View Full Version : EQ's

07-31-2006, 12:30 PM
Ok so I'm off onto another chapter on the stereo setup. I have been looking at some EQ's and am confused. A local shop has told me that he has he has Ureie 539 and a pair of Yamaha's 31 graphs, but he wants $800.00 Canadian for them. I can purchase a pair of White 4400's for significantly less. Any thoughts on EQ's for a three way setup.

07-31-2006, 02:02 PM
I have both a stereo and monaural Yamaha 31-band eq that I used for L/C/R. I no longer use them because my my Yamaha RX-Z9 has them built in (with self eqing).

I'd let you have than for a lot less than that (say $350 US for the pair) if Canadian shipping/customs isn't a big hassle.

scott fitlin
07-31-2006, 02:46 PM
You can get Urei 539,s on eBay for far less than $800/pr! You are aware that the urei 539,s are cut only, with 20db of make up gain? This means you cannot boost any of the frequencies, only cut them, and then use the make up gain to restore the level from EQing losses.

The Urei 539,s were good, so are the White 4200A,s, which are the same type of EQ, but they are sort of hard to set without an RTA and a calibrated mic and pink noise.

The White 4400,s are cut/boost, and are very good.

If you are going to get the Urei EQ,s you want the ones with the black metal fader shafts, this was the later version. The earlier version with the white plastic faders were prone to really wearing out, and getting stuck. And many found their way to the junk pile because of this reason. As well as there are no parts available for them anymore.

If you do land a mint pair of White or Urei EQ,s, they do sound good, and if you know how to use them can be very beneficial to getting the best from your system.

08-02-2006, 04:10 AM
Never been a fan of EQ’s
My first thought is what are you trying to EQ? if it’s a PA then its OK
If it’s a HI FI buy/build some speakers with a flat frequency response.

But then maybe it’s a bad room that we are trying to sort out.
So if it’s the room you would be better looking at a Parametric EQ.
Typically rooms nodes have very narrow bandwidth and the filter on multi band EQ’s are just too wide and you end up with a “notch” that is wide with a “peak” in the middle instead.

I am currently fiddling with a Varicurve by BSS which uses digital control of parametric EQ.
The filter bandwidth works down to 0.1 octave and is quite useful for removing room nodes.
But you need test gear that has enough resolution to measure what can be very narrow nodes otherwise you don’t have a clue what is happening.
Anyway I was trying to tame a rather problematic room with some good results.
Good for taming subwoofers to.
The BSS has auto EQ and all that stuff but when you start measuring this stuff you find that

Moving the mic has a major impact
Moving the subs mall distances can dramatically affect which room nodes are excited.
So its not as simple as it seems

Solution = build a better room.

Just some thoughts on the subject

Mr. Widget
08-02-2006, 10:33 AM
Never been a fan of EQ’s...I agree with your entire post... I hope to someday build that better room... in the meantime I do employ a small amount of EQ and it is certainly for the better. I do have very sophisticated measurement equipment and I certainly use it, but ultimately we hear differently than how a lab mic hears and all of my final adjustments are made entirely by ear... that said without the test gear I have found that the use of EQs to be mostly frustrating and ultimately detrimental to the listening experience.


08-02-2006, 11:57 AM
I agree with all of you. I have a disasterous room with nodes all over the place. It took almost a month to place my subs in a place where they excite minimal nodes. Having said that there are still peaks ect. and I think eq's are the most cost friendly solution. I have access to a rta and calibrated mic and tech to setup and analyze. I just want a low cost solution.

Thanks for the input.

Mr. Widget
08-02-2006, 12:29 PM
If you do buy an equalizer or pair of them I'd highly recommend the Whites or the Ureis if you can find a good pair of them. The very best of the new digital stuff is also very good but it will cost several times what the vintage analog stuff costs. I would stay away from all of the lesser brands of equalizers and especially the Audio Control and other domestic Hi-Fi types of EQs... they will introduce more garbage than the "fix" they offer.


08-02-2006, 01:29 PM
This raises an interesting issue.

What do you design an acoustic room to do?

I was designing a new acoustically controlled room and you really start to wonder what you are trying to do.
Obviously we want reduced room nodes which we can control by room size but only to a limited extent if we want a practicable liveable room.
It also means acoustically floppy walls so no sound proofing.

Do we meet the Dolby specification for room reverberation? Great for watching movies but perhaps not so great for stereo and living in.
It gives us a narrow sweet spot for stereo but the centre channel on surround holds this together and it’s a bit like living in a Anaerobic chamber.
I compromised here by having all the acoustic absorbers at the screen end and none at the other so this in itself makes a “strange” room for living in as we have a dead end and normal end.
One also ends up with a substantial amount of 6mm hardboard wall lining to control the low frequency reverberation.
Suffer the poor neighbours when the 2242,s kick in.
So I had to design the house as 2 separate sections with a acoustic “break”, the bedroom wing will have substantial sound proofing but the listening/living room has none.

Has anyone built an acoustic room and have any thoughts on this? How did you get on? What specification did you design to.

Mr. Widget
08-02-2006, 02:09 PM
I have heard many purpose built listening rooms and they can be quite aesthetically pleasing and quite an improvement over your standard domestic room in a house. Ideally you "float" the room for sound isolation.

As for achieving different reverberation times (RT60) for HT and stereo, I don't think it is necessary, but one easy solution is to use the same type of tuning found in many studios where you have a wood paneled wall that is essentially a series of large louvers... as you open them you expose a chamber filled with Sonex... for higher reverberation numbers you close the panels... to lower it you open them up a bit.


08-02-2006, 02:10 PM
See Toole's latest paper in the June, 2006 AES Journal....

08-02-2006, 03:53 PM
It gives us a narrow sweet spot for stereo but the centre channel on surround holds this together and it’s a bit like living in a Anaerobic chamber.

Kind of hard to breathe without oxygen isn't it?