Keyboard Magazine "In The Studio" Sync Tone and Click Track on Tape
Since this is the first in a series monthly columns written by me, I'd like to start from the begining.
If you own a drum machine and/or a sequencer, and a tape recorder, I hope this article will help you to get the most out of today's technology. If you don't own any of the above , but plan to make use of them in a recording studio, then this article is for you too!
There are many misconceptions concerning interfacing sequencers, drum machines and synthesizers to a tape recorder. The key to making them sync up with a tape recorder is the sync tone. The Linndrum, DMX, DSX, Drumtracks, TR909, MSQ700, Microcomposer 202, MPU-401, Drumulator, RX-15,RX-11, MXR , Polysequencer, SCI/Commodore 64 sequencer, PPG Wave 2.2 & 2.3 and the Oberheim DX (with a mod ) can all generate a type of sync tone called FSK. Each one of the above mentioned units can read this tone after it has been printed on tape and sync up again to it. One problem that most musicians have had is getting a different manufacturers drum machine to work with another manufacturers sequencer and vice versa. Another problem for many musicians that own drum machines and sequencers not included in the above list is they have had to purchase an interface device developed just for this purpose (i.e. Dr.Click, the Mini-Doc, Nano Doc, FSK and MIDI Adapters, The Byter Interface, KMS-30 MIDI Syncronizer). But the biggest problem of all for many musicans, is using the correct procedure to record sync tone and /or click track.
Whether you are recording on a four track or a twenty-four track is really all the same when it comes to recording sync-tone. The question of whether to print the drum machine or the sequencer's sync tone first is really a matter of taste. For most musicians who will be quantizing their sequences, good practice to program your drum machine first so you can check your sequences against the drums as a reference. Before attempting to record your sync tone, make sure the heads are clean and your recorder is properly alligned. If you lack the skills and/or the proper test tapes and calibration gear needed to do an allignment, be sure to stick to the manufacturers recommended tape type. The level you record sync at is most critical. Poorly recorded sync ( too hot or too low in level ) will most assuredly have dropouts and will be totally unusable. In the studio, consoles and tape recorders operate at +4db as compared to semi-pro gear which operates at a -10db level. The best level to record sync tone in a professional recording studio is around -10db. On semi-pro gear -3db seems to work best. Never use noise reduction on your sync tone tracks. On many semi-pro recorders equipped with dbx or dolby you don't have a choice of turning off the noise reduction, so some experimentation with different levels on your deck will tell you if your drum machine will read sync that has been encoded with noise reduction. I've used a Linndrum and the DMX with a Tascam 244 portastudio ( which has dbx) and the -3db level seems to work fine. Never equalize or compress your sync tone track when recording it either. If at all possible patch directly into your recorder bypassing your mixer. This will insure a good clean signal to tape. To adjust level use the input level control of your deck. You must give up a track to have sync tone on your tape. Sync tone can not be shared with any other audio tracks bounced to one track. This might seem like a great compromise for a four track user, but if your sync tone is recorded properly, your drum machine and sequencer do not have to even be on the tape. You just have to start the song fom the top every time. If you are using an eight track you can record the drums on another track in mono( which will make overdubs easier) and then use the drum machine in sync with the tape for the mix. The advantage is clear, there is nothing like first generation drum sounds in your mix. As to what track is best to choose, I would suggest an edge track. Theoretically edge tracks of any multi- track recorder should not be used for high fequency data (such as sync tone), but the studio standard for sync tracks and SMPTE has been tracks 1 or 24 . If you are using SMPTE ( for 48 track or video , track 24 is the standard to print SMPTE code on) track 23 is sometimes used for sync tone or click. I will cover the use of SMPTE in months to come. Never record program material with high transients next to your sync track. Semi-pro recorders have lower levels of crosstalk rejection. Tambourine and hi hat recorded at hot levels on adjacent tracks are prime offenders in causing dropouts on sync tracks. This holds true even on sync tracks that have been known to be good until a high transient sound was recorded on an adjacent track next.
Now the next step is to choose your tempo carefully.Once you stripe the tape with a sync tone you will not be able to change the tempo of the song later ( unless your deck has vari-speed capability). At this point don't record the audio from your drum machine or sequencer. The reason for this is that if you record the sync tone first and then on the next pass play it back into the drum machine/sequencer and record the audio, you will be accomplishing two major things. First, you will be verifing the sync tone track on tape. Many people who record sync tone and audio simultaneously aren't verfing their sync and when they come back later for an overdub either the sync is no good because of drop outs, poor level, or the noise reduction syndrome that we spoke of earlier. Or, there may also be a lag sometimes when reading sync off tape and overdubing new audio with the existing audio tracks. So if you print the audio of your drum machine and /or sequencer at the same time as the sync tone track, you run the risk of having lag on your overdubbed tracks. In the studio it is a rule that the sync tone or click track is always recorded first and then the audio is always recorded on the next pass. This way, if there is any lag, all the tracks will have the same amount. Up to now we've been talking only about sync tone. At Unique Recording Studios with so many different manufacturers drum machines and sequencers to choose from, we've adapted Dr. Click into the procedure. The process is very similar to recording a sync tone except that you are recording a square wave pulse trigger . This square wave trigger sounds like a click track and thus solves two problems for us. It serves as a metronome for musicians (since we usually record it at 1/4 note value). And we've found that a 1/4 note click is truly what Dr. Click wants to see to generate all the available clock outputs (i.e. 12,24,48,64,96,and 384 beats per 1/4 note plus 1/8,1/8t,1/16,1/16t,1/32,1/32t, etc.) Unfortunately Dr.Click is quite expensive for most. If you are using the Mini-Doc , Nano- Doc, FSK or MIDI Adapters or the Byter interfaces you cannot use a 1/4 note click track to drive them. Instead they would prefer a 96 FSK ( Oberheim standard) sync tone. Although they will work with the slower FSK (48 or 24 ), it is always best to divide down from the master sync tone then multiply up. The Linndrum can be used to read its own sync off tape and then similtaneously generate either a 96 , 48, and 24 per 1/4 note clock, limiting the need for an interface box.
With the advent of Midi-clock Many of the newest drum machines and sequencers (i.e. Yamaha's RX-15, RX-11, QX-1, Roland's TR909, MSQ700, MPU-401, Linndrum 9000, and the Emulator II) will be most dependent on the sync tone track. The best part of MIDI clock is that it is a standard. You will only need one interface to read sync off tape and translate it into MIDI clock. The newer sync tone tracks will offer the user the ability to sync the device to tape in a SMPTE transport fashion. The user will be able to fast- foward, rewind, stop and play the tape from any part within the song and the device (provided it is in song mode) will slavishly stay in sync with your 4 track, 8 track, 16 track, 24 track or whatever. Roland's SBX-80 Sync Box can read a 1/4,1/8/1/16,etc note click from tape and generate either 12,24,48,96,and 120 beats per 1/4 note clock or MIDI clock. The SBX-80 can keep your MIDI clock devices in sync with a tape recorder by reading a SMPTE track (there is a SMPTE generater /reader built into the SBX-80) and a click track (there is also click track generator as well). Its a great system but you have to give up two of your tape recorders tracks (one for the SMPTE and one for the sync/clock/click). This is not very economical track wise if you are recording on a four track, but as I've mentioned above, your drums and synthesizers do not have to be on tape. The new Linndrum 9000 accomplishes this by generating its own sync track that offers the user the same results as the SBX-80 but by only taking up one track.
But as I've stated before ; the sync track should always be recorded first, verified and then you know it's truly a sync track!