I was under the assumption that the Sennheiser ew 100 G3 system components were only compatible with each other (i.e., other G3 components), and that G2 components only got along well with other G2 components. But I recently became aware that a G3 receiver could be used with any G2 and G1 systems.

With that in mind, I was wondering what the drawbacks would be of using a G2 transmitter (either an SK100 bodypack, or an SKP100 plug-on) with a G3 receiver. I know the G3 receiver would be a diversity receiver, which is a plus, and that the G2 transmitter would have fewer frequencies available (4 per memory bank vs 10 per memory bank with the G3).

I already have a full G3 kit (bodypack and on-camera receiver). However, asking prices for G2 components are very low compared to equivalent G3 components, so the only reason to use a G2 transmitter would be to get a more economical (G2) plug on transmitter for my microphone, or a more economical (G2) body pack as a spare/backup.

If I combined those two components (G2 transmitter and G3 receiver), what would the drawbacks be? Would I lose quality, or reliability, or both? Any thoughts?

But I recently became aware that a G3 receiver could be used with any G2 and G1 systems.

Not exactly. Only those components that can both see the same frequencies. As long as you can share a frequency, you can mix and match. So they tell me anyway. When in doubt, ask Sennheiser.

Would I lose quality, or reliability, or both?

Both. The better question is, will it be enough worse to bother you? No one can answer that but you.

Sound quality and reliability can't be any better than the weakest link in the chain. Using a G2 component in a G3 chain will likely make the chain sound just like a G2 system. Which isn't at all bad.

As long as the G2/3 transmitter/receiver is on the same frequency block (and on the same frequency), they would work together OK. The G3 system has a slightly wider RF bandwidth and the G3 SK100 bodypack transmitter has more gain steps (60 dB, adjustable in 3-dB steps) as well as other user niceties. The G2/3 RF gain is the same (30mW) and the HDX noise reduction system is compatible. So for the most part, sound quality difference would not be audible with all other parameters being equal.. Upgrading to a professional lav mic element is recommended for either.

Rich is absolutely correct. The differences really don't impact on the use. In fact - as the damn things look so similar, I often mix and match accidentally. The bandwidth difference can be handy because you can squeeze 5 channels in our channel 70, while only 4 can be managed with G2.

I've still got a few original series bits of kit and they too work quite seamlessly. The only time I always use models from the same series is when using the multichannel systems where following Sennheiser's IM free plans is critical.

Just completed the Sennheiser wireless training at work and can highly recommend that you check out this book if you can:

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