Sub to Mains Integeration (REW + minidsp)

I

i_max

Junior Audioholic
Hello,

Since getting my sub back in early Feb. I had been working to normalize the response across the room, with one sub its not easy. The main discrepancies I've had are from my Left and Right seating positions from the MLP. I've got it pretty tight. and this is what it looks like now. Yesterday I matched the LR and the Sub, so they are not creating a null at the cross over.

Initial vs Final.jpg


Sub to Mains Int.jpg


So the top is initial vs final. There was a null at the crossover, initial sub distance in Audessey was 17.1ft, after moving incrementally I got it to 20.1ft where is which I set it to be the final response. The 2nd one also has the L, R & the sub separately. There is no graph smoothing. So it ended up creating a few dips at 120 & 150hz. What else could be done to fix that. Crossover at 80Hz for the mains and higher for the rest of the speakers (90-110hz).

This is the process I've followed so far.
1. Reset Audessey to factory.
2. Using REW created a room curve for the sub, and exported that to minidsp with all other speakers off.
3. Ran Audessey.
4. Then matched the responses as can be seen above.

Is this correct?

something I also noticed was running dynamic EQ in Audessey @ 10db really messed up the whole setup. This is at 0db should I turn that off entirely?

Just while I was writing this post, I noticed the monoprice 15 on sale, and got an order in. That should probably help smooth out the response further.
 
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William Lemmerhirt

William Lemmerhirt

Audioholic Overlord
Looks pretty good to me. Little phase thing around 22hz but it’s narrow and I doubt it’s audible with content. Also, you should try your vertical limits at 45-105. The 60db window is common, and quickly read. It will also show more of the true nature of your FR. What are the subs and mains here?
 
I

i_max

Junior Audioholic
Looks pretty good to me. Little phase thing around 22hz but it’s narrow and I doubt it’s audible with content. Also, you should try your vertical limits at 45-105. The 60db window is common, and quickly read. It will also show more of the true nature of your FR. What are the subs and mains here?
Got it, here it is

45-105 SPL Initial v Final.jpg


L R Sub and Final.jpg


sub monoprice monolith 15” ported and Polk LSiM 707 LR.
 
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I

i_max

Junior Audioholic
I will be receiving the 2nd sub, same as the first one Monolith 15" ported, thanks to the recent sale. I was trying to decide on how to set it up and its placement.

I believe the denon x4300H can independently caliberate both subs, but I also have the 2x4 minidsp HD which can also use the single channel and treat it as a single sub, which would be the preferred approach? I can have two independent inputs from the denon to the minidsp and each have its own output, or use a single line from the denon and output it via minidsp and correct using REW?

The second question was regarding placement, my room is 12' wide x 17' long. I had placed the single sub on the rear right corner which gave me the most even response across the room, however with the dual subs, I can't keep the 2nd one diagonally opposite since my front tower will get much closer to the center of the room. So I was thinking to use put both subs inside of the L & R channel. I had pulled out my LR channel a little outwards and toed them in as below:



and this is the rear of the room with current sub placement.



Please suggest any other changes I could make.
 
I

i_max

Junior Audioholic
Hi all,

Got the 2nd sub over the weekend. Been trying to integrate, it felt like I was not getting a good trim in Audessey even when setting the subs to 3 pm gain, and individual boosting in minidsp. The RCA cables I had been running were old cheap cables, I figured they might have been an issue.
So after replacing them with RCA cables from monoprice, I ran REW, and got decent response (maybe just in my head?), and set a slight room curve. But running Audessey again with 3pm gain on sub and 10db boost in the minidsp i still got “just“ a -5 trim in the denon. So I tried again, this time max gain on sub (5 pm), 9.4 db boost for one sub and 12 on the new sub (this sub needs a 2.6 gain to level match the first sub) in minidsp. This time I endedup with a -11.5 on Audessey.

I changed this to -5.5 and I’m having a great experience in room, tight loud chest thumping bass and all. However I’m just wondering why is it requiring 2 15” subs in a 1600 cubic feet room to be boosted so much to get there? I’ll post the freq response soon.
 
MalVeauX

MalVeauX

Senior Audioholic
Hi,

Since you can measure and all and have a mini-DSP, you can do your subs completely separate if you want hotter bass than what the receiver is deciding. First of course try to place optimally to avoid nulls in the important ranges in all listening positions, averaged if you want. Then level match them at listening position (every sub is a bit different, don't just place them on a default gain setting). Then room response measure them. Fix any nulls first from this point. Then apply whatever curve you wish, if any, and put this into mini-DSP. And add any delay as needed in mini-DSP. Let your AVR calibrate the speakers and leave your subs out. Blend those in manually with your measurements and mini-DSP. Just as an option instead of letting the AVR figure it. That's the point of having the mini-DSP HD anyways.

Very best,
 
I

i_max

Junior Audioholic
Hi,

Since you can measure and all and have a mini-DSP, you can do your subs completely separate if you want hotter bass than what the receiver is deciding. First of course try to place optimally to avoid nulls in the important ranges in all listening positions, averaged if you want. Then level match them at listening position (every sub is a bit different, don't just place them on a default gain setting). Then room response measure them. Fix any nulls first from this point. Then apply whatever curve you wish, if any, and put this into mini-DSP. And add any delay as needed in mini-DSP. Let your AVR calibrate the speakers and leave your subs out. Blend those in manually with your measurements and mini-DSP. Just as an option instead of letting the AVR figure it. That's the point of having the mini-DSP HD anyways.

Very best,
Thank you, I had not thought about this, I’ll give this a try at some point. That said I just want to make sure the subs or minidsp don’t have any issues.
i just tried connecting the subs directly to the Denon, and at 3pm I’m now seeing a -12 trim. I wonder how much signal is reduced when adding the mini dsp. I’ll try this further to see what I need to get ~11ish trim on the receiver, then straight with the minidsp no processing, and then with a curve.
 
I

i_max

Junior Audioholic
Seems like the issue is minidsp. I reset it to factory settings, bypassed the output 2 crossover, and connected subs to output 1 & 2. And started running some pink noise from REW, same thing connected directly to the Denon (with no additional processing), with MV at -41.5 results to ~90db with the mic 4” away. I could see input bars lighting up and then output bars but no sound output, I went up to -26 with no output from the sub.

What am I doing wrong here?
 
William Lemmerhirt

William Lemmerhirt

Audioholic Overlord
Is this a minidsp or minidspHD?
The HD has much higher output voltage and makes integration easier.
Also, is it my eye or are those side surrounds way ahead of the couch?
 
I

i_max

Junior Audioholic
Is this a minidsp or minidspHD?
The HD has much higher output voltage and makes integration easier.
Also, is it my eye or are those side surrounds way ahead of the couch?
It’s a minidspHD. I found the issue, for some reason the master vol in minidsp was set to -19.5, I had thought this was something it was sensing from the AVR, I never changed it, I have moved it to 0, and it fixes the issue.

The speaker is ahead of the couch but it fires towards the rears. I have a door where potentially the best spot was, after some deliberation this seemed like the next best bet.
Current setup with the subs

 
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