Rackmount wireless microphone set

[dhicks]

Hello All,

 

Our school has been needing a new set of half-decent wireless microphones for a while now, and I've just come accross these on eBay:

 

CHORD QU4 QUAD UHF WIRELESS HANDHELD MIC MICROPHONE SYSTEM 19" Rack Mountable | eBay

 

The Chord QU4 would seem to be a rack-mountable 4 microphone set (available as handhelds, headsets, or a mixture of both - I'm assuming we could also buy a set of handhelds and get four extra headsets, just as long as we didn't try and use both sets at once). It seems to work on the unregulated Channel 70 frequencies, so should be legal to use with no license required in the UK, and looks like a generally nice, compact, well-thought-out bit of equipment. Obviously you can't tell exactly what the wireless range and sound quality for those microphones is going to be just from a picture, but we only need something of reasonable quality for a school.

 

Has anyone come accross Chord microphones before, does anyone have one of these sets, are they okay?

[dubbish]

CHORD are a cheap copy type brand that will try and make anything

[dhicks]

CHORD are a cheap copy type brand that will try and make anything

 

Do they generally seem to make stuff okay? Looking around a bit, there seems to be several brands using similar technology - W Audio's TPT-202 Twin UHF Handheld Mic System looks okay, too, although you have to buy two base units to cover 4 microphones. We don't need stunningly good quality equipment here - we're a primary school, at some point a small child is going to loose / drop / eat parts of whatever equipment we buy, basic functionality will be fine. Looking at that eBay posting above, that firm actually has a shop in Croydon - I could probably go and give the unit a test before I buy.

[dubbish]

don't get me wrong they do seem to make some equipment of fair good quality but I would just be unsure of any wireless equipment that they make

[CESIL]

We have recently got one of these Quad setups and so far they seem pretty good...I have been able to go quite a long way down the corridor outside the hall and still get reception.

 

The microphones are a bit susceptible to noises while being handled but the switch can be flicked onto mute very easily to avoid this while passing it to another person.

 

The only thing I think may be a weak point is that they use replaceable batteries rather than rechargeables and I expect the time will come that someone plans to use them but doesn't check the batteries until milliseconds before they need them...

[dhicks]

We have recently got one of these Quad setups and so far they seem pretty good...I have been able to go quite a long way down the corridor outside the hall and still get reception.

 

Thanks, good to know.

 

The only thing I think may be a weak point is that they use replaceable batteries rather than rechargeables and I expect the time will come that someone plans to use them but doesn't check the batteries until milliseconds before they need them...

 

I've got that covered - I have batteries stashed in the cabinet I store the microphones in, made up into sealed two-battery packs. You put new batteries in at the start of an event and chuck them away when done - it's a bit heavy on batteries, but means you're always using new batteries.

[soveryapt]

For my basic AV setup, I have an Ashton AWM400 Quad Channel Receiver System which works well (I've bought a mix of belt pack and hand held devices to go with it).

 

The main issue you run into with such devices is frequency interpolation in that the shared antenna aren't totally up to the job in all cases .. eventually I want to replace my 4 way unit with separates, but for basics it does the job ..

[dhicks]

The Chord QU4 would seem to be a rack-mountable 4 microphone set

 

Right, this has just arrived this morning. It's actually a decent, solid-looking bit of equipment, and I've now got the unit set up in our audio rack. We've had a test of the microphones' range (one of the caretakers walked down the hall with a mic, speaking as he went) and ability to all function at the same time (me and the caretakers did a quick spot of barbershop quartet style harmonizing). It works fine with the "mix" output plugged straight into the amp, but when I try and plug either the mix or an individual mic channel into the audio desk any speech comes out barely audible. Do I need a mic pre-amp, and if so what's going to be the best (and cheapest) rack-mountable option?

[soveryapt]

Right, this has just arrived this morning. It's actually a decent, solid-looking bit of equipment, and I've now got the unit set up in our audio rack. We've had a test of the microphones' range (one of the caretakers walked down the hall with a mic, speaking as he went) and ability to all function at the same time (me and the caretakers did a quick spot of barbershop quartet style harmonizing). It works fine with the "mix" output plugged straight into the amp, but when I try and plug either the mix or an individual mic channel into the audio desk any speech comes out barely audible. Do I need a mic pre-amp, and if so what's going to be the best (and cheapest) rack-mountable option?

 

What desk do you have? Most audio desks have pre-amps / gains built in. Check you don't have a PAD pressed in which will reduce the input level, or make sure your gains are turned up as well as the faders.

[dhicks]

What desk do you have?

 

An early ninties (20 years old) Soundcraft Spirit Folio F1 - actually, now I come to Google for it, I've just found a PDF of the user manual, which should come in handy.

 

Most audio desks have pre-amps / gains built in. Check you don't have a PAD pressed in which will reduce the input level, or make sure your gains are turned up as well as the faders.

 

Thanks, I'll check the manual and see if it has a built-in pre-amp. There's no "PAD" button, but there are some buttons labelled "PFL". Gain on the mic receiver and mixing desk is turned right up.

[Andrew_C]

The Folio does have Mic inputs. Make sure you are connecting to the XLRs and not the jacks. You may need jk-xlr leads depending on the output connector on the receiver.

[soveryapt]

An early ninties (20 years old) Soundcraft Spirit Folio F1 - actually, now I come to Google for it, I've just found a PDF of the user manual, which should come in handy.

 

 

 

Thanks, I'll check the manual and see if it has a built-in pre-amp. There's no "PAD" button, but there are some buttons labelled "PFL". Gain on the mic receiver and mixing desk is turned right up.

 

PFL is Pre Fader Listen - basically means you can check input on a channel before it hits the fader - useful for finding where the annoying squeal is, or for using the EQ to set mics etc.

 

Anyway, the F1 desk does have gains to the top of each channel (Grey Knob with Red on it if I recall) - used to work with one on a smaller PA rig I managed. Best thing to do is plug a set of headphones in, plug the mics in, then press the PFL, and see if you get anything out, if not, turn the gain knob up until you do.

 

If you're getting something out there, then check that the routing on the F1 (hang on, going to Google is to remind myself ... right) is set to go to the right place - so the smaller desks go pretty much straight to the master, if it's a larger desk, you might need to depress a button labelled LR to get it through (probably also buttons marked 1-2, 3-4, etc if this is the case) then it should go straight to master.

 

Then double check your wiring is going from the right output on the desk to the amp etc.

 

If you don't get anything, it could be the desk has seen it's best, but they are quite solid workhorses to be fair.

[dhicks]

The Folio does have Mic inputs. Make sure you are connecting to the XLRs and not the jacks. You may need jk-xlr leads depending on the output connector on the receiver.

 

I've tried both types of cable (XLR and mono phono jacks). The microphone unit has 5 outputs - one XLR for each single microphone channel and a mono phono jack output for a mix of all 4 microphones.

[Andrew_C]

Should be XLR-XLR in that case.

 

Is there an option to alter the output level on the receiver? Set to 0db if you can.

Edited June 6, 2013 by Andrew_C

[dhicks]

Anyway, the F1 desk does have gains to the top of each channel (Grey Knob with Red on it if I recall)

 

Yep, I've given that a good twiddle. If I put the gain on the mixer right up and turn the volume on the microphone to full then I can get a signal through the sound desk, it's just very distorted and not very loud. When I plug the mixed output from the microphone unit straight into the amp then the signal is just fine, although it could be a bit louder. I have a small 4-channel sound desk at home, I could try putting the microphones through that to see if it sorts the problem.

[dhicks]

Should be XLR-XLR in that case.

 

Could the problem be crummy cables? We have some rather old-looking cables, and most are rather longer than they need to be just to connect bits of equipment together, might that be at least part of the problem?

 

Is there an option to alter the output level on the receiver? Set to 0db if you can.

 

All four mic channels are cranked right up - I don't think they're lablled in decibels, they're just plain twiddly knobs.

[soveryapt]

I've tried both types of cable (XLR and mono phono jacks). The microphone unit has 5 outputs - one XLR for each single microphone channel and a mono phono jack output for a mix of all 4 microphones.

 

Have you tried just the mix or just a single channel? I think if you plug them all in then you might hit issues, I may be wrong, but my ashton only likes either the mix or the separates being used. In terms of the output on the receivers, again if it's like my ashton, there will be a volume control on each channel that you change using the up and down buttons but it won't be meaningful numbers as such, simply a range (I think mine is 0-60 so I generally have them set at 45).

 

I would chase through my suggestions about if you're still not getting anywhere. If you plug the mics in and press the PFL button on that channel, does the the LED strip light up at all on the top right of the Folio? As the PFL will switch that main mix monitor to being a specific channel monitor. If you're getting lights, then sound is hitting the desk and the issue lies somewhere after that (so either the outputs as described above or possibly the connection between the desk and the amps).

[Andrew_C]

Cables could be the problem if they aren't wired "normally" Should be pin1-1 pin2-2 pin3-3 and NO connection to the shell. It does sound like something may be mis-wired and grounding incorrectly.

[Avonics]

May be worth just checking that the cables you are using are microphone cables and not speaker cables. Could have same connectors but are different cable and connections.

Speaker cable only have two cores and no screen. Pop the XLR open and see if the cable looks like two core mains flex.

[Avonics]

Have knocked up this image as a guide. I have looked at the manufactures images and it looks like the XLR outputs are mic level rather than line. So they should work into the folio.

You can always check it by plugging a handheld wired microphone in.

In fact that would also check the cables and prove if they are OK.

[dhicks]

but when I try and plug either the mix or an individual mic channel into the audio desk any speech comes out barely audible.

 

The problem seems to have been our Bose 802c Series II controller. This conked out completly this morning, so I bypassed it and plugged the mixer desk straight into the amp. We can now plug the mic output into the mixing desk, which seems to work fine. We'll have to wait and see what the sound quality is like without the controller for the speakers.

[Andrew_C]

Ooopps... It was fine when I last used it, honest!

 

Not having is won't cause any damage unless you are running flat out, when you could overdrive at some frequencies. It will affect the sound though; you could tweak to improve if you have a graphic equalizer.

Edited June 19, 2013 by Andrew_C

[soveryapt]

Yeah, you're better off (if you can) buying a new controller if you plan to use it in anger at any stage or (worse still) allow other staff who aren't techy savvy make use of it - unless you can make use of gaffa to limit the output from your desk etc - ok, they could remove the gaffa, but if you put a nice note "so as not to damage the PA system whilst we source a new controller, please do not use above the gaffa line" etc ..

[dhicks]

Ooopps... It was fine when I last used it, honest!

 

We've had a good year's use out of it, we really can't complain!

 

Not having is won't cause any damage unless you are running flat out, when you could overdrive at some frequencies.

 

Right now, the equipment is being used for the junior school fashion show in the church hall opposite - if there's a sudden loud bang, I'll know what happened.

 

It will affect the sound though; you could tweak to improve if you have a graphic equalizer.

 

I think maybe our graphic equalizer was part of the problem before - I don't know what I'm doing with one well enough to be able to set one up, and they always get fiddled with anyway, which made speech through those speakers come out very odd-sounding. I'm going to try the system later with a DVD, see if it's intelligable.

[Chris_]

I've never come across a Bose controller being used with 802's. You should be fine without it. I'd personally buy new speakers instead of replacing the Bose controller.