Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #20 on: March 05, 2018, 08:40:30 PM »
The Quad Eight 712 graphic and the Sphere 900 graphic are two of my favorite EQ's ever. A 31 band graphic wouldn't be something I'd want for tracking or mixing.


Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #21 on: March 05, 2018, 09:43:38 PM »
I'm kind of surprised there aren't more graphic EQ's around here.  A classic "swinging input" topology only uses a single opamp for all bands. It seems well suited for a DOA since you only need one.

squarewave

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #22 on: March 06, 2018, 12:30:58 AM »
I'm kind of surprised there aren't more graphic EQ's around here.  A classic "swinging input" topology only uses a single opamp for all bands. It seems well suited for a DOA since you only need one.
If the frequencies are close, adjacent bands will interact a little. Usually at least 2 op amps are used, one for odd bands and one for even bands (like the Klark Teknik DN27). But for better separation, more stages may be required (the UREI 527 uses 4 op amps each handling every fourth band).

Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #23 on: March 06, 2018, 01:14:22 AM »
For broad shaping I don’t think a little interaction is a bad thing. The QE712 uses two amp blocks.

abbey road d enfer

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #24 on: March 06, 2018, 02:21:42 AM »
I'm kind of surprised there aren't more graphic EQ's around here. 
For tracking, the issue is that a decent graphic EQ cannot be put in each channel.
Quad-Eight and API used to have GEQ's in their consoles; they were never popular, because they did not have enough bands, the controls were small and fiddly, and, as I wrote earlier, they could not be used for surgical EQ, where parametric reigns.
Now, going outboard, if one wants to have GEQ's with big faders on each channel, there is not enough space in the FX rack!
Admittedly, for "bedroom" tracking, that would be possible.

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A classic "swinging input" topology only uses a single opamp for all bands. It seems well suited for a DOA since you only need one.
This is true only if is made use of real inductor-based resonant tanks; when "gyrators" are used, their noise add significantly, and yes, the noise contribution increases when a band is cut, as much as when it's boosted.
Since real inductors are no more commercially viable, there are only two types of GEQ's commonly available, those that use the swinging input topology with so-called gyrators, and those that use the cascaded Baxendall-derived structure, where there are as many sections as there are bands.
Although these two types have different behaviour regarding noise build-up, it turns out it's hardly a significant factor in practice; users are much more concerned with the sharpness of bands and the feel of faders.
Anyway, GEQ's are steadily losing favour since most digital mixers have some kind of rather efficient parametric EQ built-in; statistically, GEQ's are for old geezers who have not made the transition.
I would think no one is actually losing hairs over designing the best GEQ in the universe...
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #25 on: March 06, 2018, 12:42:49 PM »
For tracking, the issue is that a decent graphic EQ cannot be put in each channel.

The exception to that rule is the Sphere 900. It used paddle activated rotary switches for for each band. I agree that the API graphic is too fiddly. The QE712 used full sized faders. If they were fitted into a console there would only be a couple that were patchable.

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Since real inductors are no more commercially viable, there are only two types of GEQ's commonly available, those that use the swinging input topology with so-called gyrators, and those that use the cascaded Baxendall-derived structure, where there are as many sections as there are bands.

Coils are popular around these parts. I was surprised not to see more DIY projects. I understand it's not commercially viable.

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Anyway, GEQ's are steadily losing favour since most digital mixers have some kind of rather efficient parametric EQ built-in; statistically, GEQ's are for old geezers who have not made the transition.
I would think no one is actually losing hairs over designing the best GEQ in the universe...

I'd say the average DIY'er would find good use from a pair of really nice five to eight band GEQ for general shaping. I agree that a semi parametric is more useful in a console strip. Mostly because you can use concentric knobs for lots of frequency and gain positions. It doesn't make sense to use concentric controls with a graphic so you are limited to half the number of controls.

abbey road d enfer

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #26 on: March 06, 2018, 01:34:34 PM »
The exception to that rule is the Sphere 900. It used paddle activated rotary switches for for each band. 
I was not aware of the Sphere but I remember a similar product, don't remember the brand, that was almost unusable as the contacts got scratchy. These pushwheel switches are not designed to withstand the rigours of a studio; they are more or less "set and forget".

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The QE712 used full sized faders.
I may be wrong but i'm convinced I saw a QE console with cassette-sized graphics; they may have been 3rd-party.


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Coils are popular around these parts. I was surprised not to see more DIY projects.
There have been some threads around here about DIYing inductors. Very often I think people are timid, thinking inductors have some kind of magic that is not accessible to them; I believe most people who make inductors and transformers are guilty of impregnating their business with so much mystique.

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I'd say the average DIY'er would find good use from a pair of really nice five to eight band GEQ for general shaping.
Not for me... Well, except if I had nothing else.

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  I agree that a semi parametric is more useful in a console strip.
Definitely.
But my comment was not limited to studios, it's a serious trend in live sound too. There are many gigs where there is no graphic, often they are not in riders. Some SE's have developed a hate of graphics that I find unjustified. It's bad usage that gives them bad reputation; if they had learnt how to use them, they would at least accept them, maybe love them, but now that learning the trade is posting on GS, what can you expect?  :(
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #27 on: March 06, 2018, 02:12:04 PM »
I was not aware of the Sphere but I remember a similar product, don't remember the brand, that was almost unusable as the contacts got scratchy. These pushwheel switches are not designed to withstand the rigours of a studio; they are more or less "set and forget".

I haven't heard of too many problems with those switches.

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I may be wrong but i'm convinced I saw a QE console with cassette-sized graphics; they may have been 3rd-party.

Not a 712. Maybe there were later models I'm not aware of. I'm only interested in the 310 and 312 series.

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There have been some threads around here about DIYing inductors. Very often I think people are timid, thinking inductors have some kind of magic that is not accessible to them; I believe most people who make inductors and transformers are guilty of impregnating their business with so much mystique.

I've been using a pair of QE310's for over 20 years. It's discrete transistor with the inductors i the feedback loop. I use it because I love it. I hardly ever discuss gear with clients. I discuss their project and if they are interested and ask I'll talk about it. But i won't stop the flow of a session to brag about a box.


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But my comment was not limited to studios, it's a serious trend in live sound too. There are many gigs where there is no graphic, often they are not in riders. Some SE's have developed a hate of graphics that I find unjustified. It's bad usage that gives them bad reputation; if they had learnt how to use them, they would at least accept them, maybe love them, but now that learning the trade is posting on GS, what can you expect?  :(

I stopped doing live sound before digital consoles were popular. I always was suspicious of graphic EQ's. The first thing I'd do in a new venue was pop them out to see if the system sounded better that way. They are a crude tool for feedback suppression. I'd much rather have one of these modern digital crossovers with parametric notch filters.

abbey road d enfer

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #28 on: March 06, 2018, 02:45:39 PM »
They are a crude tool for feedback suppression.
Agreed. But there was a time where it was the only tool available.  They're good for room EQ, though, provided the user knows what he does.

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I'd much rather have one of these modern digital crossovers with parametric notch filters.
For monitors, yes. For FOH, they as much pros than cons; one could be drowning in trying to get a perfect ruler-straight response and forget to do the gig!
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

Gold

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #29 on: March 06, 2018, 02:52:46 PM »

 For monitors, yes. For FOH, they as much pros than cons; one could be drowning in trying to get a perfect ruler-straight response and forget to do the gig!

I was talking about feedback suppression. A 31 band graphic rarely has the frequency point you need. Ruler straight frequency response is overrated.


abbey road d enfer

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #30 on: March 06, 2018, 04:54:03 PM »
I was talking about feedback suppression. A 31 band graphic rarely has the frequency point you need.
Yes, but as I said, when a graphic is all you have...

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Ruler straight frequency response is overrated.
Indeed! That's the common mistake that many make, and blame the equipment.
Who's right or wrong is irrelevant. What matters is what's right or wrong.
"The important thing is not to convince, but to give pause for thought." (B. Werber)
Star ground is for electricians.

JohnRoberts

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #31 on: March 06, 2018, 05:55:32 PM »
I was talking about feedback suppression. A 31 band graphic rarely has the frequency point you need. Ruler straight frequency response is overrated.
Any graphic will boost or dip a bunch of frequencies around a nominal center point, so any graphic will work to reduce feedback modes. A  1/3rd oct (31 Band)  will trash less nearby frequencies than 2/3 oct or full octave.

Don't get me started talking about feedback, which as I've already shared is not a studio concern.

JR
John Roberts
http://circularscience.com
Tune it, or don't play it...

helterbelter

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #32 on: March 08, 2018, 04:24:41 PM »
I have had several graphic eq's for toneshaping.  Some worked better than others. Urei 527 (IIRC) Urei, 535 (I liked this one), a cheap unbalanced hifi monacor (- and this one really rocked !), White Instruments 4400)

Nowadays I have only one (dual mono), and it's the best one I ever had : Audient ASP231.  It doens't have the mojo of the Monacor or the Urei 535, but it's very transparent, and it's easy to get the sound right with this one. It also has a tilt control which is very useful.
And this one can be found on the second hand market fairly cheap. At least , here in the netherlands.

sr1200

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #33 on: March 08, 2018, 08:28:19 PM »
Helter,
are you aware of replacement faders for the 535?  A guy by me is selling  a couple of them for a pretty decent price.  Was just looking at them today.  One has a fader that is non functional the rest seem like they may just need a good deoxit bath (not literally).
MEI Studio - Long Island, NY: http://www.meirecords.com

squarewave

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #34 on: March 08, 2018, 09:03:29 PM »
are you aware of replacement faders for the 535?  A guy by me is selling  a couple of them for a pretty decent price.  Was just looking at them today.  One has a fader that is non functional the rest seem like they may just need a good deoxit bath (not literally).
Amazingly I just came across this from random Googleing:

http://www.jjstudioelectronics.com/product_urei_535_control.php

which is just like what I did for the 527a:

http://squarewav.blogspot.com/2015/08/urei-527a-replacement-slide-assembly.html

If the faders on the 535 are anything like the 527a, no amount of deoxit is going to fix it. They used some kind of weird grease that just turned into caked on tar. The best option is to make a new assembly like above. Amazingly our two solutions are basically identical.

sr1200

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #35 on: March 08, 2018, 11:46:47 PM »
wow... me thinks perhaps i should pick these units up.  That would be a pretty cheap fix.  Thanks
MEI Studio - Long Island, NY: http://www.meirecords.com

sr1200

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #36 on: March 09, 2018, 03:31:16 PM »
whered you get the little condoms to go on the ends of the fader stems (or whatever they're called).
MEI Studio - Long Island, NY: http://www.meirecords.com

helterbelter

Re: Hi-Fi Graphic EQ as Tracking EQ? New
« Reply #37 on: March 10, 2018, 07:25:23 AM »
That replacement panel looks like a great idea.

Helter,
are you aware of replacement faders for the 535?  A guy by me is selling  a couple of them for a pretty decent price.  Was just looking at them today.  One has a fader that is non functional the rest seem like they may just need a good deoxit bath (not literally).

I had a spare panel with good sliders from a 527/529/530, can't recall which one precisely. But I never needed to replace any of the sliders on the 535.... They weren't very smooth, but also not so bad that I felt the need to replace them.

Unlike the sliders on the 527's that I had. These were very sticky, and I always was afraid I would break them....

Speaking of the 535's: I once read online that Michael Wagener used these a lot, and he got the sliders replaced by some kind of switches. Haven't seen the actual units though.
« Last Edit: March 10, 2018, 10:20:01 AM by helterbelter »

squarewave

Re: Hi-Fi Graphic EQ as Tracking EQ?
« Reply #38 on: March 10, 2018, 10:00:50 AM »
whered you get the little condoms to go on the ends of the fader stems (or whatever they're called).
Those are actually toggle switch caps NKK AT4003A. Not a proper part for those faders but they worked pretty well.  I would have used the plastic shaft with LED style that that 535 assembly used but the 527A needs 2K pots so my options were limited.