Category Archives: Public Address

Philips / Bosch Repairs

With the decision by Bosch to no longer support the older conference microphones, Digital Congress Network (DCN) systems, clients have reported being advised that there are no more parts available to repair the LBB 3546 delegate unit directly from Bosch. We at AVD are happy to advise that we have a large number of these units suitable for being ‘broken’ and recycled for spare parts.

LBB 3546

If you send us your non functioning unit we can repair and return the unit for £100 + Vat and shipping. The repair will consist of the straight swapping of the mother board or any other component requiring a repair.

In times of limited budgets and with many councils and organisations feeling the squeeze it makes sense to try and maintain these systems for another couple of years at least.

The donor units are from a large well maintained system which we recently replaced due to the uncertainty introduced by the Bosch decision. If you have a system which is missing a few units or are considering replacing your system then we can help in maintaining what you currently have as well as advising you on the disposal of your old system and any new replacement you may consider.

AVD are  an independent supplier and have equipment from Bosch, Televic, DIS and Brähler in our own rental stocks.

We have recently sold recycled system components to clients in Poland, Germany, Ireland as well as in the UK.

Please contact us to find out more.

What is a discussion microphone? Part 2

What is a discussion microphone? How is it different from a conventional microphone?  Part 2. Mark Kisby continues his explanation… (missed Part 1? click here)

Conference, discussion or ‘push to talk’ microphones provide the best conference audio solution for speech reinforcement. Though sometimes not the best in absolute sound quality, it is the ability for the microphone to be controlled by both delegate and sound technician that ensures every word is heard.

Boardroom discussion microphones

Discussion microphones set for a boardroom style conference

For this reason conference microphones are particularly suited to the recording of meetings, councils and parliaments and the provision of the ‘original’ feed to a simultaneous interpretation system.

In these applications the aims is to have as few microphones ‘live’ or ‘on’ at any one time, each ‘live’ microphone adds more back ground noise to the audio feed.

The standard operation of a sound desk with just 6 conventional microphones on a top table is to leave all 6 microphones live (but set to a low volume) so if someone does speak the technician need only increase the level of a microphone. This allows at least some audio, albeit low level to begin with, to be heard which is better than nothing. This is because the technician does not know who is going to speak next and the speaker is unable to make their microphone live independently of the technician. There are two main reasons why this is not acceptable in a recording or for simultaneous interpretation.

Firstly the delay in a delegate speaking and in the microphone becoming live, as the technician recognises which microphone is in use and increases its level,  introduces a pause into which whole sentences can disappear and critical meaning can be lost. Conference microphones can be operated by the speaker directly so eliminating this delay in making the microphone live or louder. This allows a freer flow of dialogue to take place without a word being lost. This is critical in the recording of important meetings and in the original language feed for simultaneous interpreters.

Secondly by having so many partially live microphones live you are introducing unwanted and distracting background noise into the audio. This is often not recognised by the delegates or by the technician who generally listen to the audio via the PA in the room where these noises are already present. However other users, e.g. interpreters, listen to the proceedings via headphones so they are very ‘close’ to the audio and can clearly hear the rustle of paper or the pouring of water. This unwanted audio is very distracting and can mask important elements of the speech.

With a conference microphone system you have the capability to control and help eliminate these spurious sounds without losing the critical audio by only having one or two microphones live at any one time.

The other added advantage is that it is possible for a system to extend to include  10 – 100 – 1000 participants so making the discussion microphone ideal for use in council chambers, parliaments and general meeting rooms.

The advantages in using discussion microphones or discussion systems are very clear (especially the audio!).

Portable PA chimes at bells protest

Staff at AV Department can from time to time borrow equipment from the company’s inventory. Normally this a PA for a party or a projector over Christmas but a recent protest in Burntisland saw the MD Mark Kisby make use of the unique qualities of an Anchor Audio MegaVox portable PA. Mark tells the story…

I live in Burntisland, a small coastal town on the shores of the Firth of Forth just north of Edinburgh. Its town clock has chimed on the hour, and quarter hour, for the last 150 years. It rings to the throbbing heart of the community and living within close earshot of the bells it marks the passage of time in our home.  Then recently they suddenly stopped?

It transpired a complaint had been made that they where too loud so the Fife council silenced the bells after one complaint in 150 years. Reaction from the townsfolk was initially incredulous but a petition was organised, to show the feeling of the residents, collecting 1100 signatures. With the coming of the New Year and the fact the town clock would not be ringing in 2011 a protest was also organised proclaiming that ‘Hogmanay had been cancelled!’ Protesters were to bring a bell and chime their wish to have the clock bells re-instated.

Feeling strongly that the bells should return I wanted to take part in the protest but found myself without a bell! Now a person of my problem solving skills should be able to over come this little matter. A quick search of the Apple app store revealed a bell application aptly named ‘bells’. This turned my ipod touch into a whole peel of different bells but an ipod is not loud enough in a crowd so I borrowed an Anchor Audio MegaVox portable PA from our hire stock. This battery powered PA is designed for out side use in large crowds… and for a hand help system it is very loud!

So the time came to show our displeasure at the silencing of the bells by ringing ours… as I chimed it sounded like the bells had been miraculously re-instated! Fellow protesters turned round to see who had managed to lug a church bell down the road… It gave the protest a bit of volume which seemed to be appreciated by the 200 strong crowd.

Our little protest made national news the following day as a topical human interest story. Here is how the BBC web site covered the story.

The MegaVox has now been returned to the warehouse ready for use at the next protest…