B-M-WOW! A tribute to the BMR, and my journey to them..

ryanosaur

ryanosaur

Audioholic Overlord
That's the conventional wisdom for mixing and matching subwoofers. There aren't any rules on whether a subwoofer should be sealed or ported as a result of what main speakers you're using.
The situation my acquaintance was describing is in fact similar to what my situation will be... but is not now. His logic made sense, though there was no science to back it up. He just wanted his roll-offs to match. *shrugs. Lets call it personal preference. I tried very hard to not make a 'factual' claim about it, hence why I called in the Big Guns to help clarify, and for me to learn some more! :)

For me, I'm using the X-13's extended (15hz) and the rolloff is all in infrasonic territory. As best I can tell having played with some test tones, my hearing stops at ~23Hz. I can't hear that rolloff, so for me, I'll be OK. Plus, my ears aren't on the top of their game. 'Gonna take a minute or three to get them trained back up!

I read that transmission lines and sealed boxes have a 12dB per octave roll off after the resonant frequency, while a vented box has a 24dB per octave roll off.
Now what Snake just brought up is a topic I'm really interested in exploring from a theoretical standpoint. If audible... would rolloffs of differing qualities within, say, 10Hz be heard/noticeable? What might a person hear as a sign something is wrong? Or would it not even be a thing? :)

In the case of Phil3s, I would look into a Geddes type subwoofer system where the main speakers are used full range. It would be a waste for those transmission line cabinets to go unused when they could certainly contribute to a very nice bass response.
And this!!! I want to learn more about. The logic behind Bass Managemment as I understand it seems to be largely a bandaid for science and the masses interacting. I would love to find a way to defeat the bass management and run my Phil-3s full range while still using my subs to augment LFE for everything else below 80Hz, and fully employ the extension from 25Hz down to 15Hz.
Maybe I'm being silly, and I can accept that if it makes sense. ;) But This is a question that has been tumbling around the inside the old brain for a few weeks now!
 
Steve81

Steve81

Audioholics Five-0
He just wanted his roll-offs to match. *shrugs. Lets call it personal preference. I tried very hard to not make a 'factual' claim about it, hence why I called in the Big Guns to help clarify, and for me to learn some more! :)
Possibly he was confused about which rolloffs needed to match? THX used to specify that their speakers should be sealed (12dB/octave rolloff),and high passed with a 12dB/octave filter, while the subwoofer on the other side was low passed with a 24dB/octave filter to create a smooth hand-off for bass management.
 
ryanosaur

ryanosaur

Audioholic Overlord
I agree with shadyJ about using Phi3 speakers full range. In fact, I'll go further to say one should listen to these speakers without any sub woofer before deciding on what sub woofer to buy. Listen for enough time to become fully aware of what they can do.

Properly designed transmission line bass is probably something that most people haven't heard, and it can take some time and listening before it sinks in. All this depends on what speakers and bass levels people are used to, and what they think they prefer. If someone is used to exaggerated or poorly damped bass, such as in most cars, this does take time.
When listening during my audition time, I was truly blown away by the capacity they showed! This was part of my thought process behind what I described to you in post#40. I wanted forever speakers. The BMRs are proving themselves highly capable. And I know the Phil 3s will not disappoint. My challenge is going to be in learning how to make it all fit together in a beautiful and seamless package for music (5-channel audio) and the ~20%video part of the equation. I'm up for it!!!

***Edit: Obviously, it's easy enough to kill everything else off, subs included, and listen to the Phil-3s in Stereo for any two-channel critical sessions. :cool:
 
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Steve81

Steve81

Audioholics Five-0
Now what Snake just brought up is a topic I'm really interested in exploring from a theoretical standpoint...What might a person hear as a sign something is wrong? Or would it not even be a thing? :)
Most commonly you'd see cancellations around the tuning point of the ported subs due to the associated phase shift.
 
ryanosaur

ryanosaur

Audioholic Overlord
Most commonly you'd see cancellations around the tuning point of the ported subs due to the associated phase shift.
Is there a point, in terms of range seperating the frequencies of the rolloffs, where they far enough apart for this to not happen?
10Hz might be too close, but 15? 20? :)
Thank you, Steve!
 
Matthew J Poes

Matthew J Poes

Audioholic Chief
Staff member
The situation my acquaintance was describing is in fact similar to what my situation will be... but is not now. His logic made sense, though there was no science to back it up. He just wanted his roll-offs to match. *shrugs. Lets call it personal preference. I tried very hard to not make a 'factual' claim about it, hence why I called in the Big Guns to help clarify, and for me to learn some more! :)

For me, I'm using the X-13's extended (15hz) and the rolloff is all in infrasonic territory. As best I can tell having played with some test tones, my hearing stops at ~23Hz. I can't hear that rolloff, so for me, I'll be OK. Plus, my ears aren't on the top of their game. 'Gonna take a minute or three to get them trained back up!


Now what Snake just brought up is a topic I'm really interested in exploring from a theoretical standpoint. If audible... would rolloffs of differing qualities within, say, 10Hz be heard/noticeable? What might a person hear as a sign something is wrong? Or would it not even be a thing? :)


And this!!! I want to learn more about. The logic behind Bass Managemment as I understand it seems to be largely a bandaid for science and the masses interacting. I would love to find a way to defeat the bass management and run my Phil-3s full range while still using my subs to augment LFE for everything else below 80Hz, and fully employ the extension from 25Hz down to 15Hz.
Maybe I'm being silly, and I can accept that if it makes sense. ;) But This is a question that has been tumbling around the inside the old brain for a few weeks now!
Well you are in luck my friend:
 
Steve81

Steve81

Audioholics Five-0
Is there a point, in terms of range seperating the frequencies of the rolloffs, where they far enough apart for this to not happen?
Depends. If the sealed sub rolled off early enough relative to the vented sub, and its output was negligible by the time the port got into the picture, there wouldn't be much interaction happening. Otherwise...
 
S

shadyJ

Speaker of the House
Staff member
And this!!! I want to learn more about. The logic behind Bass Managemment as I understand it seems to be largely a bandaid for science and the masses interacting. I would love to find a way to defeat the bass management and run my Phil-3s full range while still using my subs to augment LFE for everything else below 80Hz, and fully employ the extension from 25Hz down to 15Hz.
Well you are in luck my friend:
You are in luck, Matthew Poes understands Geddes' subwoofer system better than anyone aside from Earl Geddes himself, so he is the guy to ask if you have any questions.
 
lovinthehd

lovinthehd

Audioholic Jedi
And this!!! I want to learn more about. The logic behind Bass Managemment as I understand it seems to be largely a bandaid for science and the masses interacting. I would love to find a way to defeat the bass management and run my Phil-3s full range while still using my subs to augment LFE for everything else below 80Hz, and fully employ the extension from 25Hz down to 15Hz.
Maybe I'm being silly, and I can accept that if it makes sense. ;) But This is a question that has been tumbling around the inside the old brain for a few weeks now!
You wouldn't be defeating bass management for the scenario you describe, just using it differently. The subwoofer mode LFE+Main pretty much does what you want with speakers set to large and using the low pass on your sub at 80 or wherever. Not sure what you mean by augment or fully employ extension maybe. Remember LFE only exists in the .1 tracks of movies/multich music (and some of that music isn't really LFE per se).
 
ryanosaur

ryanosaur

Audioholic Overlord
My comment is most assuredly clumsy. ;) I’m planning a re-read of basic bass management related material now that I have more experience in the way of 1 month :) now with my subwoofers (and only a week with my speakers) under my belt. But I’m experimenting daily to hear how changes sound when I futz with various settings. Often times setting them back when I’m done. Today was phase day with the subs, for example, and I did notice a boost in the bass when I adjusted Sub1 somewhere between 90-180. And maybe I’ll realize that idea is off... ;)
 
KEW

KEW

Audioholic Overlord
I also told you the light was bright didn't I. I wanted to tape it but it has not bothered me enough yet.
I had a light that was too bright on a Presonus pro audio monitor. I didn't want to cover it with electrical tape because it would not look nice and I did want to see the status. I opened the case and put two coats of black Sharpie on the exposed surface of the plastic (inside the case) that carries the light to the outside of the case. I was very pleased with the result as it was easy to detect if the light was on, but it wasn't a dominating feature in my dimmed (but not dark) room.

Edit: Just read Slipperybidness comment about using black nail polish. that would work better if you reall want to dim it. For the light I was doing, the plastic surface on the inside had more surface area exposed than on the outside. You could easily leave a portion uncoated to determine how much light transmitted. If you want a truly low level, you could coat it all then press a knife into the nail polish to open up a very narrow slit of light (which would still show as a dim round "dot" outside).
 
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KEW

KEW

Audioholic Overlord
In the case of Phil3s, I would look into a Geddes type subwoofer system where the main speakers are used full range. It would be a waste for those transmission line cabinets to go unused when they could certainly contribute to a very nice bass response.
For bass for music, I have never heard better than the Phil3's by themselves! No, I wasn't listening to pipe organ pedal tones or electronica, just electric bass and drum kit. Of course so much depends on the room and speaker placement...
 
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ryanosaur

ryanosaur

Audioholic Overlord
A few more steps along the path:


Not gonna lie: this hurt my soul a little bit.

At least I didn’t miss the spot!

Voilà!



Sent from my iPhone using Tapatalk
 
ryanosaur

ryanosaur

Audioholic Overlord
*sigh...
I had to find an inexpensive solution for the horrible way I have the Mini-Phils set up... found a VideoSecu stand that was $40. And you know what you get for a $40 Stand (pair)... Two $5 dollar stands, packaging, branding, import fees...

I'll play with them tomorrow, see if I can rig up a stable base to keep them from tipping over when I put the Mini-Phils on them.

Cheers, all!
 
Kvn_Walker

Kvn_Walker

Audioholic Field Marshall
A few more steps along the path:


Not gonna lie: this hurt my soul a little bit.

At least I didn’t miss the spot!

Voilà!



Sent from my iPhone using Tapatalk
Ah, the things we do for love...
 

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