Paul White looks over the smallest mixer in Soundtracs' new Topaz range.
Just as Soundcraft set up Spirit to fight their corner in the home recording and semi‑pro live sound markets, Soundtracs appear to be doing much the same thing with their Topaz range of mixers. The Topaz Mini, reviewed here, is the smallest mixer in the range, and is obviously aiming for a share of the action currently enjoyed by Mackie's 1202 and the smaller Spirit mixers, as well as the countless Mackie wannabees already out there jostling for their share of the action.
Controls
Housed in a fairly plain but undeniably robust chassis, the free‑standing Topaz Mini (rackmount option available) operates from an external power supply. Four mono mic/line channels are provided, plus a further four stereo line only channels. All the mono channels have fixed‑frequency, 3‑band EQ (working at 10kHz, 1kHz, and 70Hz), plus insert points, while the stereo channels are equipped with basic 2‑band EQ (operating at 10kHz, and 70Hz). The stereo channels have no insert points, and there are no master stereo inserts (although on a mixer of this type, it's rarely a problem). All EQ bands offer the expected 15dB of cut or boost, and because there's no EQ bypass switch, the controls are all centre‑detented for easy zeroing.
Like most of its competitors, the Topaz Mini has two aux sends per channel. Aux 1 can be switched globally from pre‑fade to post‑fade operation, enabling it to be used either for setting up a monitor mix, or as an effects send, and Aux 2 is a dedicated post‑fade send, which would normally be used as an effects feed. There are no aux send master level controls, so you have to rely on the input gain controls of your effects devices — again, a strategy adopted by manufacturers of similar mixers.
While the mono channels have a fully adjustable input gain control, the stereo channels are simply fitted with switches, so that they can be optimised to ‑10dBV or +4dBu operation. Phantom power may be switched onto all the mic inputs via a switch in the master section, and every channel has a Pan and Level control as well as a Solo button.
As with many small mixers, all the mix levels are set using rotary controls rather than faders, the master output level being adjusted by a single stereo pot. Having two stereo returns means that you don't have to tie up any of the input channels in order to add effects, and for basic recording applications, there's a 2‑track In and Out on phonos. When the Tape button is depressed, the 2‑track is fed into the main mix via the Aux 2 level control, but rather than the tape return replacing the existing mix, it adds to it. Although this provides an easy way to add a taped recording, or other stereo source, to the main mix, you have to be careful to ensure the Tape button is up while recording, or you'll run into feedback problems.
Since this mixer doesn't have a separate main stereo output, or control room/monitor output, any monitoring of solo'd signals has to be done using the headphone output. In addition to the eight input channels, the two aux sends may also be solo'd, and the system works on the PFL principle, which means that the solo level is independent of the channel level control setting. As is common practice, the solo'd signal also comes up on the main meters, which provides a simple and accurate way of optimising the input gain settings. A large, bright red LED lets you know when one or more Solo buttons are down, and there are also Power On, and Phantom Power On LEDs.
The main outputs, and the mono line inputs are electronically balanced, with the wiring information conveniently screened on the rear of the mixer case. Although the aux sends aren't actually balanced, they are pseudo‑balanced using a compensated grounding system — so, when used with balanced connectors, there is a benefit in reducing the risk of ground loop hum. The PSU connects to the mixer via a locking DIN‑type connector, and a rocker power switch is located on the rear panel.
Performance
Technically, the mixer performs very well, its limited number of channels and short signal path contributing towards its low noise, distortion, and crosstalk figures. The controls have a reasonable feel to them, and don't wobble, courtesy of a moulded nylon bush that provides a bearing surface between the potentiometer shaft, and the hole in the front panel metalwork. Everything works quite intuitively, although you have to be aware that there is no mic/line switching, so both mic and line inputs are active. The only minor quibble on a practical level is that the embossed metal feet on the bottom panel don't offer the same degree of grip, or protection from scratching, that rubber feet would.
About the only subjective area of this little mixer's performance is the EQ section, and as I rather expected from the specifications, the high and low shelving controls work pretty much as you would want them to — they are more than adequate for general warming and brightening, and they have at least twice as much range as you're ever likely to need. The mid‑range control, on the other hand, is preset at 1kHz, which is quite an unpleasant‑sounding part of the audio band. In practice, this makes mid cut exceptionally useful for cutting out boxiness or mid‑range harshness, but by the same token, there are very few situations where it makes a useful contribution used in boost mode. According to Soundtracs, they did a blind test with several of their engineers to decide what mid‑range frequency was most useful, and they nearly all ended up choosing frequencies of around 1kHz, so if you have to have a fixed, rather than swept control, perhaps this isn't such a bad compromise.
The noise performance is as good on a subjective level as it is on paper, and the sound has a clean and transparent quality to it. Having said that, the frequency response, which is 1dB down at 30kHz, might have usefully been extended to 40 or 50kHz. On balance though, this is a well designed, well engineered little mixer, with a variety of uses — which is just as well, considering the crowded marketplace it's entering.
Brief Spec
- EIN ‑128dBu
- Distortion Better than 0.007% at 1kHz (line)
- Channel Crosstalk Better than 85dB
- Frequency Response 20Hz to 30kHz +/‑ 1dB
- Output Levels +26dB (balanced masters), Aux outputs +21dBu (ground compensated)
- Dimensions 329 x 322 (482 with rackmount option) x 85mm
- Weight 4.15Kg
Pros
- Clean, quiet audio path.
- Solid construction.
- Versatile.
Cons
- External PSU isn't always convenient.
Summary
A very simple, yet technically proficient mixer with many applications in live recording, hard disk recording, and general studio applications.