion levels? And what are the peak and average levels of a recording and why should the average user care?

Perhaps not as detailed as that, but something explaining what level users should aim for would be cool.

Damn, we really need that wikki!!!!

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Great work Dex! You might want to expand on the "Manual Record Level" settings a little more. Although its different on different units, some good pointers would be how to use the level meters on your (Hi)MD unit  to obtain the optimal signal. How loud is too loud? What volume should users be aiming for? Is it better to be just avoiding distortion, or to have a margin in between the peak levels of the recording, and the distortion levels? And what are the peak and average levels of a recording and why should the average user care?

Perhaps not as detailed as that, but something explaining what level users should aim for would be cool.

Damn, we really need that wikki!!!!

You don't think step 6 is clear enough?

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Sorry, I was reading the wrong part of the post. Yeah, step 6 is clear enough.

On my 510 I always set it so it lights up the 2nd last bar on the level meter (as it specifys in the user manual), lighting up the last one will cause distortion. Probably a good rule of thumb for Sony units (light up the 2nd last bar), but I might be mistaken in this since the Hi-MDs might be different.

On reading the original post again, it's an excellent guide, I don't think much need changing at all.

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If anyone has a scanner or digicam and some audio equipment handy, the following pictures would be helpful to go along with this:

* RCA outputs on the back of an a/v component

* a 3.5mm stereo to dual-RCA cable

* a 3.5mm stereo to 3.5mm stereo cable

* a 3.5mm mono plug for comparison

* 1/4" TS and TRS plugs

* an XLR connector [female]

* the back of a pro audio component with 1/4" and XLR jacks

* a DIN connector and the DIN in/out on the back of a component

Yep.

I have put up a schematic which I have successfully used to connect to/from an XLR based system (Yamaha MC1204 mixing desk)

http://lamp.man.deakin.edu.au/junk/trs2xlr.gif

[attachmentid=59]

Please note that this assumes standard XLR pin 2 high. Older (especially USA) equipment may have pin 3 high! Failure to use correct wiring will probably blow the expensive bit plugged into the XLR!

Cheers

Goaty

post-6186-1108952919.gif

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