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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: Kevin Maxwell on March 25, 2016, 11:47:51 PM

Title: Sennheiser EW100g2 2 questions.
Post by: Kevin Maxwell on March 25, 2016, 11:47:51 PM
Sennheiser EW100g2 2 questions.

I was doing some work on a sound system in a church today and they started a rehearsal as I was packing up and I noticed that the 4 EW100g2 that they were using (as vocal mics) with 835 heads didn’t sound right so I went up on stage and looked at the receivers. All 4 were being over driven. I mentioned this to the music minister who said if he drops the sensitivity on the transmitters they don’t sound right. So the question I have is there a tonal difference if the sensitivity is reduced on the Sennheiser EW100G2 mics, other then maybe a little closer to the noise floor. Or do you just have to make up the gain at the console.   

The other question I have relates to frequency selection. I ran the frequencies that they were using against the Database in Shure WWB6 and of the 9 wireless that they have only 3 came up as no conflict the other 6 were incompatible frequencies. And I didn’t have a chance to scan the environment with my WinRadio. So I don’t know if there is anything more in the air then what the Database lookup says there is. I have been doing frequency coordination for so long that I haven’t experienced what happens when it isn’t done properly. So to the question, is it possibly that there would be audible effects other than them stepping on each other to the point of them not working if they aren’t tuned (coordinated) properly? And what would that sound like.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Henry Cohen on March 26, 2016, 10:43:05 AM
I was doing some work on a sound system in a church today and they started a rehearsal as I was packing up and I noticed that the 4 EW100g2 that they were using (as vocal mics) with 835 heads didn’t sound right so I went up on stage and looked at the receivers. All 4 were being over driven. I mentioned this to the music minister who said if he drops the sensitivity on the transmitters they don’t sound right. So the question I have is there a tonal difference if the sensitivity is reduced on the Sennheiser EW100G2 mics, other then maybe a little closer to the noise floor. Or do you just have to make up the gain at the console.

Sensitivity is a function of the receiver, not the transmitter. With FM systems, signal strength does not affect volume or tonality of the audio. Too weak an RF signal at the receiver can certainly result in noisy audio, but the underlying audio will have the same relative volume level and frequency response.  Conversely, too strong a signal overloading the receiver front end can also result in noisy, distorted and/or no audio, depending upon how the receiver front end and demodulator circuit react under saturation conditions.

Transmitter mic input gain should be adjusted [obviously] to the highest level possible but below that which overloads the preamp. At the receiver, the output audio level control, if provided, should be set to match the level (mic vs. line) expected by the next input device (typically the console), and the gain control (again, if provided) set to the highest level that neither overloads the receiver's output driver or the next device's input stage.


Quote
The other question I have relates to frequency selection. I ran the frequencies that they were using against the Database in Shure WWB6 and of the 9 wireless that they have only 3 came up as no conflict the other 6 were incompatible frequencies. And I didn’t have a chance to scan the environment with my WinRadio. So I don’t know if there is anything more in the air then what the Database lookup says there is. I have been doing frequency coordination for so long that I haven’t experienced what happens when it isn’t done properly. So to the question, is it possibly that there would be audible effects other than them stepping on each other to the point of them not working if they aren’t tuned (coordinated) properly? And what would that sound like.

If the uncoordinated frequencies in use has an IM product(s) falling within the occupied channel bandwidth of one of the frequencies, but at the far edges (around 100-200kHz from the tuned frequency), I could imagine the resulting audio distortion could possibly have tonality changes given audio frequencies subtracting/combining somewhere in the demodulating or audio output stage. It might also be the interference induced noise mixing with audio.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Kevin Maxwell on March 26, 2016, 01:06:44 PM
Sensitivity is a function of the receiver, not the transmitter. With FM systems, signal strength does not affect volume or tonality of the audio. Too weak an RF signal at the receiver can certainly result in noisy audio, but the underlying audio will have the same relative volume level and frequency response.  Conversely, too strong a signal overloading the receiver front end can also result in noisy, distorted and/or no audio, depending upon how the receiver front end and demodulator circuit react under saturation conditions.

Transmitter mic input gain should be adjusted [obviously] to the highest level possible but below that which overloads the preamp. At the receiver, the output audio level control, if provided, should be set to match the level (mic vs. line) expected by the next input device (typically the console), and the gain control (again, if provided) set to the highest level that neither overloads the receiver's output driver or the next device's input stage.


If the uncoordinated frequencies in use has an IM product(s) falling within the occupied channel bandwidth of one of the frequencies, but at the far edges (around 100-200kHz from the tuned frequency), I could imagine the resulting audio distortion could possibly have tonality changes given audio frequencies subtracting/combining somewhere in the demodulating or audio output stage. It might also be the interference induced noise mixing with audio.

Thank you for the response and help.

On the Sennheiser EW100G2 transmitters the menu uses the term SENSIT. On the receiver it has AF OUT.
Following is a cut and paste from the EW100G2 instructions for use.
“Adjusting the sensitivity (transmitters only)
SENSIT Via the “SENSIT” menu, you can adjust the modulation level of the transmitters.
This changes the transmitter’s input sensitivity.”
So that is why I used the term Input sensitivity for what on other systems is referred to as input gain.

These mics sounded to me like it was clipping the preamp in the transmitter and when I looked at the receivers on stage and saw that they were hitting the peak pretty hard and consistently I brought it to the attention of the Music Minister. And after his response of “if he drops the sensitivity on the transmitters they don’t sound right” made me wonder if he likes it crunchy. At the moment I am tired of trying to convince people of how to properly set there systems. I also can’t understand why people use a relatively cheap wireless when the people singing aren’t moving around and most of the time the mic never leaves the mic stand. I try to tell people how much better it can sound to spend even less on a good quality mic then on a cheap wireless. I guess they just want a few less wires on stage. Or they think it looks cooler or is it the “everyone else is doing it” mentality. 

The uncoordinated frequencies information is helpful also. At this place I think I will retune the wireless and let it go at that.

The way I like to do that in general is to scan the environment (with the WinRadio) with no transmitters on to see what is out there in the air. And then import that into Shure’s WWB6 and enter the Zip Code or coordinates. I have been using 30 miles as the distance to look out to. And then have it give me a few extra channels to use if they want to add some more mics. And then I retune the wireless to the recommended frequencies. Does this sound like a good way to do this? Or is there a better way?
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Tim McCulloch on March 27, 2016, 12:41:29 PM
I also can’t understand why people use a relatively cheap wireless when the people singing aren’t moving around and most of the time the mic never leaves the mic stand. I try to tell people how much better it can sound to spend even less on a good quality mic then on a cheap wireless. I guess they just want a few less wires on stage. Or they think it looks cooler or is it the “everyone else is doing it” mentality.

Quick anecdote:  a couple years ago we did a food-centric "fest" with lots of live music.  By mid afternoon the stage was packed full of back line gear (radio station promo act wanted star treatement for their 30 min segment) and we set 2 wired mics at the DSR corner for the Emcees.  The festival person demanded to know why we didn't provide wireless mics for them.  I pointed out there was literally nowhere for the emcees to go - there was nowhere on stage they could walk without running into a musician or gear.  She was nonplussed.  "They're radio people!"  "They're standing in one spot and can't move" we reply.  Ms Festival Person relented when I told her it would add $150 to her boss's bill.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Ray Aberle on March 29, 2016, 11:04:22 AM
You've said it before; "Customers don't make silly requests; customers give you another opportunity to add a line item to the invoice." Still, stories like this make me giggle.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Tim McCulloch on March 29, 2016, 03:32:42 PM
You've said it before; "Customers don't make silly requests; customers give you another opportunity to add a line item to the invoice." Still, stories like this make me giggle.

They were already over budget because the festival didn't tell the radio stations that artists riders were subject to "festival stage plot".  The acts insisted on a number of accommodations that the festival just rolled over to give them, even though the festival had no say in who the radio stations brought in or what their needs/wants were.

This event went 3 years before the promoter (venue management) pulled the plug because the entertainment expenses exceeded the costs of the food portion.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Rob Spence on March 29, 2016, 06:48:55 PM
Back on the topic title.... I was looking for a couple of Sennheiser manuals for a G2 mic receiver and I believe a G1 IEM transmitter, both 300 series but I could only find G3 manuals on their web site.

I need to program the "U" band/group so they talk to each other for cable less access through a wall.


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Title: Re: Sennheiser EW100g2 2 questions.
Post by: Kevin Maxwell on March 29, 2016, 11:25:12 PM
Back on the topic title.... I was looking for a couple of Sennheiser manuals for a G2 mic receiver and I believe a G1 IEM transmitter, both 300 series but I could only find G3 manuals on their web site.

I need to program the "U" band/group so they talk to each other for cable less access through a wall.


Sent from my iPad using Tapatalk HD
What information do you need? I have the PDFs of the EW100 first generation and the EW100 G2 if you want me to email then to you I can. But it really should just be a matter of tuning them to the same frequency. I am pretty sure they didn’t add the pilot tone till the G3. If I can help at all let me know exactly what you need.
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Rob Spence on March 30, 2016, 12:25:41 AM
What information do you need? I have the PDFs of the EW100 first generation and the EW100 G2 if you want me to email then to you I can. But it really should just be a matter of tuning them to the same frequency. I am pretty sure they didn’t add the pilot tone till the G3. If I can help at all let me know exactly what you need.

Thanks
I have a ew100 and a sr300
I would like manuals to read. All my other wireless is Shure and the Senn terms in the menus are different as well as the button actions.

So, since there are no presets for either device that are compatible I need to roll my own. I am supposing that the best bet is to use presets in the transmitter as they are likely planned to not inter fear with wireless mic use and simply tune the receiver to match.




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Title: Re: Sennheiser EW100g2 2 questions.
Post by: Kevin Maxwell on March 30, 2016, 09:44:40 AM
Thanks
I have a ew100 and a sr300
I would like manuals to read. All my other wireless is Shure and the Senn terms in the menus are different as well as the button actions.

So, since there are no presets for either device that are compatible I need to roll my own. I am supposing that the best bet is to use presets in the transmitter as they are likely planned to not inter fear with wireless mic use and simply tune the receiver to match.




Sent from my iPad using Tapatalk HD

I wouldn’t even worry about using their presets because they aren’t usually compatible when using multiple wireless systems.
If you want, I will then check out the compatibility of what you have and give you a recommended frequency to tune this wireless to. To do this I will need you to send me a list of the brands and models and bands of the wireless systems you will be using in this environment and the band that this pair you want to use is in. Also please send me the frequencies that everything is now tuned to and the specifics (brand, model and band) of those systems so I can see if they can stay the same or what needs to be retuned. Also I need the zip code of the location. It is also possible (I really should say probable) that if what you have in this location is already set to the groups that Sennheiser has listed in there docs, that what you already have isn’t compatible when a proper frequency coordination is done. Since I am not there to scan your environment I won’t know if there is something else in the air that could interfere that won’t show up in the Zip code lookup. I would also recommend that you tell me how many more channels of wireless you might want to add in the future either permanently or temporarily. I would need all of the same information for them, brand model and band. And I will see what looks like it should work. I have found for me it is much easier to account for possible additions then it is to try and squeeze them in later.

Also with the changes of the frequencies where TV stations are transmitting on and new stuff coming on line you can’t count on the frequencies that were set a while ago not having potential problems. I coordinated a churches wireless systems about 2 years ago and did it again recently and discovered a new TV station nearby is now on the air and could interfere with their systems without retuning them.

I emailed Rob this with the PDF files for the G1 and G2 systems. For other peoples benefit I am also going to post this on the forum.   
Title: Re: Sennheiser EW100g2 2 questions.
Post by: Kevin Maxwell on March 30, 2016, 11:19:17 AM
FYI to add - I just tried in Shure Wireless WorkBench6  (WWB6) to see if the 20 channels Sennheiser has listed in band A bank 1 were compatible.   First I just tried to see if I could get 20 channels in band A. keep in mind that in WWB6 there are 3 options when coordinating frequencies. Robust, Standard and More Frequencies. I always try to get what I need using Standard. In standard I could only get 14 compatible frequencies. In Robust I could get 13 channels compatible, in Standard I got 14 and in More Frequencies I got all 20. So I decided to try and see what would happen if I tried to do even more channels. And I was able to get 30 channels that are supposed to be compatible. But this is all without figuring in any TV channels or anything else that would most likely interfere.   

So next I entered all of the 20 frequencies listed in band A bank 1 into WWB6 and the results really surprised me. In Standard mode NONE of the frequencies were compatible with each other. And this is without entering anything else, no TV stations, just checking them to each other.  In More Frequencies mode I got that 6 of them were compatible. This is using a list that I have found is the same for the G2 in a publication from them from 2004 and one from 2013.