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Integrating Samplers & Your PC Via SCSI

Tips & Tricks By Martin Walker
Published October 1996

When Martin Walker decided it was time to buy a removable SCSI hard drive for his sampler, he fondly imagined that it would be a centralised storage solution for both samples and MIDI data from his PC, streamlining song organisation and making sample management easier. Enter reality...

When I bought an Akai sampler a couple of years ago, the salesperson told me to expect to need a removable hard drive within a couple of months. At the time, my last thought was spending more money! However, when I discovered that a single song using 8Mb of samples could fill up to five high‑density floppy disks, I began to rethink. The last thing you need if you're having a creative burst is several minutes loading time before you hear whether a different sample is more suitable in context. You want to audition it now!

When looking at the options for removable drives, I realised that the same drive could be used by my PC for more general use. The thought of editing and looping samples on a large computer monitor screen was enticing enough, but if I could also store the sample data for each song on the PC with the MIDI files, everything could be kept in one place. Centralised storage would ensure that a sample associated with one particular song would never be accidentally wiped. At the time, this dream seemed easy enough to achieve — the Akai S2800i had SCSI, the computer could be fitted with a SCSI interface card, so if I bought a SCSI removable hard drive, everything would talk to everything else. Wouldn't it?

How naive this all seems now...

True Lies

The main fly in the ointment is that hard disks need formatting by the device controlling them. Akai samplers format differently from PCs, so an Akai‑formatted cartridge cannot be read by the PC, and vice versa. This is because in order for data to be stored on the disk, a small separate area must be set aside to store the directory (the collection of filenames and location of each file on the disk). CD‑ROMs work in the same way, and this is partly why different versions exist for Akai, Roland, Emu, Ensoniq, Kurzweil, and so on. The other factor to bear in mind is that the program data will be different for each brand, with some parameters unique to each device.

Fortunately, in the last few years sampler manufacturers have made efforts to add cross‑compatibility to their machines, allowing them to read foreign programs and extract valid information, while discarding anything that would not make sense. However, the option to 'Read Akai‑Format Hard Disk' does not yet exist for computers.

It's easy enough to use the same removable drive for a computer and a sampler — just format two cartridges (one from each device) and use only the appropriate one — but unless you want to keep re‑plugging SCSI leads from one to the other, you need a way to connect all three devices. Continual swapping of data cables is never a good idea, and if SCSI devices are switched on at the time you may blow something.

The Terminator

SCSI devices are designed to be used in daisy‑chain fashion, with up to seven devices connected in one long line. To ensure proper operation, the device at each end of the chain must be terminated, while those in between must be left unterminated. An analogy often quoted is that the chain is like a length of string that has to be firmly anchored at both ends. A terminator plug will normally be supplied with each SCSI device, or an internal one may be present, which can be switched in and out as required. At one end of the chain, the computer is in control and should be terminated, while at the far end, the final device in the chain also has to be terminated

Once your samples are in a computer, you have access to a multitude of useful utilities that sampler manufacturers cannot provide.

Unfortunately, samplers also need to control the SCSI bus for their own purposes (see Figure 1 for connection details), and problems will occur if both the computer and the sampler try to take control of any SCSI device at the same time. As long as you're careful, things will be OK, but watch out for the following: during the boot‑up routine, any controlling SCSI device (in our case, the computer or sampler) will interrogate the SCSI buss to find any connected devices that are powered up — a sensible procedure. However, if your sampler is busy accessing the drive when you switch on your computer, the inevitable will happen — and it did to me. I lost 100Mb of samples in a few milliseconds when the PC took control of the drive during an Akai sample load and scrambled the data. No doubt the actual sample data was still intact, but the directory was corrupted, so a large group of samples just disappeared as far as the sampler was concerned. You'll only make this mistake once!

Once the computer has finished setting itself up, it will only access a SCSI drive when you specifically ask it to, so the above problem can only occur while everything is powering up. However, in my experience, on occasions the Akai also refused to read anything from the hard drive unless the PC was switched on as well — this sort of problem can occur because the PC end of the SCSI chain is only properly terminated when power is applied. The safest procedure is to switch on the SCSI drive first, then allow the computer to boot up completely. Finally, switch on the sampler, and wait for it to finish setting itself up before doing anything else.

SCSI devices are normally very reliable in use, but you may get occasional inexplicable errors during read and write operations. Using high‑quality (expensive) SCSI cables is the first step towards preventing data errors — never use cheaper parallel printer cables for SCSI use. The best cables have individual shielding for each connection within the cable, and mine are about half an inch thick and not very flexible. If you do have problems, the second thing any technical support person will ask is how long your cables are — anything over one metre in length may give unreliable results. A systematic approach is sometimes needed to track down problems — remove all items from the SCSI chain one by one (powering down and rebooting at each stage) to identify which device is causing the fault. Teething problems can be annoying, but once they're sorted out everything will normally stay very reliable.

The Floppy Route

I worked with this system for several months, until a project needed sampling on the Akai, but delivering in PC .WAV format. It seemed the ideal time to pursue my original goal of getting the computer and sampler directly connected, but the quickest way to get up and running proved to be by using the humble floppy disk. I had previously bought a copy of ReSample Professional, a versatile PC sample‑editing and conversion program which will also read Akai‑format floppy disks, as well as a selection of other formats, including those for models by General Music and Ensoniq. It also has an extremely good loop finder that can save a lot of editing time! (See SOS September '95 for a review.)

It proved easy enough to save samples onto an Akai floppy, pop them into the PC floppy drive, and read and save them in other formats using ReSample Professional. Kurzweil K2000/2500 owners are lucky in that their machines can read DOS‑formatted disks, and these can also obviously be read directly by a PC. Once samples were inside the PC, the lure of large‑screen editing again took hold.

Chill Out With MIDI Sample Dump

The floppy approach works, but it is a very convoluted procedure to have to go through for editing, when the process also has to be repeated in the reverse direction to get the edited samples back inside the sampler. What is needed is a direct connection between sampler and computer, and I decided to pursue the much‑maligned MIDI Sample Dump Standard (SDS). Yes, it is like watching paint dry (a single 180k sample will take about one minute to download), but it is a standard that is well documented and has been established for several years. I expected to find many PC programs that supported it. However, there are several (including Resample Pro) that will send dumps to a sampler, but no lower‑cost programs seem to be available that would work in the other direction. There are many synth editors which allow two‑way communication for editing and library storage, but sample dumps are very different beasts to SysEx dumps.

SampleVision for Windows (reviewed in SOS December 1995) sounded promising, but Turtle Beach have now discontinued it, and the only product that I could find that fitted the bill was Sonic Foundry's Sound Forge. This is a comprehensive sample editing package (see review in the May 1996 issue of SOS) that supports MIDI SDS, and has recently had its UK price reduced, which is a bit of a bonus.

Using SDS is easy once you've set up the correct options for your particular sampler — the help file for Sound Forge is particularly good, and offers specific advice for connecting to various samplers, including Akai models. Transmitting samples from the program to the sampler worked first time, but I did have problems receiving dumps from the Akai if they were more than a few hundred bytes long, since the program hung until the sampler had finished sending the rest of the data. Sonic Foundry told me that the problem was probably caused by a combination of a slow PC (mine is a VL‑BUS 486DX33) and an unbuffered MIDI interface (which most are), since receiving constant packets of SDS data can cause so many interrupts that a slow PC will grind to a halt. When transmitting from the PC, it's the sampler that takes the overhead, so in this direction things are easier for the PC.

The SCSI Connection

Throughout daily use for several weeks, Sound Forge was a pleasure to use, and my only big disappointment was that Akai samplers cannot use its much higher speed SCSI sample dump facilities. The recent SCSI MIDI Device Interface standard (SMDI) defines a suitable standard for two‑way high‑speed sample dumps over the SCSI buss; devices supporting this include the Kurzweil K2000/2500 series, and the Peavey SP sampling module. A computer simply has no way of knowing what data is present in a sampler unless it asks the correct questions, and Akai samplers use their own unique set of commands, which is useful for transferring samples between two Akai samplers but not much else. Because SMDI is not implemented by Akai, extra code would need to be written by Sonic Foundry to support only Akai samplers — they're currently working towards this, and will hopefully include it in a future release.

To address this limitation, Akai themselves have produced a Mac program called MESA (Modular Editing System by Akai), which has been written from the ground up as a large‑screen version of the internal Akai sample and program editing system. Any parameter that can be edited within the Akai sampler on its own little LCD screen has an equivalent control on the computer screen, and both sample and program data can be loaded and saved to the onboard computer hard disk. A PC version is currently under development in this country by AL Digital, the company who, among many other things, have distributed the Akai sound library during the last few years. This is welcome news indeed for PC‑owning Akai users, and means there's an end in sight to peering into that little LCD screen!

Computer Aided Design

All of this may seem like a lot of effort, simply to gain a large screen and centralised storage facilities, but once your samples are in a computer, you have access to a multitude of useful utilities that sampler manufacturers cannot provide in their own internal operating systems, either due to space limitations or lack of time. At a basic level, it's far easier to organise a large number of samples when viewing the contents on a computer monitor — not only can you see dozens of filenames simultaneously and sort them by name, but each will have a date stamp created when the file was saved. How many times have you found two samples with identical names on a hard disk, with no way of remembering which one had all those tweaks made to it? On a sampler the only way to find out is to load each in turn and listen — a daunting task if only one multisample of a dozen associated with that particular sound has had its loop point tweaked. With a computer, even if two samples have identical date stamps, you can use file‑compare utilities which allow you to see whether identically named sounds actually contain different data. Using a sampler alone, it's normally easier just to leave these possible duplicates where they are than to tidy things up.

Another frustration with many samplers is their insistence that you divide a hard disk into partitions (see 'Divide and Conquer' box). Even though there's still plenty of empty space left on the hard disk, if one partition becomes full, you have to select another partition to use. If, like me, you try to organise a large number of samples into suitably‑named directories, to make looking for a particular type of sound easier, this task becomes increasingly difficult as the disk fills up. Once your samples are in the computer, even with partitions it's quick and easy to do large‑scale moves and copies — unlike the sampler, where the only way to move sounds is to load them into sampler memory, delete the original on disk, and save them to a different location. In fact, once your samples are in your computer, you have total freedom from any sampler partition restrictions.

Defragmentation and disk‑scanning utilities also allow you to perform regular housekeeping on your hard disk, speeding up access to data when the disk begins to get disorganised, and spotting any disk errors before problems get too serious.

Total Recall

Unless it turns out that there are unseen disadvantages, as soon as the PC MESA software appears I intend to use it to store all my Akai samples in the computer. In storage terms, it will only mean that the data ends up on an identical Syquest cartridge, but formatted by the PC rather than the Akai. However, given all of the above advantages it would seem silly to do otherwise.

But the biggest advantage of all may be that if any of my sample data ever gets corrupted again, I can attempt to rescue it with one of the many salvage and recovery programs available for the PC. The last time it happened with my sampler, the technical support staff could only offer tea and sympathy.

Getting Help From The Internet

While writing this feature I had problems with one of my Syquest cartridges holding PC data. I bought my 270Mb drive in a desktop unit badged by another company, and it arrived with no PC utility programs at all — just a Mac disk and the wrong cable (some things never change). Lack of suitable utilities is a common problem for many people if they buy one of the rack‑mounting hard drive systems offered by specialist dealers. However, while browsing the Internet, I discovered that Syquest themselves provide numerous utilities for use with their drives, that can be downloaded free of charge. By reformatting the cartridge using their utility rather than the generic one provided with Windows 95, I solved the problem. FAQs (Frequently Asked Questions) are also provided by many manufacturers elsewhere on the net; these can solve problems without long and involved telephone calls to voice support lines, which often seem to have one operator per 50 enquiries.

Divide And Conquer

Back in the dim and distant past, when hard disks of 20Mb were considered practically unfillable by mere mortals, PC operating systems set an arbitrary limit of 32Mb as the maximum hard disk size. As bigger disks came along, the concept of partitions allowed a larger drive to be split into several sections, each treated by the computer as a separate device. A 90Mb disk had to be viewed as a minimum of three sections. These restrictions have long since been removed, allowing partition sizes upwards of 1Gb, which are vital for hard disk recording.

You may wonder why many samplers still insist that you divide your hard drive into partitions rather than use one large area. One valid reason, which anyone struggling with a hard disk recording system will know, is that regular defragmentation can make the difference between glitch‑free recording and a choppy mess. This is because files newly written to disk are slotted into whatever empty space is available. A single sample may end up split into several sections, each filling a convenient 'hole' on the disk, and writing these sections to disk or loading them back into memory will take longer than a single chunk. With the onset of hard disk recording options for samplers, a separate partition reserved for this function ensures that the recording process is not trying to work around hundreds of small program files already on disk. This will speed up disk reads and writes, and help ensure optimum results during recording. The ideal solution, of course, is to use an entirely separate drive for recording.

Contacts

MESA for PC: £TBA

www.akai.com

ReSample Professional: £99

www.etcetera.co.uk

Sound Forge: £299.95

www.sfoundry.com

Removable drives

syquest.com