| wire wrote on Fri, 25 March 2005 01:31 |
Those will NOT work. There was just a thread about this on the Tape Op board.
The adapters are not signal converters. They just take a AES XLR 110 ohm and change it to BNC 75 ohm so you can run AES over coax.
The signal needs to be converted from one standard to the other. With a box such as the FCN-1 seen here http://digido.com/portal/pmodule_id=11/pmdmode=fullscreen/pa geadder_page_id=16/
There are other boxes as well.
|
Actually, these "passive" converters may very well do the job. There are not many FCN-1's left in stock... I only sell about one a year, especially since these days I try to discourage people from buying them UNLESS they have a specific problem that only the FCN-1 or a similar format converter can handle.
First of all, it's important to separate the "protocol" from the cable issue. It's possible to send a consumer protocol over a "professional" line, and vice versa. It's possible to send a professional protocol over an optical or Toslink line as well. If the receving device (tape recorder or DAW) ignores the channel status bits coming in, then it won't matter if it's coming in on an XLR, RCA, or lightpipe connector.
So, in that respect, if you aren't feeding a DAT machine, and you're not worried about jitter (which is not an issue in digital transfers), and you only have a short cable, then a simple adapter between RCA and XLR will do the trick. Even though the impedances are not matched or the levels are not officially "correct". The reason is that for many years now, all the typical receivers can receive voltages from as low as 200 mv to as high in some cases as 7 volts, with no trouble.
There are still some features that you may need and won't get with a simple passive adapter:
1) Optimum signal transfer from matched impedance and proper levels over a long line.
2) Distribution amplifier features, so you can feed several loads of different types at once.
Unfortunately, the FCN-1 also contains a PLL so the jitter on its output may be greater than what's coming in, but that depends on how high the source jitter is, as there is some jitter reduction capability in every PLL.
In cases where people are trying to feed SPDIF over a long line, or an AES long line into an SPDIF receiver with the most optimum signal transfer and fewest reflections, I usually recommend a transformer such as a Neutrik or Canare, or in some cases a simple resistor network will suffice.
The number of receiving devices that actually discriminate between the professional and consumer status bits are very very few nowadays, mostly old DAT machines.
