Finding Subwoofer

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ttocs

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Finally, I'll likely order 13As or 15As for the main speakers next year.

The room is horrible for audio. It's about 23' x 35' with the peak of the vaulted ceilings around 13'. It's my living room / dining room / kitchen, with a huge island. Down the right wall (really the "back" wall of the house") is a 16' long pocketed sliding glass door system, and there are no drapes over that. (That's likely the worst part, acoustically, of the room, but the most rewarding *for living* when I open them fully and can enjoy all the fresh air.)

Background out of the way, goals: first, basic 5.2 (5.3?) home theater. Eventually, 2 channel music. (Most of my music listening is at my office, where I have a very satisfying small system.)

At this point, I'm debating if I should set up the BF210s as L/R with the front main speakers, and use the 1100X in an LFE configuration, or use the BF210s in a mono configuration and play with placement to optimize their response. I'm looking at your setup in message 12 and I have some stoopidly basic questions for now:

How are you "splitting" the signal off the front main speakers for the speaker level inputs to their respective subs?​
In your labels "LFE/BM", what does the "BM" stand for?​
Which specific model do you like for your MiniDSPs?​
You are *not* using any of the on-board bass management or EQ of the XMC-2, correct?​
Can't go wrong with either the 13A or 15A! Your room is quite a bit larger than mine, which might help offset all the glass by allowing the setup to move comfortably enough from the glass to help lengthen the delay of reflections. I'm sitting very close to my wall of glass to the right, but the wood blinds help.

RE subwoofer setup, I think I'm getting great results with the "stereo" type setup a'la Rel using the speaker level inputs on the subs, with the stacked subs outboard of the Main Left and Right speakers. It's not where they "should" go, but rather where I want them which is based on how I am using them - as extra woofers for the 13A's in addition to BM and LFE in a mixed connection config. The connection of each speaker to subwoofers is: Amp output to 13A to bottom sub speaker connection to top sub speaker connection, the shortest length of speaker cable possible. This runs the signal through each sub's crossover, which is used to tune the subs to each speaker and the Left subs do not use the same settings as the Right subs. Each sub/speaker combo is tuned to get the best response for its location.

LFE = Low Frequency Effects
BM = Bass Mangement

I like the miniDSP 2x4HD. I started with one, then a second, now a third. Would've been better to have one 10x10HD, plus it's got balanced inputs and outputs which helps with running longer cables. I only use the miniDSP's for BM and LFE.

My Fronts and Center are setup as Large, so there is no BM needed in the processor for these. All the other channels are Small and as such have crossover settings so BM is sent to the subwoofer group. Also, Dirac does the EQ for all channels for HT usage, but I limit Dirac's correction of the 13A's to only below the XO of 300Hz because I haven't yet been totally happy with what correction does with the stat panels. I don't use PEQ in the processor. LFE is sent to the same subwoofer group via separate output from processor using the same miniDSP. Why? Because there has been an issue with the Emotiva processors elevating the bass a few dB and using separate outputs allows for adjusting the LFE and elevated BM individually for perfect results. Emotiva is on the verge of fixing this with the next firmware so I may not need this fix for long, but I'll wait and see.

Also, I'm not using Width channels anymore. The floor speakers I was using affected bass response from the Fronts/Subs so I removed them because two channel music is the primary purpose of my setup. This could change in the future if I were to purchase small stand mounted speakers which would have less effect on the bass from the Fronts.
 

msimanyi

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Thanks ttocs.

From this link, it seems that one can customize the target curve using Dirac:

Dirac Live has automatically generated a response curve, but you can customize that curve by grabbing control nodes, moving them to desired frequencies and then boosting or cutting.​
Does Emotiva's implementation of Dirac Live not allow this or override the customization?

I'm still contemplating your post above, and I'm sure I'll have some questions shortly. I'm just not quite sure how to phrase them right now...

Mike
 

msimanyi

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I thought of at least one question so far.

Given: I'm only trying to integrate two subs into my system, or perhaps three if the 1100x is useful in some manner.
Given: Per the ML manuals for the Balanced Force 210s, these can support both speaker level inputs and LFE inputs, though it's not clear if that's with a concurrent signal. If I'm using line-level inputs to the BF-210s, *and* the LFE signal for home theater playback... do the subs let the smoke out of the wires?

Main question: Do I need a MiniDSP / 10x10? It seems to me that's being used for correction / signal routing, but if I don't need either of those functions, does the product provide any essential function for my (admittedly, much simpler) system configuration?
 

ttocs

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Thanks ttocs.

From this link, it seems that one can customize the target curve using Dirac:

Dirac Live has automatically generated a response curve, but you can customize that curve by grabbing control nodes, moving them to desired frequencies and then boosting or cutting.​
Does Emotiva's implementation of Dirac Live not allow this or override the customization?

I'm still contemplating your post above, and I'm sure I'll have some questions shortly. I'm just not quite sure how to phrase them right now...

Mike
Dirac does allow for customizing the curves for Emotiva processors. I believe it's the same Dirac for all, but, each implementation is a bit different for the exact settings in Volume Calibration for example due to processor differences in input/output specs and which mic is used.

The site you linked to is showing Dirac interface images that are a little different from what I'm used to. Maybe it's one of the mobile interfaces? The main GUI is the same, so I'm just nit picking here.
 

ttocs

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I thought of at least one question so far.

Given: I'm only trying to integrate two subs into my system, or perhaps three if the 1100x is useful in some manner.
Given: Per the ML manuals for the Balanced Force 210s, these can support both speaker level inputs and LFE inputs, though it's not clear if that's with a concurrent signal. If I'm using line-level inputs to the BF-210s, *and* the LFE signal for home theater playback... do the subs let the smoke out of the wires?

Main question: Do I need a MiniDSP / 10x10? It seems to me that's being used for correction / signal routing, but if I don't need either of those functions, does the product provide any essential function for my (admittedly, much simpler) system configuration?
No smoking. You can connect to the Left/Right inputs using XLR, or, RCA, or, Speaker Level Connections, but only one of these connections can be use, - AND - , the LFE input can be use concurrently with ONE of the Left/Right connection methods.
From the BF210 manual, (and the same goes for Dynamo):
"Signal Connection:
  1. 1 Connect the left out/right out from your processor to the Left In/Right In of the subwoofer. Use quality RCA interconnects, XLR interconnects, or speaker level connections. Use either RCA or XLR interconnects, or speaker level connections, but choose only one connection method—do not use multiple methods of connection at the same time for left/right inputs. Speaker level connections are discussed in detail later in this manual.
  2. 2 Connect the LFE output of the processor to the subwoofer’s LFE In. Use quality RCA or XLR interconnects. Please note, the connection method for the LFE In does not need to match Left In/Right In. If you used RCA interconnects or speaker level connections for Left In/Right In it is acceptable to use XLR for the LFE Input. Be flexible, experiment, and listen to determine what sounds best in your unique installation. Do not use mul- tiple methods of connection at the same time for the LFE input."
On my four 1100X and one 800X I am using two inputs on each - a Speaker Level Input and a LFE input. The Speaker Level, RCA, and XLR inputs all run through the sub's low pass filter, but the LFE input does not.

Just to be as clear as possible here, with any of the inputs marked as Left or Right, you can only use one type - RCA, XLR, or Speaker Level. But the one you choose can be used concurrently with either of the LFE inputs - either the RCA LFE Input or the XLR LFE Input. So one Left/Right input pair, and one LFE Input.

About the miniDSP 10x10, I only mention that because it would've been a better, less complicated choice for me. I don't think you need a miniDSP at this point, and even if you decide that you do I'd recommend waiting until you discover a need for one based upon an inadequacy of connections or routing, or, if you need some extra settings or levels (like I do) that the processor is maxxed out of. I mainly use the miniDSP's for routing/distribution, specific levels, delay, and maybe a bit of PEQ.

I would suggest getting your feet wet with just as basic a setup as possible first. If you need or want something that you discover is lacking it'll show up with some trials. If the main purpose of your system is for Home Theater, then start with just using the LFE inputs on the subs and use the subs for BM and LFE. Consider this as "training wheels" for using the new subs, REW, and possibly Dirac. REW for a newbie is a real eye opener, at least it was for me. It gets the brain going in all sorts of directions, so after some experimentation I began focusing on what my goals truly were at the time.
 

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Thanks again ttocs!

REW seems fascinating to me. The graphs showing decay times at the various frequencies seem potentially eye-opening, and your use of walking around with the mic swinging at various points in the room to test response based on your main listening position was equally creative and interesting.

Unless you feel now that it wasn't worth the effort, I'll likely do the same.

I should probably break out the umik mic and the cables I bought, and set up my Macbook to work with it, then I can familiarize myself with using the product.
 

ttocs

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When I did the "mic walk" around my room, it was when I wanted the best location for each of the subs I had at the time, no matter where that might be.

Things changed when I tried some new subs, 1100X, and discovered how much better the new subs were. I decided I wanted to try the Rel method of stacking subs and placing them next to each Front speaker instead of an optimum location. I thought it would be a fun experiment, enlightening, and possibly really great. Turns out it works really well! The idea with this is that I wanted better bass response from the Main Left/Right Expressions.

So you would think the mic walk would've been a waste of time in the end, but it wasn't, because where the right stack of subs is placed is very close to one of the known optimum spots for bass, and knowing this helped when I moved the soundstage from where it was to where it is, which, while still not optimum, is as close as I want it to be considering all factors including room usage.

I do still think it's worthwhile to discover where the good spots are for bass response in a room if only just for having that knowledge handy.
 

ttocs

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FWIW here is my current connection scheme.
211011-Connect-miniDSP1_BM_LFE-miniDSP2_Center_Subs-miniDSP3_LR_Sub.jpg
 

ttocs

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Dirac alone? or, ARC and Dirac?

In several threads in the recent past the question of ARC or No ARC prior to running Dirac, or other correction apps, has come up. After trying Dirac with and without ARC, I came to the conclusion that running ARC and then Dirac was the way to go, but now I have some graphics to show for it.

I'm finally getting around to testing other setups for my subs. So tonight the first one was to see how adjusting ARC settings changes subwoofer output, and then what Dirac does with it.

The REW plots below show one subwoofer in a location that has always been weak in low end bass vs upper bass. The first plot has 3 traces with Blue=No ARC, Red=ARC, and Black=ARC & Dirac. I moved the black trace up so it would be easier to see.
221228-01-Ltop-ARC-noARC-DIRAC.jpg


In the second plot below it's just Red=ARC, and Blue=ARC & Dirac. These are the same traces from above except the Dirac trace is now blue and with no adjustment to the level of the trace.
221228-01a-Ltop-ARC-noARC-DIRAC.jpg


This exercise is simply to show that running correction after running ARC does improve the response.

Also, playing with the adjustments in ARC can make the response do pretty much whatever you'd like, within reason. I chose to make it very flat with very little tilt just for this demonstration. To do this such that no rolloff happens above 120Hz - either from what REW does or what happens with the processor involved, I had to connect the subwoofer to the Center Speaker output of my processor, set the Center channel as Large, and be very careful in how I setup Dirac in the Volume Calibration screen!!!

And, this shows me that ARC does quite a bit of improving on its own, but Dirac helps even further. The reason I want to run ARC first is because of how I want to continue to use my subs connected to the 13A's via speaker level connection. The best possible outcome is when using ARC on each ML speaker and sub.

One more thing. When running ARC I only use 1 microphone position, the MLP. So all five measurements are with just one mic position. I let Dirac do all the heavy math for final correction.

edit: Here is the same measurements from above but with 1/12 Smoothing, which is similar to the smoothing ARC uses. This is a lot easier to decipher. The Dashed Black trace is ARC & Dirac. Both plots above have no smoothing applied.
221228-01-Ltop-ARC-noARC-DIRAC 2.jpg
 
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