Glyph Technologies SCSI

The Glyph 2U Custom Combo, seen here with a 1‑into‑3 SCSI switcher in the left bay and a 4.5Gb Seagate Cheetah hard drive in the right.

Musicians can have a tricky time choosing suitable hard drives for audio recording, but Glyph claim their range is ready‑optimised for music applications. Martin Walker puts their assertion to the test...

Although Glyph are not yet widely known in the UK, in the US their AV (Audio Visual) hard drives have apparently taken a 70 percent share of the music‑sector market, and are routinely recommended by US Digidesign reps for hard disk recording. Apart from hard drives, the Glyph range also encompasses CD‑ROM and CD‑R drives, SCSI switchers and cables. Those of you who gig or tour, especially, will be pleased to hear that all feature auto‑sensing power supplies, which will work with any voltage between 90 and 260V AC (rack units) and 110 to 230V AC (tabletop units).

Since the range is primarily intended for audio work, it has been extensively tested with many systems. Drives are available that are compatible with Digidesign's Pro Tools 3, 4, Powermix, 442, Session 8 and Audiomedia — both Nubus and PCI. Glyph also provide compatible hard drives for many other digital audio workstations and samplers, including those from Akai, Emu, Roland, Spectral, and SADiE.

I had a selection of Glyph drives to look at, including a tabletop CD‑ROM drive and what they call a Custom Combo — a 2U‑high rackmounting enclosure with a choice of any two devices mounted side by side. 1U‑high rackmounting Custom Combos are also available, which can hold one or two fixed drives.

Custom Combo

The GCD1600ST CD‑ROM drive comes complete with a pair of 50‑way Centronics SCSI sockets and is supplied with CD‑ROM Toolkit software.

The 2U Custom Combo range can hold any two drives, and for maximum flexibility all hard drives can be supplied in Kingston hot‑swap trays, complete with handles and a set of keys for the locking mechanism. The cases are built to last, with rugged metal construction, and feature 'SuspenShock' mounting for the drives.

There's a large range of SCSI drives to choose from, including models from Seagate and Quantum. Standard hard drives are available from 1Gb to 9Gb (fixed or removable). Iomega Jaz drives, Seagate Travan 4Gb backup tape units, DAT backup drives, and a selection of CD‑ROM and CD‑R drives are also offered.

Mine came with a 1‑into‑3 SCSI switcher on the left (model GSS310) and an AV‑tweaked hot‑swappable 4.5Gb Seagate Cheetah hard drive on the right. This business of tweaking drives may sound suspicious, but it is definitely based on fact rather than fiction. Just as computers set up for mainstream applications don't necessarily suit audio recording and may benefit from optimisation, hard drives can also be adjusted to give better performance when reading and writing huge files (rather than the more typical large numbers of small files resulting from most other applications). The result is a drive that performs better for hard disk audio, but with a downgraded performance for more general activities.

Any drive that's guaranteed to work with a range of samplers can save a huge amount of wasted time.

The Cheetah drive is an Ultra Wide SCSI device (Adaptec's 2940UW host adaptor is normally recommended for PC use), and has an average seek time of about 8mS, a peak transfer rate of up to 40Mb/second, and an average latency of 2.99mS. The latency figure is so low because the spindle speed is a high 10,000rpm (revolutions per minute).

Many of the fastest PCs have used this drive recently, but it can be noisy and generate heat, because of its high rotational speed. After I had plumbed in the half‑inch‑thick SCSI cables to connect the drive to my PC, powering up did produce a noticeable increase in the background noise of the studio, mainly from the drive itself. Of course, once the drive was mounted in a rack this noise would decrease a bit, but it's something to bear in mind when siting your drives — especially since the faster the drive, the shorter the maximum SCSI cable length tends to be for reliable operation.

Performance of the drive was excellent, as expected, although I obviously wasn't able to verify any improvement as a result of the drive tweaks, since I had no access to the 'untweaked' version. I did measure a sustained transfer speed of 9.3Mb/second with the Adaptec SCSIBench utility, but this is so dependent on the files being written that it is difficult to provide accurate figures. When buying a drive like this, the best bet is always to try it in conjunction with the software that you're hoping to use it with.

Another aspect of drive performance that is difficult to quantify is reliability. Part of the secret of a long life with any drive is cushioning it from mechanical and thermal shock. The Glyph rack casing is good in these respects, and some users have apparently bought Glyph products because they already have a proven reliability record, carrying on for years and years where other units fail.

Sharing A Switch

The rear of the Custom Combo.

The other half of the supplied rack, as mentioned earlier, contained a 3‑into‑1 SCSI switcher. These are proving extremely popular, for obvious reasons. You might have two samplers, a sampler and a computer, or two computers, and normally (unless you brave the rigours of attempting to set up a SCSI chain with two hosts — not recommended) the only way to share any of these devices is to power everything down, reconnect your cables, and power up again.

The SCSI switcher overcomes those frustrations. There are 2‑into‑1 and 3‑into‑1 versions available: the user connects one SCSI chain of up to seven devices on the output and can then hot‑swap between two or three hosts. All the sockets are of the 50‑way Centronics type, so you're restricted to narrow SCSI devices, but 68‑pin Wide SCSI versions are expected soon.

Operation is simplicity itself, with a 2‑ or 3‑way rotary switch and a 7‑segment readout of its current position. Since the switching is electronic, you can safely switch the SCSI buss while everything is powered up, without worrying about risking any data during the changeover.

Tabletop CD‑ROM Drive

As anyone who has tried it knows, getting SCSI CD‑ROM drives to work reliably with samplers can be an absolute pain, and any drive that's guaranteed to work with a range of samplers can save a huge amount of wasted time. Glyph select and test their drives "to work with the broadest range of samplers as well as offering the highest performance in a computer‑based, multimedia environment."

The GCD1600ST Glyph drive I tested came in a metal tabletop casing, with the rear panel featuring a pair of 50‑way Centronics SCSI sockets, push‑button ID number selector, and a pair of gold‑plated phono audio outputs. It comes bundled with the CD‑ROM Toolkit from FWB (for Mac users only).

I fully expected this drive to work first time with my Akai sampler, and I wasn't disappointed, but what I wasn't expecting was its speed — this is the fastest I have ever seen samples load from any CD‑ROM drive. When I reconnected the drive to my PC, the PC reported it as a Toshiba XM‑3801TA, which turned out to be a 15x speed device (theoretically capable of maximum sustained transfer speeds of 2.25Mb/second). Although samplers are unlikely to support this top speed, I measured values up to about 2Mb/second when the drive was used with my PC, and an average seek time of 76mS, which is very respectable.

Unfortunately, although the drive is capable of digital audio extraction, neither Wavelab nor Sound Forge supported it, so I was unable to confirm this aspect. The primary function for which the CD‑ROM drives are intended is sampler support, but the CD‑R drives in this range have been tested for compatibility with all the major packages on both Mac and PC. One neat feature for audio use is that the cooling fan only comes on when the drive is active, so although you get the normal fan 'whoosh' when loading files, total silence returns within a few seconds of the load being finished.

Conclusion

The Glyph range is professional through and through, and if you want the best performance from external SCSI drives they seem to have products to suit most requirements. There are several other ranges with equally professional specs, notably from Rorke Data and Dynatek, but if you buy elsewhere you may not get the AV‑tweaked performance of the Glyph hard drives.

...this is the fastest I have ever seen samples load from any CD‑ROM drive.

The best never comes cheap, and if you're building a budget system you will undoubtedly find cheaper parts elsewhere. This particular Custom Combo is especially expensive, as it features the hot‑swappable bay; it is possible to get the same performance in a fixed unit for less money. However, the Glyph systems are at least complete: in some systems, cabling can be a significant hidden extra. SCSI cables are never cheap, but Glyph supply everything you need with their drives — mains cables, SCSI cables, and terminators, worth between £30 and £100 by themselves (SCSI‑3 terminators typically cost £60).

Global Distribution, Glyph's UK distributors, have good knowledge of SCSI and its problems, and understand the issues that concern musicians. Although they distribute to dealers, they are also prepared to help end users with any SCSI problems that occur.

Most of the drives come with a five‑year guarantee, and (subject to certain checks) if the worst happens and a fault develops in the first year, a 24‑hour replacement warranty is provided. Support like this implies that Glyph are confident about the reliability of their products. If your livelihood is dependent on stable equipment that doesn't let you down during an important session, the Glyph range should certainly be on your shortlist.