Suggested frequency map for 16 Sennheiser G3/G4 radio mics on Channel 38

[spotblaster]

Our theatre has a channel 38 radio mic licence and 8 Sennheiser G3 radio mic channels all on the inbuilt first block of frequencies. We have successfully hired in an additional 4 Sennheiser G4 channels and set them to the remaining channels in that block.

For the next production "Company" I am being asked for 15 channels of radio mics and my instinct is to go for 16 so that we have a spare channel. That would be 8 G3's and 8 G4's.

I have seen a reference somewhere that it is possible to use up to 16 channels within channel 38 but I cannot find a suggested frequency map.

Can anyone help me with this please?

Many Thanks

 

David Ashton

[Stuart91]

Here's a link to Sennheiser's frequency charts. 

The GB range is the one you want to look at - I've pasted it in as an image below. 

You won't get 16 into Ch38 itself, as you can see they spill over onto Ch39 and upwards. 

EW100 sets will tune to the full range, they just don't have built in presets beyond the first 12 so need to be tuned manually. 

If you want to stay within your licence, it's best to hire a set of four in either Ch70, or the space around 832MHz. 

[cedd]

What Stuart said. 16 is asking too much. You need to be looking at an alternative band. You should have channel 65 as part of your channel 38 licence. This would be my preference, followed by channel 70. Other options from different brands include VHF and 2.4GHz. 

[spotblaster]

Thank you for the advice.

It seems I misunderstood the maximum number of slots in channel 38 which looking at the frequency chart is 13 if we use bank 7, 9,11 or 12 rather than the bank 1 we are using at the moment for which the maximum is 12.

I must admit I had forgotten about channel 65 and the 2014 published Sennheiser chart predates it - the changes having been made in 2015.

We can access some older G3 units that will tune down to 830Mhz. Sennheiser list three slots in the gap between 830Mhz and 832Mhz. If I can get that to work I have achieved my 15 plus a spare and my Director is happy.

Thanks again for pointing me in the right direction.

David Ashton

[TomHoward]

Do most E-range Sennheisers go down to Ch65, and is there a preset that uses 65 & 70? Or are the two sets of presets far enough away you can run 4 in 65 and 4 in 70 alongside the 12 in ch38 shared licence?

I have the same problem of a rack of 12x Ch38 and needed circu an additional 4 to hire or purchase

[Stuart91]

22 hours ago, TomHoward said:

Do most E-range Sennheisers go down to Ch65, and is there a preset that uses 65 & 70? Or are the two sets of presets far enough away you can run 4 in 65 and 4 in 70 alongside the 12 in ch38 shared licence?

I can't speak for radio mics, but have used IEMs in both 65 + 70 simultaneously without any issues. (A mixture of G2 on Ch70 and G3 on Ch65, four in each space)

 

[ninjadingle]

Can you just apply to Ofcom for an additional license for the duration of the run? I think that would be easier (and cheaper) than trying to source specific equipment that works in a particular frequency band?

[TomHoward]

Looking at ofcom ch41 is also available in our area - the chart above tells you not to mix banks, but presumably that means when the same channel appears in two banks ? I assume you can run bank 1 (ch38) and bank 2 (ch41) simultaneously? 

[DavePallant]

You should not mix banks because the frequencies within each bank are calculated with no other banks in use. For example using banks 1 and 2 in the table further up (bank 1 is channel 38, bank 2 is channel 39) will mean that the sidebands from Bank 1 might interfere with Bank 2. You need to choose a single bank where you can get the number of frequencies you need. For example if you need 16 then you could use bank 6, 7, 8, 9 or 13 or 14 all of which have more than 12 frequencies. Alternatively finding some E band systems (823-832MHz and 865ish MHz) might be easier.

[TomHoward]

Thanks all,
We've found 4x Ew300 G2 E-band systems.... unfortunately they're 830-865 so can use them in 863-865 Ch70 but not the 823-832 Ch65 of the shared microphone licence.... they don't seem to go low enough and guess we'd need G3-Es for that.

 

[kgallen]

@TomHoward You can do at least 7 with EW G2 using Ch70 and Ch66 830-832MHz shared:

If you don't mind foresaking the 3TxIM(3) then you can get 8 (which I use quite happily for AmDram). You'll need to programme up the user ('U') bank for the ones that aren't preprogrammed in Bank 8.

830.000, 830.400, 830.900, 831.300, 863.100 (B8/1), 863.500 (B8/2), 864.100, 864.900 (B8/4)

 

Edited November 3, 2023 by kgallen

[chelgrian]

On 11/1/2023 at 11:06 AM, DavePallant said:

You should not mix banks because the frequencies within each bank are calculated with no other banks in use. For example using banks 1 and 2 in the table further up (bank 1 is channel 38, bank 2 is channel 39) will mean that the sidebands from Bank 1 might interfere with Bank 2. You need to choose a single bank where you can get the number of frequencies you need. For example if you need 16 then you could use bank 6, 7, 8, 9 or 13 or 14 all of which have more than 12 frequencies. Alternatively finding some E band systems (823-832MHz and 865ish MHz) might be easier.

In general when doing anything involving multiple ranges you just ignore the banks entirely and input what frequency ranges you have available in to the WSM software and ask it to produce you a frequency plot. For older mics you'd then have to tune the user bank manually if you have G3 300 or better you can transfer from WSM via Ethernet.