Topic: Attenuator suggestions???

[mikesalvo]

looking to buy a pair. On a budget. What "flavor" should I buy. brand??? Anyone Anyone!?

thanks ya'll. tired of ruining recordings w/ hot board feeds!!!

[MattD]

I have a pair of like-new Sescom IL-24 20 dB XLR attenuators for sale. I bought them specifically for one thing and haven't used them since.

[jackmf]

I recommend the Sure A15AS for just that purpose, they're adjustable (-15, -20 or -25) and solid.

[flipp]

I'm very happy with the MPD attennuators from Naiant Studios. Doesn't hurt that John is also a member here and I prefer to patronize member vendors if at all possible.

http://www.naiant.com/studiostore/cleverdevices.html

[Simple Machines]

depends on the input plugs.  Shure 52A (I believe) are bulky but XLR.   Microphone MAdness makes one that is a 1/8" input plug.

[willndmb]

i have the mic madness one, its 1/8 on both ends, works good for my use of running from a board into a camcorder mic in

[OOK]

I have the AT8202 models from audio technica.  I absolutely love them.  They work fantastic.  I use them in high spl situations such as onstage recording.  AS far as I can tell they don't inpart any coloration on the sound they are recording, but then again my ears will be 39 years old next week.....

Peace   OOK

[wbrisette]

I have the AT8202 models from audio technica.  I absolutely love them.  They work fantastic.  I use them in high spl situations such as onstage recording.  AS far as I can tell they don't inpart any coloration on the sound they are recording, but then again my ears will be 39 years old next week.....

Peace   OOK

I'll second the AT8202 models. They are awesome. I own two sets, although is currently on loan. Since buying the Deva four years ago, I haven't had to use them because the Deva has built-in -25 to +30 dB incoming signal adjustment.

PM me and if you want a used set. I don't use any of them and I'll let a pair go.

Wayne

[animuselanvital]

Since this is kinda on topic. . . I own a pair of Earthworks (TC 30)  which have a frequency response of 9Hz - 30kHz. . . much broader frequency response than any of the XLR attenuator barrels that i have seen out there.  They typically seem to have a frequency response of 20Hz - 20 kHz which would crush the sound of the TC 30's.  Earthworks themselves sale one with a much greater frequency response but is a wopping $139!!!  Take that times two and it gets a little outrageous to say the least. . .  Anyone have any ideas?

[Roving Sign]

looking to buy a pair. On a budget. What "flavor" should I buy. brand??? Anyone Anyone!?

thanks ya'll. tired of ruining recordings w/ hot board feeds!!!

I seem to recall there is a difference between mic attenuators and line level attenuators...

[notlance]

Since this is kinda on topic. . . I own a pair of Earthworks (TC 30)  which have a frequency response of 9Hz - 30kHz. . . much broader frequency response than any of the XLR attenuator barrels that i have seen out there.  They typically seem to have a frequency response of 20Hz - 20 kHz which would crush the sound of the TC 30's.  Earthworks themselves sale one with a much greater frequency response but is a whopping $139!!!  Take that times two and it gets a little outrageous to say the least. . .  Anyone have any ideas?

Audio frequency attenuator circuits are quite simple and only use resistors.  Over the range of audio frequencies (and even over the extended range of 9 Hz to 30 kHz) the small wattage resistors used in attenuators are very linear.  Here is and example attenuator circuit:
        ---R1---+---R2---
                |
   -> Z1        R3      Z2 ->
                |
        ---R1---+---R2---               

R1 = ((Z1 + Z2)* 0.994 + (Z1 - Z2))/4

R2 = ((Z1 + Z2)* 0.994 - (Z1 - Z2))/4

R3 = (Z1 + Z2) / attenuation
Example: Z1=600 ohms Z2=600 ohms attenuation=317.3 (=50 dB)
Then R1=298 ohms, R2=298 ohms, R3=3.78 ohms

Unless some manufacturer threw in some capacitors and/or inductors into their attenuator circuit to intentionally limit its frequency range, any old mic attenuator should work fine.  You could just build one yourself; it's about a 1 beer project.

[animuselanvital]

Do you think I could fit 2. . . maybe 3 beers into that project without any adverse effects on the attenuator?   

It still begs the question as to why most of the commonly used attenuators out there list a frequency response range of 20Hz - 20kHz.
Some examples would be: Audio-Technica AT8202 and the Shure A15AS. . .

[notlance]

I think the manufacturers probably think 20 Hz to 20 kHz is a good enough range for the attenuator's intended use, but I guess you'd have to ask them.

The Audio-Technica AT8202 frequency response spec of 20 to 20 kHz is meaningless since they give no variation limits (i.e. +- x dB).  They could have just as well said its "frequency response" is DC to Light since the attenuator will respond in some fashion over that frequency range.

At least the Shure spec is meaningful since they spec the A15AS as 20 to 20 kHz +- 0.5 dB.  If that is not good enough, you can contact Shure and ask them what happens below 20 Hz and above 20 kHz, or you could get an A15AS and measure it yourself, or you can buy something else.

[DSatz]

animuselanvital, this type of attenuator is resistive, and its frequency response isn't limited to the audible range. The specification "20-20,000 Hz" is just to reassure people, since most people don't know Ohm's Law and are concerned only with performance in the audible range.

You evidently take the opposite meaning from those specifications, but that's a misunderstanding: The pad itself is audibly transparent except for the (desired) reduction that it causes in the strength of the signals.

There can be definite differences in quality among attenuators, however. The two series resistors in each "pad" must be very well matched to each other to maintain the balance of the circuit between the microphone and the recorder or preamp. If not, the input of the recorder or preamp will be subject to picking up hum, buzz or RFI from the cable. Fortunately it's not hard to measure that resistance, even without opening the pad's casing.

I've got half a dozen of the older Shure attenuators with fixed 15 dB attenuation; I measured them last year and found that they were remarkably consistent, and that the series resistors in them were extremely well matched. I now have a pair of the newer, switchable type as well, and will measure them, too, as soon as I get a chance, but I would expect them to be as they should be--Shure has always had serious, well-informed audio engineers designing its products.

--best regards

[animuselanvital]

Well, I sent both Shure and Audio Technica's tech support teams a message and here is what I received back in response to my question about their attenuators frequency response.

From Shure for the A15AS:
"We do not have an attenuator the meets your specifications."

From Audio Technica for the AT8202:
"Although I believe the circuit is capable of transparently passing frequencies below 20 Hz and above 20 kHz, we are only capable of accurately measuring the frequency response between 20 Hz and 20 kHz. Hope this helps."

Well, I guess I will give Audio Technica a try!

[SmokinJoe]

I know I have seen some little cheap thing like an extension cord with a volume control in it from Rad Shack or Walmart...  if you are running a board patch into the 1/8" jack on an iRiver, that should be fine.  here is one with a splitter in it... you get the idea.
http://www.radioshack.com/product/index.jsp?productId=3268770&retainProdsInSession=1&numProdsPerPage=60