More info about Auto EQ needed

Guy Johnson

Hi, I'm glad to have found this Forum . . .

I'd like more information about the Auto EQ settings, and thanks in advance.

In the otherwise excellent manual it says in the Auto EQ Wizard section:

\"You can now select any one of the several different Frequency responses for the Auto EQ.\" It goes on to list the options:

Flat (0) ... OK that's obvious

Response A-D ... What's that mean??



Low, Medium and High precision ... Any figures? Reasons for the choices?


So: What are the reasons for A) the curves, though I can guess, and the differences between the levels of precision, and why it's not on 'high' always.


I have used the Driverack PA twice now for very different jobs (full-range) and very much liked the unit. The anti-feedback and compression features are very useful.

Guy

Gadget

First the easy ones, The Lo, Med, Hi precision settings determine just how precise the Auto EQ is. he Hi setting takes a very long time, and, as you know, the process is not pleasent. The lo setting takes the least time, and is preferable when there are people around. BTW the closer you get with the mic, the shorter the process. The more reflections and modes, the longer as the unit tries to deal with abarant frequencies.
here's what John Lee has to say:


Subject:


John Lee(DBX) explains LOW,MED, HI precision RTA algorithms


07/03/2004

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DRPA RTA Precision (Low / Med / High)
Message date: 12/4/2003
Submitted by: John Lee (dbx)

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Hi Rich,

I implemented the algorithm for the AutoEQ.

To be precise, the difference between low/medium/high is (drum roll please)

Low - all but 4 frequency bands within 1 dB of target.
Med - all but 2 frequency bands within 0.5 dB of target.
Hi - keep adjusting until no further improvement is observed.

In practice, I always found that the Low setting was perfectly adequate. I would store off three different programs that had been tweaked with low medium and high settings, and while SMAART did show a flatter response (or better convergence to the target) my ears could not discriminate between the settings.

If you start with LOW and then AutoEQ at Medium, it does pick up where you left off so you don’t start all over when you pink again.

Conversely, if you force an exit from the current session it uses the “last best� setting.

-John

As for the \"Pre curves\" They are a set of popular emphasis curves used as starting points. They have never given any more indepth description of them, or the reasons for them, or even what each type is best suited for. I can tell you from the posts over the yaers that the \"c\" curve seems to be prefered (other than thosae of us that prefer flat, and then add our own 'colorations) for rock.

Any further explanations will have to be gotten from DBX, and you will have to use the 'tech support' link above.
gadget