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Tutkaillessani RME:n uuden FireFace800:n manuaalia silmiini sattui mielenkiitoista asiaa firewire-väyläisistä äänikorteista ja nimenomaan verrattuna perinteisempiin PCI- ja PCMCIA-ratkaisuihin. Samassa manuaalissa on muutakin mielenkiintoista taustatietoa äänikortteihin liittyen eli kannattaa käydä lataamassa se pdf:nä www.rme-audio.com:sta .
 
"FireWire Audio
 
FireWire audio is in several ways different from RME's earlier PCI audio interfaces. First of all,
our cards have a PCI interface which has been developed by RME and optimized for audio.
FireWire on the other hand, uses OHCI-compatible controllers that have not been optimized for
audio, no matter from which manufacturer they are. Our PCI data transmission is per channel,
while FireWire is working interleaved, i.e. it transmits all channels simultaneously. With the
Hammerfall, drop-outs thus occur only on the last channels, which is not always noticeable,
while a drop-out with FireWire always concerns all channels and is thus perceived much
clearer. Apart from this, RME's PCI audio cards establish a direct connection with the applica-tion
under ASIO (Zero CPU load), which is principally not possible with FireWire, because
communication has to be established by the operating system's FireWire driver. Compared to
our PCI cards, the FireWire subsystem creates an additional CPU load at lower latencies.
To put it short: We cannot recommmend using three FireFaces at full load (84 channels) with-out
running into a moral conflict. There are considerably higher performing solutions available
for these purposes, like the HDSP MADI in combination with the ADI-648. The advantage of
FireWire is in its portability and simple connection to various computers, hot-plugging and
more.
One FireFice 800 can achieve a performance similar to a PCI card with an optimal PC. An
'optimal' PC has an undisturbed PCI bus. Intel's motherboard D875PBZ e.g., has network,
PATA and SATA connected directly to the chipset. No matter what you do with the computer,
FireWire audio is not being disturbed. The same holds true for the ASUS P4C800, as long as
you leave the additional SATA controller (connected to the PCI bus) unused.
Due to insufficient buffering within FireWire controllers, single peak loads on the PCI bus can
already cause loss of one or more data packets. This is independent of the manufacturer and
no RME problem. To the contrary, the FireFace 800 has a unique data checking, which allows
to continue playback in spite of drop-outs. Other devices on the other hand stop playback,
cause crashes or distorted playback, or require a manual driver reset."