Question about subwoofer: pair or 1 really good one?

Joey_V

So I have narrowed down my sub choice to JL audio. Why? Because of the outboard crossover JL Audio CR1 and the DARO took optimizer which appears to be much more comprehensive than on the Rel, even the No25.

So the question is this:
If I do not have position restrictions meaning I don’t have a TV in the middle and it is not a living room, can I get away with an easier to set up single JL audio sub in the middle of the front stage or better to go with dual lesser subs?

JL Gotham v2

Or

Dual JL F113v2

My worry with 2 subs is having to run DARO twice

F1nut

Get one, try it out. Then, if you feel it is not enough get a second one.

Joey_V

F1nut wrote: »

Get one, try it out. Then, if you feel it is not enough get a second one.

Tough to do if Gotham is the one sub.

rooftop59

Get the installer to come run room sweeps and see if you have any nasty nodes that the single sub/eq can't handle. With that kind of calibration and freedom to put the sub anywhere in the room, I can't see the one not being able to do the job unless you have a REALLY bad room...

delkal

Humans are tuned to focus on the exact direction and placement of mid range and up frequencies (and we are very good at it). But below 40-50 Hz you can't tell if a sound is right in front of you, to the side, even in back (unless you have a super golden ear or are a braggart). Low base frequencies are non directional.

Try your one sub in a "sub optimal" position first. I doubt you will notice a difference.

One big problem with two subs is with the longer base wavelengths it is difficult to avoid phase cancellations. These effects get worse the lower the frequency. You will probably find with two subs if you play a pure low tone and walk around the room you will find nodes where the sound is much quieter or louder. You can even hear these with just one sub. But with two you will find it is even worse.

voltz

Joey_V wrote: »

So I have narrowed down my sub choice to JL audio. Why? Because of the outboard crossover JL Audio CR1 and the DARO took optimizer which appears to be much more comprehensive than on the Rel, even the No25.

So the question is this:
If I do not have position restrictions meaning I don’t have a TV in the middle and it is not a living room, can I get away with an easier to set up single JL audio sub in the middle of the front stage or better to go with dual lesser subs?

JL Gotham v2

Or

Dual JL F113v2

My worry with 2 subs is having to run DARO twice

ahh come on bat man you can do better then that! Joey I can do a triangler and find you Have fun joey ...I have a special 8 inch sub I got from a special (omega person)

and it can make bookies that hit deep and filling the blanks that I never like it go...it was made for my full range Omega speaker by the owner an then he stop making them it was his one and and only Version of it??? but it sings like heaven and really add's to must bookies and I going to have to talk to him about why he never made it a option for his systems again and I think I own the one & only original... LOL

Joey_V

So here is my main issue...

I realized I need a cross over for the subs, hence the JL Audio CR1.
It can apply a high pass filter to the mains and cut it off for a gentle slope in of the subs via low pass (unless I got that backwards...).

Via a single gotham in the middle of the front wall, I can place the sub right in the middle, avoid using room gain (why would you need room gain with a gotham??).... this can avoid the potential pitfall of having two subs adding to each other despite room correction as it seems I cannot room correct both Fathoms at the same time (one gets corrected via DARO then the other gets corrected via DARO).

Not only that, but DARO does not account for mains and the FR in the room. That's where the CR1 comes in as it can allow me to cut the mains off where the subs get room corrected seeing as how I cannot room correct the mains by itself.

2 subs sound like a good idea in terms of smoothening the room response, but I don't see how 1 sub like a Gotham cannot be room corrected to provide optimum bass response at the listening position.

Is it that 1 sub might sound bad at other listening positions whereas 2 would sound more "even"?

That's what I don't understand.

afterburnt

Buy these since I didn't https://www.audiogon.com/listings/lis9dhj5-monitor-audio-silver-w12-subwoofer-discontinued-5g-gloss-white-new-5-yr-warranty-subwoofers

voltz

Joey_V wrote: »

So here is my main issue...

I realized I need a cross over for the subs, hence the JL Audio CR1.
It can apply a high pass filter to the mains and cut it off for a gentle slope in of the subs via low pass (unless I got that backwards...).

Via a single gotham in the middle of the front wall, I can place the sub right in the middle, avoid using room gain (why would you need room gain with a gotham??).... this can avoid the potential pitfall of having two subs adding to each other despite room correction as it seems I cannot room correct both Fathoms at the same time (one gets corrected via DARO then the other gets corrected via DARO).

Not only that, but DARO does not account for mains and the FR in the room. That's where the CR1 comes in as it can allow me to cut the mains off where the subs get room corrected seeing as how I cannot room correct the mains by itself.

2 subs sound like a good idea in terms of smoothening the room response, but I don't see how 1 sub like a Gotham cannot be room corrected to provide optimum bass response at the listening position.

Is it that 1 sub might sound bad at other listening positions whereas 2 would sound more "even"?

That's what I don't understand.

do you know how much hair I just loss? but I get your Question but it is over my head Brother!

This audio game can be cruel! keep us posted Brother! I gonna hang it there as long as I can!

delkal

Joey_V wrote: »

2 subs sound like a good idea in terms of smoothening the room response, but I don't see how 1 sub like a Gotham cannot be room corrected to provide optimum bass response at the listening position.

Is it that 1 sub might sound bad at other listening positions whereas 2 would sound more "even"?

That's what I don't understand.

Two subs will not smoothen your room response. It will totally wreck it with phase cancellations and harmonics cancelling or increasing the tones at the multiple nodes you will have everywhere in the room. Depending where you are sitting you will hear major differences moving a foot or two one way or another.

It is hard enough getting one sub tuned to a room and with some room sizes it is close to impossible at certain frequencies. Play a 30 then 40 then 50 hz tone with just one sub........then walk around the room. You will undoubtedly hear the tone getting much quieter or louder wherever you go. Maybe even when you stand up or sit down. And that will be just the phase cancellations from the reflextions your room does on its own. It will only be worse with 2 signals going.

No one uses two subs. Its unneeded and worse than one. At 50 hz the wavelength of the sound is about 20 feet (that is why humans can't hear low tones directionally). So putting it simply if you are sitting ANYWHERE within 20 feet of a sub you can't tell where the sound is coming from.

F1nut

No one, eh?

Conradicles

JL in the middle.

delkal

F1nut wrote: »

No one, eh?

I am impressed with your living room. It is much nicer than mine.

How much did you pay a professional to custom design and sound treat your room to avoid the destructive interference?

Emlyn

For two channel, another option of course is no subwoofer at all. If the main speakers are ideally set up and producing full range sound in the room already a subwoofer can only mess up their performance or be very difficult to get dialed in correctly. That gets even more difficult with two. Introducing DSP can also detract from the sound quality in a dedicated two channel system. The room construction and materials also play a very big role.

For home theater, I recommend two subwoofers, but that's a different story.

F1nut

That's not my living room, it's the shack out back.

joecoulson

One good sub over two lesser subs IMO

SCompRacer

delkal wrote: »

No one uses two subs.

This is an absolutely false absolute.

delkal

Notice the room looks to be very large and the multiple subs look to be well over 22 feet from the back wall. This will lessen the interference from trying to play a 22 ft long 50 Hz tone but still not eliminate it from the sides. Also notice there are custom sound treatments (which undoubtedly cost more than my whole system including the things I have in my closet) all over the room. They are not there for the tweeters.

I am sure their system sounds awesome. But for mere mortals with an average sized room.............stick to one GOOD sub.

afterburnt

delkal

afterburnt wrote: »

Is that you setting up your system or just another random pic off of the net showing someone with multiple subs. How does your system sound? Is six subs the magic number? Better than one? Or three?

I kind of said all I want to for this thread............but would like to know.

afterburnt

That's surveillance footage of my trying to "borrow" a sub or two.

tratliff

This is my latest set up. Two McIntosh 601’s running Legacy Focus S/E’s full range and a REL Carbon Limited in each corner. The RELs are connected to the amps via the high-level inputs. Each amp and sub has a dedicated 20 amp circuit and an additional 20 amp circuit for the source components. 5 total.

I have not been able spend a lot of time with it since setting it up. But have about 8 hours total listening time. From my observations the mids, highs and stage opened up significantly. And the depth/impact is something I have been missing for years.

Joey I think you will be surprised how this might change your system. I tried a single REL S5 for a couple of weeks before placing my order and while waiting for delivery. The difference between that single and the current pair was a night and day difference.

I am still working on the crossover and level settings but find both to be lower than I originally thought.

Good luck in what you decide.

Joey_V

Rels with hi level input I can see two subs. As it takes information from each main.

But if the input is low level, then I don’t see the reason for dual subs other than placement

ZLTFUL

In a perfect scenario, neither 1 nor 2 subs is ideal.

4 subs placed at the mid point of each wall is the ideal configuration for minimizing room modes, cancellations, peaks, nulls and generally **** bass.

One sub can be placed perfectly to get optimum bass response at the prime listening location. Move a foot in any direction and you will notice a severe drop off in bass.

If you have a single listening position, do 1 really great sub (The Gotham) and sub-crawl to find the ideal location for it.

If you have multiple listening positions, then 2 subs will help smooth the response across those multiple positions. But it also suffers from that placement having to be perfect thing as well.

I will be showing off a pair of DIY subs most likely at LSAF and will happily demonstrate how 2 subs can improve your experience dramatically.

rpf65

Your asking one great sub or two very good subs, the answer is two very good subs.

Little harder to dial in two subs, than it is one, but if you take the time, your bass response will be better over all.

Reason is your simply playing the odds.

Sound is kind of funny, if you think about it. See a null on any graph, and there will be a center point across 6 or 8 individual freqs. Maybe there is a 6 dB drop, centered on 40 Hz. At 36 and 43 Hz, it may be 3 dB. So it’s actually more than one wave length your hearing that drop off.

Adding a second sub, creates a second point of origin that generates that same freq range that you aren’t hearing as clearly. Chances are that the second sub will help boost that little dead area, because the waves are bouncing around the room a little different.

That’s the idea of using a second sub.

Read somewhere when I was trying to understand this stuff a little more, that the best number of subs in the vast majority of rooms is 4 placed in each corner. Any more, and the improvement is minimal. Your chasing that 1/100 of 1 percent.

This was a more HT related application, in that multiple, fixed seating positions were involved, but I really don’t think the low freq sound waves really cared. When it was a one or two sub comparison, the overall low freq response also improved. There were still nulls and voids, just not as dramatic as with one sub.

honestaquarian

https://forum.polkaudio.com/discussion/177244/pros-and-cons-of-multiple-subwoofers/p1

WLDock

The best advise anyone can give regarding the acoustics of bass in a small room is to really get educated on the subject before dropping $9000 - $16,000 on one or two subs. I think the reason many audiophiles don't like subs is because some rooms make it really hard to get things right. Following the advice of those that spend their life researching the subject is the only way to get the value out of such expensive endeavors.

Nevertheless, One really good sub can be tuned to sound pretty darn good for one seat. Two subs can work just as well but requires more tuning. Many times they are both placed upfront either inside or outside of the main speakers to make things look pretty. However, that might not be the best location.


Simply moving one sub to the opposite wall corner can make a huge differnce in some rooms. but many audiophile types are not willing to try it.


Further more, only a limited number of audiophile types are actually willing to use subs in their dedicated music rooms. Still, even fewer seems to be taking advantage of all of the work done by the engineers Geddes, Toole, Welti, etc. on multiple subs.



The SWARM or DERBRA four sub system.
[http://www.audiokinesis.com/the-swarm-subwoofer-system-1.html


http://jamesromeyn.com/old-pages/home-audio-gear/dsa-1-0-distributed-subwoofer-array-5-pieces-4k-usd/


FEEDBACK AND REVIEWS
http://www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/
https://forum.audiogon.com/discussions/anyone-else-using-an-audio-kinesis-swarm-or-debra-distributed-bass-arra
https://www.monoandstereo.com/2015/11/audiokinesis-swarm-subwoofer-system.html
https://www.whatsbestforum.com/threads/audiokinesis-swarm.20760/
https://www.audiocircle.com/index.php?topic=132434.0


I guess with everything( One sub, two subs, four subs, room correction, passive bass traps, active bass traps, etc, etc, etc......) there still requires experimentation, tuning, etc. to get to the main goal.

There are even ideas like the Double Bass Array to deal with room modes. https://en.wikipedia.org/wiki/Double_bass_array
https://www.avsforum.com/forum/155-diy-speakers-subs/837744-double-bass-array-dba-modern-bass-concept.html
http://redspade-audio.blogspot.com/2012/04/double-bass-array-dba-bass-integration.html
https://www.whatsbestforum.com/threads/comparison-of-double-bass-array-to-sound-field-management-overview.3320/
https://www.whatsbestforum.com/threads/comparison-of-double-bass-array-to-sound-field-management-the-meaty-part.3502/


This takes us 360 degrees back to the question, One Gotham or two Fathoms? Seeing that this sounds like an ultimate subwoofer integration for a dedicated music room, no one has talked about height integration or vertical modal coupling. Hence, the vertical stack.

The SoundDoctor wrote:

Now imagine you had a pair of f112’s. You could put them in the corners, 29% down the long wall as Art Noxon suggests or where the crawl-around test tells you to put them and so on. But notice in every one of these instances they are on the floor! You have not taken advantage of the height placement which changes the vertical modal coupling to the room! This is the magic of the f212 and g213; not that they are “just” a pair of f112’s or f113’s, but that the inherent design means the lower driver being near the floor will couple the lower frequencies (LFE noises in movies: 22–35 Hertz) better to the room, while the higher driver (at approximately 29% of the room height) couples the higher bass music frequencies (35–70 Hertz) tighter to your body. This is where the coupling ability of these subwoofers across a wide band of frequencies shows its magic! And if you own two single subwoofers, such as the f110, the f112 or the f113, you can do a coherent test yourself to determine the perfect modal room coupling for your particular setup. It is work but it is easy. Go to a home improvement store (Lowes, Home Depot, etc) and get four 8-inch cube cement blocks they are about a dollar. Now once you have found the best lateral placement for your room by doing the crawl-around test, you can experiment with vertical mode coupling by raising the subwoofer 8 inches at a time and learning the result. You may find that for your room and the type of program material that you mostly play, that this last step in fine tuning really makes your system perfect. Notice that there are some manufacturers such as Acoustic Sciences who make subwoofer stands; you should have at least 8-inches in order to make a difference in vertical modal coupling.

While anyone would love to have a one or two REL or JL Audio subs. Two or four of the double driver Rythmik F25 can be had for $3200 - $6400! or a little more to have a piano, automotive finish done by SALK who will do what ever you want for a fee. http://www.salksound.com/model.php?model=Rythmik+F25+Subwoofer
Salk Piano Black finish on SoundScape 8:


Then, use a DIRAC, Trinnov, DSPeaker Anti-Mode, etc for room correction.
https://hometheaterreview.com/room-correction-revisited/

So, much to consider...the room, the room, the room.....
http://www.acousticfrontiers.com/room-acoustic-design-insights-five-steps-to-amazing-bass/
https://www.psaudio.com/article/a-dedicated-listening-room/
https://www.acousticfields.com/ode-to-the-dedicated-listening-room/
https://www.acousticfields.com/get-good-bass-in-small-rooms/
http://arqen.com/bass-traps-101/placement-guide/

https://hometheaterhifi.com/technical/technical-reviews/an-interview-with-todd-welti-and-kevin-voecks/
http://seriousaudioblog.blogspot.com/2012/05/two-great-articles-on-multiple.html
https://jlaudio.zendesk.com/hc/en-us/articles/205061040-Adding-a-Home-Audio-Subwoofer


Also, don't rule out paying for the services of a subwoofer guro like Mark Seaton to setup your room for you. Maybe four of his JS-12 subs, or Submersives? At least talk to him about your goals with the JL's and see what he has to say. The guy is helpful on forums.
https://seatonsound.net/product-category/products/
https://www.avsforum.com/forum/113-subwoofers-bass-transducers/1633729-six-6-seaton-submersive-install-exceptional-service-mark-seaton.html

joecoulson

Wow. What a great stack of info!!

WLDock

Post from another fellow in the same boat as Joey, looking for great subs for a music system.
https://www.whatsbestforum.com/threads/subwoofers-compared.25334/

Mark Seaton wrote:

Thank you for including our F18 subwoofer in your list of many capable subwoofers. I suspect your availability information was from some months ago and closer to when you purchased your Funk subwoofer. Since about the first of this year, we have been able to finally keep the F18 in stock or within a 3 week lead time. We had units in stock prior to Axpona and are momentarily back to a 2-3 week lead for F18+ units (with slave units in stock). At long last we finally have information and ordering available on our website for our subwoofers, and the speakers will be visible by the weekend. Among the subwoofers already live is a newer model, the compact JS-12, which should be of interest for those looking for a more compact package, especially where multiple units are planned. The JS-12 has the same extended frequency response of our F18 & SubMersive which couple into most rooms delivering 8-12Hz in-room response.

What isn't yet posted is another 12" subwoofer using the similar enclosure to the JS-12, but instead using our ultra-low distortion, custom woofer from Acoustic Elegance we developed for and use in our Catalyst 12C loudspeaker. It has a little less maximum output, but will add the ability to drive 1 additional slave unit with the same very extended frequency response. Some have heard the bass produced by our Catalyst 12C speakers run in their full range DSP mode, and that is precisely what prompted the development of this subwoofer option.

While I agree that external electronics like the Trinnov, DSpeaker, MiniDsp, DEQX, etc all offer more flexibility and centralized control than we can offer in a subwoofer plate amplifier, in all of our subwoofers I have included precise crossover/low pass control with settings as low as 30Hz, and an "LF EQ" knob which provides a useful tilt/shelving of the lowest frequencies to best fit the preferred balance each user prefers in their room.

Seaton Submersives

WLDock

Having said all that,

joecoulson wrote: »

Wow. What a great stack of info!!

Yeah, there's a reason many spend so much time talking about subwoofers.

Still, when one gets to Joey's level models like Gotham, Fathom, Rel No. 25, G1 Mark II, etc. get the hi end heavy hitters in that rare club that few can afford to be in. I'm sure anyone that loves music or movies would be happy with a single Gotham. However, what if two or four lesser subs can offer the magic for less?

I have no idea what its like to have those decisions of wanting the performance and the prestige. My 2016.5 Mazda CX-5 is about the same value as a new Gotham!

I say set your goals first then move forward with the equipment one can afford to get there. The Mighty 1 vs. Very capable 2 question really can't be truly answered unless its experienced in one's own room.

delkal

Here are some online tone generators that can be use full to demonstrate the effect nodes and room outlay can have at lower frequencies. Play it for yourself at different frequencies and move around the room or in some extreme cases just move your head from side to side. You will probably hear as you move around the tone gets louder and quieter like someone is adjusting the volume everywhere you go. Depending on your room (and lack of room treatments) don't be surprised that at certain frequencies you will find a note where the sound going from very loud to almost can't hear it. It can be frustrating but this might help you place your sub(s).

onlinetonegenerator.com/

https://szynalski.com/tone-generator/


One word of warning when playing pure tones.......At the frequency extremes you will not hear anything. But that doesn't mean your amp is not sending a signal to your speakers. You have a tendency to turn it up till you hear something (even if you can't). You can fry speakers and amps this way. Also depending on frequency you will change the impedance of your speakers. An 8 ohm speaker can be MUCH lower at certain frequencies

So only play at low to mid levels.