What comes first? EQ or scoop?

I think the title says it all. I'm buildin a combo and I need to know in which order I should put the EQ and mid-scoop in. EQ before scoop or scoop before EQ. Your thoughts on this please, thanx.

My thought is that a mid-scoop is EQ.

Not the kinda answer I was hoping for. In my eyes it should not matter, since it's just 2 filters in cascade and (if I forget about load impedance issues) it should give the same result. Are the any other factors technical or aesthetic?

I assume that "scoop" means some circuitry that does tone shaping.

My thoughts are that in case there is no distortion in between the Scoop and the EQ, it does not matter what their order is. ( assumes both input impedances are high and outputs are low)

Suppose the scoop reduces 1 KHz signals by 15 dB and the EQ is set to boost 1 KHz by 5 dB, then the total at 1Khz is -10dB irrespective of what came first.

But if there is some stage that creates distortion in between the two, order makes a big difference.

BTW, do you have any circuit dias for your scoop ? Havent seen any combos with a scoop control. They normally use 3 band EQ so user can set up a scoop if he is interested.

I wanted to achieve the effect that the mid-scoop button(s) on my AVT do. unfortunately I have no idea what the order of scoop, EQ and non-linear amp is.

And I don't know in which order I should put stuff in my machine and yes, I mean a distorted channel.

And as for this question: "BTW, do you have any circuit dias for your scoop ?" I guess dias means ideas . I've tried (by that I mean OrCAD simulation) a tone section of the Omnidrive with the tone pot changed for 2 resistors for kinda balanced bass and treble at around the same level. Second choice was "contour" curicuit from a Marshall VS230R. I got no idea what that machine is, but the curcuit was what i needed. I chose this one. though I had to fiddle with cap values to move the bottom freq of the scoop.

I interested I can provide schems when I get home from work, which is hopefully gonna be soon.

dias = diagrams

OK I get it now, you have improvised a circuit that acts as a scoop button.

It has no distortion and only alters tonality.

You can then stick that in either as :

Non linear -> EQ-> Scoop ->

same as Non Linear-> Scoop-> EQ

or EQ-> Non Linear-> Scoop

Basically I mean that Scoop goes after Non Linear.

Before Non Linear is normally high pass to cut the Bass from getting into the non linear.

Man, thanx a lot...I'll probably go with Non linear -> EQ-> Scoop ->

same as Non Linear-> Scoop-> EQ to change the amount of the newly created harmonix from the nonlinear amp...I really need a cook book whit this kinda stuff

Scoop is most effective as an 'overall' control. Pre1>(either)EQ>pre2>pre3>(or)EQ>Scoop>effectloop>power

Also, the variant usually referred to as 'contour', is a dynamic version of scoop. I think it is much more useful, and is surprisingly easy to build. If you have access to a spectrum analyzer, you can build a contour circuit consisting of a bandpass filter (variable resistor + capacitor to gnd, then capacitor with resistor to gnd)

-D

U're right with the contour. It's not switchable, but "knob-able". The one I took is more complicated than u've explained. Plus, it's really "strong". The pit of the scoop is more than 40dB deep

It all depends on what you want each to do, and what you want to be affected. Scooping the mids out of a signal, then distorting it, gives a different effect that distorting it, then scooping it. That's why high-end mixers have pre- and post- effects sends. I agree with all who say that merely switching the order of the EQ and scoop circuits will make no significant difference.

In general I would say the scoop should be last. Once you get rid of frequencies, you can not bring them back and the other might be boosting, so that should be first.

Depending on your actual desired effect a separate scoop may entail more than just throwing away certain frequencies.

All passive EQ is lossy. Adding in a separate scoop feature is going to result in more signal loss. So you may actually need a scoope and a boost just to maintain the same apparent output level.

A passive EQ is not lossy if used within the preamp itself. Usually the preamp should be built to compensate for that signal loss with a certain control on gain. Any signal processing will be lossy to some degree. There is no perfect filter.

My suggestion is to experiment with a different configurations before sealing the box What matters is if you like the sound!

A passive EQ is not lossy if used within the preamp itself. Usually the preamp should be built to compensate for that signal loss with a certain control on gain. Any signal processing will be lossy to some degree. There is no perfect filter. My suggestion is to experiment with a different configurations before sealing the box What matters is if you like the sound!

By defintion passive EQ is tremendously lossy. Since the only way you can alter tone is by throwing some of it away. The more noticeable the tonal effect, the less signal that is being passed along to the next stage.

If you are saying that a properly constructed pre-amp section should include a recovery gain stage to compenate for losses due to passive EQ I'd agree.

But in the case of SykoJr that also means he will need not just a recovery stage for the normal EQ but also a second one for the switchable mid scoop and that one will need to be linked directly to the scoop switch otherwise it's presence might create too much gain when the scoop was not active. Conversly without that extra recovery the mid scoop will also be a volume drop. when it is active.

But we are not getting rid of frequencies.

We are only attenuating some frequencies.

The overall effect of different linear stages at a particular frequency is the sum of the gains of all the individual stages at that particular frequency. It does not matter what stage comes first. This is true in theory and mostly in practice as well. If the stages are totally linear, the only difference is noise.

Cut a band too much and then boost it a lot = more noise as low signal enters booster

Boost a band and then cut it = less noise but a chance of clipping as too much signal enters attenuator.

Normally you only need about 10-15 dB in the scoop.

If pit is too deep, it will need too high a Q, giving squawky, stuck wah types of sound.

I wouldn't think it would, because it's cutting, not boosting. The effect you describe would certainly result from a band boost circuit that is too narrow.

Heres a link to a guitar equaliser

http://runoffgroove.com/mreq.html

it has sound clips of what +/- 8 dB peaks do to a guitar signal.

40 dB is too radical !!!