Extron XPA 1002 power amplifier

I came across this decommissioned Extron XPA 1002 amplifier at work and decided that it coukd be put to better use powering a pair of JBL monitors that I have. I originally had a QSC amp that was also decommissioned by by one of my clients but the thing literally “blew up” and tripped the MCB when it did so. Anyway, this little beast has these features:

• 2 x 60 watts @ 8 ohms
  2 x 100 watts @ 4 ohms
  1 x 200 watts @ 8 ohms (bridged)
• ENERGY STAR® qualified amplifier
• Professional grade signal-to-noise and THD+N performance
• Extron Patented CDRS™ – Class D Ripple Suppression
• Convection cooled, fanless operation
• Ultra low inrush current – no need for power sequencing

My speakers can handle 75 watts and I do not blast them so this little beast powers them perfectly. Ideally, you should always have amplifiers that are more powerful than your speakers. I know that QSC amplifier that blew up had a respectable 200 watts per channel. In any case, I need to make some special female XLRs to phoenix connectors so I can connect this amplifier to the flightcase that has my turntables and mixer so I can start mixing.

Trying to find MAC address of equipment

Quite a few of my clients whitelist MAC (Media Access Control) addresses so that the equipment can function on their network. More often than not, we have to collect the MAC addresses and pass them to the client for whitelisting first. Therein lies the problem. Sometimes, the equipment does not come with the MAC addresses listed on the equipment or on the box they are packed in. Take this QSC Core for example. This piece of equipment, costing a few thousand dollars, you would think that manufacturer would spend a little more to have the MAC address printed on a sticker or even printed on the chassis. The answer is no. So what I had to do was to connect the device to my notebook computer via the small D-Link switch that I bought some time back. After that I used Wireshark to scan for the MAC addresses. And thankfully, I was able to get them. But to be honest, this is not the way it should be. The MAC addresses need to be printed. Because of this, I wasted quite a few hours at the client’s place trying to find out MAC addresses. Come on QSC! Just print the MAC addresses on a sticker and paste them on the damn box!

QSC MX 2000a dual monaural power amplifier

In the early 90s, I was the DJ in a club in Orchard Road Singapore. the club’s DJ console setup was very simple. There was a mixer connected to crossover which in turn was connected to two of these QSC MX 2000a amplifiers. Now these amplifiers were real workhorses and it was the first time that I was introduced to QSC power amplifiers. These amplifiers could push out 450 watts into 8 ohms and 650 watts into 4 ohms. The quarter-inch balanced connections behind were a bit strange though. There is a RTS (ring tip sleeve) input and not TRS. The connections were ring (positive), tip (negative) and sleeve (ground). There were also some parallel-connected binding posts. I would have preferred to use those. I remember falling in love with those amplifiers and secretly wished I had them instead of my then Peavey CS-800!

QSC Touchmix-16 digital mixer

I had the chance to use this QSC Touchmix-16 mixer at an event fairly recently, say about a couple of weeks back. It was fairly easy to use and with all things new, it just takes some getting used to. One thing I like about it was that it was portable. My friend who brought it down had a special bag that came with it so he could travel with it and go to as many jam sites he could with it. The only thing I had against it was the gain knobs above each channel. They seemed a little flimsy and I was not convinced about their sensitivity after I plugged my DJ controller into it. I went to the website and found some of its key features:

• Capacitive touchscreen offers a wealth of on-screen information while also providing confident hands-on control
• 120 presets provide real-world live sound settings for commonly-used instruments and microphones
• Simple and Advanced modes offer either basic or comprehensive controls
• Anti-Feedback and Room Tuning Wizards simplify complex equalization tasks
• Real-time analyzer (RTA) provides instantaneous display of channel tonal balance and room response
• 10 Aux mixes provide superior monitor configuration capabilities
• 22-channel direct-to-hard drive record/playback — capture and recall performances without the need for an external computer
• MP3 playback direct from USB
• On-board multi-language user guide
• Download future upgrades directly from the Internet

One thing I really liked about it was the anti-feedback thingy it had. I could see the fader in the touchscreen “adapting” itself to the feedback when one of the mics got too “hot”. It was fairly easy to set up and my friend was controlling it via an iPad from some distance away.

So now, let us see. It is a good mixer. That I would agree on. It does the job. But the issue is the power supply. If the power supply can be improved upon, that would be great. There have been many issues with the connector at the rear of the unit. Would I get it? Maybe, maybe not. For $1800 (RRP) there are better ones in the market. But it is an interesting mixer and it fills a certain niche pretty well.

QSC GX7 power amplifier

I was using this for an event some time last year. I remember that the event was a success and the sound was loud and punchy. It was partly credited to this lovely QSC GX7 amplifier that were powering the two main speakers. Now in the past, I have never been an advocate, of sorts, to these QSC GX series amplifiers but I am a convert now. I have installed these amplifiers in a couple of places and I can safely say that these amplifiers can really push their power well and handle their jobs with ease. This GX7 for instance. Both channels driven, it can put out 725 watts of power into 8 ohms. Into 4 ohms, it can put out 1000 watts. Not too bad really. As for connectors, there are XLR, 1/4″ TRS for balanced connections, and phono for unbalanced connections. Features-wise? Here you go:

• Power levels matched to the most popular speakers used by entertainers
• Optimized for maximum real-world headroom into 4- and 8-ohm speaker systems
• Inputs: XLR, 1/4″ TRS and phono input connectors for compatibility with any source
• Outputs: Speakon® combo accepts 1/4″ (TS) plugs or Speakon 2- and 4-pole plugs (connects 2 poles only). Binding posts support all other speaker wiring systems
• Minimum depth chassis (10.1″ / 257 mm) fits in compact, inexpensive effects racks
• Lightweight – GX3 and GX5 less than 26 lb (12.5 kg). GX7 only 15.5 lb (7 kg)*
• Detented gain controls for precise setting and matching of sensitivity
• GuardRail™ automatically protects the amplifier and loudspeakers from damage due to temperature rise or overdrive without shutting down the show
• Front panel LEDs monitor power, signal, and clipping
• Subwoofer/satellite crossover built-in

I am still used to the Yamaha amplifiers that I have used for many installs and even Yamaha have come out with some good ones recently. But given the fact that these from QSC are really good, it has been making me think twice about which amp I should be getting.

Mixer and speaker install in a client’s place

Just the other day, about two weeks ago, I did an install in a client’s office. They had opened a new office, adjacent to theirs, and thus they needed some speakers installed. The speakers they installed were the 70V line versions so we had to get an amplifier that could handle all those speakers. We settled on this monster QSC amplifier and hooked up all the old speakers as well as the new ones. We also installed a Yamaha MG10XU mixer and a Shure SLX4 microphone. After it all was finished, the client was very happy with the result and I can safely say that this equipment will give the client years of dependable service.

QSC ISA500Ti Commercial Power Amplifier

Just yesterday, I installed one of these 70V line amplifiers in a customer’s place. It was a pretty straightforward install and I must say that the install went like a snap. I hooked this up to a few 70V line speakers and this amplifier powered them loud and clear. Only thing about this amplifier is that it is damn, bloody heavy. It should be with two huge toroidal transformers inside! I went to the QSC website to find out more about it and this is what I found out about it:

• Low-impedance outputs plus isolated 25, 70, and 100 volt outputs for distributed audio systems
• Rear panel gain controls for tamper resistance; 2-dB detents allow for quick and repeatable settings
• XLR and detachable Euro-style input connectors
• DataPort V2 for use with DPV2-compatible signal processing accessories (XC-3, SF-3, LF-3) and DSP-3/DSP-4 (with external power supply)
• Independent defeatable clip limiters for reduced distortion
• Selectable high-pass filters (50 Hz or 75 Hz) protect speakers and prevent speaker transformer saturation, with minimal effect on program material
• Front panel indicators include power, signal, and clip
• Covered barrier strip output connectors for safety agency compliance
• Automatic on-demand variable-speed fan: quiet normal operation, with maximum cooling when needed
• Rear-to-front air flow helps keep equipment racks cool
• Stereo, bridge, or parallel operating modes
• Comprehensive protection circuitry including DC, infrasonic, thermal overload, and short circuit protection
• 3-year warranty plus optional 3-year extended service contract

I connected this amplifier to the Euro connectors and I was mighty pleased with the outcome. The Euro connectors make installation a breeze with the screw-in terminals. Forget about soldering XLR connectors!

QSC CX108V 8-Channel 70V Power Amplifier

My client had two of these QSC CX108V 70V amplifiers conk out on them and they were duly sent for repair. Apparently there was a problem with the “housekeeping card” or whatever that is. So those offending electronic items were duly replaced and sent back after repair.

I have always been interested in QSC amplifiers. I can never forget when I had a pair of QSC MX2000 amplifiers 25 years ago in the club, doing a damn good job f powering some Turbosound loudspeakers. So I was equally in awe about these 8-channel units and this is what I found out about them after looking them up o the web:

 

• 100 watts per channel at 70 volts
• Compact size—only two rack spaces and 14″ deep for reduced rack space
• Channel pairs bridgeable for maximum flexibility
• Exclusive PowerLight switch-mode power supply technology for high performance and compact size
• Active inrush limiting eliminates AC inrush current, removing the need for expensive power sequencers
• Four HD15 DataPort connectors (one per channel pair) for Q-SYS networked control and monitoring
• Custom integrated gain control security cover for tamper-proof installations
• 1-dB recessed detented gain controls for fast and accurate settings
• Detachable Euro-style input and output connectors
• DIP switch control for clip limiters, high-pass filters, bridge mono and parallel operation
• Selectable high-pass filters protect speakers and prevent speaker transformer saturation with minimal effect on program material (50 Hz or 75 Hz)
• Comprehensive front panel indicators including signal, clip, bridge mono and parallel input LEDs
• Fully protected—including DC, infrasonic and ultrasonic, thermal overload and short circuit protection
• High-performance Class AB+B complementary bipolar output circuitry
• Lightweight—only 21 pounds (9.5 kg) for easier racking and shipping

And lightweight is true indeed. Unlike QSC amplifiers of old, these seemed almost featherweight. After installing them, they did the job and sounded as great as ever. Gotta love these QSC amplifiers. They will be giving many more years of service with no more issues…I hope!

 

QSC PowerLight 3 Series PL380 power amplifier

I am hearing a lot of positive things about this QSC amplifier. I am no stranger to QSC and their excellent amplifiers. I was spinning in a cub 20 years ago that had QSC MX-series amplifiers and those babies kicked serious butt. I used a QSC amplifier last year to do a sound check last year, powering a pair of huge subwoofers and the damn thing did not even blink when pushed. This is what QSC is famous for…great amplifiers that can take a beating and come back for more.  According to their website, about this PL380 power amplifier:

The PowerLight™ 3 Series is designed for the most demanding live audio users, whether in touring rigs or fixed installations. The most requested features of the PowerLight 2 series have been upgraded to deliver “the ultimate analog amplifier”, while the QSC Dataport ensures full compatibility with advanced digital processing and QSControl.net™. Three models range in power from 1250 watts to 4000 watts per channel at two ohms, all in two-rack space chassis that are only 15.6″ (40 cm) deep and 22 lbs (10 kg).

That explains a lot about what this amplifier can do. The PL380 is a Class D amplifier. I am no fan of Class D but I will make the exception for some, like the powered mixer driving my Yamaha Stagepas speakers. The specifications of this power amplifier series are as follows:

• PowerLight switchmode power supply for highest efficiency and improved audio performance
• Flow-thru air path and solid aluminum heat sinks for maximum cooling
• DataPort supports remote computer control and/or external DSP-4 modules
• Detented gain controls with 1 dB steps for precise calibration
• Removable knobs with lock-out security plate to prevent unauthorized tampering
• User defeatable clip limiters and selectable low-frequency filter per channel (3 Hz, 30 Hz, or 50 Hz)
• Three selectable input gains (26 dB, 32 dB, or 1.2 V)
• Front and rear panel LEDs indicate status of switch settings at a glance
• Parallel Dataport, XLR/M and XLR/F connectors for simple loop-through connectivity
• Neutrik Speakon® and “Touch Proof” binding post outputs
• Neutrik Powercon® power cable remains secure on the road
• 3 year warranty, plus optional 3 year extended service contract

The PL380 can deliver 1500 watts per channel into 8 ohms, 2500 watts per channel into 4 ohms and 4000 watts per channel into 2 ohms. Egads! Pretty good specifications but quality like this does not come cheap. But by and large, it is a great investment and I am pretty sure that you will be happpy with QSC, should you decide to invest in their power amplifier. I know I was convinced over 20 years ago.

Sound reinforcement does not have to be complicated

It is fairly easy to get started in the sound reinforcement business. You can start off by having a small system and offer services to event companies, tradeshows and the like. A small system does not have to be expensive. Take a look at the picture above. All it consists of are two Peavey dual 15″ speakers, a small Mackie mixer, a QSC power amplifier and what looks like an effects unit. Rack it up in a standard road rack and there you go. What would be ideal here in this picture, and would be required in some case would be a CD player and a graphic equalizer. But all this stuff is not super expensive and will perform well. I should know about this because I started off this way and I am still doing it, on a much smaller scale.