I finally got a mic and used REW to analyze my room. Attached is the freq response for 3 different speakers (Monitor Audio Gold Reference 20, Sonus Faber Electa Amator II, and Sonus Faber Concerto Domus).
They all show similar characteristics - at least the most prominent ones. I did play around with the Amators trying them closer together and more forward in the room, but the major characteristics you see were mostly unchanged.
With this magnitude and number of deviations from a more ideal frequency response curve, am I better off biting the bullet and just doing digital room correction, or can these issues be addressed with room treatments without going crazy and having the room look like Frankenstein’s lab.
Cost is a consideration, but doing it right/better is the most important factor.
If digital room correction is a viable way to address this, what are the best solutions today? My system is largely analog (80’s/90’s Mcintosh preamp/amp, tube phono stage), and streaming isn’t a priority (though I’m not against it).
If the better digital correction solutions come in the form of a streaming HW solution, that’s fine, I’d do that.
Just looking for guidance on the best way to deal with the room, as both serious room treatments and digital EQ room correction are both areas I haven’t delved into before.
Thanks all. If more info is needed, let me know. My room is 11.5’ wide and 15.5’ long with the speakers on the short wall. Backs of speakers are 3-3.5’ off the front wall and they’re at least 2ft from either side wall. Some placement flexibility is there, but not a huge amount.
That's actually not a terrible looking frequency response. I'd focus on some room treatments to try and improve bass response. I'd also (if you can) try and move the listening position to see if you can get that dip in bass to smooth out a little. If you've moved the speakers with no noticable affect, then try and move the chair.
You could also look at filling in the hole in the 40-90hz range with a subwoofer. It would be pretty easy to do and you'd hear the benefits.
Since you're mostly analog, I doubt you'd be satisfied with room correction in the long term, unless you can just add correction to the bass frequencies. You don't describe your system in detail so I don't know if that's possible or not.
I've done a lot of experimentation over the years with room correction and I've always ended up removing it.
Try a couple corner bass traps, add a sub, and I think you'll be 95% of the way there.
Contact Mitch Barnett or read his book on DSP (Amazon.com). I got his book and found out it was too complicated to do myself, so I paid Mitch the $750 for his remote DSP service.
If you have DSP done by him, you should not need other physical treatment options. I had both since I had gotten GIK treatments before I contacted Mitch. I gave away my GIK treatments recently and if I ever need treatments again, I will do it digitally using Mitch's analysis.
This does not help with analog sources like my tuners but is not an issue today in my new rooms.
@rooze My room is a dedicated room for me, so there’s some flexibility in room treatments -within reason because I still don’t want it to look too wacky. But it also doubles as an Atmos HT room and 2-ch audio room. Because of the way my side and ceiling Atmos speakers are placed, it’s hard to move my listening position by too much without getting me out of the ideal spot for Atmos.
I’m using cheap acoustic panels in the corners (not true bass traps) and have some I can use on the side walls, but looking at REW measurements with and without, I’m not sure they’re doing much.
But I can definitely take more REW measurements with the mic in different places to see if that bass dip does smooth out. It can either give me some incentive to try to find a way to move the LP, or resign myself to the fact that it’s not easily fixed without a sub or room correction.
I do have a SVS sub I use for the Atmos system. With some switch boxes (I have two Schiit Sys devices), I can double up the use of that sub for both Atmos and 2-ch (I know it’s not an ideal sub for audio though).
While I’m using all vintage equipment for my 2-ch setup, both preamps I use (Mcintosh C35 and Conrad Johnson PV5) have processor loop options for a hardware DSP solution.
One thing that would seem to work is the miniDSP Flex device which uses Dirac Live. It’s about $750 (I guess $800-825 with tax/shipping) and I believe you can only selectively treat the frequency ranges you want.
On one hand, it’s not a cheap solution, but bass traps from places like GIK can run $400-500 each too, so I could easily spend as much or more than that on acoustic room treatments.
@yyzsantabarbara Where does Mitch's DSP insert into my system? I'm using one of either of two preamps: a late 80's/early 90's Mcintosh C35 or an '80's Conrad Johnson PV5.
Typically, I'll have 2-3 analog inputs into the preamp (CD player, DAC, and tube phono stage into C35 or will use built in phono stage when using PV5). Both have processor loops where something could be inserted into the signal chain to work on all inputs, but for Mitch's solution, would this have to be a computer?
uhm you should never smooth bass region in REW... so use VAR smoothing. Also you need to tackle the modes. Push your speakers closer to the front wall and see how that changes the RTA and the modes in your room. DSP is used in tandem with treatment, but treatment takes precedence @captouch
Room treatment is as much about reverb time (Rt) as frequency variations, particularly in frequencies above 100hz. You don't want sound bouncing around your room. Below 100 is a different story. EQ can help there.
Diffusion and absorption can help minimize frequency variations above 100hz as well as get Rt down below 300ms, or about 1/3 second.
Below 100 hz, Speaker placement and subs are the better solution. EQ is most useful below 80hz. Your room is a system like your components. You have to work with various elements to optimize it. REW can help but I find a real time analyzer to be important as well. With a live 1/3 octave display, you can walk around your room with a calibrated Mic and see what's going on. Then you can try different solutions and both measure and more importantly, hear the results.
Just wanted to update the thread about the results of playing with the listening position based on suggestions from forum members (on another forum).
The suggestion was to follow the rule of odds in speaker and LP placement. This resulted in putting my speakers with front baffles 37" from the front wall (1/5), 28" from side walls (1/5), which placed them roughly 80" apart.
The original suggestion was to have my listening position (LP) 5'/60" from the rear wall. I took a FR measurement there. But this LP moved me pretty far forward from my Atmos centered LP, so I took some additional measurements moving further back toward the back of the room in ~6" increments.
If we zero in on the 55-60Hz dip as a reference point:
The blue (lowest trough) is the 60" off back wall LP
Next higher green line is 52"
Next two higher lines (purple and bolded yellow) are ~46" (I tried to replicate this with a second measurement later, was probably an inch or two off from original position, but it's close)
Highest brown/gold line is the near-original 40" off back wall LP (I think I originally started at 38")
My observation is that the LP doesn't much affect the 35Hz or 95-100Hz peaks - they're pretty much there and similar in magnitude regardless of LP within this range.
The 55-60Hz dip though is pretty heavily influenced by LP with it filling it more the further back the LP moves toward the back wall, but this comes at the expense of creating a new dip at ~180-190Hz, which isn't as deep as the 55-60Hz one, but it's definitely a trade-off.
Based purely on this comparative FR curve, I think I like the bolded 46" off the back wall response the best. It fills in the 55-60Hz dip to within -3dB and keeps the 180-190Hz dip it creates to within -3dB as well.
So if I stick with this, I just live with the -3dB dips and experiment to see if there's anything in the way of reasonably priced room treatments to reduce the 35Hz and 95-100Hz peaks.
Does this seem like the best compromise and an overall "good enough" room environment to not have to spend money on expensive room treatments or digital room correction?
I personally have found that digital room correction does a lot more than room treatments, but I listen to digital sources primarily and the OP is mainly analog.
Bass was a constant issue/problem for me when I had larger (mostly full-range) bass reflex speakers. Switching to still large but somewhat lower range limited (down to 40 Hz) acoustic suspension speakers with dual large’ish subs gave me tremendous flexibility to tame bass response issues and resulted in much better sound across the board.
For you folks implementing active correction, once you do the evaluation, how is the active correction implemented physically? Do you need to run the signal through a DSP device? Doesn’t that add noise? I do not see too much about active correction in these forums but maybe I haven’t been looking.
I'd never use dsp on an all analog system, except for subs which is practically a necessity. My experience is all the dsp software I've tried has negatively altered the presentation such that it sounds less 'natural'. Roon dsp atrocious, HQPlayer much better, still, prefer room treatments in my dedicated room.
Yes, I'm kind of leaning against considering that the room seems "good enough" now that I've tweaked listening and speaker position.
To do a MiniDSP w/DIRAC Live experiment would be $500 minimum and to do a more sophisticated custom filter would require inserting a computer into my setup to run the more sophisticated DSP - that's $1000 minimum. Either of which would add an ADC/DAC step.
@captouch Mitch creates a DSP package called a Convolution Filter. He uses some very expensive audio software to do this ($20k). This software is way more powerful than any physical audio gear that is inserted in a processor loop.
As I mentioned before the Convolution Filter is a digital only solution. That is your CD player, and tuners are out of luck. It only works with a DAC.
You install the Convolution filter on a music server, which is a computer. In my case, I use ROON Core on a cheap computer and install the filters on that ROON Core server. ROON has a GUI to install the filters. The filter is in the signal path (not sure if that is bad) and applies the filter BEFORE the bits are sent to the DAC. Your streamer sends the modded bits to your DAC. The DAC is connected to your preamp.
In my opinion the best way to do DSP (but only digital sources)
BTW - what I describe in NOT ROON DSP. The same filter can work on JRiver which is completely different from ROON.
@yyzsantabarbaraThanks for the explanation. I wrote to Mitch and we exchanged a couple of emails.
He referred me to a device that could be inserted into a processor loop and interface with a computer to make it work on all sources, though it was an open question on whether the device would play well with my particular process loop (impedance matching and all).
It would be an over $1100 solution for everything which could be worth it if there were no other ways to address my issues.
But I do think my room is shaping up to be okay after all. And Mitch said if I changed my speakers (which is always possible), the filters would need to be redone, so I need to be sure I’m both settled on my endgame speakers and have remaining issues that keep me from being happy with the sound without DSP.
OP, for a reasonably inexpensive DSP solution with more potential tricks in it's bag of, you might look at a Behringer DEQ2496....everything in a tape loop that you could potentially want and then some. The calibrated mic it uses costs 25$....
I've 2 of the older 8024s' that allow me to 'run flat' in a variety of spaces they've been in without treatments....not perfect, but what is?
Sweetwater for new (free shipping); used might be 'out where, somewhere'...hard to mess up an eq.
Steep learning curve, but you'll learn a lot in the effort....:)
For the record, room treatments and room correction are not equivalent.
Using a frequency response curve to determine if you need room treatments is only useful in the bass. Above that the microphones won't integrate frequency response measurements over time the way we do. You need time based plots for that.
Now, as for EQ / Room Correction... the best you can usually do without bass traps is to clip peaks. After that you raise the overall level of the bass to taste.
With bass traps that are effective at your problem frequencies you can mitigate both much better.
Point is, for your bass, use the simulator to make sure your speakers and listening location are away from the room modes you are finding. Consider placing bass traps near the areas activated by those modes.
As for the rest of your speakers, leave them alone, but in the mid to treble regions having appropriate mid/treble absorption and diffusion helps greatly with imaging and comfort levels. Also taming reflections (which won't show up in a frequency graph) will make the room sound like you have much more bass.
If I wanted to take time based plots, is that doable using reasonably priced tools, or is that a pro assessment job?
I did move my speakers to the 1/5 position from front and side walls, and LP to 1/3 position from back wall. Seems to have helped some. I’ll post the resulting curves soon.
I do have acoustic panels that I think could work for the mid/high frequencies. Had no idea the FR curve and REW program was incapable of picking those up.
Do you have to spend big $ on something like GIK bass traps, or is there a more cost effective option vs spending $500 per bass trap - that can add up quickly!
Also, off topic, I had tried to send you a private message to ask about speakers as you had commented a fair amount on a particular brand and I wanted to ask your opinion on some things. But I got a weird message about a moderator having to approve my message - not sure it was ever received by you. Just sent another message now to try again.
Here's the freq response curve with my listening position about 5ft/60" into the room, which is at the 1/3 point. Speaker baffles are at 37" from front wall (1/5) and 28" from side wall (1/5).
No toe-in currently.
1/3 smoothing, normalized to 75dB at 1kHz.
If I use +/-3dB as a criterial, there are those two peaks at 35Hz and 95Hz, big dip at 58Hz. Not sure how badly these big peaks are potentially degrading the sound. Besides that, a 4dB peak around 650-900Hz, but the rest of the FR curve is within +/-3dB.
This is sitting further toward the back wall at 51" instead of 60".
The 55-60Hz dip is reduced some, but overall it seems a little less smooth than the 60" FR esp from 200-600Hz. Subjectively, it seemed to me that 51" was a little clearer, but the vocals a little less warm. Not sure if that's consistent with what you'd expect from the FR curves.
Here are the two superimposed on each other. . .
On another forum, some members thought it this was workable and I could just go with this based on where the peaks/dips were, with 60" being optimal.
Finally, here's even further back at 45" (compared against 60" as a benchmark):
Here, the 35Hz peak is increased, the 58Hz dip is pretty dramatically flattened out, but the tradeoff is a dip created at 180Hz.
Not bad. I always apply 2) DSP to flatten things out further after 1) room correction. . Then finally a third layer of DSP 3) to adjust to my personal preferences, and roll off any wasteful low end to help out the amp and steer clear of clipping, if needed. That pretty much covers everything. Older ears may be well served by ramping up the high end a bit. A hearing test can help determine. I use Roon for this and may end up with anywhere from 1 or 2 to as many as 7-8 distinct filters per Room, including a single convolution filter for the room correction part. Works great. Sound is fine tuned in the end exactly to my personal liking which is what it’s all about.
Always do what you can to set up the room well to start. Then DSP away towards your own personal sonic bliss. Make good buying decisions to set up and integrate everything well up front then anything is possible with DSP from there.
If I wanted to take time based plots, is that doable using reasonably priced tools, or is that a pro assessment job?
Room EQ Wizard (REW) has a variety of tools for that, and their forums are very helpful. Here’s a starter page.
Let me give you a little more background. For frequency response REW and similar tools (I use OmniMic) gate the signal above the bass. That is, they stop listening a few milliseconds after the impulse start to arrive. This deliberately excludes as much of the room as possible to get the response of the speaker. The sound waves are still busy traveling back and forth around the room for a much longer time period than this.
Our ear/brain mechanism does not hear like a microphone. We don’t stop listening, but integrate the experience of the direct sound and the reflections over time and this fully integrated perspective is what gives us an impression of the tonal balance. Often audiophiles only think this is an imaging problem but there is a very significant effect on the perceived tonal balance.
If you ever hear Fritz speakers at a show, he travels with only a few absorber panels. He knows what he's doing, and that his speakers will sound more full that way. We should all take a lesson.
In a very reflective room where the mid/treble bounces around for too long our hearing tends to exaggerate the mid and treble frequencies, so as a result will sound as if the speakers lack bass. So, a tip I often give which people resist is that adding mid-treble absorbers and diffusors will improve the apparent bass, and none of this is captured by simple frequency response plots.
The other thing these plots fail to capture is how having multiple direct reflections, and / or the absence of the right diffuse sound field ruins the illusion of an audio image.
In the bass things are different. The wavelengths are so long that it’s nearly impossible not to integrate the room, so as a result your frequency measurements are integrated. Speaker builders always face a challenge with this and use a variety of techniques to try to get the real speaker measurements like putting the mic 1/4" in front of the drivers, measuring outside, etc.
While room correction software may do a lot for the bass and maybe even correct for perceived extra mid/treble they cannot stop reflections. That’s why in my mind the two approaches are not equivalent but complementary.
It occurs to me you are using gating and smoothing. Turn those off and re-examine your measurements. I think you can re-use what you've already captured. You'll see a much nastier image of your results.
Also, when comparing speakers, it's very much worth measuring off-axis to see how good of a sweet-spot they would provide. Speakers that measure similarly on-axis may be crap off.
Guys, really? Sorry to tell you OP that graph posted has a terrible response, about 20dB difference between the major peak and null. The null at about 58Hz is 12dB below the average. That’s a lot of musical information being lost in the most important range. The huge peak at 35Hz taking much longer to decay than the rest is going to make the bass slow and boomy.
I don’t agree with DSP. How can it reduce the long decay times and it can not et rid of that null. No matter how much power you pump into it, it will just cancel with the same power.
You can push the furniture and speakers around all day and you will still have peaks and nulls only at different amounts and frequencies. All rooms. I say again, all rooms will have these issues.
To achieve a smooth response some absorption is needed to avoid long decay and address bass problems with at the very least a pair of subs. They do not need to be the same brand nor size but avoid ported subs and they must, must have variable phase otherwise you’ll be endlessly pushing them around the room. Any ports that resonate at only one chosen frequency complicate matters further. You are adding a frequency invariant bass source with no way of tuning it.
OP I commend you for having the ability to measure as it’s the only way to remove guesswork.
@erik_squiresThanks for spending the time to thoroughly explain those issues. I can easily turn off smoothing, but at some point, the curves get so crazily jagged (with no smoothing), that I'm not sure what I'm supposed to take from it.
I haven't figured out how to turn off gating yet. Trying to research that now.
@lemonhaze Thanks for your input. When you say "some absorption", do you mean bass traps? If so, are there more economical solutions than the $500/bass trap solutions from GIK?
Yes, with minimal treatment of the room, there's a definite tradeoff between dips at 58Hz and 180Hz. If I move my LP so the 58Hz dip fills in a lot, it creates a smaller dip at 180Hz. You can see that 5 posts above in the 60" LP vs 45" LP.
I do see that 35Hz peak in the many of the plots posted by other people in different rooms, so that one seems common. The other ones seem more variable and a matter of trade offs.
In a room my size and filled up with record, CD, and gear cabinets as much as it is, I think it's honestly unrealistic to entertain getting two new non-ported subs. I understand there's a proper way to do things, but I think the question for me is what gets me close enough or good enough to live with while still keeping my room as usable as possible.
Because if getting things closer to ideal requires my stepping around subs or having to contort to access my media because a sub is blocking clear access to a rack, then it's going to be a daily irritation. Not sure I mentioned above, but this room is also a TV room with Atmos in-wall/in-ceiling speakers, so I'm admittedly trying to do a lot with the room and one of the consequences of that may be I'm not going to be able to do things as ideally as a pure 2-ch listening room.
I do have a single HT sub (SVS 10" ported sub) and I could dual purpose that if it would help. It does have a phase dial. Since I'm using older gear, I'm going to need to sum my stereo signal to mono and then route it to my sub (no speaker level inputs on my sub, just a single RCA). I could play around with that and if I see the potential, maybe I start to think about how to move some things out of the room and consider a couple of ported subs.
But the room just isn't all that big to begin with unfortunately.
All that being said, I am open to room treatments, preferably beginning with ones that are highest bang-for-buck and seeing how much that improves things before going too far down the rabbit hole and diminishing returns.
Turnimg off smoothing and gating, of any, is pnly useful as a learning exercise. I wanted you to see hpw much filtering was being done for you and why this measurement only answers part of ypur question.
The link I posted to GIK acoustics will send you on your journey
Overall, if you did this ONLY with EQ, I'd flatten the 35Hz and 95 Hz first, and then raise the entire level bellow 150 Hz to taste.
Bass traps are a good idea, but may be too expensive. Adding a subwoofer in the right location, with the low pass filter set high could also help. May take some experimentation, adds more hardware and of course, is expensive too.
@lemonhazeHere's an alternate FR curve at 48" (bolded line) vs 60" (which was what was previously recommended to me as best of my alternatives).
48" reduces the 60Hz -11.5dB dip to -4.5dB, but the 180Hz dip is increased from -1dB to -3dB, a 300Hz +3dB peak is created, and 550Hz goes from +3dB to +5dB.
Overall, 48" seems a little more peaky, but the benefit is filling in that 60Hz trough pretty substantially.
@captouchhave you tried as close to the front wall as possible to see how that looks? Close enough that your speaker cables may touch the wall but not be deformed
@kofibaffour while the front baffles are 37” from the front wall, I have cabinets in the front that gear is set on/in. So there’s very little space between cabinet front and speaker back as seen in pic.
This means I can only open one side of cabinet without moving the speaker, which I’m okay with as I don’t have frequently used items in there.
But it’s pretty much a non-starter to move these cabinets off the front wall as there’s no other place to put them in the room and I need the storage space.
@captouchoh then I guess you gotta use the best fit that gives the least dip in the below 60Hz region. I thought it was just the front wall bare behind your speakers
@captouch, yes I'm talking about bass traps which because of the long wavelengths involved need to be large. Mine run floor to ceiling and are 3ft. across the width. It's a standard 600mm x 1200mm x 50mm rockwool or glassfibre board cut in half = 2 off 600mm x600mm squares then cut across the diagonal. If you are handy these things are simple to build inexpensively especially if you have demolishers nearby. I have picked up a truckload for 20% normal price and even some for free. Google DIY superchunk bass traps. These are to be placed in corners, any corners where walls meet including the floor/wall and ceiling/wall corners but is usefull just about anywhere. I helped a friend with a difficult room that had a deep recess that was used as an office and tunk receptacle which housed the vacuum cleaner, some suitcases and kids toys including bikes. I suggested filling with rockwool and made a framed rattan panel which looked very smart. A ceiling cloud acts as broad-band absorption and is useful down to mid bass frequencies.
You have a SVS ported sub with variable phase, great. I have the sealed box version. Two subs work well and will provide a much smoother response than just one. I suggest you position it where it is not an inconvenience, anywhere really and using REW dial it in to give the smoothest response, then plug the port and notice the change, now tweak the settings somemore. With the 2nd sub, again place it where it is the least intrusive perhaps even using it as a side table. Tweak again for smoothest response which will mean returning to the first sub for a little adjustment. By now you should have a plot that is vastly better to look at and to listen to. You will begin to understand why I avoid ported subs. Of course plugging the port on the SVS may produce a smoother result but that then is sheer luck.
Bass traps are hated by most who don't understand what is at play feeling they want all the bass they can get which is antithetical to trapping bass. Well looking at your frequency response you are missing a fair amount of bass. The bass traps absorb some of the low frequencies that build up particularly in corners but not exclusively. They help reduce the severity of room modes and standing waves.
There is a paradox here in so far as bass is being absorbed but more bass is heard. Prior to obtaining a smooth response the nulls apparent in your plots is revealing the frequency and the amount of bass absent from the performance.
Using Bass Traps and multi-subs together is a revelation. You have now effectively removed the room's acoustics from the performance, like listening to headphones, and are hearing the musical event. No new component nor DSP can achieve this.
Please report back and tell us what you saw and heard by plugging the port.
Question for the group here. I tried, just for learning purposes, to use my SVS sub to see if it would help fill in that 60Hz dip. Here’s the FR curve. While it did fill in the 60Hz dip, it blew up the 35Hz peak more.
The phase is set to 90 degrees on a variable dial that goes 0 to 180. My question: would playing with phase at all help this curve?
And a more general question, what is causing this 60Hz dip? Cancellation of sound waves at 60Hz, right? Theoretically, if I put big bass traps in the back corners of the room, does that solve this issue as well as potentially the 35Hz and 100Hz peaks? Or is it not that simple?
Did you try plugging the port on your sub? Just push some foam or a sock into it. Yes of course playing with the phase (timing) will change the curve, that’s the whole idea. Get a second sub.
Does your SVS sub not have the ability to adjust remotely from your phone? There is more than phase to adjust. You need to also vary the output SPL, Raise or lower the crossover frequency, Change the slope of crossover from 6dB/octave to 24dB/octave, vary the Q and room gain. If you change any of these settings then go back and adjust phase again, and so forth.
Bass Traps? from my post above: The bass traps absorb some of the low frequencies that build up particularly in corners but not exclusively. They help reduce the severity of room modes and standing waves.
It appears you did not comprehend my long post trying to explain all this so the best advice now is to learn from the masters. Look at articles from Earl Geddes, Floyd Toole and Todd Welti on multi-subs. Fussing around with DSP will not get you there.
The issue is I have very limited adjustments on my sub. See pic below:
So I can adjust phase and level, but nothing else.
I was also having some issues getting REW to output to mains and sub at the same time. So when I played with phase using sub output only, it didn’t change anything because I think it’s the phase interaction with the mains that will cause different responses to the FR curve. Just changing phase if the sub is the only thing playing the frequency does nothing to change the FR curve.
You got a few issues going on. Think you have a couple nulls going on.
The bass energy spike 30-40 is huge, then that massive hole at 50-80. Some peaks in the middle, with treble dropping off.
This tells me you have a boomy setup, with bright mids, and low highs. DSP will not fix this, just adjust. Don't think you can room treatment out of this.
Your speakers are in the wrong spot, or your listening spot is totally off. Think you should move the speakers around. It looks like the walls are enhancing the low bass, nulling out the mid-bass, the room appears to "dark" already with the highs. Maybe remove a couple of panels, or move them around the room.
Do you have any tones controls active? Turn them all off, if you are taking readings, then adjust them after the readings.
The 35Hz spike is there regardless of speaker placement and LP - varies a tiny bit in magnitude, but not much. Room is 11.5’ wide by 15.5’ long and 8’ high. Probably a characteristic of the room.
The 60Hz dip can be filled in at the expense of creating a more shallow one around 180Hz.
The speakers are places 1/5 of the room length from the front wall and 1/5 of room width from the side walls. It was recommended to place the LP about 1/3 room length from back wall (60”), but I found I preferred my LP 54” from the back wall.
No tone controls active. I’m using Pure Direct mode on my AVR to bypass the Audessey room correction. I’m only using the AVR for the sweeps because it can accept the HDMI from my MacBook. Normally, I use a McIntosh C35 preamp that has a 5-band EQ, but I normally listen flat. Sometimes with a small bit of loudness contour, but mostly flat.
OP, let me apologise for assuming your SVS sub could do what I mentioned. Looks like you’ve got one of those early models. I’m using an SVS SB 1000 PRO which sells for about $600 and has a very useful feature. Download the App and you can adjust all the parameters I mentioned from your phone but forgot there is also a few bands of PEQ. Check out their site. This is the sort of sub you need. There are other good subs available but the SVS is great value and I prefer it to my REL which has 0 or 180 degree choice so means I have to keep trying different places to get it dialed in.
I am using OmniMic to measure and I am not familiar with REW which essentially does the same thing. I play a CD with sweep tones and have the mic. at my listening position sampling the combined sound of the speakers and sub/subs and while changing settings on your phone you can watch the frequency response change. The second sub will smooth the response even more. REW will also display RT60 as a waterfall plot (CSD), the time it takes for the sound to decay by 60dB. The average room will be about 300ms.
I have 2 large floor to ceiling bass traps, broad-band absorbers, extra heavy curtains plus 2 subs and the bass is dynamic, very detailed, informative, clean and powerful.
A point that I may not have properly addressed earlier is that the benefit of a sub in a situation like this is not it’s bass output but the ability to move it to an ideal location. However if you are severely space constrained, then a sub is almost useless.
TO place the sub you’d put the sub in your listening location, then move the mic around potential locations until you find the best measuring place. That’s where you put your sub.
My earlier advice to clip the peaks and lift up the entire bass region still stands.
If you can’t do this and your sub is generally where your main speakers are there’s no point.
I’ve posted pics of my room in other threads w.r.t. other questions/topics, but it might be helpful to show what I’m dealing with here.
Front of room:
Right side of room with entry door in middle of wall:
Back of room:
Left side of room:
I can remove things like the single speaker in the back, the beverage fridge, as well as the “side table” to the left of the chair. But all the record racks and wall cabinets for CDs are my media storage and have to remain in the room. The front cabinets both hold gear (active and spare) and I really prefer not to replace them.
So it’s a crowded room filled with “stuff”. The sub is currently within 6” of the back wall firing toward the left wall is the room with records in rack about 42” away. The speaker front baffles are about 3ft from the front wall and near the cabinets, which prevents the inside doors from swinging open without moving the speakers. Which is fine, I can deal with that.
But my options for placing a sub are limited to the remaining periphery of the room, which means to the right of the record rack on the left wall near the window, anywhere on the back wall, or I could use it as a side table in place of the 1x2 cubby I’m currently using as a side table. I suppose also on the front of the room between the main speakers as well.
I’m already somewhat having to step around things in certain places to access the records. I’d prefer not to place the sub somewhere in the middle of the room and have something else to step around.
So this is what I’m working with. No complaints as I’m trying to do a lot with this room and the agreement with my wife was to store all my media and audio gear in my room to avoid clutter in the rest of the house.
But there are somewhat limited options left for placing the existing sub or adding a second one.
Sorry for the possible distortion in the pics. They’re 1.33:1 aspect ratio and I’ve tried to plug in the numbers to preserve the right proportions, but it posts them distorted once I actually post and view in portrait mode on my phone. When I turn my phone into landscape mode, the pics look like right and undistorted.
Ok, I need to add one more important thing. In the past couple of days, I’ve decided to at least try bookshelf speakers in place of the Monitor Audio Gold 20’s.
Part of this is because I am wondering if the Monitors are still too big for the room and the bass output qty is still too much. And part of this is just me being curious about whether bookshelf speakers can satisfy me as main speakers - I’ve been resistant to this in the past because I’ve always seen bookshelf speakers as “too small”.
But the reality is my room and free volume in this room is also small, so a bookshelf may be the most appropriate sized speaker for my situation.
While it’s by no means a given I’ll like the bookshelves and that they’ll become my main speakers over the Monitors, it’s very possible. I anticipate the FR curve and overall interaction between a different speaker and my room will be different as well so wanted to give the thread a heads up so I’m not exercising people to help me find a solution for a problem that may possibly change.
So it's worth using the AM Acoustics simulator to see where your room modes are, but one possible solution would be to run soffit traps actually in the soffits. If the modes are vertically in the corners though you'll want to put them to the side of the TV.
@captouchthat looks like a great music room. Think I understand better at what is going on. Everything looks a bit compressed, and yes, the room is filled.
You might have a lot of speaker/power for that room, but that's ok. Had a thought, if you can get a wireless connection to your sub, find the room nulls, put the sub in the nulls, it might cancel out the room null.
On the other hand, with your gear and that room, do you even notice the dip? Is it deep bass heavy? Do you feel the room is dead or alive? As most of us have realized, measurements don't always mean much to our ears. If it sounds good to you, then it's good.
This is part of the reason why I don't want to measure my room. It's all analog (sans streamer), Done all the old school things, and it sounds good to me, so it is good.
In my experience, room correction with DSP (MiniDSP+DiracLive) made a huge difference. In terms of sound, it went from fatiguing to blissful. The bass became more coherent, the mids and highs less muddy, more clear. Instruments and voices became separated, imaging dramatically improved. DSP is not simply about correcting issues with frequency response. As previously mentioned, time domain problems can also be corrected, which I assume is why the imaging has improved so much.
Below is my frequency response, measured with REW. Yellow is with DiracLive turned on.
And here are the impulse responses as measured with REW, before and after correction with DIracLive.
My perception is that the magic comes with both the frequency and phase corrections that come with DiracLive implementation.
Before MiniDSP, my room was treated with some absorption panels, mostly to reduce some of the reflective wall surfaces to improve reverb. The room includes a 77" TV, couch, furniture, large and dense wool carpet, and sits in the basement where two of my walls are concrete covered in sheetrock and insulation. Speakers ('bookshelf') are 5 feet from the front wall, about 3 feet from the side wall (right, concrete, a little more open on the left side).
@mswale I think if I wanted to move my sub around to cancel the nulls, which I think is a good idea and ideal, I’d want to get a smaller sub. The SVS was from my old HT system in a bigger space, and while no problem to reuse for HT in my new smaller space since the AVR will use Audessey to adjust level, it’s not an ideal sub for music.
I don’t notice the dip or that anything is lacking, but it’s probably one of those things where you don’t know until you hear the alternative.
But as mentioned above, I’m going to try bookshelf speakers first before getting a new sub or committing to room treatments or digital room correction. The Monitor Audios that I’m using now are spec’d down to 30Hz. The new bookshelf speakers are spec’d down to 38Hz. So they’re bound to create less of a 35Hz peak if they’re already down 5db or more at that frequency. At least I think.
When I measured my friend’s Electa Amator II’s, which are spec’d at 35Hz or so, there was still a peak, but much lower in magnitude. I’m sure I’ll still have the 60Hz dip and 180Hz dip tradeoff to some extent, but the overall balance of the FR curve may give me more speaker placement and LP options to help me find a better balance.
@atp001I’m curious about trying something like Dirac Live - the price for entry just comes at a hefty price tag and the input I’ve received from this and other forums is that it could help in some aspects, but can’t help in others. I think I’ll wait until measure and listen to my new bookshelves and see where I am after that.
It was suggested I try the trial period of Dirac Live, I just need to figure out which EQ software also has a trial period that will allow me to use it with their software and target curves. I haven’t had the time to do that yet.
I have implemented DiracLive three times, on both sides of my basement, and in my living room. The sound improved in all cases. But, I think optimizing the speaker placement and/or LP (and possibly room treatment?) before using DiracLive will get the best results.
One element that should be considered is bias towards your current (non-corrected) sound. I would live and test the room corrected EQ for a little while before making any conclusions.
The cost of MiniDSP + DiracLive is not large relative to your total system cost or cost of room treatments. IMHO, best bang for buck I could ever spend. True, tactile improvements in sound that could not be achieved with upgrades to components, cables, or recording type. One could argue that DSP also corrects defects in speaker response (frequency and phase). Sorry for sounding like a salesman, but this stuff has really changed my perception of what good sound is and how to achieve it.
Just curious, what elements of sound reproduction can DSP not correct? We often hear that room modes cannot be corrected since they are a function of how the sound interacts with the room after leaving the speakers. I would not be so fast in making that assertion. By modulating the phase of the individual channels separately, should it not be possible to also correct, at least to some degree, constructive and destructive interference? I believe this is what DiracLive is capable of, but to be honest I am not sure since they are a little vague in describing how it works exactly. I would love to hear from someone with more technical knowledge on how DiracLive works.
You have a very attractive room, small but certainly capable of being tamed with a pair of subs and a large bass trap. A small room needs lots of absorption, a large room needs lots of diffusion and a mid sized room needs some of both.
As I mentioned in an earlier post you could use the sub as a coffee table but the photos reveal 2 obvious places that will not only not get in your way but are generally from the many installations I've done the preferred positions.
First Sub: On the left wall below the window and tucked up close to the record rack.
Second Sub: Behind the couch slap in the middle of the back wall.
The obvious place for a bass trap is horizontally on the back wall where you can accommodate a full size superchunk design. See photos below, only you would build it horizontally.
I also suggest you take 2 or 3 of those slim grey panels and fix them to the door and replace them with 4" thick broad-band absorbers. To help further, consider adding heavy drapes/curtains across the window. They can be drawn aside of course but closed when needed.
Your main speakers' bass output will naturally contribute to the chaotic bass propagating around the room and by moving them only small amounts can fine tune the resultant response. Just a couple of inches.
The lone speaker at the back can be left right where it is but you should short out its speaker terminals with some wire. This will damp cone motion from pressure waves causing the speaker to act as a microphone and driving power into the crossover then releasing that power out of phase and time with music
Having the main speakers overpowering the room is a fallacy. With the room acoustics sorted this is not an issue.
Regarding your post above, changing speakers are not going to sort out the issues you are experiencing. Prove this to yourself by plugging the ports on yor main speakers which will effectively render them as sealed boxes and have the bass response roll off earlier at 12dB/octave. This will immediately show up on REW and it costs nothing but a little of your time, it's also informative. There is no need to settle for a ragged response. In one of the photos you can see a DIY absorber that is usually 4" deep but I made these 5" deep for them to work lower in frequency. My wife said she does not want me to go 6" deep.
You can also build a ceiling cloud to suspend from the ceiling which is very effective. Use REW to check your decay times as I mentioned in a previous post. This is a scientific approach to sorting out a room's acoustic problems which each and every room suffers from regardless of shape or volume. Fact.
Start of bass trap left front corner.
Bass trap waiting for cover to be attached with velcro.
Bass Trap right front corner finished with cover on and heavy drapes visible
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