How to Calibrate Multiple Subwoofers Using REW 

Hey Gene, I know this is an older video but I finally took the plunge into MiniDSP and your plethora of knowledge in terms of proper measurement and EQ usage has allowed me to really dial in my subs. You’ve got no idea how much you’ve helped me man!

3 years later and this video is still one of the best ones to help with rew

Who the heck disliked this video? If you chose this video based on the description, it delivers. Some people are never happy I guess. Thanks for the video Gene!

Great tutorial. It really helpful to see how the test parameters affect the display. It is also heartening to see the back wall opening to the kitchen; one of my side walls opens into the kitchen likewise. The advise to measure only around the central listening position, where to aim the mic, how to interpret hills vs. valleys and what EQ can, and can’t do for you. In 2023 I’ve ordered the OmniMic V2 to help me tune my room, and finally, finally, integrate my subwoofers into my room. You’ve given me hope after 10 years of frustration with home theater setup (I had about given up).

Yes. Most important piece of enlightening information heard here is "good easurements at the critical crossover point between speakers and subwoofers!" This is rarely discussed, yet absolutely important(besides flat response) Good job Gene

Great tips Gene. Thank you very much. All the Best from Poland.

OMG YES! Cant watch the vid yet but saw the title and Im so stoked! This is perfect timing, just while I was tinkering with my dual r115sw’s and minidsp again! 😃 I still come back to many old vids, so much truth and knowledge in them, reckoning this one will make a fine addition!!

I added a 3rd sub to my home theater and it blew my mind what a huge difference this made for my listening area. The freqeuncy response without any smoothing is nearly perfectly flat (all around +/- 3db/5db) all the way to to 120hz (xover point). This video helped me so so so much! Incase you're wonder I'm using 3 SVS SB-4000's and I have zero complaints with their performance. It's actually SCARY sometimes...

Thank you for sharing know how! Wish you all the best, Genius Gene!

Love seeing this type of content.

Great video! Hope to watch the ARC video soon!

Really cool. Thks. The actual adjustment for my mother and law would be at the toilet sit :)

Hi Gene, I’m running 2 SVS SB1600 ultra’s and I’m running a 5.2.4 set up. I’ve run REW a few times with good results, but I’ve never adjusted the phase. I’ve used the the EQ on the subs to adjust out peaks and nulls. You had mentioned not to worry about the nulls as much as the peaks because you wouldn’t notice them as much. I was doing that all wrong. I was boosting the nulls. Now I going to redo REW and try adjusting the phase and see how that affects the curve. Side note I want to add just by moving my subs 6 to 12 inches made a huge difference on my REW curves. Thanks for putting these videos out. I don’t think I would have attempted REW without them.

Hey Gene thanks for this, increasing the LPF for LFE from 80Hz to 120Hz made a huge difference in sound for my room. Now thinking about trying the calibration for my two subs.

Thank you so much for taking the time to make this video. I've been waiting for you guys to help us out. Thank you so much.

Thank you! Recently bought my fourth 15in. and tried to do with Audyssey.

Thanks for this !

You're awesome Gene! Thanks.

Great video, thanks!

I've had My REW mic. for maybe 5weeks. I really need to get on with it.

Looking forward to the Audyssey video!

Great video, thank you.

Gene, how does MiniDsp affect what's been layed out in this video? Can you perhaps do another video showing us how to use REW and MiniDsp to EQ, align and bass manage multiple subs? Really appreciate your channel and all the helpful tips

While playing around with REW what I found out first is checking whether dual subs are in phase each other by listening around the room and whether response curve is satisfactory enough between 20-80hz. Once that's done I missed the point Gene try to come across from 10:15, is that check if dual subs are in phase with main speakers at the crossover region around 80-120hz. I had a dip around 80-100hz and mistakenly boosted DB, so instead what I did was changing both subs from 0 to 180. It did the trick while also maintaining similar response from 20-80hz.

This is great. Thanks.

"that's where you put the mother-in-law" ... omfg LMAO ... but so true. 🤣

Thanks for the great video Jean. Big fan of audioholics and the information you guys put out which is very helpful. I followed your other video with the MiniDSP in the bigger Room where you have the 5 subs, and that was awesome work as well. My own setup is a 7.3.4 atmos setup in a dedicated theater room. The bass is tweaked using the MiniDsp 2x4, REW and a program called called MSO which is awesome, FREE and works similar to the SFM software from Harmon. I truly believe that the MSO program could help you achieve the same tight consistency seat to seat with half the time spent. You may want to check it out.

Fantastic advice:)

Awesome information Gene!! I'll be watching this video probably 8 times... 😂🤣😂

Thanks so much!

Excellent video. Many thanks for the share. Could you please shed light on time alignment using acoustic timing as reference in REW using a USB Mic?

So I have done some sewwps in my home recording room. Totally amazed with the results. I lost a little bass volume however the frequencies felt better to me. Would you say I could turn the sub speaker up a little to comensate?

Good video Gene I have the MINIDSP microphone its good for me to see this if I did mine correctly .I am in a condo living room so different from a house .I have two subs .IN my setup. I saved my charts from the mic .I can always go back and see .

The microphone I have is the miniDSP UMIK-1USB. I have dual SVS SB-16 Ultras and a DENON AVR-3313ci receiver.

Please help me in how to adjust the frequency gain information in to audyssey multi EQ.

Thanks, what about Dirac? would you recommend only measuring 3 feet max distance apart?

Thank you for sharing......

Can you do a video on how to use REW to set the eq that’s built into a home receiver?

Hi can you make a video on how to calibrate a home theater system running separate amplifiers on all channels,thanks

Very interesting, I think everyone with this hobby tries some version of this. Frequency resp. is much more audible than phase or group delay? Does the Dayton Imm-6 work at all for this?

Nice video. I'd recommend to use ASIO device drivers.

Could u do a video of how to measure properly a fulrange speaker with this mic?

great vid. Can you do a vid for towers and rew. awesome thanks

The most important thing about all this work you're doing is understanding the difference in sound. I think it's a killer-app feature. Receiver manufactures need to program in a way to toggle all settings. I'd love to hear how my changes make a difference on the default (no calibration) vs Dirac and Audyssey. I know you can switch between presets, but I think there are better ways like "no delay", "no SPL", etc. I wanna know where the issues are and what I'm fixing.

Gene you do it again, amazing content!!

Wow. Very nice. So, I humbly ask, how do I set up studio monitors to accurately produce what will be ultimately reproduced after all mixing and engineering is done? Whew....

Thank you for a great demonstration on the use of RAW software. What is your take on Dirac live as an alternative? I like the RAW approach because I believe you can learn more of a complicated process but there is a steep learning curve. I also like the Dirac live software because it suppose to calculate the needed adjustments within a short period of time. Please let us know what you think of them both. I am looking at purchasing a MiniDSP and not sure if I should get the Dirac Live built in version or go with the RAW solution. Thanks.

have you tried using the ASIO drivers? allows you to measure L, C, R, LS, RS and LFE channels

Awesome!!

Hi Gene, first of all, I would like to thank you for your great videos. I’ve been wondering!! We do our very best with speaker placement and DSP to achieve a nice smooth frequency response with the microphone at listening positioned. But when we do further measurements either side of the hot seat things don’t look so good. Most likely we see troughs and peaks here or there. I was wondering whether these troughs and peaks actually happen in real life, such as a concert hall environment if we were to move from seat to seat, then surely the tonal characteristics of a grand piano for example would change somewhat. I should imagine that our ears adjust accordingly and we accept everything is fine. The question is, are we being too fussy trying to achieve a flat response across our seating area? I would be very interested to hear yours anyone else’s views on this. Thank you, Rodney UK. PS. It could be that any tonal (frequency response) changes in a concert hall are much more acceptable then they would be in a small listening room at home?

To confirm, you'll have a follow-up video using the MultEq app to EQ the subs, correct? The app or something like the miniDSP are used for EQ, and REW is only for doing the measurements, correct?

Gene, did you ever make the video regarding the Audyssey App? Great video by the way!

When doing measurements, what does the dBFS mean in this context and what happens when you crank that up?

Hi Gene! Great video with crucial info! Why the -15db sweep level? Thanks

Can you use REW to level match subs instead of using an SPL meter?

How do you adjust the delay? I have a marantz

Do you still use the minidsp in your main system?

Dirac Live only has the option for 1 sub during calibration. Would you recommend using REW to calibrate multiple subs? And is a miniDSP needed for sub calibration with REW?

What volume do you have the receiver on? I usually do testing at 15 on my Marantz 1603. Also, do you want to get the level as high as it goes but doesnt clip? I usually bring up the level in the -15 to -20 range for the sub and my speakers seem to be down closer to 0 to -5 with the same volume in my receiver. Just trying to figure out this correctly as many people dont go over that. My in usually gets to 0.2 -1. Is that normal to be testing the mic to that kind of levels? You're are way different as they are very low compared to mine(volumes)

Are you playing your receiver at reference level when running your sweep? And should I be leveling to 75hz on my mini DSP? Or am I leveling subwoofers for the maximum response ? I’m lost lol

How do you set time alignment and phase on a Denon X4400H? Do I run Audyssey first? Then turn it off and use REW? Then run Audyssey again?

Hello Gene, I purchased the Dayton mic and installed REW. I watched your video a couple of times and the additional one Audioholics had on REW room simulation. Something very important is left unclear. I have an older Onkyo PrePro with Audyssey MultiEQ XT. I have two McIntosh HT-2 subs, placed diagonally in the room to avoid co-location and still maintain a living room. In your video you mention Audyssey and how you need to switch to manual EQ for ideal subwoofer management of some peaks and drop offs in the response curve. However, it appears that ALL prepros do not allow you to separately set manual sub EQ’s in conjunction with Audyssey doing the other speakers. If you have passive subs, without phase control, are you just plain stuck??

If I buy the MiniDSP mic, do I really need the MiniDSP 2X4 too?

Gene, are your fronts the RBH speakers with the granite cabinets? Shane demoed those for me and they have an incredibly wide sound stage, or rather, wide sweet spot.

Hello Gene, thank you for this video. I have a query. Are you still suggesting Dayton UMM-6 Microphone or you have any other model which you consider better than dayton? Please reply.

Hi Gene, I also have the Maurantz 8012 and the Mini DSP HD, would you use both subs out from the Maurantz to the two inputs on the Mini DSP or just the one out from the Maurantz to the Mini DSP? Thanks

any video about Dirac ? :) pretty please

Sigh....ok the title says "how to calibrate multiple subs using rew". Maybe it's me as I've watched this video multiple times and you have only discussed how to use "rew" software to determine the frequency readings on a particular speaker or sub. I must have missed the part on how to use the readings you get from "rew" to implement changes to the avr or amp. There is no info being given on how or what to do with the info rew gives you to make changes to the "Eq" in an avr or amp. I totally respect the fact that your giving your valuable time to us free of charge and I hope I dont come across as rude but I have to tell you this is so frustrating as a "nube". If you could produce a video on how to actually "calibrate multiple subs" and not just how to read "rew" that would be awesome. The info I'm seeking is let's say my subs are falling short in certain frequency curves ,how do I take that info given by "rew" and implement changes to the settings in my avr or amp? If there is a video out there that does this I havnt been able to find it! Lol! I'm will pay money for this info!..lol! Fortunately the gentleman on your video that came after this one on how to use "rew" answered one of my questions. I think his name is Mathew Poe and he straightened me out to understand I need a "dsp" between my avr and subs. But alas how do i make changes on the dsp with the info i get from "rew". My next step is to just hire a "guy" to come calibrate my system as I'm totally cool with just throwing huge amounts of money at my particular problem!...lol! But seriously it cant be that difficult. I think my problem is just finding the right info,as for some reason it either assumed by gentleman like yourself that this is common knowledge or I'm just a complete and total moron!..lol! I would really like to think it's just that alot of "assuming" is going on and not the latter!...lol! Again thank you for your time!

Really helpful info and nice video quality. Im left wondering, is there a workaround if your subs dont support variable phase adjustment? Also if someone already has a usb mic like a yeti or samson, will they be effective?

If I use an audiophile USB cable for the mic will it give better frequency response

It's a bit of an unorthodox approach to setting up multiple subs but the results look good. Better to increase the AVR's small freq crossovers well above 80hz to eliminate any influence. REW says to avoid adding phase/delay to subs individually. Only need to add delay or invert one sub, the closest. And the sub crawl isn't effective across a sub's spectrum and multiple seats. In any event, it's easier to use a single sub output from the AVR, of course gain match both subs, add phase/delay or invert the closest sub to optimize nulls/peaks across the two sub outputs. Restore the AVR's proper crossovers etc. Then use the AVR's configuring function (Audyssey or similar) to match subs (calculates distance/SPL) to the rest of the speaker configuration aside from subs.

Are you mean to use Audyssey setup first , or not at all?

I am curious, if you set a constant tone at your suck pit frequency and go round your room feeling if anything is vibrating? That could be sucking the bass out no?

whenever I do this or level match my speakers with decibel reader, should my sub be at "50%" or in the middle? I tried setting all my channels at 75db(A) and sub at 75db(C) I just want to make sure that everything is set up correctly before using REW (also have UMIK)

Is there a problem having subs of different sizes? Say a 10" & 12" or 10" & 14"?

What mic would you recommend now, 4 years later?

I have same AVR - Marantz SR8012 and using 2 SVS Sb3000 subs - after using MultiEQ app - I get this one Null around 80-90 hZ - what would be the best way to fix or improve that to make it as flat as possible and I don't have much option to move my Subs? Any possibility of me showing you the curves that I got?

Dear sir. Have you made a video describing how to integrate a single sub into a stereo system? I'm thinking of the correct phase, etc. I use the headphone output from my laptop, which goes directly into my preamp via. rca plugs. I have an umik and REW. Kr Frank

Can you do video with minidsp for subs

Is REW just for running base? Btw how ta feeling?

Wow.Wonderfull.Is it possible to connect a graf/equalizer on a av receiver?Is it going to boost and improve the sound quality?

I have avr at 0db, signal from rew at -30 db and my 20-500 sweep starts at 90db then falls linearly down to 70db at 100hz, then +/- around 70db to 500hz. Do I have this setup correct to be getting these readings?

Do you make the phase adjustments and eq ( in svs app ) before or after run audyssey?

I have a Yamaha Aventage RX-A2060 and it gives three options for dual subwoofers: Monaural x 2, front and rear, left and right. I have read many pros and cons regarding running stereo subs (left and right option). It does seem that many experts recommend going Monaural x 2. What is your recommendation?

Excellent video Gene! I am using an Anthem MRX-720, taking single sub output into miniDSP 2x4, then feeding two SVS PB2000 subs. It is my understanding the two Anthem sub outs are paralleled, hence why I use miniDSP for individual level and delay. Rather than use REW, I use ARCs Quick Measure to set delay and level variation between the subs. Question: Is there any technical difference between using the miniDSP delay vs the SVS phase control? If they are the same thing, I could remove miniDSP from chain to simplify things... Although I do find it nice to be able to tweak the sub settings from laptop rather than going back-and-forth behind the subs. Hope I'm approaching this the right way? Your thoughts much appreciated! 👍

Gene, I have a Pioneer SC95 AVR, I have dual SVS PB1000pros, I want to calibrate/tune my subs to their most efficient level by investing in the MINIdsp 2x4HD device and UMC1 mic. After calibrating with the minidsp, does that unit continue to be connected to my Pioneer receiver? Do I continue to use my internal room correction software in the Pioneer?

Hey man please little help i have a monolith 15 sub and i cant find the best spot to my room i try them all but i have a big null in 45hz and some other frequencys i run audyssey i dont have microphone umik1 for example or mini dsp you believe if i took microphone umik 1 and mini dsp to can make some difference to the curve in few months im gonna buy a second one sub but for now what can i do also you have facebook to explain me better there??? Thank you and im waiting your help🙏🙏🙏🙏

Awesome information!! Thanks! One question though - is it preferable to adjust phase directly in the sub or changing the distance in the receiver menu? Thanks in advance

Gene, I have been getting into this lately. I have the UMIK-1 and a mini-DSP 2x4 HD. I had two big peaks and was able to get my line much flatter with delay and REW EQ. But when I ran some demos I really didn't like it. It was bloated and too much all the time. Even though REW is showing me what is wrong, it sounds way better if I leave it there. I am sure fixing these things is great if you really know what you are doing, but for right now Audyysey can do a better job than I can. I say if you are happy with your sound then don't even go down this rabbit hole. If you have someone who can help you then yes maybe...If you hate your bass then yes definitely. I unhooked the miniDSP and just ran back into my 2 sub outs on my 7705...ran Audyssey ( I have been using Audyssey for 15 years and I only do 3. I have done the 8 and can't say it actually sounds better) and I enjoy it much more. I will keep the DSP just in case I ever run into someone who can help but for now, Audyssey is better at it than I am.

Great vid i only have one person set up so don’t care anywhere else so how many spots should i do where I listening would 4 spots be enough?

Hello Gene. I'm glad I found your channel, though I'm at least three years late. Can this alignment process be adapted to the vehicle environment to investigate sub-bass response in and out of the vehicle? In cabin, windows shut In cabin, windows fully open Out cabin, windows open Out cabin doors open

Gene just to confirm you recommend not using auddesy on the receiver at all? Or do that first and then use rew?

Ok I have the minidsp 2x4 hd I have the power hooked to my power conditioner I have the USB into my laptop also have the umik1 plugged into my laptop I have the minidsp input 1 running to my emotiva xmc2 with my 4 subs plugged into the output side of the minidsp I have a fiber optic hdmi cable from my processor hooked to my laptop I have my rew all setup correctly my minidsp 2x4 hd plug-in downloaded connected with everything hooked up correctly I have double and triple checked but when I check ny levels and also when I try to measure I get no sound

can I do this on a stereo sys w 2 subs too or just HT?

Great video. It is worth having two subs, with a cheap receiver that has only parallel sub output? How would I even know, if I have parallel or not output?

Is there a video tutorial on how to for dummies for REW?

Hi! I use just one sub a Velodyne dd 15+ and my room size is 15x15x8. I have bass traps in all 4 corners, rear wall and rear corner ceiling. Do you think i need more subs or is one enough for my room size? Thanks.

Why is my sweep playing through my front towers instead of only my subs, am I missing something?

Dont understand how to setup the dayton mic with rew spl meter is not accurate and test is too loud

Hey Gene how's it going ? This is my first time posting on your channel. And this video gave me the idea ask you a question on powered subs for a 2.1 music only system. I'm putting together my very first bookshelf speaker system, due to room limited real estate. My question is in your opinion which powered sub would be better for for a variety of music. I want to stay in the $500-$1000 price range. Thank you in advance.