Parametric / graphic equalizer recommendations

Are any of these any good?
eby parametric eq

Cdc, I am actually a proponent of audiophiles not being afraid to get aquainted with equalizers, but I don't recommend employing one as a permanent system fixture to try and tailor overall response. (There may be an exception to this in the digital response correction components made by companies like TACT and Z-Systems, but while I don't have experience with these, they are intended to perform a somewhat different job than what you describe, go about performing that job in a much different fashion, and of course cost a whole lot more.) In my experience, keeping conventional analog EQ engaged at all times will cause more problems than it might seem to solve at first blush. I would strongly suggest attempting to correct your system's overall balance at a more fundamental level.

However, don't let that discourage you from getting an inexpensive unit to play around with and test my contention. To answer some of your questions, yes, you will want a stereo unit. One of the things you can find out about messing around with a stereo EQ is just how differently two speakers in two different locations respond. Besides that, one of the more legitamate uses for an EQ - helping out seriously flawed software sources for listening or dubbing - can require different settings for each channel of a stereo program. In any case, you'll have a tougher time trying to find a mono unit regardless.

I can't tell you about the brands you link to (or, I'm afraid, any others available today, except to suggest you don't overlook consulting with a pro studio sound retailer), but if you go graphic, you may well find 10 bands to be too few. 31 can be overkill or inconvenient, but I would go with at least 15. I prefer parametric myself for its ultimate flexibility and ease of rapid adjustment, but it can be a little hard to find a true full-parametric unit (that is, with fully variable control over bandwidth, or "Q", as well as over band-center frequency and cut/boost amplitude - many are "quasi-parametric" instead) that has the necessary three or four bands per channel, plus "shelving" switches for the top and bottom bands. Graphic models can also be easier to learn on, due to their visual representation of the adjusted curve. In either case, try to find a unit that has an overall output level control to maintain unity gain at extreme settings or for comparitive purposes (in addition to the de riguer "defeat" switch), along with loop out/in and monitor switch facilities for recording applications.

Have fun if you get one, but I'll mention these words of personal wisdom:
>Don't expect an EQ to completely or accurately fix what you perceive to be wrong with your sound.
>Whatever good it can do, expect to pay a price in other areas, and it may be heavier.
>As my system got better over the years, I found I had less and less call to ever employ either one of my two equalizers for normal listening, even with poor source material. This is not entirely a matter of not needing to correct for non-flat response, either; many of the perceived problems I no longer am troubled by have as much to do with reducing other kinds of distortions as they do with eliminating gross frequency response errors - and I don't even have an acoustically-treated room. It is quite possible that your room-treatment has only served to even more fully reveal some basic system flaws which EQ will not correct for (I say this advisedly, without knowing what your system consists of). My EQ's have been steadily relegated by my improving system to just very ocassional diagnostic or dubbing duty, to the general benefit of the sound, and I no longer miss the tone controls of yore even on the majority of shoddily recorded or mastered material (more true of analog than digital, though). This has proven to me that transparency, cleanliness, and inherent neutrality, from the speakers right back to the AC power and including all the electronics and cables in between, are paramount to forcebly induced "flat" response for the attaining of natural listenability.

Chuck,
Great response from Zaiksman.

I've had a pretty good time with a Rane ME 60 in one of my systems. It's a 30-band per channel graphic equalizer. It offers great flexibility in tone control, but you have to be patient to get it set right. Good luck.

The advice thus far is good, but there are a few areas I would like to caution you on. First, I should tell you that we manufacture a parametric EQ and as such I am biased towards it. However, we designed it with very specific goals in mind and I think it's important to understand those, even if it may not be the eq for you, you can learn from our design strategy. All our company does is small room acoustics. Thus our design not only reflects a superior technical design, it also reflects our philosophy on room acoustics.

The unit is called the PARC for Parametric Adaptive Room Compensation. It is a stereo 3 bands per channel unit that offers variable Q (width of the curve), attenuation, and center frequency. The unit is specifically designed to attenuate bass room modes. Thus it only operates from 18 to 350 Hz (we recommend that it only be used from 200 Hz and below) and it attenuates ONLY. We have it attenuate only because boosting low frequencies can cause other problems such as overdriving an amplifier in a particularly low impedance point of a particular speaker. We also limited the frequency to bass response only. This is because anything above this can be easily treated in the room and we strongly believe in NOT using an equalizer unless you have to. Bass modes are difficult to deal with passively and the PARC is a very practical solution.

The other aspect of the design was sonic quality. We listened to digital correction systems and felt they all thinned the sound. Additionally, we did not want another A/D or D/A conversion that might not be as good as the source from either high resolution digital (SACD DVD-A) or vinyl playback systems. We were looking for the ultimate in transparency and went with an analog design.

Thus I would caution on using an EQ in the higher frequency. You can get rid of brightness in a room and it may be a combination of absorption material, bass re-enforcement, and the speakers. Do you by any chance have a lot of windows in the room? They leak bass badly and will throw off the balance of the system and cause it to sound bright, not unlike a room that does not have enough high frequency absorption.

You can visit our website for more on this unit and go to our listening room where we have tutorial on some basic room acoustic problems.
http://www.rivesaudio.com

Cdc, No answers yet to your specific question, but good responses nonetheless. I don't think you'll find anyone here who has actually used one of these equalizers, so, since they're so inexpensive, why not blaze a trail and let everyone know about your experience?

In response to two of your questions, you need two channels and 1/3 octave (31 band). You need 2 channels because if you are trying to undo room reflection problems (ignoring Rives's very good advice), they won't be the same on each side. You need 31 band because unwanted peaks are sometimes very narrow and you dont want to create a suckout in a nearby frequency.

I agree with Rives, however, that you should only use an equalizer to correct low frequency room problems. I have had brightness problems in one of my rooms, and tried almost everything you can think of, finally deciding that the speakers I had in that room were not suitable for that room. Now, with different speakers, no problem.

I am tempted to ask what speakers you are using. As soon as you answer, however, you'll get 20 recommendations of other speakers, and I know you are pretty familiar with the sonic attributes of a variety of speakers. Others would ask what cables you are using, etc. Let's not go there. It may be that your speakers are just bright. I noticed you commented once that a certain small inexpensive speaker was dull sounding, where I find the same speaker a little rolled off but not dull. Most audiophiles' systems and speakers are too bright for me, the inevitable result of the neverending quest for "detail."

Some things to consider: any glass or other hard reflective surfaces in the room? coffee table between you and the speakers? drapes over windows? how low is the ceiling, and what distance between the speakers, ceiling and you? Speakers tilted back at all? have you tried them in a different room? What happens when you set them up in a nearfield configuration so the sound you hear does not include any reflections?

Good luck,

Paul