Sierra Tower w/RAAL in room response question

[jimlucci]

I have 2.1 setup (music only) with Sierra Towers w/RAAL + Rythmik L12.

Audio chain: PC w/Streaming service -> usb attached Schiit Modi 3+ Dac -> HK3490 Receiver -> Sierra Towers + Rythmik L12

I have been running numerous Room EQ's (w/miniDSP Umik) for baselines and speaker positioning and am getting a pretty steep LF rolloff starting at around 100Hz. It is at about 80 spl at 112Hz and falls to 43 spl at 50Hz. From 100Hz up to 20K it is pretty flat (between 70 spl and 80 spl). Readings that include the subwoofer in the test add some spl to that region (+10db) but the slope downward stays pretty much the same.

I expected to see a flatter response further into the lower frequencies and am wondering if my room has a lot to do with that (pretty big area) and/or that I might be pretty subwoofer deficient. Just wondering what other people have experienced with their in room responses with and without subwoofer.

Rough schematic of my room:
roomdiag3.png

[davef]

I have 2.1 setup (music only) with Sierra Towers w/RAAL + Rythmik L12.

Audio chain: PC w/Streaming service -> usb attached Schiit Modi 3+ Dac -> HK3490 Receiver -> Sierra Towers + Rythmik L12

I have been running numerous Room EQ's (w/miniDSP Umik) for baselines and speaker positioning and am getting a pretty steep LF rolloff starting at around 100Hz. It is at about 80 spl at 112Hz and falls to 43 spl at 50Hz. From 100Hz up to 20K it is pretty flat (between 70 spl and 80 spl). Readings that include the subwoofer in the test add some spl to that region (+10db) but the slope downward stays pretty much the same.

I expected to see a flatter response further into the lower frequencies and am wondering if my room has a lot to do with that (pretty big area) and/or that I might be pretty subwoofer deficient. Just wondering what other people have experienced with their in room responses with and without subwoofer.

Rough schematic of my room:
roomdiag3.png

Have you confirmed that your subwoofers are actually turning on using the REQ sweep? Run the sweep and put your hand on the woofers to make sure there is output. Rythmik subs have an auto-turn on feature that typically takes a few seconds to engage, which is longer than the REQ sweep time.

This is the first step to take for troubleshooting.

[jimlucci]

Yeah, I ran into that once or twice when moving the sub around, but got that procedure down. I made sure the sub is definitely on. To me the music sounds pretty good. Low freq. tracks like Hotel California Live/MTV 1994 kick drum sounds tight with good thump, mids and upper freq have great clarity, great detail. I wanted to use REW as an objective way to find the best speaker orientation for the room/space I have (it is rather large and irregular shaped due to adjoining room). I do zero HT with this setup, but also wondered how much of a difference a bigger sub (or additional one) would make given what I see in the REW output and also what others have found doing measurements in their rooms. I have included REW data below for my two different room orientation options (south and east). They seem similar in values, but I am a little new at interpreting results from REW. Any thoughts on my setup would be most welcomed!!

spl of both south and east main speaker positions:

(NOTE: THESE READINGS WERE TAKEN WHILE THERE WAS A PROBLEM WITH MY UMIK1. LEFT THEM HERE FOR THREAD CONTEXT ONLY)

spl-east-south.png

waterfalls of each:

east:

(NOTE: THESE READINGS WERE TAKEN WHILE THERE WAS A PROBLEM WITH MY UMIK1. LEFT THEM HERE FOR THREAD CONTEXT ONLY)

east-waterfall.png

south:

(NOTE: THESE READINGS WERE TAKEN WHILE THERE WAS A PROBLEM WITH MY UMIK1. LEFT THEM HERE FOR THREAD CONTEXT ONLY)

south-waterfall.jpg

[Mag_Neato]

I'll add my experience to this. I had a similar situation.... a pair of Sierra-2EX's, one 12" Rythmik sealed sub. I was excited to get REW +UMIK-1 and get a picture of how awesome my system was, because, of course, it HAD to be awesome! I was a bit disappointed, to put it mildly. Big dip from 80hz to 50hz, with a spike from 30 to 20hz. Since I had placed my mains where they sounded the best to me, I was left with moving the single sub around to try to fix the issue. No dice. I ended up buying a MiniDSP 2X4HD and a 2nd Rythmik F12. Once I settled on a good placement for the additional sub I began my REW+MiniDSP EQ'ing quest. I 1st got the 2 subs to sum with higher output in the region where I was getting the big dip. Once I had boosted the output there, I was able to use REW to create a EQ slope to cut the boosted peaks down to match the rest of the response. I then added another EQ curve that gave a slightly rising response from 80-30hz of about 10db to account for our poor low freq hearing.

I only EQ the subs from 80hz and lower. Nothing affects the mains. I run a full signal out from the sub out on my Parasound P6, letting the MiniDSP handle the crossover, and a filtered signal to my main amp from the mains output of the P6 crossed at 80hz high pass. I have it sounding pretty darn good right now.

That's my experience, YMMV.

[jimlucci]

Ed,

Thanks for sharing your experience with your setup and process - it is similar to mine. I have been working with REW for about 3 weeks now after reading the help guide and some other online documentation - mostly out of curiosity but also to get data measurements. Using REW has been very helpful in finding the best speaker locations and orientations in my room. It has also been helpful integrating the subwoofer with the towers (phase, crossover, gain). The phase adjustment had measurable REW differences depending on sub location (actual and relative to towers). Crossover and gain settings did as well (dropped the sub x-over to 55-60Hz put the sub gain at 11 oclock). I think I have it setup for my room (difficult space) about as good as I can without formal treatments (not a dedicated listening room) or equalization. Doing the same exercise by ear would have been difficult for me. I think it sounds damn good right now - tonally balanced, very tight, clear and detailed.

When you added your 2nd subwoofer what was the difference for you in sound and measurement?

I have the same dip/void in frequency (midpoint at 70Hz for me) that you and many others experience. I also begin a negative slope in the lower frequencies starting around 90Hz. I am just thinking I could address those 2 issues with the addition of another subwoofer. Then the question is which one? There also appears to be a lot of back-order status on Rythmik subs at the moment.

current REW graphs:

(NOTE: THESE READINGS WERE TAKEN WHILE THERE WAS A PROBLEM WITH MY UMIK1. LEFT THEM HERE FOR THREAD CONTEXT ONLY)

southx60spl.jpg

(NOTE: THESE READINGS WERE TAKEN WHILE THERE WAS A PROBLEM WITH MY UMIK1. LEFT THEM HERE FOR THREAD CONTEXT ONLY)

southx60waterfall.jpg

...Jim

[Mag_Neato]

Jim,

After adding the 2nd sub, with some placement experimentation and adjustments in the MiniDSP, I was able to get the 2 subs to sum together and boost the level in the dip area enough where I could then use REW's EQ prowess to cut the peaks down to a nice, flatter response. I then added a 10db rising curve from 80 to 30hz.

The biggest difference with the 2nd sub is that the bass is more even and there's tons more headroom.

[jimlucci]

Thanks Ed!

How big is your listening room/area? Do you do Home Theater too?

Jim

[Mag_Neato]

My listening room is a bonus room above the garage. It is roughly 11' wide x 27' long with roughly 4' tall knee walls that then angle up on both sides of the 27' length to an 8' flat ceiling. full carpeting. a door at one end and a window centered behind the speakers/equipment. Speakers are roughly 3' out from the front wall and 1-1/2' - 2' in from the side walls. I built corner traps for the front 2 corners and have 4 DIY acoustic panels placed at 1st-2nd reflection points on the side walls. I sit relatively close at about 7'.

I would post a pic of it but I've not had good luck posting pics on this forum and have been patiently waiting for the new updated site to launch, but Dave likes to tease us that it will happen soon!

My HT setup is on the 1st floor in the great room. I do not do any music listening there. It uses Klipsch in-wall/in-ceiling speakers in a 5.2.2(Front L/C/R & Rear L/R, 2 subs, 2 ceiling speakers) Atmos setup powered by a Denon X3300 AVR.

[jimlucci]

That is good size room you have. I am just trying to get a feel for what has lead others to go with multi subwoofer configs (they do a lot of HT or certain music profile or large open listening areas, to mitigate nulls, etc) I have read where others don't feel the need for any subwoofer much less multiples. When I look at my REW sweeps, it seems like I am light in spl from 20 - 90Hz - my listening experience/feel does'nt seem that way though.

[Mag_Neato]

I wonder if those who don't feel the need for a sub have actually taken room measurements with something like REW. If I had not then I'd never have been able to correct the response with the MiniDSP and a 2nd sub. I can certainly understand the K.I.S.S concept and not wanting to screw around with the setup process. Until you've experienced a full, balanced frequency response you don't know what you're missing.