Tascam's new 464 Portastudio offers simultaneous 4-track recording plus a large number of inputs on mixdown, for sequenced MIDI sources to be run 'live' via tape-sync. Unusually for a cassette multitrack, the extra 'channels' involve no obscure procedures for reusing monitors or auxiliaries, and are therefore available all the time, throughout the recording process. Despite a host of sophisticated features, this logical configuration also makes the 464 particularly easy to use — an important consideration at the 4-track level of the market.

A dual-speed transport is used, giving compatibility with a conventional stereo cassette recorder at the lower speed, when necessary, without compromising audio performance when multitracking at the higher speed. As on all Tascam Portastudios since the original ground-breaking 144, dbx (Type II) noise-reduction is used. A Sync switch de-selects the dbx on track 4 and directs its signal in and out via dedicated Sync connections, so sync code does not have to pass through the mixer.

SUBSTANTIALLY BUILT

Personally, I rather like the look of the 464, in spite of it all too obviously having had a certain amount of input from a stylist at some stage in its development. I find the neutral pale grey finish and the muted pastel shades of the colour-coding more conducive to long periods of work without eye-strain than a matt black surface. The feel of the controls and switches helps contribute to an overall impression of a substantially built unit that will give many years of trouble-free operation. Fortunately, there is no external mains adapter to worry about, and the on-board power supply has a fixed mains lead. Access to the heads and tape-path for cleaning and de-magnetising is slightly hindered by the flip-up plastic cover for the cassette housing. I know I say this every time I look at one of these units, but why isn't part of the cover detachable to give better access, as on some stereo decks?

The 464 actually has a 'cleaning mode' — powering-up whilst holding the Play switch (without a cassette in the compartment), enables you to operate the transport controls, bringing the head block forward, and rotating the capstan. This is helpful, but unhindered access as well would be better still.

INPUTS

The Tascam 464 actually offers 12 controllable inputs, with four full-spec channels, two more stereo channels with a good range of facilities, and two further minimal stereo inputs, with just level and assignment controls. Twelve line level inputs are therefore provided, all via 1/4" jacks. The first four channels only also have XLRs for balanced mic inputs — the XLR and the jack share the same amplifier stage, and may not be used simultaneously.

The four main channels offer quite a comprehensive set of facilities by Portastudio standards, starting with a wide-ranging Trim control for setting gain (all other channels operate at fixed sensitivity, nominally -10dBV). The input source switching includes a neat little addition which further enhances the flexibility of the unit — channels can take as their source either mic/line or tape, or a third setting which sends the tape signal via the channel, but routes anything connected to the channel input directly to the stereo bus, creating a 'bus in' facility, either for yet more inputs or parallel mixer connection.

A decent little 3-band EQ is provided, with a sweep mid section and fixed-frequency, shelving HF and LF filters (Tascam have invariably incorporated fairly comprehensive channel EQs on their up-market Portastudios).

HF and LF offer +/-12dB at the usual frequencies of 10kHz and 100Hz respectively, whilst you can set the mid to operate with a centre frequency anywhere between 250Hz to 5kHz. Mid gain is +/-14dB. All EQ gain controls, and Pans, are centre-detented.

Two dedicated FX sends (post-fade auxiliaries) are provided on the first eight input channels. Obviously on the stereo channels with ganged controls you don't have independent control of send level from the two sources, but overall this is a generous allocation of auxs for a Portastudio, and I have no complaints about the configuration. Both aux busses have an aux master control for optimising the interface level with the FX units used. Channel facilities are completed by the rotary Pan control, which is used for bus assignment as well as stereo placement, and the 75mm carbon-track faders. The 464 has seven of these: one each for the four primary channels; two ganged stereo faders for channels 5/6, and 7/8, plus a stereo master fader.

STEREO CHANNELS

Stereo channels 5 to 9 lack only the sweep mid section of the EQ and the Trim (gain control) facility, in comparison with the first four. The 3-position assignment switch allows routing to either the stereo bus, or the mono Cue mix bus, with an off position. The inclusion of the routing to Cue mix option is very important here; if we assume that the primary use for these channels is for synced MIDI sources, it is obviously desirable to be able to monitor the channels at all stages during the recording. As the stereo bus is used for the record sends to tape, it can not form the basis of the monitor (cue) mix. However systems with 'additional remix inputs' often do not allow them to be routed to the Cue mix, which significantly reduces the effectiveness of MIDI 'virtual tracks'. This configuration has been well thought out and matches closely the real needs and working practices of this sector of the market.

The Cue mix is governed by just four rotary level controls, plus a Cue bus master. There are no Pans, as the cue mix is mono, and no FX sends (although you can still arrange FX in the foldback, at least whilst actually recording, by sending from the source channel, and returning, via one of the minimal channels, to the cue mix). The Monitor master control determines the overall level of both the headphone feed and the dedicated Monitor Out phonos, provided for connection to an external monitoring amplifier. Any of the six monitor sources may be activated simultaneously. The options are Left and Right sides of the stereo bus, either FX bus, the Cue bus, and external 2-track return — the integral switching for the latter is certainly a rare inclusion in a Portastudio.

The monitor mix is stereo when a stereo source is selected — if only one side of the stereo bus needs to be monitored, deselecting the other side places the remaining signal into both monitor channels.

RECORDING

There are two methods of recording on the 464: Direct, in which the channel's signal is sent to the correspondingly numbered track; or via the record busses. To use the Direct facility, it is merely necessary to press and hold the Direct switch whilst selecting the appropriate track-record switch. The Direct signal comes after the channel fader, and thus both Trim and the fader must be used to optimise record level. To record more than one channel to a track (or a channel to a different numbered track) requires the use of the busses, with tracks 1 and 3 assigned to the Left bus, whilst 2 and 4 are fed from the Right. Any channel can therefore address any track. The master fader is also in circuit when recording via the busses. You can use direct and bus-assigned recording simultaneously, to allow recording of separate sources on all four tracks.

TRANSPORT FUNCTIONS

The 464 is well-endowed with sophisticated transport functions. The basic facilities are all governed from suitably large switches with a good positive feel, but most of the interesting stuff is grouped into a bank of smaller switches adjacent to the large LCD display window. Working in conjunction with the electronic tape counter display (real-time, by the way), these allow you to store two memory points. You can locate to these points via a single key instruction — just hit Loc 1 or Loc 2 — and there's also an automatic return to zero function (RTZ), which works from either direction. Memo Check allows you to examine the memorised locations, should it be necessary.

With two memory points entered, pressing Repeat 1-2 enters an automatic playback loop mode (the machine plays between those two points before automatically rewinding and playing again, indefinitely); very useful for working out a part in the context of the rest of the track.

AUTO DROP-IN

Pre-programmed drop-in couldn't be simpler to use; with the track set to record, press Rehearsal and execute the drop-in and out as desired. The machine will rewind itself to the point from which it started shortly after you drop-out, and then wait for your next instruction. Pressing Play at this point will run through the drop-in, monitoring tape until the 'in' point and then switching over to input, just as if you had actually dropped-in. At the 'out' point, monitoring will revert to tape. Once again it will rewind itself. This lets you both practise the part, and be sure that the drop-in is viable (and that you have put the in and out points in the right place). When you are confident about everything, you can press Auto In/Out, and execute the drop-in for real.

Audio performance when punching-in, whether pre-programmed, manual, or via footswitch, is free of electronic vices, both on tape and in the monitoring.

Six rather low-resolution (eight-segment) bargraph meters are incorporated within the display window. These show track record levels, scaled from -20 to +8VU, plus the selected monitor source (ie. the stereo bus when mixing). Visual confirmation of which tracks are in Record, and whether they are sourced Direct or via a bus, is also provided. A large (but sensibly recessed, almost flush with the surface) rotary varispeed control completes the line-up of facilities — some form of visual confirmation of varispeed status, maybe even a percentage value, is perhaps the only omission from the display facilities.

PERFORMANCE

By Portastudio standards, the 464 is a very tidy little performer indeed, with subjectively low crosstalk, and sufficient HF extension (-3db @16kHz) to avoid the rather 'strained' quality on wide-band material shown by some units. It was often the case in the past that you could achieve significantly superior results on this type of 4-track combined mixer-recorder unit by bypassing the mixer stage and instead using a high-quality external mixer for mixdown (better still if you could also record via one, or at least use a superior stand-alone mic amp). Of course, you can still achieve better results this way, but the gap has been significantly narrowed in recent Tascam machines — Tascam are making some rather nice mixers these days, and some of the R & D seems to have filtered down through the range.

LOW NOISE

Headroom and mic amp noise would not disgrace a small stand-alone mixer, and source noise is by far the most significant contributor in this department, even with all 12 inputs routed. With dbx in use tape noise is, in the absence of signal, virtually undetectable. Of course, this performance is achieved at a price, and the broad-band compander principle used by the dbx system does rely on the presence of a masking signal in the same area of the spectrum as the tape noise. Low frequency signals on their own, will allow a burst of noise to be heard as the expander opens up on replay. This should not be viewed as significant; almost invariably, in real situations (as opposed to artificial tests designed to display the 'vices of dbx') there will be another signal present, or sufficient HF in the main signal, to significantly mask any noise modulation side-effects.

In my experience, almost all problems associated with dbx on Portastudios involve over-modulation in recording, driving the tape into non-linearity, making it impossible for the expander to reconstruct the original dynamics and leading to level-pumping and a dull signal (due to the HF pre/de-emphasis used in conjunction with the companding effect). If you have dbx on a narrow track format transport, why not make use of the fact that you are not fighting tape noise, and record at conservative levels? The Tascam 464 manual recommends that you average at 0VU, and peak at +6VU — personally I subjectively preferred the results gained by playing even safer than that, particularly on anything percussive that might under-meter to any degree.

Use it properly and the Tascam 464 is capable of excellent results on first generation material. Losses in the second-generation are to some extent mitigated by the more sophisticated EQ available. A fair amount of EQing is inevitable when track bouncing, and units with only a fixed EQ tend to finish up with a marked frequency signature to the overall spectrum — all signals have been boosted at the same HF frequency, or cut at the same LF point. The 464 passed the famous '10-track bounce' test as well as any unit of this type I have yet encountered.

The level of wow, and particularly flutter, was subjectively very good on the brand new machine I was testing — the poor flutter performance of many 4-track cassette transports as they get older is often attributable to poor routine maintenance. With proper attention to capstan and particularly pinch-wheel cleaning, there seems no reason why the 464 should not maintain its high standard of performance in this area.

CONCLUSION

Tascam's 464 looks ideally matched to the requirements of the typical combined tape/MIDI system user. Whilst there is very little in the way of reasonable expectations that it does not fulfil, it does so in the most obvious and intuitive way possible. There are no non-standard procedures required, and apart from the restricted bussing arrangements, the working situation equates closely to using a separate desk and recorder (which is certainly as I think it should be - Portastudio owners will probably become component system owners one day). Build quality and reliability, we take for granted from Tascam these days, and audio performance is surely pushing at the limits allowed by the format.

The 464 enters the market ideally specified to fill the gap between the high-end 'MIDIStudio' concept, with its sophisticated synchronisation options, and the typical, basic 4-track configuration. In any field, it is the radical new designs that get all the attention, but it is steady revision and refinement that sometimes leads to the definitive model. With its multiple inputs, superior audio performance and ergonomic functionality, the 464 is very much a 'second-generation' Portastudio, and looks certain to do as well for Tascam as their other products in this area.

Further information

Tascam 464 Portastudio £680.33 inc VAT.

TEAC UK, (Contact Details).