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Radio Shack Volume Attenuator

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I guess I should wait for my MD to arrive before I start asking too many questions, thanks for clearing that up!

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I am in the UK, and only thinking about the possibilities of the headphone volume control. Mainly for it`s size.

Does anyone know if it`s a volume control as in having three connections. And wired across the live side of the mic. it`s centre going to the minidisk in put.

I built my own, and used it over the two year life of my Sony MZ R700. You need a capacitor wired from the centre to the minidisk in on both channels to stop the DC/plug in power from making the tracks noisy.

The cheap way is an in line variable resistor. Probably acting as a tone control.

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Does anyone know if it`s a volume control as in having three connections. And wired across the live side of the mic. it`s centre going to the minidisk in put.

You could get one from Maplin for 3 pounds and disassemble it to find out. I don't think it's a tone control--it seems to cut across the spectrum, not any frequency in particular. Despite all the worries here about noise, I don't get anything noticeable over the noise of a loud concert, and that's the only time I ever use the gizmo.

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I built my own, and used  it over the two year life of my Sony MZ R700. You need a capacitor wired from the centre to the minidisk in on both channels to stop the DC/plug in power from making the tracks noisy.

Huh? How can you afford that? Do you use unpowered dynamic microphones or self-powered electrets? Why do you think the 'plug in power' / bias voltage would make your recordings noisy?

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So the problem with the Line In is the extra track marks, nothing else (apart from needing a power source)?

We are recording mainly speech (my wife reads affirmations and other stuff which she then listens to when at vacation, some ambient music can be played in the background so there will be no track marks).

I'm looking for a cheap, but usable, mic that can be used for Line In. We have a normal mic that has been used for our N710/N910, but now that I have bought NH600 with only Line In we need a new mic so that we will not have to record to the old MD's and then copy to Hi-MD...

I first thought that something like this would be usable:

Powered Mic

...but then I read in the description that it's not really sensitive enough for use with Line In. Aren't there any mics at this reasonable price suitable for Line In? Remember, it's for speech and not live concerts...

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What you seem to want is a preamplifier / microphone combination. Either all-in-one or separate.

Here are some all-in-one solutions from soundpro:

http://www.soundprofessionals.com/cgi-bin/...tegory/165/mics

...and some external preamps:

http://www.soundprofessionals.com/cgi-bin/...tegory/540/mics

As you can see, it can get quite expensive if you have the need for an ext. preamp. Either using the 'old' equipment or upgrading to a HiMD unit with a built-in mic preamp should be considered alternatively.

Or you could try a somewhat experimental method: Using one of your older units only as a preamp, while actually recording with the NH600, using a 3.5mm stereo male-to-male cable going from the headphone output of the 'preamp MD' to the NH600's line input.

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Yes, I know about the preamps and how expensive they are considering my need to mainly record speech... I thought that there were something somewhat cheaper with lower audiophile standards...

If I want to use one of the NetMD's as a preamp, do I need it to record to a disc at the same time or will it always send a monitoring signal out on the headphone output?

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Quote

Huh? How can you afford that? Do you use unpowered dynamic microphones or self-powered electrets? Why do you think the 'plug in power' / bias voltage would make your recordings noisy?

Greenmachine.

A stereo pot £1.50, one stereo 3.5m jack socket and plug @ 99p each, two small capacitors 40p and make a small metal box. I use self powered electrets.

Not expensive maybe more bulky. But better quality. Probably not necessary with the NH700, because there are several choices of input level control.

Plug in power is about 2.8volts DC. load resistors are built into the minidisk, and connect directly to the electret capsule.

DC flowing through the volume control will cause the track to wear and become noisy. Look at any amplifier circuit, and there will be a DC blocking capacitor at one of the volume control connections.

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If I want to use one of the NetMD's as a preamp, do I need it to record to a disc at the same time or will it always send a monitoring signal out on the headphone output?

You need to set it to rec pause (with a disc inserted) to get a signal. Recording is not necessary.

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Hi, first post here and I would like to take the opportunity to thank everybody for the great information that I found here on the forum. thumbsup.gif

Beside that, does anybody know if this attenuator (or some kind of equivalent) is available in Europe, beside the U.K.? It's not possible to us, Europeans, to order at RadioShack and probably the shipping-/handling-costs from the USA to Europe will be as high as the price of attenuator itself...

I'm from the Netherlands and searched for it at Google, but couldn't find anything.

Anyone?

Greetz,

MadMaster, Amsterdam

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The only way to tell if the control on a pair of cheap headphones would work is to try it: buy them, chop off the headphones and replace them with a jack.

But it's not for the headphones. It's not to adjust volume. It's a buffer between the mic and the mic preamp. It just happens to work.

Whether or not you have Radio Shack or Maplin, there must be some store that sells electronic gadgets. Don't look for an attenuator--look for a headphone volume control.

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Thank you, but i guess people want to use an attenuator instead of a battery box, which is theoretically a bad idea but seems to work to a certain degree. There's no real use for an attenuator - battery box combo if you have mic- and line inputs on the recorder, you can use the mics with a battery box directly to line-in instead of attenuating the signal and preamplifying again.

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Originally written by forum user [and owner of Reactive Sounds] Reactive.

---------

The radio shack volume attenuator

I use this with a MZ-R700 You have to for loud music w/ this unit -- as with the 900 poor mic pre amps -- but the problem I find, it that the wheel on the attenuator doesn't have any markings on it. So, I go from a pretty loud show to a really loud show, I have to guess where to set it. I've ended up making marks on the wheel with white out, little dots, so I (Kind of) know where I was previously... Lame really.

Does anyone know of a wheele like attenuator/in-line volume control, like the Radio Shack one that has numbers on the wheel ?

This would be a godsend - then, if someone could make a lighted version...

Thos

Thank you, but i guess people want to use an attenuator instead of a battery box, which is theoretically a bad idea but seems to work to a certain degree. There's no real use for an attenuator - battery box combo if you have mic- and line inputs on the recorder, you can use the mics with a battery box directly to line-in instead of attenuating the signal and preamplifying again.

Actually, this is untrue -- I have a battery box made by a Canadian company called Visivox, and it has a high and low gain on it. There are times when the high gain is too much, and the low... you get the idea. So, some times, and attenuated high gain can bring you just above a low gain, etc...

I've used it to some slight success -- the problem I find, is that monitoring the signal with the headphones while recording (Shure EC3 w/ ear plug sponge) doesn't demonstrate the saturation (if it is over) of the signal. I use the wheel to cut back the amount of signal, then the input gain (recording level) of the MD to compensate. If you filter too mush w/ the attenuator, like if at a really loud show, close to speakers (at least w/ the sony) then you bost to where it needs to be w/ the recording level, and end up sucking in a lot of hiss with it -- because there isn't enough signal.

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My noobie question is, is it worth using the Radio Shack Volume Attenuator if I'm recording live music at an outdoor venue as opposed to an arena or club? I'm on a limited budget right now and Bike Week is just around the corner. One of the Harley dealerships here in Florida has a lot of good acts playing for free. My stealth rig right now consists of: SP-BMC-2 > Sony MZ-RH910(mic in). Any input will be greatly appreciated.

Edited by argie1971

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Somehow I don't think the Harley dealership is going to be presenting a string quartet.

Unless you use an attenuator ($7) into Mic-In or a battery module ($60) into Line-in, you will overload the mic preamp and have unlistenable recordings. Guaranteed. Bring along your headphones and try recording the opening act straight into Mic-in and you'll see what I mean.

Usually I suggest leaving the volume control on the attenuator all the way up, but if it's really blasting you might want to turn the attenuator down partway. You should still try to keep your distance from the woofers if the music is really loud. Bass overloads the preamp first--the attenuator prevents that--but if it's loud enough to overload the mics themselves, you'll still get distortion.

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GM you bring up some good points. One of the reasons why we Church Audio do not use a potentiometer in the input stage of the mic, before an active preamp is simple, while you are infact reducing the input level, you are reducing the BIAS voltage at the same time :) Thus increasing the distortion by starving the FET of its needed supply voltage. LESS bias voltage = more distortion = bad sound. In some cases you can use this and " get away with it". Here is another problem the headphone attenuator. It is designed for HI level signals, not low level signals of a electret capsule. So it is unsheilded because RF and EMI induction is not a problem with a hi level signal. It becomes a big problem with low level signals like the ones comming from a microphone. Thus it will increase the noise floor of your mics in some situations like a concert this might not be a problem. But if you have attenuated too much and have to normalize the crap out of a signal via a computer You will hear that noise.

Chris Church

That's not the main reason for increased noise, basically you lower the signal from the microphone while the noise of the preamplifier stays the same -> lower Signal to Noise Ratio. Even if you have perfect contacts, the SNR will decrease.

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We've gone around and around on this theoretical discussion. I'm sure you mic builders are technically correct. But n00bs can listen to the attenuator recordings in my Album under Live Recordings and see what you think of them. It's a cheap, practical solution.

For earsplitting or earthquake-level-bass music, microphone to battery module to line-in is best. Attenuator may work but can't prevent mic overload.

For moderately loud music, microphone to battery module to line-in can be too quiet, needing amplification that also amplifies noise. I consider it a toss-up between that and mic--attentuator--mic-in. This is getting away with it, technically, but since you can get away with it, why not?

For quiet, non-bass-heavy sounds, mic straight into mic-in is best. For ultra-quiet sounds, perhaps an outboard preamp into line-in is a good idea, but I've found that an outboard preamp (I've tried both Reactive Sounds and Sound Professionals) clips at levels so low that it's no use to me.

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I just bought one of the RS Attenuators. I sat my Mini disk in front of my Carvin MTS Half stack and recorded with the Attenuator at 50% and without crunched at about 3.5 on the volume. WOW sounded like a big F#@t without and was clean and clear with :ok: !! Thanks for this tip guys we run the FOH at my church at about 105db ( with 4000 in attendance and over 1500 of them SCREAMING teens it takes that at the least to be heard over the CROWD ) and I was getting substantial clipping with my MZ-R70 and stereo Panasonic mic set up at the sound booth( see attachment here [attachmentid=1537] from last sundays service as an example) . I can`t wait to try this on Sunday ;)B) !!

3_12_06_COC_Better_Than_Life_.mp3

Edited by Shreadhead

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It depends on volume and mic sensitivity, but you may not need to turn the attenuator down that far.

For anything but the kind of megabass that makes your eardrums feel like they're imploding, I leave mine on max and just watch the levels on the MD. Just putting the headphone volume control between mic and MD does some attenuation anyway. You can also get noise when you turn the volume knob on the attenuator, so best to just set it and leave it alone, at whatever level you decide to use.

Glad it's helping you.

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It depends on volume and mic sensitivity, but you may not need to turn the attenuator down that far.

For anything but the kind of megabass that makes your eardrums feel like they're imploding, I leave mine on max and just watch the levels on the MD. Just putting the headphone volume control between mic and MD does some attenuation anyway. You can also get noise when you turn the volume knob on the attenuator, so best to just set it and leave it alone, at whatever level you decide to use.

Glad it's helping you.

The system at my home church has some SERIOUS bottom end thunder so I will need some attenuation for shure. This test was a worst case situation and it handled it well.I have to guess on the actual record levels as I am on stage playing when the full band is going. I will let you know how it turns out after tomorow.

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