PEQ question & how it relates (converts) to the Dx38

[Coytee]

I've got the EV Dx38 active.

I've got a pair of Danley DTS 10's on their way to me. I've been told that Danley has suggested the following PEQ's to get them to behave.

PEQ minus 8.4dB @ 55Hz, Q=8.9 BW=0.162 BFD=9.7
PEQ minus 4.6dB, @ 29Hz, Q=5 BW=0.2881 BFD=17.3
PEQ minus 7.5dB @ 84Hz, Q=2.8 BW=0.5125 BFD=30.8
PEQ minus 14.4dB @ 154Hz, Q=1.1 BW=1.2701 BFD=76.2

My Dx doesn't have "BW" or "BFD" (at least I don't think it does)

What are they and how would they translate into the Dx?

Second question: Would these PEQ's be better off put on the input side of the Dx (leaving the outputs flat) or, leave the inputs flat and put them on the outputs?

[Coytee]

I just gotta say... it's been SO long since I've fooled with the RACE program to adjust the Dx, I've forgotten how to adjust the silly thing!

Much easier to use the front panel.

[PrestonTom]

The Q, Center frequency and gain adequately set filter. Do not worry about the other two.

[Chris A]

Second question: Would these PEQ's be better off put on the input side of the Dx (leaving the outputs flat) or, leave the inputs flat and put them on the outputs?

I'd put them on the output side but I'd also ignore the PEQs in the above list that are higher than your crossover frequency (nominally 40 Hz) first, i.e., the three PEQs centered at 55, 84 and 154 Hz. That leaves you with but one PEQ: 29 Hz.

I also have found that significant room EQ is needed, so that last remaining (negative) PEQ should probably be seen as a guide only since the room response and where you put your subs will have a much larger effect at your listening position than the half-space performance of the DTS-10s measured outside in a field. [8-|]

Chris

[Edgar]

ISP-100 Manual, page 8-33. I have no idea what "BFD" is, at least not in this context.

[Don Richard]

BFD = Behringer Feedback Destroyer. It uses parametric filters that can be manually tuned. Up to 40 of them, IIRC.

[Coytee]

I'd also ignore the PEQs in the above list that are higher than your crossover frequency (nominally 40 Hz) first, i.e., the three PEQs centered at 55, 84 and 154 Hz. That leaves you with but one PEQ: 29 Hz.

I never even thought of that situation. Good thing the recipe didn't have 35 PEQ's as I would have stuffed hi freq shelves, filters and anything else under the sun into the program!

[mark1101]

I believe BW (Band width) and Q are the same thing. BW is in octaves. My Ashly is setup this way. You can find converters on the internet to convert between Q and BW.

[bobdog]

I run 2 DTS10s. You really need to measure. My PEQ settings for a flat response ended up being quite different than the Danley suggestions. Be sure to incorporate the hipass filter as suggested however.

[Coytee]

Be sure to incorporate the hipass filter as suggested however.

To display my ignorance... would I use a hipass or low?

I would have thought I'd use a low pass so everything under say, 40hz passes through to the Danley and everything above 40hz gets truncated?

Am I backward?

[dtel]

I've got a pair of Danley DTS 10's on their way to me.

[]

You can't just slip that in like nothings going on !

Congratulations, your neighbors are going to love you, not so much.

[Greg Oshiro]

Second question: Would these PEQ's be better off put on the input side of the Dx (leaving the outputs flat) or, leave the inputs flat and put them on the outputs?

I'd put them on the output side but I'd also ignore the PEQs in the above list that are higher than your crossover frequency (nominally 40 Hz)...

Chris

I have to respectfully disagree with Chris on "ignoring the PEQs" . Peaks above (in this case) the crossover frequency if sufficient in magnitude can cause less-than-smooth response above the crossover frequency when the sub combines with the next range up in frequency. Assuming the Danley settings provide flat anechoic response, the subwoofer crossover low-pass filter you program in the DX-38 should behave well using the Danley-recommended EQ. OTOH, I have not measured the Danley, so Chris' experience could well trump my opinion.

...I also have found that significant room EQ is needed, so that last remaining (negative) PEQ should probably be seen as a guide only since the room response and where you put your subs will have a much larger effect at your listening position than the half-space performance of the DTS-10s measured outside in a field.

Chris

I think Chris is right-on on this one. Any speaker radiating sound with wavelengths comparable to room dimensions will require room-specific EQ.

I like to start with something known flat in an anechoic measurement and use input EQ to adjust for room effects, program differences and "taste".

[dtel]

I would have thought I'd use a low pass so everything under say, 40hz passes through to the Danley and everything above 40hz gets truncated?

That's what i would have thought ?

[Edgar]

Much like vented boxes, tapped horns "unload" below their cutoff frequency, resulting in extremely large excursions that can damage the driver, without any significant acoustic output. So a highpass filter is used to prevent any extremely low frequency signals from even reaching the driver. In the Danley it might cut off at 12-15 Hz or thereabouts.

[dtel]

OK, now I remember hearing that.

I only have a choice of full or low pass on the plate amp, always left it on low pass, guess I'm just taking a chance. [:$]

[Chris A]

I have to respectfully disagree with Chris on "ignoring the PEQs" . Peaks above (in this case) the crossover frequency if sufficient in magnitude can cause less-than-smooth response above the crossover frequency when the sub combines with the next range up in frequency. Assuming the Danley settings provide flat anechoic response, the subwoofer crossover low-pass filter you program in the DX-38 should behave well using the Danley-recommended EQ.

I suggested this course of action to simplify the initial setup operations,not as a replacement for eventually instrumenting the room, which I believe is required to EQ below the room's Schroeder frequency. But if no instrumentation is going to occur, then I'd eventually put those PEQs back in the lineup as an approximation.

What I learned with the TH-SPUDs was that the half-space response and the in-room corner-loaded response differed by over 12 dB in peaks. I see why so many manufacturers just tell their customers to avoid corner-loading their speakers - because it typically requires some sort of measurement/EQ process. I know that my room took a day's worth of effort to get well calibrated. The results however have paid off.

[DrWho]

I have to respectfully disagree with Chris on "ignoring the PEQs" . Peaks above (in this case) the crossover frequency if sufficient in magnitude can cause less-than-smooth response above the crossover frequency when the sub combines with the next range up in frequency. Assuming the Danley settings provide flat anechoic response, the subwoofer crossover low-pass filter you program in the DX-38 should behave well using the Danley-recommended EQ. OTOH, I have not measured the Danley, so Chris' experience could well trump my opinion.

Ditto that...the DTS-10 is fairly unweildy above 50Hz. I left filters for all that stuff in at Kovat's place when dialing in his DTS-10. Of course we did all of that in-room and didn't even bother with the recommended settings.

A high pass filter is also a good recommendation since its harder to hear when you're over-driving a tapped horn.