Voice Recording and ADSL

June 20, 2004 10:24 AM

Three (well, five, really) short technical questions about voice recording and ADSL Internet connections in Australia [included inside].

My friend the NYC voiceover guy is relocating to Sydney, Australia. He is asking everyone he knows (and I have no idea of the answers):
1) What’s the difference between ADSL (the Australian standard, apparently) and DSL?
2) Is ADSL (available there at speeds of 256/64K, 512/128K, or 1.5/256K) faster than a cable modem?
3) More specifically, can he use two ADSL phone lines for remote recording with his new Telos Zephyr Extreme box, as opposed to two ISDN lines?

My own questions, after looking into this a bit for him, and getting confused:
1) Is DSL the same as SDSL?
2) How fast is a cable modem hookup in a reasonably large city, anyway?

posted by LeLiLo to computers & internet (7 comments total)

The A in ADSL stands for aysmetric, meaning that your upload is not the same as your download. My cable modem is 1.5/256k. Can't help with the other questions, I'm afraid.
posted by Orange Goblin at 10:35 AM on June 20, 2004

Here's my two cents' worth:

1) SDSL stands for Symmetrical DSL, i.e. the upload and download speeds are the same. So SDSL is not the same as ADSL (where upload speeds are generally much slower than download), but both SDSL and ADSL are forms of DSL.

2) I get as much as 4M bits download on my cable modem, which is generally faster than DSL. Cable speeds vary dramatically by provider and location, so his experience will almost certainly differ.

3) ADSL is not equivalent to ISDN, so you can't just use gear made for one with the other (at least in my experience). The Telos website has a feature chart that suggests that the "XStream" model has an ethernet interface that might possibly work over an ADSL connection.
posted by Zonker at 12:40 PM on June 20, 2004

As has been metioned, ADSL limits the upload speed to a maximum of 50% of the download speed. DSL is available in Australia, but only in limited areas and is is unbelievably expensive (last time I looked, it was around AUD1500 per month. DSL=SDSL.

The biggest problem with ISDN is that it is a pay-per-minute-connected service, but it is potentially more reliable and more suited for mission-critical applications where cost is less of an issue.

I see no reason why you could not link two ADSL services to increase the available bandwidth, although this would be expensive. What are the actual bandwidth needs up/down to do what he needs to do, as there may be another solution?

Broadband Choice is a good forum for investigating broadband options in Australia.
posted by dg at 3:57 PM on June 20, 2004

Thanks, all. dg, I'm not sure about the actual bandwidth needs, but I believe one problem is that he needs to upload quickly, whereas (as Zonker says) with ASDL it's the other way around (up slow, down quick).
posted by LeLiLo at 4:44 PM on June 20, 2004

Yes, that is the problem with ADSL - the relatively slow upload speeds, allegedly forced by Telstra's desire to corner the lion's share of the hosting/ISP market in Australia. Given that he is (I assume) only uploading audio, would the 256k upload speed of the 1.5M/256k plans be fast enough?
posted by dg at 5:07 PM on June 20, 2004

Two ISDN lines put together can transfer about 128k per second. This is actually the two data channels that make up a single ISDN connection, which I think is what this device uses. If it actually uses two seperate ISDN circuits (i.e. four data channels) then it provides up to 256k per second or so. Either way, I think that an ADSL connection should be fast enough (assuming, of course, that it works at all with his hardware).
posted by Zonker at 6:24 PM on June 20, 2004

Checking the Telos site again, there's a technical paper on ISDN vs. DSL that suggests that a DSL connection may not work too well. It's worth a read.
posted by Zonker at 7:05 PM on June 20, 2004