Is Single-ended SCSI OK?

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shaneperc
Posts: 11
Joined: Wed Sep 25, 2002 23:05
Location: Orlando, Florida

Is Single-ended SCSI OK?

Postby shaneperc » Sun Oct 20, 2002 05:22

Hello,
On a spur-o-the-moment buy on eBay, I bought some Storcase (Kingston) removeable drive bays. I saw that they had 68 pin connectors, and assumed they were for LVD drives. However, the frame/carrier unit itself is a single-ended device, which means if I use them, my entire scsi bus will run in single-ended mode, which has a maximum throughput of 40MB/second.

I just wanted to find out (from all you scsi experts out there) if it's possible (or advisable) to record in 96/88.2Khz using a Single-ended bus, or if I should just admit defeat and put those drive cases back on eBay where I found them!

Thanks very much for your help!

Shane

Pyromanic
Posts: 478
Joined: Wed May 22, 2002 18:31
Location: Germany, Lindlar
Contact:

use headroom...

Postby Pyromanic » Mon Oct 21, 2002 07:30

Hi,
you should think about it like in the Audio section, don´t mess up your headroom of LVD (160MB/s).... You not only bond the Bays on 40MB/s, you limit the whole bus to this speed. That means if any drives have to correspond on the same bus at the same time or even wanting to do a burst-read while recording, they have to share this 40MB.....
Normally this should be enough for doing your recording, but I would not limit the system, just to have a changeable device-slot.
best regards

Pyromanic

shaneperc
Posts: 11
Joined: Wed Sep 25, 2002 23:05
Location: Orlando, Florida

Postby shaneperc » Wed Oct 23, 2002 04:10

Thanks for the input, Pyro.
I went nuts and added up the throughput needed for a full 24 tracks of 96khz, 32 bit worklength files, bidirectional, and it came out to just below 150Mb/sec, and that's without any preamble or dodads added on. I'll probably never need that much firepower, but I feel better being safer than sorrier.

Stephan Cahen
Posts: 4
Joined: Sun Nov 10, 2002 22:33

Postby Stephan Cahen » Sun Nov 10, 2002 22:38

Shane,

if those carriers are DE100 SWu2, which I suppose they are, you can "upgrade" them easily by attaching a repeater board made by Kingston. Model # is DX1/200-u2/RH.

Not inexpensive, though...
Check @ www.storcase.com

Regrds,
Stephan Cahen
sempre la musica!

shaneperc
Posts: 11
Joined: Wed Sep 25, 2002 23:05
Location: Orlando, Florida

Postby shaneperc » Mon Nov 11, 2002 05:19

Stephan,
Thanks for the info. I didn't know that the repeater board could change the carrier to LVD.

Muchas Gracias

Stephan Cahen
Posts: 4
Joined: Sun Nov 10, 2002 22:33

Postby Stephan Cahen » Mon Nov 11, 2002 09:55

De nada,

for those of you that don`t want to search the whole Storcase site, here`s the exact link:

http://www.storcase.com/tools/benefit.asp

Best wishes,
Stephan Cahen

sempre la musica!

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phaseboy
Posts: 504
Joined: Thu Nov 21, 2002 23:41
Location: London, UK
Contact:

NO that's not true.

Postby phaseboy » Fri Nov 22, 2002 08:44

Sorry but that's incorrect. The hot-swap card does not make an SE frame LVD. And that's not what the above posted link implies. Kingston recommends using hot-swap card's on all LVD enclosures (Ultra2 and Ultra160) to improve performance and compatibility with multiple devices - not to turn them into LVD devices.

You must be very careful when combining different kingston carriers and receivers. They should be backwards compatible but that's not always the case. EG: The LVD receivers will work well with both SE and LVD carriers. However the SE receivers will more often than not cause serious problems when used with LCD carriers.

I've logged way to many hours dealing with this and way too many hours on the phone with kingston and seagate. Ultimately it has caused me to switch to fibre channel for large projects - which is much more stable. If you want good performance and the ability to "toss" any drive in you kingston receiver you should have an Ultra160 LVD/SE controller (or higher) and Ultra 160 LVD receivers with hot-swap cards. If you use SE receivers just make certain that you don't put LCD carriers in them - it will bite you at the worst moment.

Sorry to be so long-winded. Just lost too many hours of my life dealing with this...

Best Regards.

Mark Willsher

PS: Unless I'm mistaken Ultra2 is always LVD