A couple of years ago, Pure Energy supremo Jason Fitzpatrick found that he couldn't economically sync a TB303, which uses Roland's pre-MIDI Sync24 system, to his MIDI gear; so he developed the Clock Sync. Word spread and Jason found himself building this simple MIDI to Sync24 converter for other musicians. The Clock II Sync is an enhanced version of that machine, developed due to demand for more sync options. It is packaged in a utilitarian black box -- we are talking 'home brew' -- and its name isn't even screened on the top. Don't be alarmed by the rattling when you shake it -- it's just the solder tags on the unit's many 5-pin DIN sockets. Apart from the expected MIDI input, there are eight parallel MIDI Outs on the front, with a DIN sync output and a quarter-inch jack socket Sync Out at the rear. The power supply is internal (hooray!), although there is no power switch.

The last feature on this sparsely equipped product is a small, 16-way switch, accessed through a hole in the bottom, which, with a small screwdriver, selects various sync modes. This will probably only ever have to be adjusted once, but even so the choice and location of switch are a little bizarre. However, cost and ease of assembly may be behind the choice: a look at the tidy circuit board reveals that the switch is PCB-mounted, with access only possible by putting a hole in the box. The Sync switch offers the following options:

• Positions 0-7 select a preset sync division. This includes a 'no division' option that outputs 24 pulses per quarter note for driving a TR808, TB303 and various other pre-MIDI sequencers and drum machines via the 5-pin DIN socket. Also available are various sub-divisions (eighth note, eighth note triplet, 16th note, and so on) of the main pulse, for driving the arpeggiator/sequencer on instruments such as Roland's SH101 and Juno 6.

• Positions 8, 9, A and B select Control Mode; they assign the unit to receive on MIDI channel 1, 3, 8 or 16 (a little limited perhaps), and allow program changes to select the required sub-division. The general formula is:

24 divided by (program change + 1) = pulses per quarter note

For example, choose a program change of 5, and the result is four pulses per quarter note (16th notes); a program change of 47 provides one pulse every two quarter notes, and so on.

• Positions C, D and E select Direct Mode on MIDI channels 1, 8 or 16, which is even more flexible. Here, a clock pulse occurs every time you play middle C (Note 60), so complex rhythmic patterns can be programmed into your sequencer. A second sync pulse (for a second synth!) is provided by playing the next D (Note 62), although this is only available by using an optional DIN to 2-jack adaptor cable. The last position is for "future developments."

The sync options are flexible and comprehensive, but there are gaps. Some instruments use higher sync rates than 24ppqn (Oberheim's DSX sequencer and Roland's CR78, for example), and support for these instruments is beyond the Clock II Sync. MIDI's resolution is 24ppqn, so providing pulses at 24ppqn or less is easy; interpolating higher sync rates is more complicated, but may be offered in a future product.

The Clock II Sync may lack style, but does its job simply at an attractive price -- a price which includes an eight-way MIDI Thru box -- what a deal! Derek Johnson

info
£ Clock II Sync £89.99 inc VAT and UK postage.

A Big Time Productions, PO Box 520, Burslem, Stoke On Trent, Staffs ST6 5UR.

T 0782 810611.

Story By: Sound on Sound Magazine

Web Link: www.soundonsound.com/sos/1994_articles/may94/widgets.html

Email Link: jason@pureenergymultimedia.com

Date : 25-05-1994