Line Level Input Question - XHA1 and Rolls MX422
 

Hey all,

I am running from my field mixer with a line level output and in to the XH A1 with the line level input. The problem is that I have to put the input levels on the camera to the absolute max, and even so I can't get the level up to 0dB with the input tone.

I feel like I am going to have to run mic level out of the mixer to mic level in on the camera, but that is just wrong to me.

Has anyone else had this problem? Is there anything I'm missing?

The mixer is a Rolls MX422.

Thanks in advance

Are you saying that you set the 1k tone on the 422 to 0 on the VU meter,
and you have to turn the input on the A1 all the way up to give a -20 reading on the A1?

Do you have the pad engaged on the 422?

Yes, that is exactly what I'm saying.

I do believe that the pad was off. The device was in the hands of my sound expert, I will double check with him.

The specs on the Rolls 422 are not very clear on its output capability, but it apears from some info on their web site that when set to line level output, 0 dB on the meter corresponds to 0 dBV (1 volt) output. The output impedance is not stated and it can be an important consideration. From the circuit diagram in the manual, the mic level the output impedance looks to be about 470 ohms, a somewhat unusual number.

Subject to several dB variance depending on the mixer output impedance, 0 dB on the rolls meter should corrspond to around -20 dB (give or take) on the A1 VU meter with the manual gain. Keep in mind that 0 dB on the A1 is max allowable signal level, and trying to go above that level results in clipping. 20 dB is typical headroom for a professional recording system. Industrial / commercial analog mixers typically set 0 dB as the "average" record level (which works Ok for analog meters with swinging pointers), and usually have indications well above "0" for peaks/transients, clipping at around +20 to +25 dB. Digital systems typically take 0 dB as the max allowable signal level, and set average levels below that. 12 dB below is common for consumer and prosumer gear (the green dot on the A1 EVf scale), and 20 dB below is more common for pro gear.

If you really want a higher record level on the A1, try the MIC settng on the mixer, and MIC ATT setting on the A1.

The MX422 has two trims for the meter readings if you open it up. The MX422 is setup stock at pro level line level.

You can adjust the meter reading with two trim pots you turn with a small screwdriver once you take off the mixer case. They talk about this on their website briefly.