Attenuating Mic Pres w/o Output Level Controls

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promesis

promesis

Black Knights of the 4H.
what if I need to attenuate the signal out of the external pres .. as it is now:
Mics going straight into the Mackie Board, a couple of mics send pretty hot signals even with their -10 pad engaged and the Mackie input channel trim fully ccw, I still need to drop the faders a few dB to keep from clipping the recorder :eek: The RNPs do not have an output level .. I am thinking about getting a couple of Mecenary Audio's racked RNPs/RNCs
http://www.mercenary.com/2rnhoinfulof.html
Given this scenerio, with the RNC connected to the inserts of its companion RNP, would it be advisable to maybe use the Gain settings of the RNC to attenuate the levels going into the recorder? Or is there a different and better way of attaining this, almost assured necessary, level attenuation since I would rather by-pass the board all together when the pres are purchased?

Thanks for your time.
 
What kind of mics do you have that are sending hotter than line-level????? (which is what has to be occurring if you have the pre trims all the way off....)
:eek:
 
I am using (2) AT4033s between racked toms... I could use some SM57s but experimenting a bit, I found that the AT4033s give me a pretty crisp attack with really full lows... along with pretty nice "bleed" from the whole kit. If I need to switch Mics .. so be it .. however, I am interested in the addressing "attenuation dilemma" if only conceptually.
 
Yeh, hot mics on loud sources...
AT makes a 8202 3-position mic level pad that passes phantom that I use on QTC-1's feeding the A/D directly. 'Earthworks clain they top out at around 10 volts max. :rolleyes: The issue comes up again with a True Precesion 8 pre with dynamics on kick and snare- min 15 dB gain at the pre, and it needs a 15 dB pad on the output. Silly really.
You should be able to toss gain at the RNC insert though.
Make sure the A/D is set min. sensitivity too.
Wayne
 
I use the AT4033 and it does NOT put out a hot signal - certainly nowhere near line-level, as your initial post describes. I use the 4033 on drum sources too and engaging the 10dB pad on the mic works perfectly!

Something is wrong with your signal chain, or you've set something incorrectly. Describe in detail all the gozintas/gozoutas from the source to the recorder, and maybe I can help track it down... what you said initially doesn't really make sense, if you're using the 4033!!
 
Most Mackie boards give +10db at the mic input with the trim knob all the way down. The RNP starts at 0 db. This may be enough to help you keep your levels under control.
 
boingoman said:
Most Mackie boards give +10db at the mic input with the trim knob all the way down.
Click to expand...
Funny - I never noticed that on the 8-buss when I had it... mind you, I rarely used the on-board pres, so there ya go!
 
my set up is :
(2) AT4033s about 5" above racked toms with the -10dB pad engaged
Into tracks 5 and 6 on Mackie 32x8 board
Trim of each channel set to full ccw ** which is in fact +4dB (pg 1 of Manual "Important Sensitivty Adjustment Procedure")
EQ section unengaged or just very slight EQ with the section engaged
Channel Faders set at Unity ("0")
Direct Outs of these (and all channels) into the Inputs of Alesis HD24.

Maybe I should clarify some info here .. since I simply may be attempting to have my equipment set in certain ways without understanding the "dynamics" of some of the controllers or situations involved.. for example: I am a stickler for setting up proper levels into the Mackie .. with regard to the aforementioned "Sensitivy Adjustment Procedure". The Manual says with "solo" engaged, set the Channel Faders to "Unity" then adjust the "Trim" pot to optimize levels by setting peaks .. etc etc .. Mackie Users know what this procedure is.. no problem. Levels set well .. absolutely no "OL" peaks on the channel or the Main Fader Level Meters.. I have, I hope, set levels correctly within the tolerances the Mackie engineers had hoped I would.

So here is my scenerio and "thought process signal chain" :
While tracking once in a while the red "clip" led gets lit on the HD24 .. ** granted none of the channels are clipping constantly .. just every now and then the 0dB (red led "clip" on the HD24 lights up .. ) no clips or "OL" on the Mackie .. and honestly I don't really hear any "nasty digital distortion" during playback of these sections.. but in my "bone head by the manual brain" .. "IT CLIPPED ... OH NO!!" .. and since the Mackie manual tells me that the clip or "OL" indicators light up a few dB lower than the actual clipping level and the HD24 Manual has no such "level caveat" .. I may only assume that "clip" on the HD24 is indeed "clip". Ok .. so I then attenuate the Channel Faders on the Mackie to tame the offending signals.. but now I have compromised the optimal levels from the board ** or is this my error in understanding ** am I simply missing out on the concept of Level Setting on the Mackie? That is to say (or write) that the "trim" pot on the Mackie is actually setting the optimal internal setting of the board and the Channel Faders are simply the Output level of each Direct Out .. so attenuating these fader levels into the recorder is not really compromising the optimal levels of the board (but well hey .. maybe even expected) .. the more I explain this .. the more I realize that this is probably the case. But the Manual does not explicitly say this in the "Level Setting Procedures" .. but "duh" I guess it is a "no brainer" .. but for some reason I was expecting that the HD24 would just accept the optimal "Unity" fader setting uncompromised .. ok .. well at least set me straight on this.. ** then ..
if this is the case .. and using the Faders all ding dong day to set levels into the HD24 is "ok" and well just kinda josh darned "expected" .. back to my original question :
If I get the RNP/RNC rack set up and bypass the Board all together .. I have then bypassed the "Faders" that are, conceptually the "Output" level of the Mackie's Mic Pre Amp .. since the RNP has no such attenuating Output level .. what can I do .. but "duh" .. it does have its input level .. I would hope then that setting up the RNP's optimum input level would not "clip" the HD24's inputs .. but who knows? .. Since the RNP's Gain control starts at 0db and not +4dB like the Mackie, it looks like (correct me if I am wrong .. and please be patient with me .. I am trying to learn as much as I can about doing things right and being correct in my impressions) .. there should be no problem. If needed, I could still attenuate the RNP's inserted RNC's output levels to set the Input levels of the HD24.

Well .. please set me straight and correct and/or affirm my conclusions, thought processes and identify my misunderstandings .. I appreciate everybody's time, attention and experience. It really helps to actually flesh this out by writing and analyzing things as I attempt to convey my problems or concerns .. maybe I answered all of my own questions .. I dunno .. I can't be afraid to ask .. lest I remain ignorant.

Thanks again for your time and attention!
 
When you go through the setting levels procedure, you only need to worry about setting the trim. (like you have) Set the fader so it doesn't clip the HD24. The trim sets the level that the board will see, the fader sets the level that the recorder will see. As long as you have good signal at the input of everything in the chain, you will be OK. The reason you can clip the recorder without seeing a clip light on the Mackie is because the Mackie has more headroom than the recorder. They don't clip at the same level.
 
When I used the Mackie 24-8, I would run the outboard pre outputs directly into the HD24 without any problem. The pre's I'd use would include RNPs, APIs, GR and Phoenix..... for drum overheads, I almost always would engage the pad on the mic, and often engage the pad onboard the APIs as well, depending on the drummer, because there could be some seriously peaking transients depending on the playing and the style of music.

Following that procedure, I never had difficulty interfacing with the HD24.

If you have to use the Mackie pres, then I would consider taking the insert outputs and sending them directly to the recorder. This way, you're bypassing all unnecesary circuits (EQ, faders, etc...) Naturally, this won't work if you need the onboard EQ though.......
 
Thanks for the clarification Fairview.. :rolleyes:

Blue Bear Sound said:
... I almost always would engage the pad on the mic, and often engage the pad onboard the APIs as well, depending on the drummer, because there could be some seriously peaking transients depending on the playing and the style of music.

Following that procedure, I never had difficulty interfacing with the HD24.

If you have to use the Mackie pres, then I would consider taking the insert outputs and sending them directly to the recorder. This way, you're bypassing all unnecesary circuits (EQ, faders, etc...) Naturally, this won't work if you need the onboard EQ though.......
Click to expand...

Ok .. yeah I dig it .. but in my situation I'd really like to try and bypass the whole Mackie board pre section and go right into the HD24 as you have described.. the EQ is not really an issue since I spend a lot of time on placement / drum tuning and only affect the eq minimally .. (the only reason I do is so when I mix I can expect a pretty nice sound with eqs flat and concentrate on levels and effects .. and any eq if needed would be quite minimal).

Do the Gain settings on the RNP, starting at 0db, give me the "padding" I would need since I expect those peaking transients .. i.e. given the current model of attenuating the Mackie Faders and a dynamic hard hitting drummer?

thanks again.
 
With the RNP you set your gain so that you don't see the clip light and you'll be fine!
 
Blue Bear Sound said:
With the RNP you set your gain so that you don't see the clip light and you'll be fine!
Click to expand...

Thanks .. I am so fortunate .. you seemed to be very familiar with the exact kind of set up : AT4033s on drums.. RNP.. Mackie .. HD24 .. if I may, can I impose upon you still for some more advice:

With the RNP/RCP rackmounts available thru Mercenary .. what is your experience with the compressor in this chain .. I usually do not compress going to the recorder, however, with the aforementioned RCP/RNC rack scheme, it would seem their idea would be to utilize the special insert relationship between the two units to compress "to recorder" -
1. would you compress going "to tape" in this manner or would I be better suited to not avail myself to this and bypass the RNC during recording and utilize it during mixdown via channel inserts.

2. Also, once you have gone to the recorder thru the RNP .. it is done right? .. there is no useful purpose for it during mixdown .. I would simply mix down as I have using the Tape Returns from the HD24 and insert whatever serial devices (RNC if not used during tracking) and utilize the channel's EQ and Aux send sections... right? Am I getting there?

3. Of course, if there were a time where I could totally bypass the input section of the Mackie channel by "tapping or muting the mic pres" via the channel's insert circuit .. I should definitely do so .. correct ..? as per the concept of not pushing signal thru more "filters' and circuits if not needed... then I could insert the compressor and effects i.e. reverbs, flanges etc. directly .. (that is if I have enough outboard gear to accommodate this).

What are your experiences, impressions and advice in these matters?
Thanks again..
 
Hmm, if I did the math right, it would take 148dBSPL (which exceeds the AT4033's rating) to clip the HD24 input (+19dBu) with a AT4033 (94dBSPL = -29dBu) with the 10dB pad engaged:

-29dBu - 10dB pad + 4dB gain = -35dBu

94dBSPL + 35dB (above) + 19dB (headroom) = 148dBSPL

Which is about 130dBSPL at the drummer's ear.

Food for thought.
 
mshilarious said:
Hmm, if I did the math right, it would take 148dBSPL (which exceeds the AT4033's rating) to clip the HD24 input (+19dBu) with a AT4033 (94dBSPL = -29dBu) with the 10dB pad engaged:

-29dBu - 10dB pad + 4dB gain = -35dBu

94dBSPL + 35dB (above) + 19dB (headroom) = 148dBSPL

Which is about 130dBSPL at the drummer's ear.

Food for thought.
Click to expand...

No wonder my drummer wears earplugs.
 
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