Sound system for a small school hall...

[Koldov]

Can you not get a simple Bluetooth dongle with a 3.5mm jack on it and plug it into a mixer? Something like this: https://www.amazon.co.uk/UGREEN-Bluetooth-Receiver-and-Transmitter/dp/B08TQSH636/ or this: https://www.amazon.co.uk/dp/B081GGB53R/

 

The range isn't going to be great but that's Bluetooth for you.

 

Unfortunately we don't have a great history with dongles, Powerpoint clickers, projector remotes. The idea is for it to be used with the 'big' speakers in the hall and remove the small active (classroom) speakers to have 'one sound system to rule them all'. At the moment the small speakers are plugged into a desktop at the front of the hall for 'presentation' and the big speakers are roughly in the middle attached to an ancient amp for louder music for disco/end of year leavers stuff. So I don't want to overcomplicate it by buying an amp/mixer/dongle, just want to make it simple... plug in, turn on.. sound...

 

Depending on space available, we've bought several of these:

 

https://www.amazon.co.uk/gp/product/B01MRY9KD9

 

Floor-standing (not rack mount), can be stood on a standard speaker mount, portable, includes battery, can take input from 3.5mm jack and Bluetooth, output can be sent into larger sound system, has two integrated wireless mics. We're finding they look a bit beaten up after 5 years or so of being hauled around the school, and the batteries now don't hold a usable charge, but if you want a handy all-in-one speaker / mixer unit plus a couple of wireless mics they're reasonably affordable. You should also be able to get replacement wireless mics for when teachers / children loose / eat them.

 

Yeah we have got a set of something similar to be hauled around the school/out onto the field for sports day, but they mainly stay with either the P.E. dept.

 

This needs to be 'rack' mount (old Hi-Fi cabinet) in the Hall and permanently attached (so nothing gets lost/moved/unplugged)...

[Andrew_C]

Guess it's not just me who'll randomly be asked for a bizzare quote that I know nothing about (e.g. moving flashing lights in the hall, or a "school app for the phone") only to get what I think they need and hear nothing again?

For our main hall a company came in and installed 4 XLR speakers, a mixer and amplifier, it wasn't cheap but they do full on productions here (comp school), only problem is out old system had some kind of pre-amp "phantom power" box that the laptop plugged into, which then plugged into the main mixer. This meant the main volume could be low so there is no hiss. But our new system doesn't have this; in order to connect a laptop we must turn the main volume up loud which hisses, and buzzes when the laptop is unplugged. Tried checking the mixer for a built-in version of this "phantom power" box but couldn't find one, it's all computerised though so I guess I missed something ?

Not 'phantom power' you need. You need a 'Direct Injection' box, which _may_ be powered by phantom from the mixer, or batteries. Some are passive.

[SamanthaD]

Sorry I'm coming to the conversation late!

 

Some general rules of thumb.

 

Audio systems are only as strong as the weakest link in the chain. Better to buy a full system of mid level components - an expensive mic will always sound rubbish through cheap speakers. This includes your cabling!

Amplifier power should exceed your speaker rating (usually double). Same as a car - you should have more enough power to drive at the speed limit without over-exertion, we call is headroom in audio terms. Driving your system at max all the time will increase the risk of distortion and overall wear.

I'm not going to name shame manufacturers here - but there are good options and less reputable ones. Do some homework on recent trends - I really rate some manufacturers who 10 years ago I wouldn't even consider.

 

So that all said - some direct points.

 

Bluetooth connectivity shouldn't be an integrated part of the amp. It really should be in the mixer stage, especially if you want to add microphones to it (talent show - pupil comes up with backing track on phone they need to control on stage and sing along with it). There's some good bluetooth dongles that terminate in an XLR - a band I worked with recently used one of these and I was quite impressed with it.

 

Laptops low volume issues - probably need a DI box. You can get specialised laptop ones with a 3.5mm cable already connected or the classic Behringer DI120 is pretty good.

 

Budget is the key driver here as always. I can spec you a £500 system or a £50K system. Until you know that anything else is pure conjecture!