Depends on several things:How big is the amplifier (in watts)?
What are you ‘tapping’ the speakers at?
If we assume that the cable run is no more than 300M from amplifier to last speaker then cable can be 1mm standard 2 core flex. After that it is a simple case of maths – if you have a 60 watt amplifier you would generally want to leave 20% headroom, in an ideal case, which leaves you 48 Watts of load available. A typical example is shown below:
PC-1868 – (can be tapped at 6/3/2/1W) – at 6 Watts you can fit 48/6 = 8 x speakers , tapped at 3 watts you can fit 16 speakers and so on.
This example can be applied to any 100V loudspeaker, you just have to know what the taps of each speaker are.
And YES you can have many different types of speaker (ceiling, horn, wall, cabinet etc.) all on the same amplifier.
Generally 2 core stranded. Simple answer is to include a table such as:
This really needs a photo of the back of an SC-615M and explain – they normally arrive ‘out of the box’ at their maximum tap setting so it is important to adjust the tap before the speaker is installed…
Example – anSC-615M has15W /10W /5W /3Wtap options, in impedance this relates to 666Ω / 1KΩ / 2KΩ / 3.3KΩ The basic maths for this is P=V2/R or R=V2/P
So R (impedance)= 1002/power in watts: 2000Ω = 10000/5watts
(V is the 100V line constant so is always 10000 in the UK)
Specific questions for VM-2000 series:
5 general plus ALERT & EVAC
The VM-2000 system as a whole has a cable distance of 800M – this is the distance from the first microphone to the amplifier and out to the last amplifier. So if you have 1 x VM2240 then the RM-200 can be 800M away – although you would need to power the RM-200M locally with a PSU (AD-4800 or AD-246).
YES -this will duck anything connected to the BGM inputs.
The VM-2000 series amplifier is a fairly complex amplifier – with this in mind it is vital that the installation manual be studied prior to any site visit where one or more of these amplifiers is to be installed.
Specific questions related to A-1700 series.
This is an odd one, it works via a simple contact closure but if the amplifier is ON the contact closure will turn it off. But if it’s OFF the contact closure will turn it ON!!
Specific questions related to A-1800 series.
Yes & No. You have to remember that both the 1700 & 1800 series only have 1 amplifier channel internally. It does however have 2 x speaker zones which can only be selected via the front of the amplifier. These switches turn the speaker outputs at the back on and off. The direct out is not affected by these buttons.