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Conference napalm::guitar

Title:GUITARnotes - Where Every Note has Emotion
Notice:Discussion of the finer stringed instruments
Moderator:KDX200::COOPER
Created:Thu Aug 14 1986
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:3280
Total number of notes:61432

891.0. "EQs" by CSC32::G_HOUSE (Back in Black) Wed Oct 05 1988 22:39

    Here's another (probably stupid) question.  Is there a difference
    between a graphic EQ designed and sold for use as a stereo componant
    and those sold for use with musical instruments (other than cosmetics)? 
    
    The reason I ask is that the used musical equipment market locally is
    pretty sparse (and rather expensive).  However, due to the close
    proximity of fairly large military bases, there is an absolutely HUGE
    market of used audio equipment...
    
    Greg
T.RTitleUserPersonal
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891.1there are differancesANT::SDRP_JACQUESThu Oct 06 1988 10:5816
    
    There are differences. The obvious differance is that stereo EQ's
    have RCA phono inputs and outputs. Pro gear generally has both
    1/4" phone jacks and balanced XLR jacks, although some of the
    pro gear designed for recording use do have RCA phono jacks. Pro 
    units are designed to operate at 1v line levels, and have balanced
    transmition lines. Balanced outputs are very important on a pro
    unit so you can drive the signal from the sound board back to the
    stage where the power amps are located. Stereo gear is meant to 
    operate at lower voltages than 1v line level, therefore you could
    end up overdriving the inputs of a stereo EQ. I would say, if you
    are doing some home recording on a Multi-tracker, a home stereo
    EQ would be usable, however for PA use it would not do as good a
    job.
    
    Mark
891.2re.1 Can you answer a couple for me?VOLKS::RYENRick Ryen 285-6248Thu Oct 06 1988 13:4925
re: < Note 891.1 by ANT::SDRP_JACQUES >

	Mark, 

	You sound knowledgable. Can you answer a few questions for me?

	>>>"Pro gear generally has both
	    1/4" phone jacks and balanced XLR jacks..."

	Could you briefly explain to the terms balanced outputs 
	and balanced transmission lines? Can I assume that anything 
	that has a 2 conductor XLR connector is balanced?
	Can I assume that 1/4" is unbalanced? How do I decide when
	to use one over another?

	>>>"Balanced outputs are very important on a pro
	unit so you can drive the signal from the sound board back to the
	stage where the power amps are located. "

	The set-up I work with occasionally, has the power amps set up at
	the board, sending the high power signal to speakers on stage
	over 1/4" lines. Is it better to send the low voltage signal
	on balanced lines, with the power amps on stage? 
	
Any insite for this novice apreciated?
891.3What He Meant Was ......??AQUA::ROSTCanned ham, that's for meThu Oct 06 1988 14:1737
    Re: .2
    
    1. NO  you CANNOT assume anything with XLR jacks is balanced....just
    ask Dan Eaton. 8^)  8^)  8^)  In some XLR gear the third conductor is
    grounded, which makes things unbalanced, which removes the whole
    advantage of going to XLRs in the first place...balanced lines have
    superior noise immunity. 
    
    2.  Placement of the power amps relative to the speakers has to do with
    power loss.  Running high power amps it is ideal to use very large
    gauge speaker cables and to keep them short.  The resistance loss of a
    speaker cable is roughly inversely proportional to the conductor
    thickness (i.e. gauge) and proportional to the length. 
    
    If you use a cable that is twice as thick and run it only half as
    far, the power lost *in the cable* will be cut by a factor of 4.
    Long runs of narrow gauge cable can generate a lot of heat if high
    power is applied to them....heat is the biggest thing leading to
    cable breakdown (other than physical abuse).  Plus it saps watts
    that could be going to your speakers.
    
    If you therefore decide to place the power amps close to the speakers
    and away from the mixer, you need balanced low impedance lines between
    mixer and amp unless the separation is under 20 feet (in which case
    high impedance will work, but low impedance is still preferable).

    As far as the EQ needing XLR outs, look at it this way...whatever
    unit is directly connected to the power amps must have XLR outs.
    So if the signal goes from board to EQ to amps, the EQ needs XLR
    outs but the board doesn't.  
     
    If the device doesn't have XLR outs you can use transformers that
    convert 14" high impedance, unbalanced to XLR low impedance, balanced.
    
    
    
891.4Lo/Hi/Bal/Unbal/Line/MicLEDS::ORSIYou live around here often?Thu Oct 06 1988 16:1222
    Re-.3
    >and away from the mixer, you need balanced low impedance lines
    >between mixer and amp unless the separation is under 20 feet
    >(in which case high impedance will work, but low impedance is
    >still preferable.
    
    	You are confusing low level (~100mV) lo and hi imp
    	signals, like a mic or guitar output, with line level (~1V) 
        lo imp balanced and hi imp unbalanced signals, like a mixer, 
    	eq, delay, compressor, etc. output. Line levels lo or hi can
    	be driven down long lines, like the returns on a snake back
    	to the power amps from a mixer. But like someone said, balanced
    	lines will greatly improve noise immunity. I run my PA system
    	totally unbalanced with no problems. All my patching is done
    	with 1/4" to 1/4" cables.
    
    	Neal
    
    
    Hi impedance mic cords and guitar cords should be kept under 20 ft 
    to prevent hi and lo frequency losses. 
    	
891.5Good info!CSC32::G_HOUSEBack in BlackThu Oct 06 1988 16:275
    Thanks all, I was thinking of the EQ to use with my guitar and/or
    PA, so it sounds like I'd better avoid the ones designed for home
    audio use.
    
    Greg
891.6My bug might be EQVOLKS::RYENRick Ryen 285-6248Thu Oct 06 1988 17:0527
	Yeah, thanks from me also. I'll have to check out
	the actual PA set-up to see, but I think we may have
	things that break some of the rules that you have discussed.

	As I recall, our EQ has only RCA plugs. The setup is owned
	by a keyboard player, so I suspect that he got the EQ
	FOR keyboards, and just started using it on the full PA.
	From what I've seen keyboard stuff seems to
	have lots of RCA plugs, so it probably works fine for a
	keyboard only set-up.

	You wouldn't believe how extensive this PA is, yet it
	still doesn't sound right. There is a fly in the ointment 
	somewhere, and it seems to be AFTER the mixing board somewhere.
	I suspect the EQ or cable-ing.

	Some pro's have run the board a few times, and they seem to
	magically get it tweeked up just fine. Seems like when anyone else
	(including myself) touches it, it goes downhill quick. 
	It never makes a clean transition from one set-up to 
	another without lots of bugs.

	Maybe I'll start a new note on the subject of PA set-ups
	and such. I could use a few tips.

Rick

891.7more thoughtsANT::JACQUESFri Oct 07 1988 11:5754
    
    For anyone interested, Peavey has a nice write-up about
    low impedance vs high impedance, balanced vs unbalanced,
    line level vs mic level, etc. in their pro equipment
    catalogue. It was written by Jack Sondermeyer. Any Peavey
    dealer should have catalogues with this article in them.
    
    I guess I need to correct what I said in .1, Stereo equipment
    does run on 1v line levels (Thanks for the info, Niel). 
    
    I find the home recording equipment is where the differant
    standards all come together, as home recording gear often
    includes 1/4", RCA phono, and even XLR inputs on some models.
    I get around this by using adaptor cables rather than using
    adaptors between 2 cables. You can buy cables from Hoya,
    Peavey, Whirlwind, etc. that feature 1/4" on one end, and
    RCA phono on the other, or any other configuration you need.
    You can also use transformers to go from a balanced line into
    a 1/4" input on a recorder, mixer, etc. when they don't have
    balanced inputs.
    
    I ran into a situation a while back that made me wonder. A guy 
    showed up at a jam and wanted to plug his keyboard into the PA 
    via the 1/4" line out jack on his amp. He didn't have a long enough
    cable, so I tried to use a mic cable with a transformer on the end, 
    no-can-do. The transformer is only meant to work one way with 
    the input going to the primary, and the output taken from the
    secondary. The XLR male/female scheme prevented me from connecting
    things this way, fortunately. I found out that the only way to
    accomplish this sort of thing is with a direct box. I am considering
    getting one or two direct boxes for the next time I encounter this
    problem. I suppose I should get active boxes if I am going to
    get any. Anyone care to suggest a good quality, reasonably priced
    active direct box I should look into? Maybe I should just buy some
    long unbalanced cables for this purpose since 1v line levels can
    travel across unbalanced lines without signal loss problems? What
    is the max length I could run 1v line levels across unbalanced 
    lines without noise problems ?
                                  
    Mark Jacques
    
    
    
    
    Another thing about home stereo equipment to keep in mind
    is that it is not road worthy. It is designed to sit in
    your home entertainment center semi/permanently installed.
    Even if it has rack ears on it, this does not mean that
    it is pro gear. RCA phono jacks are not designed for constant
    plugging and unplugging. You can buy high quality, fairly 
    durable RCA phono cables, but the jacks on the rear panels 
    of stereo equipment can only take so many insertions.
                               
    
891.8more eq info needed !!!ANT::JACQUESMon Oct 10 1988 17:5920
    While we are on the subject of Equalizers, I am considering
    getting an eq for my PA system, as well as one for my guitar
    effects rack.
    
    For the PA, I sometimes run stereo, sometimes mono, but I think
    I would be better off with a stereo unit. Even if I am running
    mono, I could EQ the voices and instruments separately. I have
    looked at EQ's from Peavey, dbx, Rane, and Yamaha. I have narrowed
    the field to either getting a Rane, or a dbx. The dbx model I am
    interested in has a neat feature. It can either be used as a
    stereo 15 band/side eq, or a mono 31 band eq, selectable at the
    flick of a switch. Is anyone familiar with this unit? What do
    you think? Would I be better off witha Rane? The dbx is around
    $300 to $350. How much for a good Rane eq ?
    
    For guitar playing, how is the SRD half-rack eq's. How about the
    Boss mini studio eq. Would either unit work well in an effects
    loop with a distorted signal slamming into them ??
    
    Mark
891.9MARKER::BUCKLEYQuayle? AhahahahahahahahahahahahahahahahahaMon Oct 10 1988 18:2315
    
    Peavey has a nice dual 15 band graphic for a little over $200. It has
    some nice features like low cut filters, and some notch effects.  Its
    nice because the frequency resp. of the unit doesn't change as you
    boost/cut the output level! 
    
    Ibanez has a dual 15 band, but its not as nice.
    
    Don't like the DOD eq's...too noisy!!
    
    The Scholtz stuff is *OK*, not as bad as some stuff.  I'd get the
    scholtz unit over, say the BOSS half rack 10 band graphic.
    
    I like the stereo eq's because you always find use for an eq even
    if application isn't immediately nec.
891.10Another EQ questionCSC32::G_HOUSEDracula SucksTue Nov 01 1988 13:503
    What is the difference between a graphic EQ and a parametric EQ?
        
    Greg
891.11Parametric Vs. GraphicAQUA::ROSTYou've got to stop your pleadingTue Nov 01 1988 14:1157
    
    A graphic EQ is so-called because it usually uses sliders, so that
    you get a "graphic" representation of the EQ adjustment by looking
    at the slider positions.  It is just a multi-band EQ with all interior
    bands being of the "peaking" type....that is, the boost/cut is maximum
    at the marked frequency and drops off as you move away from that
    frequency in either direction.  The highest and lowest bands may
    also be peaking, or they may be "shelving" types, that is, moving
    in one direction away from the center frequency, the boost/cut falls
    off, but in the other direction it remains constant.  In simple
    EQ systems (like your guitar amp, bass and treble are usually shelving
    type and mid usually peaking type.
    
    Shelving:
    
    --------                            ------------
            \                          /
             \----------     ---------/  
    
    Peaking:
    
                        /\            --------------    --------------
                       /  \                         \  /
    ------------------/    \---------                \/
    
    
    A parametric EQ is almost always of the peaking type.  Simple
    versions (sometimes called semi-parametric or quasi-parametric)
    simply allow you to choose the center frequecny where the boost/cut
    will occur.  In true parametric systems, you can also adjust the
    "Q" or slope of the boost/cut.  In other words, you can have the
    EQ act on a very narrow range of frequencies (good for feedback
    control or eliminating "dead spots" on your guitar neck) or act
    on a wider range of frequencies for more broad tone shaping.  Most
    parametrics have fewer bands (maybe 2 or 3) than graphics, which
    may have anywhere from 5 to 31 bands.
    

    Narrow Q:
    
    
    
                      /\
                     /  \
    ----------------/    \------------------
    
    
    
    Wide Q:
    
    
    
                      /------\ 
                     /        \
    ----------------/          \------------------
    
   
891.12EQ frequency pointsFRETZ::HEISERask meThu Apr 30 1992 19:215
    Does anyone have info on the basic cutoff frequencies in relation to
    the guitar?  How do you know what settings to use to achieve a
    particular sound?
    
    Mike
891.13pontification alert...EZ2GET::STEWARTYou're just supposed to sit here?Thu Apr 30 1992 20:2617
    
    Don't have numbers for you on the first question, but I'm reasonably
    sure the fundamentals are with the 100 Hz to 5 kHz.
    
    In response to your second question - you need two precision
    instruments: your ears and your brain.  First, you need to listen
    critically to the sound you're after (if you're trying to emulate and
    existing sound).  Secondly, you need to be able to hear what your EQ is
    actually doing to the sound you're shaping.  This means not only
    shaping the frequency response curve, but being able to distinguish how
    the effects affect the sound, also.  I know this is incredibly
    obvious...
    
    The thing is, EQ is not sufficient to change the voice of an instrument
    beyond some small degree.  No amount of EQ is going to make a strat
    sound like a Les Paul...
    
891.14RAVEN1::JERRYWHITEHey you're pretty good - NOT !Thu May 07 1992 09:2121
    I need some advice on stomp EQ's for guitar.  I'm gonna buy one *real*
    soon .... anybody got any pro's or con's about any of 'em ?  What have
    ya had, what did ya like, what did ya hate, how much was it, have ya
    got one you'd like to sell ?
    
    Here's what I'm gunning for.  I'll be using a Laney combo on a clean
    setting, an Ibanez Tube Screamer (or something similar) for nastier
    stuff, and the EQ to boost clean and dirty voices during leads.  A wah
    will be in the chain on occasion, should "Voodoo Chile" enter the
    picture.
    
    If the EQ gets a *little* dirty when the signal is boosted, that's
    fine.
    
    Talk to me ....   8^)
    
    ps - Hey Greg, can I buy that Wasburn back (complete with the custom
    2EZ graphics on the bottom).
    
    
    Jerry
891.15.02's worthWEDOIT::KELLYJThink for yourselfThu May 07 1992 10:313
    I haven't used a floor EQ for a while, but I did use two in the past: a
    6-band MXR graphics, battery powered, and a 10-band MXR, AC powered. 
    Both worked okay as EQ's, but the 6-band was WAY noisy.
891.16guit - eq - amp is my signal chainDEMING::CLARKaccept STRESS into your lifeThu May 07 1992 11:5216
    I use a DOD 7-band EQ and I think it works fine. You can boost or
    cut by up to 12dB for each channel, and boost or cut the overall 
    gain by 12dB. I paid about 55-60 bucks for it. Using it to boost
    clean and dirty voices during leads is one of the primary uses I
    have for my EQ pedal. Keep the overall volume flat, boost the
    800 hz band about 6dB, the 400 and 1600 hz bands about 4dB, and
    maybe the 200 and 3200 hz bands about 2dB. This will make your
    guitar signal fatter and louder, but not so loud that you totally
    overwhelm your non-eq sound.
    
    The other thing you can do is use the same settings but boost the
    overall volume about 3 dB and keep it on all the time. Your amp
    sees a much stronger, fatter signal coming in and gives you more
    total crunch per unit of music that way.
    
    - Dave
891.17Tube screamer +GE7 = AhhhhhhhhhhhESBTRX::KALINOWSKIThu May 07 1992 12:2317
Jerry......

The best combination I've ever heard was ....


Guitar--->Boss GE7----->Tube Screamer----->Marshall

This worked perfectly for the type of setup you described. I've heard the GE7,
the Ibanez parametric, the MXR and the DOD and the Boss takes the cake for 
floor stompers. (Unless TC or Lexicon makes a stomper I don't know about)

Try the GE7, I guarantee you'll love it in conjunction with the tube screamer
I use one with my Marshall.

Brian

891.18CAVLRY::BUCKyour ghost haunts my soulThu May 07 1992 12:305
    >>Guitar--->Boss GE7----->Tube Screamer----->Marshall
    
    
    Two big votes for this combo!!
    
891.19Thanks guys ... I see the light !RAVEN1::JERRYWHITEHey you're pretty good - NOT !Thu May 07 1992 12:598
    Sounds like a plan.  From the propaganda I've been reading, the GE7
    seems to be a superior unit.  Kinda high though ... $89 from American
    Musical Supply.
    
    Strat ---> Boss GE7 ---> Classic Tube Screamer ---> Laney ProTube Combo
    
    
    Jerry (with the VISA in his hand ... 8^)
891.20Three BIG votes...KDX200::COOPERStep UP to the RACK !Thu May 07 1992 13:357
A little steep perhaps, but you get whatcha pay for...

The GE7 is a nice unit for boostin' the input gain as you 
described.  I bet that Laney screams with a TubeScreamer and
a GE7.

jc (Who was the original owner of that Washburn/2EZ special :)
891.21RAVEN1::JERRYWHITEHey you're pretty good - NOT !Thu May 07 1992 13:467
    Yeah, I remember.  I think that pedal was the first thing I ever sold
    through notes.
    
    I gotta demo a GE7 this weekend for sure.
    
    
    Jerry
891.22I thought I saw one in 2.*FRETZ::HEISERask meThu May 07 1992 13:581
    Wasn't someone in here selling a GE-7?
891.23RAVEN1::JERRYWHITEHey you're pretty good - NOT !Thu May 07 1992 14:003
    If so, would they please stand up !  8^)
    
    Jerry
891.24As a service to our readersSSDEVO::LAMBERTGonna boogie my scruples awayThu May 07 1992 14:163
   See note 2.1923.  "search" is a wonderful tool.  :-)

   -- Sam