John are the sonics noticeably different between the G2 and the G3 series units?

The G3 have a better bottom end (they go lower in frequency), better selectivity (you can get 6 IM-free frequencies in the 863MHz band instead of 4) and the pocket receiver is now diversity.

Sonically they are very similar, but you will notice the better low-end response.

I hope this helps.

frequency range
 

I notice where the g3 is offered in several frequency ranges...516 to 558 MHz, 556 to608 mhz and 626 to 668 mhz.
If I plan on using this all over the country or even outside, has anyone determined what range might be considered the "safest" or "most usable" in most unpredictatble situations?

Talk to Sennheiser USA.

In the USA you can, I think, use bands A, B and G.

Definitely *not* band C - and I think also not D and E.

The Lectro Digital Hybrid series eliminates the compander circuitry employeed by low end RF units, which results in a fairly flat frequency response curve (when the mic element is removed as a variable). It's a fundamentally different way of transmitting the audio stream via wireless.

Just out of curiosity, what's the response curve look like when compander circuitry is used? Does a good mic compensate for a dip in frequency response...or does a good mic simply end up not compounding an already grim problem?

A compander does the opposite in the receiver to what it did in the transmitter.

So - if it boosts by 1:2 in transmission, it compresses by 2:1 in reception. SO the output should be the same as the input - just without the FM transmission noise.

That's the theory.

Err uh,

Usually a compander is used to compress audio levels first, then expand them to normal upon reception. Think of the old DBX noise reduction system.

In an FM system, compressed modulation has the effect of allowing more channels for a given frequency block, since compressed amplitude equals smaller FM bandwidth.

According to the Sennheiser manual, the compander lifts the level of quieter audio before transmission, then lowers it again after reception. This increases the signal to noise ratio for lower level signals which is when the noise would be most apparent. It seems similar to Dolby noise reduction for cassette tapes.

I guess there are 50 ways to build a noise reduction system. Dolby was one of them, but it was pain since it used a calibrated level to switch preemphasis..and tape formulations were all over the map. From thaty simple description it would appear sennheiser is a doing some sort of level switched gain... but we'd need a finer description to know for sure how their circuitry really works. I really did love DBX back in the day...

Bu this is all academic OT anyway... :)

" I really did love DBX back in the day..."

I did too but when I listened back with more experience I realised why everyone else seemed to dislike it. It pumped on the bass guitar and other things something cronic.

Companders are not all equal. The Sennheiser 5000 series has an incredible sound compared to a Trantec for instance. Huge price difference though.

The key lies in the FM noise as John says above. I rarely hear it on my Audio 2040's but you can if recording room tone and someone is banging next door. That sets off the breathy noise of the compander circuit somehow. Must be that FM noise again.

I posted this in another thread but here's an example of what I'm doing with the ATW-1800 wireless. If there are more than two people it feeds a separate Edirol R44 recorder and sync'd in post.

Cindy, our host, is also wired with the ATW-1800 in a studio.

Regarding range, the kayak story was done with the ATW-1800. I think that day I used the stock antenna. I got the half-wave antennas later.

YouTube - Hawaii Goes Fishing, Demo Reel 2010

The key lies in the FM noise as John says above. I rarely hear it on my Audio 2040's but you can if recording room tone and someone is banging next door. That sets off the breathy noise of the compander circuit somehow. Must be that FM noise again.[/QUOTE]

Yeah... breathing in the transition from silence to sound. The thing with FM audio is the is any phase noise in the reference oscillator for both RX and TX system contribute to noise..that and weak carriers aren't all too stable and we're dealing with low power sytems.

If I were to choose, (and money wasn't a concern) a digital spread spectrum system would be the way to go... Funny how the commodity electronic components available for this (think cheap wireless network cards) don't translate into lower prices - but I figure that wireless mike systems are a fairly vertical market...there's money to be made.

We *are* saying the same thing - just expressing it differently - unfortunately I got my 1:2 and 2:1 the wrong way round - sorry.