While the Saffire PRO 40 is billed as a computer audio interface and the OctoPre MkII Dynamic is marketed as an 8-channel mic preamp/converter with compressors, they share a lot of the same elements and capabilities, such as the mic preamp circuits and metering panel. Although the units can be purchased and employed individually, OctoPre can also be connected to the Saffire to expand I/O count and capability. I'll first cover the OctoPre. Unless specified otherwise, assume that what is said about the OctoPre applies to the Saffire. Also, for more on Saffire, you can read my review of the Saffire PRO 24 DSP in Tape Op #80. As usual, I won't give you details on all features, so please check the very informative Focusrite website for complete specifications as well as the particulars on bundled software.
I liked the OctoPre MkII Dynamic as soon as I pulled it out of the box. It's heavy and feels solid. The front panel has light-gray lettering and blue marks on a black surface, so it is relatively easy to read in dim light. The knobs are smooth flowing and offer good physical resistance, so you won't have to worry about changing gain by brushing against a knob. Included is a word clock input for synching to a master clock, and the unit features JetPLL, a well-respected phase-locked loop system for suppressing jitter. It'll do 24bit, 96 kHz across all eight channels with dual SMUX'ed ADAT outputs. It may be marketed to project studios, but it looks pretty professional. The eight preamps are of a well-reputed design, and two of them double as instrument inputs. Plus, there's a compressor on every channel. It also includes eight channels of D/A conversion with balanced outputs.
The OctoPre hooked right up and is a perfect match for my stand-alone Alesis HR24XR hard disk recorder. As would be expected, it also worked flawlessly connected to the Saffire as well as to my RME and PreSonus audio interfaces. Because all converters exhibit latency, I wanted to measure how much additional latency the OctoPre adds when it's chained to the digital inputs of an audio interface in this manner. With the OctoPre hooked up to the ADAT input of the Saffire, I ran duplicate signals to both and recorded both channels to DAW. The OctoPre added five samples of delay at 44.1 kHz - worth noting, but it's easy enough to compensate in situations where it matters.
For audio quality testing, I first set up a high-output condenser about 6'' from a guitar amp and played a drum loop and measured the sound pressure - about 105 dB SPL. With the -15 dB pad engaged on the mic, I couldn't even get close to overloading the Focusrite preamp, and I never engaged the pad on the preamp. It can handle loud. I then set up my old ribbon mics, with their amazingly weak output. I did not expect a good match because the Focusrite preamp is rated at 55 dB maximum gain. However, the preamp turned out to be by far the best for my old ribbons, beating out the preamp I've been using by a wide margin, which is suspiciously rated at 70 dB gain, and yielding plenty of signal and an unbelievable absence of noise. I've always expected a certain amount of hiss when using these mics; I could barely hear any hiss with the Focusrite preamp set to maximum gain. The ribbons also produced more low-end than with the other preamp. The difference between the real world results and the spec sheets must be evidence of Focusrite adhering to the AES17 testing specification, which they advertise and encourage on their web site. Speaking of AES17, if a datasheet does not publish a standard by which the specifications were derived, ignore it. I have personally witnessed the reworking of spec sheets to make them look better (over my dead body) to the uninitiated, so be warned, it does happen. Three cheers to Focusrite for doing it correctly and saying so.
These preamps are JFET-based, and to my amazement and delight, they are wired to soft-saturate. Hitting them hard with condenser-mic'ed vocals gave a pleasant sounding distortion, the amount of which could be dialed in with gain. With the tone knob all the way down on the passive bridge pickup of a guitar, overdriving the Focusrite preamps sounded spectacular! It's a super-creamy fuzz tone that you'd want in a pedal - I'm not kidding!
I really like the OctoPre's compressors, but in this context, I wish they were limiters, because I'd be more likely to use eight limiters in a tracking situation. As it is, they do 2:1 or 4:1 ratios, and the compression knob controls the threshold. It works like an LA3A (Tape Op #49) but with automatic make-up gain. They are smooth and creamy on the right sources, especially vocals, but they get a pinchy kind of sound when pushed hard. They're generally smooth enough that I initially thought they were optical, but in reality they are a VCA design loosely based on the Focusrite RED 3. It's up to you whether you need eight compressors or not. If you consider though, that this unit is only a couple hundred dollars more than the non-Dynamic OctoPre MkII, which has neither the compressors nor the D/A conversion, the compressors are a bargain. Where else could you get eight quality compressors and an eight-channel DAC for $200?
One more thing worth noting, the ADAT outputs are duplicated when operating at 44.1 or 48 kHz, as well as being duplicated on the analog outs. This could come in handy if you're feeding multiple devices simultaneously, or even if you often find yourself switching between one downstream device to another.
The Saffire PRO 40 has the same preamps as the OctoPre MkII, the same JetPLL, the same instrument inputs, and the same 8x5 metering panel, but it is firstly a FireWire audio interface with MIDI. (But it does store its routing state when disconnected from its FireWire host, so it can operate standalone.)
I first tested the performance of the Saffire's audio driver in respect to the output latency of a software instrument. With a piano patch, I was almost able to do 32 samples on my legacy Mac G5 with a heavy-handed part - just few clicks here and there - but things fell apart into an atonal aliasing anthem when I hit the sustain pedal. I had to move up to 128 samples for clean audio, but I'm estimating the unit can handle 32 samples with a new computer.
For testing MIDI jitter, I like to record a sample of a hi-hat from a keyboard, cut that to quantized 16th notes, and put that next to a MIDI track playing 16th notes to the same sample (while compensating for the keyboard's latency), then listen for flamming and flanging. There was no comparison between the Saffire and my MOTU MIDI Timepiece AV - sorry, the MOTU is markedly tighter. If you're just inputting and quantizing, the Saffire would be fine, but if you're the type that plays into a double-tempo sequence to get more MIDI clock resolution, the Saffire is not recommended for MIDI. It doesn't even have MIDI activity lights anyway, which was frustrating.
For a CPU-capacity test, I compared the Saffire to a PreSonus FireStudio (Tape Op #63), on the Mac G5 running PreSonus Studio One Pro (#76). I could run four more instances of the PreSonus Compressor plug-in while using the Saffire - 47 versus 43 at 24bit, 44.1 kHz.
The software control panel and digital mixing/routing interface that controls the internal, zero-latency, matrix mixer of the Saffire is well done. You can route any input to any output in a fairly intuitive way. I am very experienced with RME and PreSonus versions of the same concept, and overall, I like the Focusrite version - with one huge exception: it's the only one without output meters. The mixer has two "loopback" inputs to which you can route the outputs of other applications running on your computer, similar to what you can do with the free Soundflower software from Cycling '74. Speaking of free software, the Saffire PRO 40 comes with a pretty generous software bundle which includes Ableton Live Lite, Novation Bass Station, and 1 GB+ of royalty-free Loopmasters samples.
I love that the Saffire has two headphone amps, each with its own mix from the Saffire software. This is a worthy differentiator from most other interfaces, and it will save many customers from needing to buy a dedicated headphone amp to implement a different monitoring mix from one supplied by a built-in headphone jack. It also has dedicated monitor outputs with an anti-thump feature when powering up or down. The front-panel volume knob can also be assigned to multiple outputs (e.g., for a surround mix), which is a cool touch I haven't seen before. Mute and dim switches are also included - nice.
In operation, the OctoPre MkII Dynamic and the Saffire PRO 40 worked well, and I never had any real trouble with either of them. Because of their overall sound quality, performance, and economy, I can easily recommend them if their features meet your needs. In fact, I would buy either of these units for the preamps alone. (OctoPre MkII Dynamic, $699 street; Saffire PRO 40 $499; www.focusrite.com)