Radian RPX-108P
Coaxial Loudspeaker

By Mark Farmer
As for any new product on the market there are so many that go unnoticed. Radian Audio Engineering, Inc. has been manufacturing speaker components (drivers and diaphragms) for many years. They also design and market some fantastic looking speaker enclosures.
One of the newest products in the Radian line is a small personal type of stage monitor. The monitor is made of 13-ply Baltic birch and coated with a new tough textured coating deemed Duradian™ from Radian. This finish is waterproof, scratch proof and reduces box resonance. Our company has begun utilizing a similar finish with great results. A pole cup on one end has been installed for setting on a tri-pod stand. Two different angles also have been designed depending on how close the monitor is placed to the performer.
I took the initiative to open the enclosure and see what made this little thing tick. Inside this well designed enclosure is a small circuit board with a passive crossover network attached. The heart of the Radian is a coaxial 8" speaker. This is a great design in that the horn diaphragm is mounted to the magnet of the 8" speaker. This dual diaphragm mounting normally used in the studio is called point source technology. The speaker mounting, crossover and construction of this box are all top notch. On the end of the Radian is a pair of Neutrik™ NL-4 connectors for easy hook up to most amplifiers.
According to Radian this little 17.5" x 12" will handle up to 800 watts of peak program and 400 watts nominal. Frequency response covers a broad spectrum from, 70Hz-20kHz with a maximum SPL of 119 dB. Light enough to carry under your arm, the RPX-108P weighs only 25 pounds.
IN USE
As usual, I was excited to demo the speaker. I hoped to have an event shortly after I received the product, but we did not have anything that fit the use. Therefore, my first test was at home in my own living room. I replaced my left home speaker with the Radian on the same speaker stand and set out to listen. A bit of extra juice came out of the Radian compared to the speaker on the right side of the room. The Radian monitor was around 6 Ohms and my other home speaker running a steady 8 ohms, hence for the slight volume difference. I sat down after adjusting the balance and tested out some of my favorite music on the Radian. my home amplifier, with 120 watts per channel, did not reach the limits of the Radian. In attempts to distort or overdrive the Radian, the 2-way home speaker was first to bottom out. The small monitor generated more sparkle than the home speakers and had quite a punch in the low end around 100Hz. High fidelity are two words that came to mind during this home demo.
At a recent corporate event, the Radian was utilized as a near-field monitor. Having to set up in the rear corner of a room did not allow me to hear any of the eight speakers set up in the rectangular room. In this setup, there were four main speakers and two pairs of delayed speakers reaching the middle and rear of the room. An auxiliary output of the console to feed the Yamaha processor and then ran it to the Crown 1200. No equalization was used to test the accuracy of reproduction. Speech and music playback were primary considerations for this event. I utilized the processing power of the Yamaha piece to time-align the Radian to the mains after time-aligning the other delay speakers in the room. Speech via the Audio-Technica podium microphones was reproduced accurately and detailed through the Radian point-source speaker. Lip smacking and breathing could be heard with grand intelligibility. Even with no EQ, the Radian sounded almost as good as the other 2-way speakers in the room. Music playback was just as pleasant and comforting to the ear. The 400 or so watts being produced from the amplifier did not get close to overdriving the ‘dual’ drivers within this enclosure. After the event ended, my co-workers and I wanted to see what the Radian could handle by sending it a healthy dose of volume and amplification from a few popular compact discs. Adding a bit of 80 Hz and a slight boost at 12 kHz via the parametric EQ within the processor produced great sounding (loud) results.
SUMMARY
I love innovative products from smaller companies. This is definitely one of those products. Live sound, musicians or corporate events could become a possible home for this product. compact size, product mobility and flexibility are a few of the strong points of this product.
Mark Farmer is a sound engineer with Live Technologies in Columbus, Ohio and a regular contributor to Pro Audio Review. He can be reached via e-mail at: mixthat@columbus.rr.com

Product Points

Plus
+High fidelity tone
+Compact size and weight
+Versatile
Minus
-None
Comments
A must have for the performer or talent at your event.

Radian Audio Engineering, Inc.
600 N. Batavia Street
Orange, CA 92868
Tel: 714.288.8900
Fax: 714.288.1133
Info@radianaudio.com
www.radianaudio.com