Fostex 812 Recording & 2016 Line Mixers
Article from Sound On Sound, April 1990
Best known for their tape recorders and cassette-based multitrackers, this new generation of mixers from Fostex look like they will make more than a few converts. Dave Lockwood checks them out.
The 812 is essentially a 12 input desk, routing to eight subgroups/tape sends, but with an in-line tape monitor section. This is actually a slightly unusual combination for the in-line topography conventionally dispenses with an actual group fader, whilst the normal split console generally locates its dedicated tape monitors within the outputs rather than the inputs. However, the arrangement chosen has, I presume, been selected for its ability to offer the maximum possible number of additional inputs, as there are 12 in-line monitors as opposed to only eight groups.
The desk, measuring some 26" by 21" by 2" deep, rising to 7" at the rear, is of a semi-modular construction with input modules carrying pairs of channels, with paired groups and separate master and meter sections. The metering occupies a wedge-shaped housing which projects out of the mixer surface giving good visibility combined with a relatively low profile. Eight 25-segment LED ladders, changing from yellow to red at the nominal 0VU point, give a very bright and clear indication of bus levels. They have a very fast transient characteristic, with a temporary peak hold that can be switched in or out (although at about four seconds, the hold time is longer than I prefer). All connections, with the exception of the stereo headphone jack located on the front edge, are made to the rear panel with an appropriate assortment of ¼" jacks, XLRs, and phonos. The power supply is internal, with a fixed mains lead.
Input channel controls are sensibly colour coded, beginning with the channel gain control, designated Trim. There is no separate Mic/Line switching for there is sufficient gain range to accommodate signals from -60dBV (microphone level) to -10dBV, the nominal line level for this system. Gain setting is aided by a Peak LED which monitors the channel after the EQ section and thus helps to avoid equaliser overload as well as optimising channel headroom. A Tape/Input switch selects between an instrument source or the tape return signal, so repatching is not required for mixing, although the Trim control is inactive when the tape signal is selected - which is a shame, as a bit of extra gain is often valuable when mixing.
The 812's EQ offers a fixed shelving HF band with two 'sweep' or semi-parametric sections (I say 'semi-parametric' for there are no bandwidth or 'Q' controls needed to properly fulfil the designation parametric). Conspicuous by its absence is a dedicated, fixed bass control. The normal arrangement on budget systems is fixed HF and LF with either one or two sweep Mids. This gives rise to the debate as to where the LF should operate in relation to the lower end of the Mid sweep. With the LF fixed at, say, 60Hz there is invariably a gap until the parametric takes over at about 500Hz, yet it is precisely in this region that many signals often benefit most from some attention. If the LF is fixed higher, at say 100 or 150Hz, to be more usable in creative ways, then it is less effective in corrective applications, such as removing boominess or hum without affecting too much of the signal's basic tonality. The 812's lower parametric section offers 15dB of boost or cut between 60Hz and 1kHz, overlapping with the higher band, which runs from 400Hz to 6kHz, with the HF fixed at 10kHz. The fixed bandwidth is fairly narrow, I would guess at about 2/3rd octave, making it quite selective and more suited to cutting than boosting. All in all, an equaliser section to be taken a great deal more seriously than the simple two-band fixed EQs that tend to be used on compact mixers these days.
Versatility seems to have been the aim in all facets of the design of this Fostex desk and nowhere more than in the area of the auxiliary buses. There are effectively two dedicated postfade sends, one attached to the input channel and one available to be switched either to the input channel or the monitor path. The tape return section (the in-line monitor mix) is available as a third (stereo) aux, if not otherwise employed. If that sounds confusing, it isn't in practice and it is nothing like as complicated as the owner's manual makes it sound! Although actually quite good as manuals of Japanese origin go, this one still lapses into plenty of talk of ping-ponging and effectors, but I think loses a certain amount of clarity through burying the essential information in the wealth of detail needed to cover so many options. I am sure it would be clearer if each control's functions were dealt with one at a time. Still, there is a good explanation of some basic recording procedures and the generous use of pictures and diagrams will also help the inexperienced user.
Both effects sends, whether deriving signal from the input or tape return, are post-fade, so there is no facility for a 'cue' mix, independent of the control room monitor mix, to be fed to an external headphone foldback amp as would have been the conventional practice at one time. With present day working methods however, particularly in the home studio environment, it is a facility that will probably not be missed.
The third send, differentiated from the others by being designated Aux as opposed to Effect, will act as either another post-fade send, when its selector switch is in the Post position, or as the gain control of the tape monitor section, when selected to Tape. Effect Send 2 also has a function switch labelled 'Post/Tape', which determines whether it sends from the channel or the monitor path, although it might be better if this one were labelled 'Channel/Monitor', so that it is not only different from the other switch but more conventionally descriptive as well.
In addition to the Aux Gain there is a Pan control, acting either as the monitor mix pan or as a pan for the stereo effect send, according to the mode selected. If, like most people, you do not have any effects units with genuine stereo inputs, you can always use the stereo send as two monos using the Pan control to select between them or even send simultaneously to both, in any proportion.
Output selection is via four group assign switches, selecting pairs of groups, with the usual odd/even pan logic determining the actual destination. There are eight subgroups, but faders seven and eight double as the mix bus controls. This dual role causes no difficulty, for when track laying, group faders are often simply set to unity and then left alone (which is one of the reasons for dispensing with them in many in-line designs), whilst the monitor mix is independent of the master faders. During mixdown, when the master faders would of course be used either to trim the level to the master recorder or for a fade-out, you still have six subgroups left to play with, which should be more than enough. Subgrouped signals are sent on to the mix bus via Gain and Pan controls, labelled 'Group to L-R', which are, logically, omitted on buses seven and eight.
Both groups and inputs have a Solo facility, which is slightly unusual in being post-fader and post-EQ, but even more so in being stereo, so that the pan position is maintained. This goes part of the way to being the really useful 'solo-in-place' facility not normally found outside the realms of upmarket professional consoles, but the 'solo-safe' options on the effects returns needed to implement this are absent, and the sends are also defeated by soloing.
All inputs and outputs are completed by identical 100mm carbon track faders, which are pleasantly smooth in feel, offering about the right amount of physical resistance. Fader tops are ribbed and deeply concave, with no 'play' in the movement, making them easy to control accurately with pressure from one finger, which is certainly how I think faders should feel. Part of the plastic casing just below the faders provides a 'write strip' which you can mark with a chinagraph (wax) pencil effectively, although it doesn't rub-off as easily as some surfaces.
The remaining group of controls are the dedicated effects returns and the master switching functions. There are three identical stereo returns, each with Gain, Pan and Group assign switches to determine their destination. All eight groups can be accessed, so it is simple to record effects to tape when you want to, although normally one would just be using groups seven and eight to return signals directly to the mix bus. All three aux sends have master output level controls, with those of the effect sends being mono, whilst Aux 3 is stereo but on a single ganged pot.
Separate level controls are provided for the headphone socket and the master monitor mix, although the signal is derived from the same point. I found I could just about get enough level into a set of 600 Ohm phones, but it was marginal, and I didn't particularly like having to set the control flat-out. Lower impedance headphones do not suffer from this problem, but all the ones I regularly use, and prefer, tend to be high impedance (Sennheiser, Beyer etc). Four selector switches decide the monitor source, with a choice of Left/Right, Aux, or either of the effect sends. Obviously Left/Right would be selected for mixdown, but Aux would be the choice for utilising the channel aux sends as an independent monitor mix during tracklaying.
As this mix can be returned to any of the buses with a little patching, the facility can be used to generate 24 independently controlled inputs (not counting effects returns) on mixdown, eg. for synchronised MIDI sources. You have to be prepared to dispense with EQ on the tape returns, but this can be an acceptable compromise as there is always the opportunity to EQ the tape signal at least once, at the recording stage. All 24 inputs can, however, access at least one auxiliary, which is perhaps more important.
The four monitor source selector switches are mechanical latching types which can be selected simultaneously, so you can have Left/Right selected at the same time as Aux, as you would need to in order to hear effects returns at the same time as listening to the monitor mix. The Mute switches provided on the 12 input channels use a non-latching (momentary) action, which perhaps indicates that they may be destined for remote control at a later date. This opinion is confirmed by a blanked-off cut-out on the rear panel labelled 'Fostex MIDI Controller'. The Mute switches don't click when interrupting signal, which is all you can ask of them really, and is not the sort of thing you fully appreciate until you come across a desk where they do click! Mute status is indicated by a small LED within the switch and it defeats the whole signal path, including auxiliaries.
On the rear panel, input channels are furnished with both XLR, phono, and ¼" jack connectors. The XLR mic inputs are low impedance (2kOhm actual for 600 Ohm nominal microphones), balanced (Pin 3 'hot'), with a phantom switch sending DC on all circuits at 24V. Having gone to the trouble of offering phantom power at all, I can't see why it isn't the full 48V variety as there are a number of mics, in my collection at least, that won't run on anything less, and still having to mess about with an external supply unit when you are supposed to already have phantom power on the desk is very irritating. One part of the manual actually states that the phantom is "DC24V current", which is misleading for a user-guide that is trying to be of educational benefit to the inexperienced operator. 'DC24V' is a voltage which, when applied across a resistance, will cause a current to flow in the circuit, which should be expressed in Amps or, in this practical instance, milliamps (mA). You can't actually specify the current because it is dependent on the resistance (ie. the microphone) attached to the circuit, but you can specify the voltage, which is constant. You don't need to know that sort of thing to use the Fostex mixer, of course, but it doesn't help to encounter it expressed ambiguously when you are trying to learn.
Phantom power is also globally switched, with a warning never to connect dynamic mics when it is in operation. This would certainly be a bit of a problem if half your mics were condensers and half dynamics, but fortunately this too is not strictly correct. The warning should be to never connect an unbalanced microphone to a powered line, for a balanced dynamic will quite happily ignore phantom power. Get it right Fostex.
The Line and Tape inputs (both 20kOhm, -10dBV nominal) are quite separate and differentiated by using different connectors, with the Tape input employing phonos in common with most semi-pro tape machines, enabling simple phono-to-phono looms to be made up without the need for special cabling. An insert point is provided, using the conventional stereo ¼i" jack, although here the tip is the send and the ring the return, which is the reverse of many desks (including my own). Input channels are completed by a Direct Out jack, a useful facility often omitted. The output is post-fade, post-EQ and post-Mute, which is probably the optimum position.
Group outputs, or tape sends, are all on phonos with a second set of phonos offering a facility for injecting signals into any of the group or auxiliary buses, effectively allowing parallel connection of another mixer if desired. When mixers are used together, the difficulty is usually that their outputs and auxiliaries cannot access the same devices - a problem neatly avoided by this measure.
Aux sends and returns are all on jacks, with the returns configured so that a signal returned into just the left input can be panned anywhere across both channels, with true stereo or dual mono operation occurring when both jacks are used.
The monitor output completes the comprehensive array of connection facilities, employing separate ¼" jacks for the left and right monitor signals. System response is quoted as 20Hz to 20kHz (+1/-1dB line circuit, + 1/-3dB monitor circuit), with the signal-to-noise ratio specified at 65dB (weighted) for a single mic channel, or 53dB with 12 channels routed. The inter-circuit crosstalk figure quoted is 65dB (1kHz), which is perfectly acceptable.
The Fostex 812 mixer makes extensive use of plastic in the styling and construction of its casing, with just the module surfaces, the base plate, and connector panel being visibly metal. However, the resulting structure has a nice robust, rigid quality to it that makes you feel it should prove reliable. I am pleased to observe that, unlike some recent designs, the XLRs are mounted on the connector panel itself, rather than directly onto a connector PCB below and merely protruding through the panel. The extra physical support this gives is vital to connectors as heavy as XLRs, which can otherwise cause PCBs to flex, cracking the electrical track and inevitably leading to breakdown.
In use, the 812 recording mixer is a pleasure to work with. Too often, desks that try to offer the utmost versatility and to mix the best of in-line and split characteristics end up employing a confusing mess of non-standard procedures. This one has got it about right, however, combining the clarity of routing to visible group faders with the versatility provided by being able to turn the in-line monitor mix controls into extra auxiliaries. An excess of options can often confuse, but here they are mostly transparent at first, leaving the inexperienced user to 'grow into them' at his own pace.
The 812 is more than just the natural and perfect partner for the Fostex R8 8-track tape recorder, offering plenty of scope for handling synchronised MIDI gear beyond just the apparent 12 inputs. The addition of the MIDI control option, when it becomes available, will be a further attraction. Its many useful facilities, stylish looks, and compact dimensions will make the 812 a very attractive proposition beyond just the realms of a Fostex package and will, I am sure, gain it the serious consideration its performance and specification merit.
Fostex 812 mixer £999; 2016 line mixer £299 (both inc VAT).
Harman UK Ltd, (Contact Details).
Review by Dave Lockwood
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