Output levels of Sennheiser G3 receiver

[Tom Morrow]

My understanding is that the output connector on the Sennheiser G3 uses the two conductors of the "stereo" 1/8" connector for mic and line outputs level outputs, so that one can change from mic to line level just by swapping cables.

So which is the cable included with the ENG kit: Mic or Line level? I'm talking about the cable that has the locking 1/8" on one end for the receiver and the blue-banded male XLR on the other end.

Sennheiser seems to indicate that the cable produces a line output on their page:

Partfinder > CL 100

but my experience is that I get good levels when I plug it into my mic level mixer inputs, so I'm confused.

[Zoran Vincic]

That's the way the input on the bodypack transmitter works, not the output on the receiver.

[Tom Morrow]

Thanks, I think I was confusing the mic/line jack of the transmitter with the apparently mic-only output of the receiver.

I guess my question is really: Is it really true that there's no line level output from the EK 100 G3 receiver, so it must be plugged into a mic level input?

[Steve House]

Originally Posted by Tom Morrow

Thanks, I think I was confusing the mic/line jack of the transmitter with the apparently mic-only output of the receiver.

I guess my question is really: Is it really true that there's no line level output from the EK 100 G3 receiver, so it must be plugged into a mic level input?

Nope, the receiver AF output level can be adjusted in the menu over a 42dB range, from -30dB (hot mic level) up to +12dB (hot line). (manual, page 16)

[Rick Reineke]

In a pinch, the (portable) receiver can feed a -10dB input with the receiver's AF set to it's max output setting. It will not have a high enough output to feed a +4dB line level device.
I normally feed a mic level camera or mixer XLR input, with the receiver's AF setting to -18 or -12.

[Steve House]

Originally Posted by Rick Reineke

In a pinch, the (portable) receiver can feed a -10dB input with the receiver's AF set to it's max output setting. It will not have a high enough output to feed a +4dB line level device.
I normally feed a mic level camera or mixer XLR input, with the receiver's AF setting to -18 or -12.

The published specs for the G3 receiver says its nominal output is 0dBu when fed a 100% modulated RF signal, with a adjustment range on either side of that from a 30dB cut to a 12dB boost. Sounds like setting the transmitter AF level for full scale deviation on the meter and the receiver AF output level in its menu to +6 would drive pro line level inputs nicely. Am I misunderstanding their meaning?

[Gary Nattrass]

I have the G2's but they have the same level adjustments and find that I have to work at mic levels on the inputs to my mixer or camera.

I set the transmitter up for -20 and the receiver for -12 and that seems to give a good signal to noise ratio and I then feed my ENG mixer or panasonic HPX cameras via mic level inputs.

[Zoran Vincic]

I'm not sure if I would call +12db on my G3 receiver a hot line level as I have to use it with mic input trim set fairly high on my EX1 (although I set the output level of the G3 at 0db). If I switch the input to line level I have no trim and the signal is definitely way too low, even with +12dB output.

[Tom Morrow]

In my instruction manual I see only two statements that address receiver output, and neither says anything about dbu.

It describes the AF OUT menu item as: "Adjusts the audio output level. Adjustment range -30db to +12db, adjustable in steps of 6db."

And in the specs it says "AF output voltage (at peak deviation, 1kHz AF): 3.5mm socket: +11dbu (mono, unbalanced)"
"Adjustment range of audio output level ('AF Out') 42dB adjustable in steps of 6dB"



I did my own experiment. I set my g3 transmitter to sensitivity level 30 (the default, halfway between 0 and 60). At that setting an input 1k tone at 4dbu XLR balanced went full range, and 5dbu illuminated the AF PEAK light.

I set my g3 receiver to level 0 (the default, btw the +12 to -30 range). A DMM connected to the 1/8" output reads 345mV, which is -7dBu unbalanced mono.

So at default g3 settings, the system gain is 4dbu in, -7dbu out, or -11dbu total in this case.

In other words, it seems like a pro-audio line level signal fed into the transmitter would produce roughly a consumer level line signal off the receiver. In practice it behaves like a hot mic signal, because it's too cold to use as pro line level.

[John Willett]

Originally Posted by Tom Morrow

My understanding is that the output connector on the Sennheiser G3 uses the two conductors of the "stereo" 1/8" connector for mic and line outputs level outputs, so that one can change from mic to line level just by swapping cables.

So which is the cable included with the ENG kit: Mic or Line level? I'm talking about the cable that has the locking 1/8" on one end for the receiver and the blue-banded male XLR on the other end.

Sennheiser seems to indicate that the cable produces a line output on their page:

Partfinder > CL 100

but my experience is that I get good levels when I plug it into my mic level mixer inputs, so I'm confused.

The output level is adjusted in the receiver.

The output of the EK 100 is unbalanced on tip and sleeve only (the ring is not connected). It is supplied with two cables: one to mini-jack (tip and ring shorted at the far end so the sound is fed to both channels) and the other to an XLR.

[Steve House]

Originally Posted by Tom Morrow

...
I did my own experiment. I set my g3 transmitter to sensitivity level 30 (the default, halfway between 0 and 60). At that setting an input 1k tone at 4dbu XLR balanced went full range, and 5dbu illuminated the AF PEAK light.

I set my g3 receiver to level 0 (the default, btw the +12 to -30 range). A DMM connected to the 1/8" output reads 345mV, which is -7dBu unbalanced mono.

So at default g3 settings, the system gain is 4dbu in, -7dbu out, or -11dbu total in this case.

In other words, it seems like a pro-audio line level signal fed into the transmitter would produce roughly a consumer level line signal off the receiver. In practice it behaves like a hot mic signal, because it's too cold to use as pro line level.

So a full deviation signal into the transmitter produces a consumer line level output on the receiver if the output of the receiver is set at 0. Dial in +12 gain on the receiver output and it should be adequate to drive a pro line level input, perhaps a tad low but still usable, especially if there's some additional gain above unity available on that input..

I think people tend to forget that the transmitter gain and the receiver gain are independent. Any signal that drives the transmitter to full deviation will produce the same output level at the receiver for any given receiver gain setting. Whatever the signal source, adjust the transmitter AF gain to produce full deviation on the meter. You found that a setting of 30 with a +4dBu input did that. A mic plugged into the transmitter would need a different setting at the transmitter to give the same deviation. A consumer CD player yet another setting at the transmitter. A DJ's sound board output yet another setting at the transmitter. But if the transmitter was set in each case to give full deviation with only rare flickers of the 'over' light, you would get exactly the same output coming from the receiver, regardless of the actual level of the source being fed to the transmitter.

So the order of operations to get things set up with proper gain staging would be to first adjust the transmitter gain for full-scale indication on the the transmitter's meter without unduely lighting its 'over' indicator, then adjust the receiver output level to adequately drive whatever input you're sending it to, perhaps needing a combination of the receiver output setting and the input 'trim' setting of the destination device to get it just right. I would expect a 0 on the receiver to be about right for a prosumer camera line level input, values in the low negative range to be right for a mic level input, and +8 or +12 for line levels on pro mixers or cameras. In all cases, fine-tune it with the input trim control on the final destination device. But the transmitter gain has to be set up properly first before you can even think about receiver output level settings.

[Rick Reineke]

So Steve, are your saying, the EK100 receiver will drive a +4 input adequately? I can't see how. I'm not sure what spec Sennheiser is using for 0dB. Could it be the AF setting of +12dB on the receiver refers to the actual maximum peak output level in dBu or VU? In a +4dB 'real world' situation, program peaks regularly reach and exceed +20dBu.
In any case, I certainly can't get adequate input levels feeding +4dB input, even if sacrificing headroom on the transmitter to get a hotter output at the receiver.
My typical settings are (using a Tram) 'Sensitivity' setting on the transmitter @ -20dB (or occasionally -10dB for a 'low talker' or quiet scene) The receiver's 'AF' is normally set to -12dB, feeding a mic level input. Though I'd prefer to use line level, this works good.

[Gary Nattrass]

I agree Rick the outputs of my G2 receivers are just too low for use with pro +4db line inputs so I have to use them at mic level with -12db of gain on all my kit.

[Paul R Johnson]

My gen 1 receiver has enough ooomph to drive a pair of headphones - not mega loud, but loud enough to use for monitoring?

[Steve House]

As I understand it, the receiver output settings are refer to the amount of dB gain or cut on either side of zero. Tom found that when he sends a sinewave tone that just max's the transmitter meter, he gets a -7dBu output signal coming out of the receiver when it's out setting is 0. If you dialed in 12 dB of boost, that would give you an output of +5dBu, a tad above the +4dBu a sinewave reads at nominal studio line level. Given that peak levels for speech are about 6 dB or 8dB higher than sinewave tones, that's pretty close to the offical spec he quoted of +11dBu maximum output. If you dialed in 20dB of cut, that would give you an output of -27dBu, pretty close to a hot mic level.