Conference napalm::commusic_v1

(1) How useful do folks find EQ in the studio?

    Very.  For going direct with electonic instruments, you can't use
    different mikes or play with mike placement to control tone.
    For things like taking bass guitar direct, it can smooth out freq
    response idiosyncracies, etc.  
    
(2) Do EQ units as a rule tend to be relatively "low-noise" circuits, or should
I be cautious about getting specs?
    
    I have something like the Marantz, 7 band stereo Rat Shack box I paid
    $30 for.  It's noisy.  But the noise comes into play mostly when you
    boost the upper frequencies.  If you're careful to boost only when
    absolutely necessary (i.e cutting one band rather than boosting six,
    eh?), they can be OK.  By comparison to my Ashley parametric EQ which
    is *really* quiet, there's no comparison. Rat Shack=$30, Ashley=$600. 
    You decide...
    
    Anyway, if you're talking about working with a $400 four-track
    cassette, it's probably useful.  If you're talking 24 track digital,
    well...
    
    
    							Brian

Thanks, Brian- this is kinda what I expected. I think I'll try to get the specs
out of the droids who answer the phone lines for the liquidator (it's C.O.M.B.,
BTW). They usually have some info on their computers.

You hit my setup exactly (just a tad more than $400, actually...): a four-track,
recording a combo of electronic and acoustic inputs. Now I just have to see what
kind of specs, if any, I can get. S/N ratios I've seen in my brief experience
range from ~55dB (noisy) to ~85dB (quiet). However, I haven't put anything
noisy "in the way" of the tape inputs just yet. Whattya guess is "acceptable"
for S/N? Is there any other metric I should scrutinize?

Your response implies that the noise contribution of the EQ is directly
proportional to the degree of boost invoked, right? Is the noise contribution
essentially nil when all sliders are set to midlevel, or is noise present for
any "non-zeroed" band? (I know the difference between passive and active EQ,
but I don't know squat about circuitry.)

Cheers,
	Bob

    The S/N ratio for a hi-fi EQ will usually be with the bands flat.  I
    think the RS box spec'd out at about 80 db, well, the hiss is audible
    if I boost more than 3 db at 6 or 10K.  Plus, any noise present in the
    input in that band also gets boosted.
    
    There's always *some* residual noise, but in *my* setup, the EQ is the
    least of my worries  8^)  8^)
    
    Expensive EQs go for noise-free filter circuits and also try to
    maintain phase integrity so as to not cause "smearing" of the sound due
    to phase shifts.  This required discrete designs.  Cheap EQs use IC
    chips, my RS has one for each channel.  The Marantz may use the same
    chips!!  
    
    							Brian	

Well, the phone-droids had no info, but I obtained the number for Marantz itself
and got some. As assumed, the unit's out of production- vintage circa 1989 or
so. Regarding specs, I was pleasantly surprised:

- Two stereo ins, two outs, both controlled by tape/source switch
- S/N 100 db
- THD .005%

The one thing it *doesn't* have is a defeat switch. Ah, well. Apart from that,
it sounds like a super deal for the price. With shipping, the total is $55;
two-year manufacturer's warrantee still holds. Thanks for the assists, Brian.
(FWIW, the Marantz ID is "EQ-432.")

Cheers,
	Bob

    
    s/n -100dB at -20dB with sliders at zero
    I'd bet -55dB at 0dB with sliders at +10dB 
    
    anyways it should be a useful tool and you can't beat the price
    
    have fun
    
    CdH
    

Well, EQ's on its way. Now as to hookup: seems I've got two major options, put
it in the effects loop of my 4-track or apply it to its monitor/main outputs.

My natural inclination would be to put it into the effects loop, where I can
apply it to each signal as desired; however, that *does* immortalize the EQ
impact on the media. All in all, I would guess that the advantages of individual
EQ of each track outweigh the disadvantages. Any comments?

(BTW, if/when I get some external effects, I would imagine they should be placed
in serial *after* the EQ unit in the effects loop. Am I on the right track?)

Cheers,
	Bob

    EQ should be patched into channel insert loops (if your mixer has them)
    or between the source signal and the mixer if what you want to do is EQ
    a particular input.
    
    For EQing a final mix, you patch between the mixer outs and the
    mastering deck.
    
    							Briabn

Looks like it's just you and me, Bri- thanks again for the input (pun intended).

I've got a Yamaha MT3X, which has no channel insert loops. I was kinda hoping
to avoid "telephone operator" syndrome, rearranging patch cords every time I
laid down a track, which is why I thought of using the effects send loop. On the
face of it, I don't understand *why* using the FX loop is a bad idea; can you
enlighten me?

Y'know, I always feel like I'm imposing when I ask a bunch of trivial questions
like this. Does anyone have a *good* recommendation for a book which covers
operation of "low-tech production" setups fairly well? I've seen several reviews
which identify books to *not* buy- I recall Brent Hurtig's, for instance, being
oe of them. The problems typically cited are that they are either oriented
toward professionally-equipped studios or at the "insert tab A into slot B"
level.

I have a funny feeling that the middle ground of "tolerable to half-decent"
studio setups doesn't represent enough of a market to warrant a good book. Sigh.

Cheers,
	Bob

    Thus is hard to do on an ASCII terminal, but:
    
    in                           out
    ------------|------|---------->
                |      |
                |----->|
    	          FX
    
    As (I hope) you can see, the FX loop is in *parallel* with the main
    signal.  It does NOT replace it.  So, what you get if you put the EQ in
    the loop is that you get some amount of "un-EQed" signal, and some EQed
    signal, mixed together.
    
    This is overly simplified but hopefullyyouare getting the idea. 
    Basically you want to *open* up the channel signal path and insert the
    EQ in line.  Without an insert loop, it can only be done by patching
    input-->EQ-->mixer or mixer-->EQ-->tape deck.
    
    
    						Brian

Scuse me for buttin in...

Depending on your equipment, you probably COULD put an EQ in an effects loop.
Certainly, it is electrically possible. Whether it really makes sense is
another issue. Typically, it does not. The method Brian posted is the more
traditional, and generally useful approach.

An effects loop picks of the signal from the main input signal, and
sends it out to some external device. Upon return, it typically comes back
prior to the stereo master fader, where it gets ADDED to the original signals
from the individual input faders.

In the typical mixer set-up for recording of mix-down, your original signal
will get added all other signals from the effects loop that are added onto
the effects bus.  With an EQ, you don't always want to boost, sometimes you want
to subtract from the original signal.  You can't when connected in a loop
unless you mixer has some way to defeat the sending of the original
signal to the master fader.  If you did that, then the EQ would be
fully functional in that it could either add or subtract, but then you
have lost much of the fuctionality of the channel. (ie channel fader, pan, 
somtimes channel EQ)

This loop set-up would work with my mixers, but I can't off hand think of 
a reason to  set-up in this manner, let alone have it as my standard set-up.
There may be exceptions, but I would reconfigure when they occur, and not
set things up standard that way.

It's kind of the same argument that you can have about compressors. They
don't do much in an effects loop, since their goal is to SUBTRACT from the
original signal. Things like reverbs, flangers, choruses ADD to the original
signal, and therefore make lots of sense in an effects loop.

It's not like that you can hurt anything bu setting up in the loop. Try it
by all means and convince yourself.

I put my compressors and EQ's in-line. I depend pretty much on the
channel EQ, unless I have a special application for EQ of an individual 
instrument. In that case, the EQ would go in-line, using an insert.

Hope this made sense.

I have a pretty good book on the subject. I believe that it is called
a "Guide for Home Recording". It is applicable to $1000 to $50000 studio's.
I'd give you more specific info on the book, but at the moment, I can't find it.

One thing that you want to learn about is impedence matching. Once you've
done that, you can figure out what works simply by hooking it up and
trying it.

Regards,
Rick

 

Thanks, Bri. Actually, I'd figured that part out, but thought it'd work pretty
well anyway- I figured it couldn't be any worse than always getting some "dry"
signal when adding FX. After due cogitation, I can see the difference- FX is
basically "adding" stuff, while EQ is "changing" it (i.e., boosting or cutting
*all* the stuff ina specified band). Oh well, it'll be sort of fun trying out
the possibilities. Thinking about how to use new toys ahead of time helps pass
the time while waiting for them to arrive...

Cheers,
	Bob

    re: .10
    
    > Depending on your equipment, you probably COULD put an EQ in an effects
    > loop. Certainly, it is electrically possible. Whether it really makes
    > sense is another issue. Typically, it does not.
    
    Rick, I think you are presuming that all effects loops are post-volume
    fader loops.
    
    If the MT3X effects send is the same as on my MT1X it is a pre-fader
    loop and thus can be used, with some limitations, for subtractive
    effects like EQ and compression.

Yo db-

Are you saying that I can zero the input sliders and independently control the
signal volume received from the FX send (i.e., the FX input is at its good ol'
prefader volume anyhoo)?

(We probably talked about this at one point or another, but things heard aren't
always things realized...things are beginning to clear through the mists...)

Yah, I know, I can go home and try it, BUT-

INQUIRING MINDS WANT TO KNOW!

(Right now!!!)

Bob

re: .12
  
>   Rick, I think you are presuming that all effects loops are post-volume
>   fader loops.

Perhaps I was. In fact I believe that most are probably pre-fader, with a
per-channel effect send amount. There are more likely difference's in
pre and post channel EQ, which may be a limiting factor.

>   If the MT3X effects send is the same as on my MT1X it is a pre-fader
>   loop and thus can be used, with some limitations, for subtractive
>   effects like EQ and compression.

 Okay, I agree.  My point was also that it COULD be done, but there were
 probably limitations, like whether you have channel EQ, channel pan etc.

 I guess in many ways's it is mixer specific, and how much sense it makes
 depends upon the features of the board.

 My particular board has a very good per channel EQ. I use my 10 band 
 graphic to contour the stereo outs, to compensate for room acoustics
 and speakers. I have never used it for recording. Maybe if I had it wired up
 in a loop, I would use it more for recording.

 But, I can't really use it for both, without moving wires.

 My second point was... experiment. You can't hurt anything I might even do that
 myself!

Rick

>Are you saying that I can zero the input sliders and independently control the
>signal volume received from the FX send (i.e., the FX input is at its good ol'
>prefader volume anyhoo)?
    
    I'm confused by your wording.  "The FX send" doesn't "receive" it's
    a "send".
    
    Let's put it this way: on MY MT1x the effects send controls for each
    channel are indpendent of the channel volume control.
    
    There's also a control that adjusts the level coming out of the
    effects send port (the combined input from all channels sending
    to the effect) and another control that controls the amount mixed
    back into the main stereo buss (from the return port).
    
    But I mentioned limitations:
    
    	1) You can't pan anything 
    
    	2) The MT3X track EQ may come AFTER the effects send rendering
    	   it useless.  I don't happen to know.
    
    	   Thus you may not be able to use the builtin EQ to give slightly
    	   different EQ between the tracks - something I could easily
    	   imagine wanting to do.
    
    Now my MT1x also has TAPE outputs for each track. 
    
    Those tape outputs could be used to create something not unlike
    inserts.
    
    On my unit, I believe I could take the tape output of track 2, run it
    through an efx processor, and then run the output of the efx processor
    into the input for mixer channel 2 and get something more or less
    equivalent to an insert.
    
    Note though that (like inserts) this wouldn't allow you to have
    two tracks share the same effects processor.  But that is the
    main difference between efx sends and inserts.