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andy13
01-26-2005, 06:45 PM
I listen to mostly 2 channel music. Besides putting acoustic panels and bass traps, can an equalizer ( a 31 band) help in achieving a flatter response? Will the sound quality degrade by having the signal go through another source? Would it be wise to put an equalizer on $3,500 worth of equipment (integrated amp, cd player, speakers)?

risabet
01-26-2005, 07:55 PM
I listen to mostly 2 channel music. Besides putting acoustic panels and bass traps, can an equalizer ( a 31 band) help in achieving a flatter response? Will the sound quality degrade by having the signal go through another source? Would it be wise to put an equalizer on $3,500 worth of equipment (integrated amp, cd player, speakers)?

You'll get a lot of differing opinions on this one so here's mine. I don't like equalizers. They don't change the fundamental problems of nulls, peaks, nodes and standing waves in a room. You can certainly change the sound but you can't improve it, IMHO.

Resident Loser
01-27-2005, 07:49 AM
...after mechanically addressing any loudspeaker/room issues, an EQ can really help...however...permit me to expand, based on my own experience.

Your integrated amp will need "pre-out/power-in" jacks OR a true "tape mon" ckt to get the thing in the signal path and you're good-to-go...almost...for a unit with over say, six bands, using your ears for set-up, IMHO, is a fool's errand. A calibrated pink noise source and measuring tool is really required to come anywhere near proper set-up as it is in your case, with a 1/3 octave unit. I used a Crown test record(with various tone and noise bands) and eventually purchased a RS spl meter which BTW compared favorably with the pro unit I had borrowed from a friend in the trade. I have an older analog metered type, which I prefer over the digital just on GPs...but that's just me.

They(EQs) get a bad rap(for the most part) due to improper use and/or overuse...they are a signal shaper, not a gain device...if correctly set up, when an EQ is switched in and out of the signal path, the tone, NOT level, should change. Using a calibrated noise source and measuring tool, with a 0dB reference point, plotting the set points and applying the inverse to the EQ itself can be somewhat tedious(particularly for those not directly involved). I believe that it was worth the effort however; the marital discord was slight and short lived.

They shouldn't be thought of as "tone controls" per se, leave the ocassional tweak TO your tone controls...once the EQ is properly set-up, fuggedaboudit...it doesn't exist, some(I believe the older Altec units had this feature) have clear plexiglas covers to somewhat preclude the impulse-urge to monkey with them...

Use them judiciously...the need to boost or attenuate more than about 6-8dB can cause problems. The control's Q can begin to affect adjacent bands, in some units more than others...the greater departure from 0dB tends to widen the sliders effective range. Generally speaking(and there can be exceptions)if you can identify a specific frequency band that requires much more than the aforementioned dB limit, you may want to investigate parametrics and/or pro notch filters...but that's where things tend to get really expensive.

I have had excellent results with my system, in my environment, even though my older SAE 2700B is only a half-octave unit. Subtle room treatment(WAF is an important component) coupled with careful measurements, repeated until I pretty much maxed-out(resolution-wise) have given me a detailed and well balanced soundfield with none of the anomolies that most people generally chalk up to "the horror that is equalizers".

Besides, they are fun and informative...before settling down to the serious work, you can "fiddle about" by ear just for grins. EQs can show just how important frequency response is in sound perception...All of the florid, subjective catchphrases and verbiage, many of the attributes bestowed on various products the audiopile cognescenti wholeheartedly embrace and endorse, are demonstrably presented as simply mucking about with frequency response...that is, of couse, if one is willing to have an open mind to listen AND test. Very revealing IMO...to me that aspect alone was worth the price of the unit.

jimHJJ(...have fun and good listening...)

Richard Greene
01-27-2005, 09:54 AM
"I listen to mostly 2 channel music. Besides putting acoustic panels and bass traps, can an equalizer ( a 31 band) help in achieving a flatter response?

RG
For standing wave bass peaks, if you're lucky one control's center frequency might match the center frequency of a bass peak. However most bass peaks are narrower than 1/3 octave and they are not spaced at precise 1/3 octave increments.

A parametric EQ works on bass peaks heard at the listening position. You'll need at least three bands ( and some rooms need five bands) of parametric EQ.
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Will the sound quality degrade by having the signal go through another source?
RG:
You can test for degradation using the EQ bypass control.
Any equalizer will add a little noise and distortion, but the improvement to the frequency response should be far larger, especially the potential improvement to the bass frequency response which often starts at +/-10dB or worse unequalized ... and ends up at +/-5dB or better at the listening position after careful parametric equalization.
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"Would it be wise to put an equalizer on $3,500 worth of equipment (integrated amp, cd player, speakers)?"
RG:
Only if you have measured and heard frequency response errors that reduce your enjoyment of the music.
My experience with equalizers since the 1970's shows that EQ consistently works best for reducing bass peaks under 100Hz. (parametric EQ) and minor adjustments to speaker frequency response (30 band ... and I'm thinking only of cutting output at a few frequencies by no more than 3dB = minor tweaks to your speaker's frequency response ... which can be very audible in the midrange and lower treble frequencies.)
Many people try to do too much with equalizers and make the sound quality worse.