Equipment Review: Beach Tek DXA-8
by: Bryan Beasleigh

I've spoken with Harry Kaufmann, The Chief Product Specialist of Beach Tek on a number of occasions and always expressed an interest in anything new. I was flattered when Harry offered me the loan of his new product, TheBeach Tek Ultimate Adapter.

The DXA-8 is a 2 channel, battery powered microphone adapter with built in preamplifiers, limiters and dual phantom power.

The Beach Tek DXA-8's features include:

• Two transformer balanced XLR inputs
• One unbalanced 1/8 mini jack mono input to right channel
• Transformer isolated unbalanced 1/8" stereo mini jack
• Two low noise preamps with independant gain controls from -10 to +15 db
• Two independantly switchable limiters make the output "virtually unclippable"
• Limiter have separate LED indicators
• Dual switchable 48volt phantom
• Easily accessed 9 volt battery compartment.
• Front panel battery LED indicator.
• Switchable mono / stereo mode
• Switchable grounding, supplies either isolated or connected ground between the adapter chassis and output cable ground.

The following is the opinion of a sincere amateur. I'm no stranger to electronics, but I'm also no pro.

I was impressed by the ergonomics of the unit. The build quality is impressive. The gain also appears to be quite adequate for mics with an output as low as 2.5 mv.

For the person that wants to be able to use a mic on phantom power and preamplify to get a better quality of sound, the unit is great. The limiters will most certainly stop what could turn out to be a catastrophe should an unexpected volume change occur.

I did several rounds of tests. They were all basically the same 5 repeated with different mics and at different levels. I captured all footage to my PC using Vegas 4 and stripped the audio track out leaving it as 48hz PCM. Output from my PC is through an M Audio 2496 through a very neutral Quad Electrocoustical preamp and amp. I then played back all tracks through one Yorkville nearfield monitor.

The Test

The DXA-8 was connected to my VX2000, with various mics in in pairs. The Scheops MK41, Sennheiser ME66, Oktava MC012 and AKG D230 (dynamic). These mics have an output of 13mv, 50mv , 10mv and 2.5mv, respectively.

With the VX2000 gain set at 20-25% no condenser mic required a gain of more than 60% The AKG D230 required a 40% gain in camera and 75% from the Beach. The quality of recording was fine with no noticeable hiss.

The Beach works with mics at all levels from 2.5 mv on up.

1. The Beach was tested as above and with Limiters off.
2. The same as above with limiters on.
3. An equivalent test using my Sound Devices 302 mixer, with line out (+4db) run through the VX2000 using line attenuation.
4. As above using -35db output into mic in, with no attenuation.
5. Using the 302 @ +4db into the cameras VTR audio terminals.

Preliminary listening showed that the higher priced Sound Devices 302 sounded similar to the Beach DXA-8 when input at mic level.

The DXA-8's limiters result in a somewhat harsher sound but only when the threshold is exceeded. This is better with than without. Without, you lose whatever has exceeded 0db.

The 302 input at line level was marginally better and the adjustable limiters were also smoother but then the 302 is 3 times the price and twice the size and weight.

Several things did come out in the initial teasting and while not directly related to the DXA8 operation will impact any decision to buy one.

For my tastes, no preamp setup, feeding through the VX2000's mic pre circuit will ever be satisfactory. The audio input through the cameras VTR terminals was as good as you could want for 16bit audio. It was as good as my Marantz PMD670 flash recorder.

As a result I'm sending my camera to have the audio path modified so that all audio in will be routed through the RCA audio output terminals.

For most the Beach DXA8 will be more than sufficient. The sound differences only become apparent with the more expensive mics. The major problem is more a result of a poor in camera preamp than a deficiency in the DXA-8

For more information visit: www.beachtek.com