Comprising a conventional mixer section, a stereo power amp, a digital effects section, and a pair of seven-band graphic equalisers, the Powerhouse Horizon from Studiomaster is a higher powered version of the reliable Vision. Paul White looks towards the Horizon.

Studiomaster's 350 + 350W Powerhouse Vision was one of what I would call the first wave of 'serious' powered mixers, and it is testament to the inherent 'rightness' of the design that the higher powered Powerhouse Horizon is little different. The package comprises a fairly conventional mixer section, a stereo power amp, a digital effects section, a pair of seven-band graphic equalisers, and a plug-in slot for an optional active crossover. The two power amplifiers can be switched so that in smaller venues, one amp can drive the FOH speakers in mono and the other can drive a monitoring system. In this instance, one of the graphics may be dedicated to FOH and the other to the monitors. The desk also has both Left/Right and a stereo Group (feeding back into the stereo mix); the graphic EQs may be switched out of the power amp feed and into the Group path if required.

Other refinements include a simple memory system that remembers not only effect settings, but also the Aux mute status and the footswitch setup. Memories may be called up from the front panel or via MIDI, although the four most commonly used settings may be allocated to four buttons for instant access. A certain amount of on-line help (in a choice of four languages!) is provided via the alphanumeric plasma display above the effects section (it also issues fault warnings). There is even a pin number feature that allows you to lock out uninvited guests.

PROTECTION RACKET

An intelligent amplifier management control system, or AMCS, keeps the amplifiers ticking over at a sensible temperature while checking for potential problems. A very sensible addition is the inclusion of limiters, which prevent the amplifiers being run into hard clipping. In fact, the whole amplifier protection system is surprisingly elaborate, starting with a relay-less muting system that prevents DC thumps when switching on or off. If a fault occurs that threatens to place a DC voltage across the outputs — one of the most certain ways to kill drivers — a thyristor 'crowbar' circuit comes into action and effectively shorts out the output, thus protecting any connected speakers from damage. The cooling fan's speed varies according to heat sink temperature, but a power monitoring circuit also switches the fan on when a temperature rise is anticipated.

Because of the higher power rating of these amplifiers, the speaker connectors are Speakons (the Vision has both Speakons and jacks). With amplifiers of this power, it is possible to get potentially dangerous electric shocks from the amplifier outputs, so use of Speakons at both ends of the cable is recommended.

LAYOUT

The review model has eight mic/line channels, the last two of which can be used either as mono mic channels or stereo line channels. The complete package can be carried reasonably comfortably by one person. The side cheeks have wide lips, making it easy to get a firm grip, and the console isn't so wide that lifting is awkward, as is the case with some powered mixers. If you get a padded carry bag made for it by a company like Capital Mamba, you can carry it out of the gig in one hand.

All the mono channels are equipped with mic (balanced XLR), line, and TRS jack insert sockets; phantom power is available globally via a recessed switch in the master section. No insert points are fitted to the stereo channels — instead there's a mic input XLR and two jacks labelled Left/Mono and Right.

All the mono channels are identically equipped with an input gain trim, three-band EQ with sweep mid, sends for the internal reverb, plus one post-fade auxiliary, a pre-fade auxiliary, one dedicated foldback send, and a pan pot. A Listen button solos the channel signal on the headphone out (and meters), and the channel peak LED remains on to double as a Listen status indicator. A single button selects the L/R or Group, and a 70mm fader controls the channel level. The stereo channels include a second pot for Line gain, but lack the sweep mid EQ option.

Slightly unusual is the fact that the HF and LF EQ sections (12kHz and 60Hz respectively) have a bell response rather than a shelving response. This makes a lot of sense in a PA environment, especially at the LF end, because it means you can apply boost to a bass drum or bass guitar, without adding an equal amount of boost to all the frequencies that come below it. This should result in less low frequency booming and place less stress on the amplifiers and speakers.

All three EQ bands have a ±15dB gain range, with a mid frequency variable from 350Hz to 6kHz on the mono channels. Screened scribble patches are at the bottom of each channel strip, but I imagine these will get covered with tape in the time honoured way.

"The quality of sound is fine, the EQ is rather better than on most small mixers, and the effects are really very good..."

MASTER SECTION

The Master section is where things start to get interesting. There are reassuringly few controls, and they are divided into logical groups. For a change, I've decided to start at the bottom and work up, extending the sense of anticipation by leaving the effects section until last.

Separate faders are provided not only for the Group level and the Left and Right outputs, but also for the Foldback (send) and Reverb (return), the latter controlling the level of the on-board effects unit fed back into the main stereo mix. Directly above are the two channels of graphic EQ where an Assign button allows these to be moved from the power amp path to the Group, enabling selected channels to be EQ'd.

A conventional rotary control sets the overall power amp level, and above this is the Split button, which allows the desk to drive both FOH and monitors (in mono), rather than being used conventionally in stereo. The headphone outlet, which has its own level control, may be switched to listen in on the stereo output or the Foldback output. When a signal is solo'd using one of the Listen buttons, the Listen signal takes priority in the headphones and on the meters.

A small hatch below the headphone section provides access to the active crossover slot, and Studiomaster can provide plug-in cards operating at different frequencies. The principle is that once a card is fitted, the internal power amps carry only the mid and high of the spectrum, whereas an external amplifier, fed from the line outputs, is used to amplify the bass end of the spectrum.

These days, it's not uncommon for bands to record their gigs to find out what went right and what went wrong. The Powerhouse Horizon makes this easy by providing phono tape ins and outs along with a Playback button, which allows recordings to be played back through the console. There is also a pair of jacks, which function as a stereo return (the Left input may be used for mono only use). No level control is provided, but as effects units invariably have their own output level controls, this isn't a problem.

EFFECTS

The effects section shares the top of the panel with the main meters, and these are calibrated in both dBs and power output (Watts). A red peak LED shows the maximum signal level, above which limiting takes place. In stereo mode, the meters work as expected, but in Split mode, the FOH mix comes up on the left meter and the foldback level on the right meter. Listen takes priority to show the solo'd signal level on the meters.

In all, there are 82 different effects options to choose from, all based upon delay, reverb, or their combinations, and the reverb menu includes gated and reverse options. Although these are in effect presets, their character may be varied by selecting one of three preset EQ curves using the Reverb EQ button. This steps through the four possible permutations: the Warm and Bright LEDs on or off. Further overall effect EQ control is provided by the EQ Tilt fader below.

Any delay effects may be modified using the Regen control to vary the amount of feedback, and hence the number of echo repeats that occur. Regen may be switched on or off, but applies only to the delay effects, not to reverb. A master Reverb button turns the effect on or off, and a peak LED shows if the internal effects processor is being overloaded. It is also possible to bypass the effect using an external footswitch, depending on the footswitch setup.

Right at the top of the panel is the memory section, comprising a handful of buttons, a single data entry knob, and a long plasma window. A memory stores not only the effects patch being used and the EQ settings, but also effect on/off status, regeneration on/off status, standby status, and the Aux 1 and 2 mute settings. Separate buttons, each with their own status LEDs, are provided for the Aux Mutes and Standby, so you don't have to program these parameters if you don't want to.

The easiest way to set up effects is to use the data entry knob to pick a suitable preset, modify it using the EQ and regen controls, then store it in one of the four Memory buttons. This is exactly what I do — four different vocal treatments are often quite sufficient for a typical gig — and changing effects is just a matter of jabbing the right button. However, for the more ambitious 'power user', the console allows 15 more programs to be set up, named, allocated MIDI program change numbers, and stored. Patches may be given names of up to nine letters.

MIDI users can call up any patch on the selected MIDI channel, using Program Changes. A simple but immensely practical inclusion is the ability to turn the effects on and off using MIDI Start and Stop messages. This is great for drum machine or sequencer users, because at the end of a song, the effect will automatically switch off so that you can announce the next song, then, as soon as the next song starts, the effect comes on automatically. More manual rock and rollers such as myself need to program the footswitch to do the job — the footswitch may be set up to handle: reverb on/off; regen on/off; standby, memory cycle, and program step. In Memory Cycle mode, the footswitch runs through the four user memories, while in Program Step, it runs through the 15 'Power User' memories.

"The Powerhouse Horizon is one of the most powerful all-in-one powered mixers you can buy, yet it is attractively priced, very portable, and includes all the essential facilities needed for conventional gigging jobs."

HELP AND SECURITY

I'm all in favour of any security measures that can be taken to prevent equipment theft, but the pin number system here can be a double-edged sword. In effect, you have the option to set up a four digit pin number (based on Memory buttons 1 to 4), which must be entered every time you switch on the console, before it can be used or any effects settings changed. What happens if you forget it? On the other hand, if the number is left set to 1111, the facility is overridden. Then what happens if your spiteful little brother finds the manual and programs in a number of his own and demands a supplement to his pocket money to unlock your mixer?

If you choose to use the pin number facility, a wrong pin number entered more than three times in succession locks you out. In practical terms, this means the console times out for the next two hours, by which time the caretaker is cleaning up, your audience has gone home, and you're wondering how you managed to jam your way through a whole set of instrumentals!

Finally comes the on-line help, which is called up by means of the dedicated Help button. This is context sensitive, so whatever you were last struggling with determines the messages you get. This only applies to the memory section of the console of course, but it does talk you through setting up the footswitch (including selecting momentary or normally open/closed types). When setting up the console, you can change the language from the default English to French, German or Spanish.

IN USE

Having used the Vision version of the mixer on a number of gigs, I can confirm that there is very little to criticise about its design or performance. Although there are minor changes to the Horizon, as well as greater power, the overall layout is much the same. It's also surprising that the Horizon isn't much heavier than the Vision despite the power increase.

The quality of sound is fine, the EQ is rather better than on most small mixers, and the effects are really very good, especially some of the combined reverb and delay programs, that are spot on for rock and pop vocals. I feel the programmability options may offer more than is required by most users, but the four direct access programs are both easy to set up and use. In fact, the only thing I really think needs improving is the footswitch input, which seems very susceptible to contact bounce. Very often you try to turn on the reverb, but the contact bounce within the footswitch (not supplied) turns it off again, and similarly, you think you've turned the effect off to announce the next number, and there you are in a virtual Paddington station! A simple flip-flop with a built-in delay of a few tens of milliseconds should eliminate this problem. Also, rather than relying on the user to buy a general purpose footswitch, it would have been useful to have a factory option with an in-built status LED, just for confirmation, or better still an optional foot controller containing a bypass switch and four Memory switches. I know you can do this all via MIDI, but in reality, most bands rarely use MIDI outside the keyboard rig.

Having the effects EQ contour on the Powerhouse Horizon adds a little more flexibility to the effects programming, and the built-in limiters are more than welcome. Why doesn't everybody include them? Personally, I don't think the PIN number feature is much of a deterrent against theft — who knows it's there until they've nicked the desk anyway? Although you can choose not to use it, this leaves the system vulnerable to mischievous intentions. These minor criticisms aside, the Horizon is a great performer.

SUMMARY

The Powerhouse Horizon is one of the most powerful all-in-one powered mixers you can buy, yet it is attractively priced, very portable, and includes all the essential facilities needed for conventional gigging jobs. If my experience with my Vision version is anything to go by, the Horizon should also be reliable.

The mixer can be split to handle both FOH and monitor mixing for smaller gigs. It can also be expanded by means of an inexpensive plug-in card to drive active two-way systems. The on-board effects are also sensibly chosen for vocal use, although there are some less obvious effects, such as reverse reverb, for those weirder moments.

Having graphic equalisers built-in is useful for general tweaking, but don't expect them to do a great job in tackling feedback — you need a 30-band, third-octave equaliser to do that properly. However, the majority of what you get is really well thought out. If you need power and flexibility, but without excessive weight or cost penalties, the Powerhouse Horizon is definitely a mixer not to miss off your short list.

Powerhouse Horizon £1761 inc VAT.

Studiomaster Diamond Limited, (Contact Details)

MEMORY SECTION