• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Sub recommendation with BMRs

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
Looking for a sub upgrade recommendation for my BMR Monitors. Currently using dual DIY kits from GR Research (Rythmik L12 based I think). Need to go down to 1 sub due to space and want it to be something good.

Considering the Rythmik F12/15 or PSA S1512 or something from SVS.

Would a 15” driver compromise any articulation vs a 12”?

Room size is medium living room (12x18x8) using mostly for music but sometimes for movies too.

Preamp is miniDSP SHD using Dirac Live for room correction. BMRs are crossed at 50hz to the subs. Budget it around $2k.
 

ryanosaur

Major Contributor
Joined
Mar 17, 2022
Messages
1,501
Likes
2,375
Location
Cali
Looking for a sub upgrade recommendation for my BMR Monitors. Currently using dual DIY kits from GR Research (Rythmik L12 based I think). Need to go down to 1 sub due to space and want it to be something good.

Considering the Rythmik F12/15 or PSA S1512 or something from SVS.

Would a 15” driver compromise any articulation vs a 12”?

Room size is medium living room (12x18x8) using mostly for music but sometimes for movies too.

Preamp is miniDSP SHD using Dirac Live for room correction. BMRs are crossed at 50hz to the subs. Budget it around $2k.

Don't get confused... Subs that are well designed don't really have a Sound Quality the way your Speakers do. And I own BMRs.
Most modern ID Subs will all behave quite admirably in most regards. Monolith and Rythmik Subs perform quite similarly in most measured comparisons (see reviews of matching sizes of Rythnik Subs at DataBass and Monolith Subs at AH).
I use Outlaw X-13s which were designed by the same company that does the Monoliths, Claridy Audio (now part of another company).

The short version is that there are a lot more Myths and garbage being tossed about than anything. The most important considerations are matching Sub to room size, knowing how deep you want them to extend to, and what you need from a connectivity standpoint and usability standpoint to work in your system.
Also, no, a 15" Driver will not be less articulate. That is in the Myth category.
You may also find that the Mids and Highs of your BMRs will be much cleaner if you cross higher. I found 80 worked best for my BMR Monitors when they were my Mains. I also found that 80 works best with my Phil 3s, the predecessor to Dennis' new Towers. This can be a personal preference I suppose, but I would encourage you to experiment with higher crossovers.

Is that 12x18x8 the total open room volume that the Sub will be exposed to?
 

Chrispy

Master Contributor
Forum Donor
Joined
Feb 7, 2020
Messages
7,751
Likes
5,910
Location
PNW
I did look at this but I’m kind of missing where it tells you what they will sound like. Although to be fair I am looking at it on my phone.
Why would sub range frequencies sound particularly different aside from accuracy and distortion spec?
 

TurtlePaul

Addicted to Fun and Learning
Joined
May 19, 2020
Messages
631
Likes
1,027
Location
New York
It is much more important to ask how and at what frequency you are going to crossover your sub, sub placement and what you will use to correct room modes then to discuss 12 vs. 15 inch. "Articulation" is a myth. For monopole subs, the meaningful measures are max output before distortion and how deep the roll-off frequency is on the low end. Are you high-passing the BMRs?
 

ryanosaur

Major Contributor
Joined
Mar 17, 2022
Messages
1,501
Likes
2,375
Location
Cali
It is much more important to ask how and at what frequency you are going to crossover your sub, sub placement and what you will use to correct room modes then to discuss 12 vs. 15 inch. "Articulation" is a myth. For monopole subs, the meaningful measures are max output before distortion and how deep the roll-off frequency is on the low end. Are you high-passing the BMRs?
Agreed. When shopping, I like to see the 2010 Burst Test, but more importantly are the Long Term Compression Sweeps and distortion components. It is good practice to look at Group Delay and also to check for any indication of port issues.
Set up is so room dependent it's a different story. The best performing subs can be rendered useless by improper setup. Everything from placement to XO can matter.
 

Keened

Senior Member
Forum Donor
Joined
Nov 2, 2021
Messages
329
Likes
219
If space is an issue you're better off getting two 10" or 8" opposing driver models then one giant sub.

Unless you're really trying to get sub-sonics (in which case physical transducers are more useful for static listening) modern 10s and 8s will get you there and having two subs means you'll be able to create more even bass.
 
OP
birkbott

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
I decided to try a Rythmik E15. Will be in the front left corner of the room. Crossover point I haven’t decided on yet. I’ve tried both 80hz and 50hz with my current setup and couldn’t tell much of a difference other than a somewhat fuller sound from the mains whe. crossed lower. Yes I am high-passing the BMRs.

Re: room size there is a cased opening into the dining room (slightly smaller than the living room) just in front of and to the left of the sub position.
 

tw 2022

Addicted to Fun and Learning
Joined
Apr 11, 2022
Messages
878
Likes
742
I decided to try a Rythmik E15. Will be in the front left corner of the room. Crossover point I haven’t decided on yet. I’ve tried both 80hz and 50hz with my current setup and couldn’t tell much of a difference other than a somewhat fuller sound from the mains whe. crossed lower. Yes I am high-passing the BMRs.

Re: room size there is a cased opening into the dining room (slightly smaller than the living room) just in front of and to the left of the sub position.
I agree with Ryanosaur.. Try 80.. You may try lowering it to about 60 imo, maybe even 50...
 

ROOSKIE

Major Contributor
Joined
Feb 27, 2020
Messages
1,915
Likes
3,394
Location
Minneapolis
Room size is medium living room (12x18x8) using mostly for music but sometimes for movies too...

BMRs are crossed at 50hz to the subs.

Do you listen loudly?
I do regularly play louder and loud and even occasionally real loud. My room is 12x23x9t with openings as well, so similar but a bit larger overall.
In my opinion the BRM is going to be best crossed at 80hrz at anything above "louder".
The large cabinet size (for that woofer) does not control the driver as well as a smaller cabinet would. (Though it gives great extension)
In reality if the BMR was designed specifically for use with a sub and higher output the cabinet would be about 30% of that volume - or even smaller.
In my testing 80hrz is perfect in terms of mitigation of HD and likely IMD & Doppler.
Subjectively and off the ASR record that SB acoustics woofer is to died for in SQ. I love it. Stunning, stunning driver. That said below 80hrz the sub is going to be having such an easy time moving air.

I don't fully agree that essentially all subs sounds the same. Especially since I reccomend 80hrz for the BMR so the sub will still be working in a very important range.
Well designed 15's should have no issue.
 
Last edited:

nerdoldnerdith

Senior Member
Joined
Sep 10, 2020
Messages
495
Likes
690
Location
Chicago
I would recommend Power Sound Audio. Something like the V1512 or S1512. I have owned many many subs now including those from Rythmik, JTR, SVS, etc. What I have learned about subwoofer design over this time is that the most important criteria for subwoofer design are for the most part force factor and power handling. Everything good follows from there.

Power Sound Audio uses pro audio drivers that are designed according to the best principles of subwoofer design, and these drivers are hard to best unless you go with something boutique and expensive like Funk Audio. They are way better than home theater subwoofers for music and no worse than home theater subwoofers for home theater when used in a proper enclosure.
 
OP
birkbott

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
I would recommend Power Sound Audio. Something like the V1512 or S1512. I have owned many many subs now including those from Rythmik, JTR, SVS, etc. What I have learned about subwoofer design over this time is that the most important criteria for subwoofer design are for the most part force factor and power handling. Everything good follows from there.

Power Sound Audio uses pro audio drivers that are designed according to the best principles of subwoofer design, and these drivers are hard to best unless you go with something boutique and expensive like Funk Audio. They are way better than home theater subwoofers for music and no worse than home theater subwoofers for home theater when used in a proper enclosure.
I considered PSA, the S1512, I’ve heard they are great subs. Ultimately went with Rythmik for a few nit-picky reasons (lower power requirements, heavier enclosure, availability of 3rd party measurements, gloss finish). I’m all for using pro drivers for hi-fi but in this case I didn’t go that route. They remain on my list for the future though.
 
OP
birkbott

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
What about crossover slope? I’ve been using LR 48db which is as steep as it gets.
 

ROOSKIE

Major Contributor
Joined
Feb 27, 2020
Messages
1,915
Likes
3,394
Location
Minneapolis
What about crossover slope? I’ve been using LR 48db which is as steep as it gets.
I usually get better results with 24db.
48db sounds great in theory however in real room having overlap in the bass region is good and is really move sources to help even out room modes.
I use PEQ so the peaks are taken care of.
I have also had success with overlapping the subwoofer to monitor crossovers by 1/2 to 1 octave. That is a bit more advanced to get right but it can help fill in and even out both room modes and SBIR issues. Usually when I do this I use 24db slope on the mains and 48db on the subs as they are crossed higher with the overlap so I don't want them active much past a certain point.
 
OP
birkbott

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
I usually get better results with 24db.
48db sounds great in theory however in real room having overlap in the bass region is good and is really move sources to help even out room modes.
I use PEQ so the peaks are taken care of.
I have also had success with overlapping the subwoofer to monitor crossovers by 1/2 to 1 octave. That is a bit more advanced to get right but it can help fill in and even out both room modes and SBIR issues. Usually when I do this I use 24db slope on the mains and 48db on the subs as they are crossed higher with the overlap so I don't want them active much past a certain point.
Yeah that’s my concern only having one sub I don’t want to be able to localize it. I’ll play around with it. 24 on the mains and 48 on the sub sounds like an interesting idea.
 

ROOSKIE

Major Contributor
Joined
Feb 27, 2020
Messages
1,915
Likes
3,394
Location
Minneapolis
Yeah that’s my concern only having one sub I don’t want to be able to localize it. I’ll play around with it. 24 on the mains and 48 on the sub sounds like an interesting idea.
To be clear when I really need the 48db slope I am sometimes using a x-over of about 125-150hrz so that is why I kill it faster. I have many many use cases that I adjust for as I test stuff.

I don't know for sure where your sub is in relation to you (did you stick with near the front?)or if you went with the 80hrz choice or 50hrz as in your OP.

With 50hrz @24db there is zero chance of localization to the frequency itself. Maybe port noise or vibrations, deff not the audio itself. 50hrz is 22ft+ and instantly gets "bigger"(comes from multiple sources in the form of refection's) as it bounce off walls. Plus the sub is already down 6db or so at 50.

With 80hrz LR4 it is still really the same as above. The sub is already down 6db @80hrz and falling fast(in theory but the sub might have a rising response here that is common so maybe not exactly 6db) it is around 24db down by 160hrz which is right around where localization is considered typical. Very doubtful that would be audible output vs whatever the mains are playing. If the sub is behind you maybe. If in the front or near it is very doubtful, unless again it is port noises, mechanical noise or vibrations - including the wall or items in the room vibrating. 80hrz is 14ft and again within a fraction of time that 14ft wave is being reflected around and so many multiple 14ft waves are hitting your ears...very hard to localize in a typical sized room.(impossible?)

Obviously you can play around. You have REW and a decent mic to measure each change? I know you Dirac but that is not quite as friendly toward capturing various measures. (at least I don't believe it is, I don't use it. I use manual PEQ which I am certain is something worth trying if you ever get some time and feel up for it)
 
OP
birkbott

birkbott

Active Member
Joined
Oct 11, 2019
Messages
115
Likes
62
Y
To be clear when I really need the 48db slope I am sometimes using a x-over of about 125-150hrz so that is why I kill it faster. I have many many use cases that I adjust for as I test stuff.

I don't know for sure where your sub is in relation to you (did you stick with near the front?)or if you went with the 80hrz choice or 50hrz as in your OP.

With 50hrz @24db there is zero chance of localization to the frequency itself. Maybe port noise or vibrations, deff not the audio itself. 50hrz is 22ft+ and instantly gets "bigger"(comes from multiple sources in the form of refection's) as it bounce off walls. Plus the sub is already down 6db or so at 50.

With 80hrz LR4 it is still really the same as above. The sub is already down 6db @80hrz and falling fast(in theory but the sub might have a rising response here that is common so maybe not exactly 6db) it is around 24db down by 160hrz which is right around where localization is considered typical. Very doubtful that would be audible output vs whatever the mains are playing. If the sub is behind you maybe. If in the front or near it is very doubtful, unless again it is port noises, mechanical noise or vibrations - including the wall or items in the room vibrating. 80hrz is 14ft and again within a fraction of time that 14ft wave is being reflected around and so many multiple 14ft waves are hitting your ears...very hard to localize in a typical sized room.(impossible?)

Obviously you can play around. You have REW and a decent mic to measure each change? I know you Dirac but that is not quite as friendly toward capturing various measures. (at least I don't believe it is, I don't use it. I use manual PEQ which I am certain is something worth trying if you ever get some time and feel up for it)
Yeah the room is 12’ wide I have the speakers about 8’ apart against the right wall and the sub in the front left corner. I may move the sub closer to the left speaker depending on measurements. I do have REW and a UMIK so I’ll measure the next time I have the house to myself. The new sub comes Friday, will start with 80/24 and see how it goes.
 
Top Bottom