Legacy microphone connectors

Right. I wasn't aware there was a Reslo style mating line connector, since I've never seen one. But since it obviously exists all you can do is keep an eye on Ebay for one, as I'd guess its obsolete, like so many of these. However, the option is simply to replace the cable - this will also have the benefit of cutting down on the total number of connectors which is always best practice.

If it's a fairly permanent installation where the cable doesn't get moved much, you can save money by using cable designed for installation rather than stage work.

Reply to
Dave Plowman (News)
Loading thread data ...

I understand the concept of what you are suggesting but I'm not sure, other than looking at cost, what it means in practice. Maplin has been suggested on here ie

formatting link

but I would hope we could get away with a lower cost than that. Mono recording - some sites have had success with unscreened lengths - though one site reported some background sound that turned out to be a French radio station!

I'm afraid I don't understand some terms and concepts in use - balanced, impedance matching etc. We are talking fairly basic clean recording, no clipping, not oversensitive to frequency response, semi-fixed internal installation, not studio or stage.

Reply to
AnthonyL

You'll pay through the nose for cut length cables - and from Maplin - and for a 'name' like Van Damme.

Mono or stereo makes no difference as regards mics - except that mono only needs one circuit.

As regards using unscreened, it might work ok. But might not. Unscreened used to be common for line level signals which are perhaps 50dB higher than mic level.

You don't need to understand much of that. The main difference between a stage and installation cable is the stage one will be more flexible and better protected from physical damage. So more expensive.

I'd be inclined to use star quad which has the best protection from unwanted signals of all.

CPC do a low cost one - 60.50 inc VAT for 100 metres, post included. Or ordinary twin screened for about half that. CB13301

Reply to
Dave Plowman (News)

Unbalanced cable has a centre core and an outer shield. Both are used to carry the signal. Balanced cable has two cores, used for the signal, and an outer shield which is earthed but is not connected to either side of the microphone/amplifier, hence the three pins (two signal plus shield) on an XLR connector. This makes balanced cable less prone to picking up interference. I discovered to my cost how much interference a long run of screened but unbalanced cable can pick up when I was videoing my sister's wedding: I bought a long length of cable to connect the camcorder to a mike on the table for the speeches and discovered with about an hour's notice that something in the room was generating horrendous amounts of interference, which hadn't occurred when I'd tested the setup at home. Luckily it only happened when the camcorder was plugged into the mains, so I during the meal I hastily recharged the battery I'd just used for filming the ceremony and ran the camcorder off the battery.

Impedance matching means that the impedance (effectively the resistance) of the microphone must be similar to that of the amplifier input. In practice this means that a low-impedance mike such as a moving coil must be connected to a low-impedance amplifier input; if you connect a high-impedance mike such as a crystal to a low-impedance input you tend to get a low signal and one which is very tinny because the low frequencies get attenuated more. Some mikes have a transformer which matches a high-impedance mike element to a lower impedance amplifier input.

Reply to
NY

Just got this as a result of browsing Amazon:

formatting link

What can go wrong?

Reply to
AnthonyL

Probably ok. As cables go twin screened for microphone use isn't a terribly demanding spec.

But that price is no better than some of CPC's offerings. And they are a long established UK firm with quick free delivery.

Reply to
Dave Plowman (News)

In article , AnthonyL scribeth thus

Seems to me you've done more then you should with this character. You've had some good advice from here from people who have worked in pro audio and recording and yet this duffer doesn't want a pair of modern day well proven connectors in his ancient cable;!..

As to that go to CPC rather then Grablins and do use balanced working and do earth the screen as in such locations those Cables make damm good aerials;!!.

Bin there dun that and heard the interference. Use a matching transformer input if the equipment doesn't have one that might help alleviate that from coming a problem...

Reply to
tony sayer

Yes I've had a closer look at CPC. Used to find Farnell's (has it always been CPC-Farnell or is that a merger?) a tad expensive when I was doing IT as are Maplins on the whole.

I remember I've got a couple of reels of Cat5 - left over from a wiring job. Might just give that a go first.

Whilst I appreciate there has been good technical expertise on here some of the solutions are way over the top. Basic dynamic mics using unscreened cable on modest digital recorders have worked for this requirement or

formatting link

We are not the BBC!

Reply to
AnthonyL

CPC are generally very good value these days as they include free delivery. Maplin used to be reasonable value for small orders of electronics when the larger firms had a minimum charge - but Maplin seem no longer interested in that side of the market.

Fine if you are prepared for the possible consequences.

It will depend on your standards. You gave the impression you were interested in decent quality. Good microphones ain't cheap - and having the recording ruined by a passing taxi using its radio due to using the wrong cable may not matter either.

Bit cheaper than Maplin, then?

When it comes to getting the cleanest possible recording of anything, the rules don't change. Regardless of who you are.

Reply to
Dave Plowman (News)

In article , AnthonyL scribeth thus

Yes they Farnell are slightly different to CPC but essentially the same..

Well it will more likely that not work but I suspect that if you do want to get external "noise" problems than thats a good way to go about it.

Will work fine at "Line" levels tho..

And more often then not we've been asked to sort those out!, fine over a few feet most of the time but much longer;(..

Thats premises wiring cable prolly the other more might work better for what you intend..

No, I can only suppose you don't have the BBC's unique way of funding;!...

Reply to
tony sayer

OK but this is a fairly special situation rather than standard recording for broadcast/replay.

Once in place it will be pretty well permanent and not in areas of general access. I could put a more flexible on the jack plug end.

Reply to
AnthonyL

How you record it has nothing to do with the quality of the signal getting to the recorder.

You've been advised by those who know about such things how to cable a balanced mic to any recorder. If you choose to ignore such advice why bother asking?

Reply to
Dave Plowman (News)

In message , AnthonyL writes: []

Unbalanced - usually something like coaxial cable where the signal is grounded on one side (sometimes at both ends, i. e. the screen of the cable is attached to something earthy at both ends, sometimes not [the actual source, i. e. the microphone in this case, has to have both its sides attached of course]). Relies on the integrity of the screen - at all frequencies - to resist pickup. Unbalanced - both sides of the signal are sent by as near as possible identical wires, in the hope that any pickup will be the same on both, and you can subtract one from the other, leaving just the wanted signal. The two are not of course always identical though, either in routing or series resistance etcetera. You can also get balanced cable that has an additional screen round both. Balanced/unbalanced also tend to have different impedances.

Impedance matching: mainly, if you're not impedance matched, you won't get the maximum power possible out of the source, so the wanted signal is smaller relative to anything unwanted that might be picked up; also, any such mismatch is likely to not be linear across the frequency band of interest, so you get tinny or boomy. You can always sort this out afterwards if not catastrophic - in theory you always could, but it's easier nowadays - but better not to throw away quality in part of the band in the first place if you can avoid it.

Clipping - that's just going to be a matter of choosing an appropriately-rated input stage, I don't think the cable is likely to affect it. Although for something like church bells, overloading of the microphone itself needs to be assessed - not usually what clipping is taken to mean, but hitting endstops is hitting endstops, whether they're mechanical or electrical.

The main effect of whether it's fixed or not is that you can get away with less flexible cable for the fixed parts - which can be cheaper, or better electrically, or some compromise/combination - though if it becomes a matter of fixed for part of the run and flexible for the last bit, that means more connectors, which isn't good.

Reply to
J. P. Gilliver (John)

In message , NY writes: []

It's expressed in ohms, but isn't a resistance you can measure with a d. c. resistance meter (often this _will_ give a valid answer, but not for some types of equipment, and not if there's any series capacitor).

There's also the characteristic impedance of the cable; for short runs not too important, and I'm out of my knowledge area here but I would think that for something like mic. level signals over 100' or so, it probably _does_ matter. (And that's _not_ one you can measure with a multimeter - the easiest way is to look at the catalogue you're buying it from.)

Sometimes you find installations where transformers are used at both ends of the cable, though I've heard of this less in audio than in mains power distribution, and less recently I think than it used to be.

Reply to
J. P. Gilliver (John)

All balance mics are roughly similar in this respect - so using cable designed for this job should ensure it's ok. And it's not like it costs a fortune.

Other point I forgot to make is running a cable up a church spire makes a pretty good aerial. So all the more need to use decent stuff to minimise the effects of RF pickup.

For very long runs - or where a poor cable *must* be used - the correct way is to add a mic pre-amp close to the mic and send 'down the line' at a higher level.

Reply to
Dave Plowman (News)

That last sentence should have started "Balanced - both sides ...".

Reply to
Jeremy Nicoll - news posts

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.