Need help with DSP EQ for OB

[atharva]

I need help with EQ and crossover settings for a OB I’m playing with. I'm using REW, UMIK-1 and MiniDSP 2x4HD and my total experience with all this is just about 3-4 days. I’ve done a bit of reading but the stuff that stood out most was - a couple of videos (links below) and this thread https://www.avsforum.com/threads/si...ow-to-interpret-graphs.1449924/#post-22789786. Also AustinJerry’s setting up REW guide.

There is a lot of material I should read and I will in due course. Admittedly I’m a bit impatient and am hoping to start with something basic and hear some improvements.

The setup is a 1xPRV 10FR300 full range and 2x PRV 15W1000V2 woofers in parallel on each side. Running REW on MacBook Pro. In the MIDI setup MiniDSP is set to 2 channel 16 bit 48 KHz. In REW I've set output to MiniDSP and input to the UMIK-1 with calibration.

To start I'd like to confirm I'm measuring correctly.

1. On the Mac, should the MIDI setup be set for 2-channel 16 bit or 2-channel 24 bit 48Khz?

2. I'm taking measurements with the mic at listening position with mic facing straight ahead (i.e not towards the speakers)

3. It is recommended that I take measurements 60dB above the noise floor. Is it too bad to do it at say 85dB? I understand that more of the noise floor we can ignore, the better.

4. Somewhere it says I should do a 10-20Khz sweep even for a subwoofer? But the specs of the PRV 15W1000v2 say 40-4KHz and I don’t want to damage the sub.

5. I assume I have to take 4 measurements (full range and woofers on left and right) individually and EQ each individually. Finally I take one overall measurement and see how it looks.

I’ve attached a response of the left and right full range at 85dB and I used 1/6 smoothing. Does it look right as in expected? Is it fine? Do you need more information? Should I EQ? If yes, what settings would you suggest?

Videos links..

 

[abdo123]

Use the UMIK-1 as an omnidirectional microphone (point it to the ceiling, and place it at the listening position, use 90deg calibration file). You can experiment with other methods but this is a good starting point.

I'm not sure about the noise floor, but basically do the equalization at the level you would be listening at (maybe 5 dB higher) because that's the level the speakers will be on anyway.

For the subwoofer, measure the range that the subwoofers will be playing based on the rest of your setup and crossover configuration.

I would do the EQ individually for each speaker (200Hz to 20,000Hz), but not each subwoofer (20Hz to 200Hz). because at lower frequencies the two subwoofers might create standing waves by interacting with each other, and they also complement each other. (If you need me to elaborate more on this let me know)

Basically after you did your DSP, make sure that each speaker is reaching your target, and that together they achieve your target as well. Unless you listen to lots of mono music and both speakers recieve the same input.

 

[abdo123]

If you're using Harman's curve, then you might find the measurements from my room a reference to an 'okay' frequency response.

Right now your curve looks more like a hill (or a normal distribution curve) with the peak at 800-1000Hz

 

[atharva]

@abdo123, I thought one of the videos said that you point it towards the ceiling for home theatre application. Do I do it even for stereo? The noise floor when I measured was about 50dB.

Did you mean 20-20KHz for full range or 200-20KHz? The 2 woofers on each side are connected in parallel so I measure them together. What target/filter etc would you suggest to get a curve like yours?

BTW, I can share my REW files if that will help.

 

[abdo123]

BTW, I can share my REW files if that will help.

If they're well annotated, and you tell me what the end device/software will be then i can have a look.

please do new measurements (left, right and both) with the UMIK-1 pointing to the ceiling while it's placed at the listening position.

Follow the preferences below (and put the 90deg calibration file) and use the generator and SPL meter to calibrate the volume to 75 or 85 dB before measuring.

 

[atharva]

Thanks. Will do.

BTW, does it matter if I've chosen 2-ch 16 bit 48KHz or 2-Ch 24 bit 44.1KHz in the MIDI Setup on the Mac?

 

[atharva]

The REW file (zipped) is here https://drive.google.com/file/d/1EKuM-TXM_1OwC2-fEcV1ath4HgiPPuAn/view?usp=sharing

The Left and Right FR have been smoothed using 1/6. The woofers have not been as per a suggestion.

Thanks.

 

[abdo123]

The REW file (zipped) is here https://drive.google.com/file/d/1EKuM-TXM_1OwC2-fEcV1ath4HgiPPuAn/view?usp=sharing

The Left and Right FR have been smoothed using 1/6. The woofers have not been as per a suggestion.

Thanks.

Can you measure the woofers and the full range drivers at the same time? Right now it's difficult to know how loud the bass will be when both of them are running.

Can you provide me more details about your overall gear and setup?

 

[atharva]

Ok. But please confirm i can feed 20-20khz through the woofers.

The system is a PAP trio type DIY with the full range in the middle and the woofers on top and bottom. Width of the baffles is 22inches and total height is 52 inches.