Parametric / graphic equalizer recommendations

I have decided my system is too bright. Room treatment did not solve the problem so I am looking at equalizers:

dual graphic eq

(car) parametric eq

They have <.01% THD and 95 dB S/N ratio so don't see them hurting signal too much - I hope.

* Are these good brands?
* Do I need dual eq (one for each speaker)or is mono (average of both speakers)okay?
* Is 31 band necessary. Would 10 band be enough?
* Any place I can get an audio parametric eq. and is this better than graphic eq.?

Thanks for any help.
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.
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.
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,

I need more info to really answer your question. First, what is your system? Second, what do you mean by bright? Are you talking about an emphasis in the 5-8khz range, or do you mean excessive high frequency (>10khz) content? As a rule it's always better to address the root cause of tonal imbalances. My experience is that parametrics are something of a band-aid and of limited effectiveness. Graphic EQs are even less effective.
Well, I'm so impressed by the thoughtful responses I'll say more than I want.
1) Spent a week with our local symphony orchestra and going back to my system, made me realize how bright, even tizzy on a bad CD it can be. At one point I listened to the orchestra with a Yamaha MS-100 monitor up to my left ear and orchestra in my right ear. I could instantly go from the monitor to real music and compare the two. The active monitor was bright even with treble turned way down. It was like shining a spotlight on the high freq.
2) I had a high quality mini system for 18 years. When the recorder stopped working on one speaker, and since I could afford it, stepped up to Nautilus 804 / Musical Fidelity. My room is 13' x 15'. No carpeting, hard walls, and windows on one side with a thin drape. Got the system in Oct. 2001. You can't imagine the amount of stress this whole stereo stuff has been as this was a huge sum of money for me and not even sure why I did all this. I do not part with my money easily. I'd sell it all right now except for the thousands of dollars I would loose. This is because now this whole mess has given me recruitment with associated permanent hearing damage. There are times when in only 10 minutes at 65 dB (conversational level) my ear is burning and in pain. Mild pain which goes on for days. People talk in my room louder but after 10 minutes the stereo is killing my ears. Understand that I never listen above 80 dB and usually around 70 dB so I have not been some smart ass who did this to himself.
I did cover all the walls and floors with carpet and blankets and this cut the reverb but it took something on every wall to help. But this is not enough in my case.
I refuse to turn my living room into an anechoic chamber and I'm not looking at different speakers because of some preference issue. The high frequencies need to be attenuated in a precise and adjustable way. If someone wants to suggest interconnects, I'd want to see measured high frequency attenuation, not just what they hear.
I agree that the reverb has to be addressed, maybe with a carpet. But need to stress: This Is NOT Enough. So if I cannot roll off the highs my whole stereo will go and in a way I'll be glad. I used the CD input on my boom box today, turned down the treble, and listened to music for the first time in almost a month. But even with this, now my ear is paying the price.
Any suggestion would be welcome.
I wonder:
- Why won't a parametric eq. work on high freq's?
- What is exactly bad about graphic eq?
How precious. Right down to the use of "loose." I see I apparently missed where you said room treatment didn't work, but no one responding above intended any offense. Sometimes we're distracted, or sleepy.

Back to your questions. Either, or any, kind of equalizer should help immensely, though I have to add, there is a difference between brightness and harshness. Maybe you should just get a nice receiver or an integrated amp with a treble control that you can turn down.
Whew! Have you been to an ear doctor? (I'm serious.) It seems very unlikely to me that your stereo caused this problem, but if I were you I'd certainly want to find out what did, and what I could do about it.

Your concern is not with "good" sound in the home, but with sound that is personally tolerable to you. If a boombox with the treble turned down can give you pain, an EQ may not help you much with your system. You need to get some auditory testing done. No one wants you to "turn your room into an anechoic chamber", and besides it seems as if you have already gone a long way towards that end. Attenuating the treble may do something, but it won't make your CD's sound like a live orchestra - the differences you heard have as much to do with the effects of mic'ing as they do with your system's balance or the CD medium.

To address your specific questions from above:

1) A parametric EQ will work fine on high frequencies. I think you may be misunderstanding what Rives is getting at with his description of his company's device. It sounds like a brilliant bit of applied engineering to me, but in any case not what you are after here. It is designed to deal with bass frequency room modes specifically.

2) Nothing is "bad" about graphic EQ for your application. In fact, a graphic model might well be the easiest thing to try out in order to satisfy your curiousity.

You are obviously not primarily concerned with "audiophile-approved" solutions, and besides it's not at all clear that there will even be a satisfactory solution to your dilemma. It would be easy to say, with the benefit of hindsight, that a B&W/Musical Fidelity system probably wasn't the best choice for your particular set of ears in your small room, but that's no guarantee you'd feel very much differently had you bought something like a tube electronics/electrostatic speaker system or a SET/small monitor system instead, or even purged your CD's and went all-analog. The devices you are looking at are relatively cheap, so buy one and do some experimenting if you like, but by all means get yourself to a specialist who might be able to help you with your fundamental auditory issue. Best of luck to you!
Cdc: You should see an audiologist or ENT. I am not a physician, but it does sound like you have tenitus (I'm sure I spelled that incorrectely). It is painful and is generally triggered by high frequencies. Speech is midband and does not cause the problem. If you listened to a live jazz band--or just a few cymbol crashes you would probably have the pain. It's frequently caused by some damage to the ear. It can be from being exposed to high SPL for long periods of time (doesn't sound like this is the case for you). But can happen from other things. Divers get it from the changing pressure on their ear drums when diving. I had a friend get it from an air bag going off in a car crash.
I strongly agree with the above comments about seeking medical help.

If all anyone wants to do is in/decrease high frequencies then a low pass filter is more effective than a parametric EQ circuit. Go to the following website and look at the parametric and shelving curves at the bottom of the file and you'll see the difference. The site is a paper presented by George Massenburg outlining the engineering behind parametric EQs. A graphic EQ can be considered as a special case (fixed frequency and sans Q control)of a parametric curve. Traditional treble controls are an example of a low pass filter. As a practical matter nearly all commercially available parametric EQ devices also offer separate low and high pass filters.

CDC, as a quick fix have you ever tried disconnecting your tweeter?
Thanks for the link Onhwy61. I was saying in general about turning my room into an anechoic chamber, not directed at anyone's helpful advise here. Because I have already looked into acoustic foam which absorbs specific frequencies and decided against this type of room treatment.
Fortunately, I had an audiometry done a year ago and I can compared with the one done a couple of weeks ago. Both show hearing loss in the same ear at 8kHz. So the Dr. said it looks like the ear was already damaged due to some "structural problem". I'll see what the otologist says.
I agree Zaiksman that maybe a different speaker would help. For example, I heard Vienna Mozarts this week and highs may be okay but the loose bass was annoying and I would not be happy with it. But like you said, who really knows if any speaker could really solve this problem.
Paulwp, interesting point about brightness and harshness. I compared Swan ?? vs. B&W 602 s2 with Teac receiver. The B&W sounded brighter. But While the Swans were more laid back there was more distortion. At least IMHO. So which was really better? But a distorted CD coming through a bright B&W is not good.
I'll post what I learn.
You were serious about your hearing? Doubly sorry. Brightness, which will irritate and make it difficult to listen to music, occurs in the upper midrange, from below 1 khz to maybe 2 khz (I am inclined to say even lower). Perceived brightness relates more to these higher pitched fundamentals (like the shriek of a 12 year old girl) than to the upper frequency harmonics. Too much energy from 2 to 5 khz is forwardness and hardness, but it can seem bright too. Too much from 5 to 8 khz gives sizzling sibilance and harshness. Too much 8 to 12 khz will be harsh sometimes. Too much above 12 khz, you probably won't even notice. I havent seen measurements of your speakers, but others by the same maker have a tendency to go a little overboard in the 5-10khz after a dip in the 2-5khz presence region.