What Beachtek adapter should I get?

[Zack Birlew]

Hi, I'm in the market to upgrade the audio on my GL1 (FINALLY!!!). I thought that I should go with the model designed for the GL1, the Beachtek DXA-4, but then I saw the DXA-8. Would I be better off getting the DXA-8 rather than the DXA-4? They both appear to be identical but the DXA-8 has more features. I'm planning on using a couple of Sennheiser Mke66 microphones. What do you guys think?

[Aaron Koolen]

They aren't the same. The DX8 has preamps, limiters and phantom power whereas the DX4 doesn't. If money's not a problem, go with the DX8. While you will probably be fine for most things with the ME66, you might sometime use another mic, or possibly need a bit of gain and then it would come in handy. I use the ME66 with my XM2 (PAL GL2) and it's worked fine for me without a preamp, but there have been a couple of times where I wished for a little more amplification, without wanting to pump up the in camera controls.

Of course, phantom is nice too cause it gives you a bit more selection when buying a mic.

If you go with the DX4 (passive) I'd almost look at signvideo instead. I have one of their items (along with a beacktek DX4) and while I think their customer server (As far as email answering goes anyway) is crap, I think their XLR BP is better than the DX4. The DX4 dials have preset clickable stops, whereas the Signvideo one doesnt (Which I prefer cause you can make minor adjustments over time better without it being as noticable) , but what I've found the best advantage is that there seems to be slightly more attenuation on the beachtek over the signvideo. Which generally means I have to turn the camera volume up more on that.



Aaron



Aaron

[David Ennis]

I like the DXA-8 over the DXA-4 also. But if you don't already own the ME66's I'd reconsider on those. They are very hot. On paper, the ME66 can be expected to cause clipping in the DXA-8 at sound pressure levels of 117 to 122 dB.

Also, clipping has been reported in this forum when plugging the ME66 directly into the mic input. According to Sennheiser, the output can vary from 37 to 67 milliamps per Pascal (1 Pascal = about 94dB), a pretty wide range. No surprise that some owners think they're fine and some others complain.

The ME66 frequency response curve is far from flat. Check out its published curve at sennheiser.com and compare it to that of the AT897 at audiotechnica.com. The experienced pros in this forum urge that we judge mics by listening to them rather than selecting based upon the specs, but the comments here in this case are pretty much consistent with the specs.

If what you really need above all else is a sensitive shotgun mic, then I guess the ME66 could be the best choice.

[Zack Birlew]

Well, I just want the best XLR shotgun microphone I can get without going into the $500+ range for a single microphone. What microphone(s) would you suggest over the Mke66?

[David Ennis]

The AT897, available at B&H for $280.

If you do a search on AT897 in the "Now Hear This" forum and you'll find that the pros think highly of it for the money. And what you save in purchase price compared the ME66 (especially if you're getting two) will pay for the upgrade to a DXA-8.

[Joe Mobic]

i was considering getting the Audio Technica AT4073a with the Beachtek DXA-6

would this beachtek dxa-6 work with the GL2 and the AT4073a?

[David Ennis]

Yes the DXA-6 will be fine. With the AT4073, a very hot mic, you should turn on the GL2's mic attenuation to avoid overloading the GL2's input.

[Joe Mobic]

what exactly would the difference be between turning it the GL-2 mic attentuation on or off....how would the sound differ?

[Joe Mobic]

I just experimented with the attenuation On and OFF
with the AT4073 and the beachtek dxa-6

with OFF - what I had for all my experimenting yesterday, i noticed that the AT 4073 was very sensitive and seemed loud


with ON - it was more mellow and smooth, however not as sensitive. from 3 feet away, the mic didn't pick up the sound like it did with attenuation on OFF.

hmmmm...... so is ON the way to go?

[David Ennis]

What MIC ATT ON does is reduce the input signal voltage received at the mic jack by about -20 dB. But with the DXA-6 trim control you can adjust the signal voltage coming out of the DXA-6 to anything from the full mic voltage coming into it down to zero volts. Therefore, with the DXA-6 you can have the GL2's MIC ATT on or off.

What you have to do either way is protect the GL2's input from a voltage high enough to cause clipping. You can't protect it by turning down the GL2's audio gain controls--that's too late. According to multimeter and oscilloscope measurments I made on my GL2, with MIC ATT OFF, the most the the GL2 input can take without clipping is about 14 milivolts. With MIC ATT ON, the most it can take is about 120 milivolts. When I did that study, I also compared the GL2's level meter readings to the voltage that was coming in. The reason I did all that is to be able to get to the bottom line for setting audio levels with the GL2.

Bottom Line:

1. With MIC ATT ON, set the GL2's gain controls to mid position.
2. With the sound you want to record happening, adjust the DXA-6 trim control so that the "normal" level of sound is at -12 dB (the big dot on the GL2 meters), and the loudest peaks go to -6 to -2 dB (the highest two dots on the scale).
3. If you can't get the level meters high enough even with the trim controls turned all the way up, then crank up the GL2's gain controls as necessary.
4. If that still won't do it, turn MIC ATT OFF and try again with the GL2 gain controls at mid position.

Notes:

1. If there is a big difference in loudness between normal loudness and peak loudness you either have to accept recording the normal loudness at a lower level, or accept distortion on the loudes peaks.
2. As I mentioned above, under most conditions with the DXA-6, the GL2 and the AT4073, you will probably be able to use MIC ATT ON or OFF. If you adjust as described above, there will be no difference in the end result

[Marco Leavitt]

Big difference between the audio on the GL1 and the GL2. As you know, your camera doesn't have a meter or controllable levels. You'll have limited success trying to prevent your camera from clipping by adding a limiter, but it will help. Still, I guarantee that you will get better results by going with double system sound, like HiMD, and buying a passive mixer to use with it. You can still use the mixer with your camera for those times you do decide to record direct to camera. I believe the knobs on the Beachtek mixers click into place, and aren't really designed to mix on the fly. You pick your level and leave it set.
We use a Studio 1 XLR Pro (now made by Sign Video) which lets you ride the levels because the pots don't click into place. Beachtek is nice for run and gun, because the knobs won't move on you, but I'd go with the Sign Video box for active mixing. If you're set on getting a preamp with a limiter, you might want to look at the SoundDevices MM1. It's single channel, but you don't need limiters on two channels, and you're mics are hot enough (if you go with the ME66s) that you'd don't need a preamp on both channels either. If you did get the MM1, you'll still need the passive mixer for the camera, because the MM1 only outputs line level. When you have a situation where someone yells, you turn the limiter on, and turn down the level on the passive mixer. This decreases the ratio of the peak, which is what you need for that camera. In all cases, you'll want to turn the attenuator on with the GL1.

[Joe Mobic]

thanks for the detailed explanation. the info presented by the above posts made it much more clear on how to manipulate the controls to tweak the sound I may need.

[Marco Leavitt]

Just to make one thing more clear, on the MM1 when you need the limiter to be more active, you turn up the gain, even though it seems counterintuitive. That's why you need the passive mixer to turn the level down further.