I finally added a second REL Sub

I really love my dual subs with my CW IVs. Congrats.

Oz

Can you tell us the crossover freq you chose, and how low is the volume setting?

I actually prefer the two higher quality subs (different brand) that replaced my swarm of cheapo subs.The crossovers are set approximately where the bass starts rolling off in the speakers so they blend perfectly.

Thanks for posting this, it adds more confirmation of the same. I recently returned to a dual stereo sub configuration myself.  Was not for added bass.  The sole purpose and hope was to recapture a more balanced sound stage and presentation.  I was not expecting an overall improvement in imaging and sound stage depth, and this returned as well.  I'll never go back to a single sub configuration, or will have no sub at all.  

Just went this direction, and am waiting for delivery of two Rythmik subs. I have a REL now and may sell it or see if I can either add it as a third or use in another room. 

Yes two subs is great for every system. Best upgrade I ever made. 
Something you should try is high passing them. I 100% sure you will get better sound, as in much better. Crossing them over higher (40hz-70hz, I use 60hz,). This is not a low pass but a crossover to the mains and it will take your system up another level. 
The subs simply outperform your speakers under 80hz. At 60hz the drivers in your main speakers start to fall off and struggle. This also will take a lot of vibration out of the main boxes abs let the mids do their thing. 
There are a few options from JL and bryston for active crossovers. Something like a mini dsp might be a cheap way to try it if your preamps does not support it and the JL-CR1 is too pricy.  
https://www.soundstageultra.com/index.php/equipment-menu/537-jl-audio-cr-1-active-subwoofer-crossove...

The Distributed Bass Array concept at the heart of the Swarm subwoofer system was developed well over 20 years ago. More than likely it was around while you were coming up. Or at any rate it has been known a very long time. The sad, puzzling, perplexing part is why something so powerful and beneficial is still flying under the radar. Even now, you have two, when it would be so much better to have four. No not four as big and powerful, but whatever four you can buy for the same money. So the secret is still not understood.  

Sad. Puzzling. Perplexing.

Oh well. Two at least is better than one.

Yes, Millercarbon, I started the hobby in earnest in the 1990s.  

It is sad and puzzling the these devices got such a bad rep that they have been held back, at least a bit.  For every a-phile who uses one, it seems there's more who cannot stand them. 

I think they are wonderful when executed right. 

Well done!  I don't have two subs yet, and don't have REL, but agree with setting frequency range and volume very low.  Just enough to augment the bottom octave, and not feature the subs.  I'm only occasionally aware my sub is on.

@millercarbon  So with a DBA, 4 REL x T5i would be better than 2 x REL T9i? 

they fill things out nicely.

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Subs are for HT, not high fidelty, 
I am using Seas W18E001's, dual each cabuinet for bass and is rock solid, tight, musical lows, down to 40hz. Just awesome. 
Sub in my room would sound like a  HT boom box. 

frequency range and volume very low. Just enough to augment the bottom octave, and not feature the subs. I'm only occasionally aware my sub is on.

~~~~~~~~~~~~~~~~~~
No matter how low you set the sub to isolate for voicing only the lows, still you are going to have that boom-boxy sound effect, Subs are for HT usage only. Not  meant for music. 
Dual W18's go to 40hz, but has a  full rick true musical bass reproduction. 
I do not need my bass to go down to 20hz, there is hardly any notes  in that range in my classical cd collection. 
Refer to Troel Gravensens notes on his  dual W18 Nextel  design for bass . 

No matter how low you set the sub to isolate for voicing only the lows, still you are going to have that boom-boxy sound effect, Subs are for HT usage only. Not meant for music.

Not getting any boom-boxy effect below 40hz....especially from a T-line. Boxy sound is typically in the 125-250hz range, and/or is a room effect.

@mozartfan, There is absolutely no boom box effect.  What's more, REL subs are (unless they are HT subs) specifically designed for music.  They are more appropriately sub bass systems.  It sounds like you haven't tried modern subwoofers.   Not trying to be edgy but this is just not my experience or what I think of when I think of modern subwoofers. 

"I run them so low on crossover and volume that the only thing you hear is sweeter more extended highs against a fuller picture down low.  They are simply not audible in their own right"  ....If i read this correctly your setup is wrong.If you watch the Rel user setup video its explained the sub should cross right under yoir speakers drop off point to make a seemless transition,not set all the way down as you descibe.I suggest trying it the right way and see what you have

I agree, such a novice approach. Seems like it has nothing to do with the speakers, just integrating the subs to the room a bit. CW has 15" woofer (34hz), and adding 2 10" woofers (28 hz) isn't that big of a deal if you're low on crossover and volume. Doesn't sound like there's much room gain with this approach. You could probably get the same low frequency with the CW using better placement in the room.

What's the point without using measurements to justify the setup (ie REW)? Please don't use the my ear is better excuse, because it isn't.

I'm sure you like and enjoy what you're hearing with the 2 subs, but how much better could it be? At least with measurements you can actually know for certain what the differences are (positive or negative).

Seems like much gets lost in translation.  I do follow the REL method--nearly to spec.  But, even REL recommends fine tuning. What I was saying is that I do the fine tuning by ear listing to actual tracks with actual instruments--i.e. isolated kick drum, isolated stand up bass, and so on.  Then, I also listen to a group setting of those same type of instruments--sometimes the same track where things get busier.  

I tried DSP, mics and software.  Helpful for sure, but I didn't feel it was necessary to get into the very sweetest spot of linking it all together.  Wh


I've owned the CWIVs for 6 months and have experimented with all sorts of placement options, so at this point I'm confident that I cannot get the same low frequency with the CWIV through different position.  Actually, they are not bass monger designs in the first place.  And further, if I try to position them differently I surely can "up" the bass, but that position is not ideal as other things suffer.  

There's more than one way to skin a cat I suppose.  I'm smoking some ribs today.  In nearly all circles, cooking ribs fast is nuts and not appropriate.  I would never do it. But, there are experts who do and there are experts who don't who have tasted fast cook ribs and applaud them.  

I guess I just haven't found measurements as a panacea.  I built a handful of tube amps and a pretty involved preamp design.  Testing was important and shouldn't be ignored.  But just because it tests near perfect doesn't mean (TO ME) that it sounds better.  

Tuning a guitar by ear in seconds took years to master.  I can do it and meet 440hz spec.  With all humility, I'm not saying my ear is as good as a machine.   I also enjoy it. 

Here's to enjoying the journey!

What I'm saying is that I (or you) could buy a couple of no name brand 8" subwoofers and do the exact same thing. There is nothing musical to how you have these set up in your room. You mention sub bass, sorry that starts at 20Hz, these subs only go down to 28Hz. These are HT subs, so by your own words are not musical. The volume is so low, where's the music?

I just don't see what you're doing is anything to cause someone to create a thread about. As I said before, any novice can do what you did, except you spent $3k (list price), that could have been done for $300.00.

Personally, I'm more interested in here's a before and after thread - show us something interesting. 

I’m using two Velodyne HGS-15s to supplement KEF Reference 1s below 80 Hz. LR output from an Ayre KX-5/20 preamp goes to a SMS-1 bass manager that provides acoustic room correction for the HGS-15s. The sound is superb, never aware of the individual speakers.

Now for complications: I have a third HGS-15 and three HGS-10s. It’s been suggested that I use LFE from a Bryson SP3 processor I use for surround (front LR through Ayre by-pass) to the third HGS-15. I could use a second SMS-1 in pass-through mode to the three HGS-15 as a distributed setup.

I had a passive balanced 80 Hz 24 db high-pass filter built to insert between the Ayre preamp and amp, but it seemed to remove just a bit of the sense of air, so I haven’t been using it.

Advice about the subs and/or high-pass would be appreciated.

Golfnutz, ?! 
Thanks for saying my thread is pointless. Yes, if going out and buying gear and setting it up as the mfr suggests is novice and not to your liking, the lions share of posts here are just that. 
I must be an idiot along with others and REL to do this when $300 would give me the same result!  Thank you!!! 

Dear @jbhiller  : @golfnutz and @james633 and @dbphd  are rigth and seems you have a misunderstood about the use of two self powered subs in a stereo home system sound reproduction. Btw, mozartfan is totally wrong on this particular issue

Please read this link:

https://forum.audiogon.com/discussions/do-you-think-you-need-a-subwoofer/post?postid=310058#310058

Obviously that you need to have true subwoofers that can goes below 20hz and maybe an external crossover that with some subs you could need it and with other manufacturer subs you just do not need it. Just in case:

http://old.bryston.com/products/other/10B-SUB.html


Btw, at your seat position two well integrated subs are enough, you don't need 4 subs and I repeat: at your seat position to listen stereo MUSIC not HT.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

@keelyofmb, REL doesn’t make it too easy to tell the exact settings in numerical terms. I’ll add up the hash marks and non adjustment clicks to get you a better answer. For now, they are set with the crossover at about 9 o’clock and volume slightly higher. 
I’m leaning towards even a lower crossover setting with similar volume. In either range they aren’t stepping on the speakers toes.  
I’m curious to try an active crossover. That does seem like more expense and work though. 

@rauliruegas ,  Always good to hear from you Raul.  I think I understand what you are saying. Specifically, you (and your thread) like to hear and see that users allow more overlap on the crossover between what the subwoofer puts out and what the loudspeaker puts out.  I appreciate that.  

I just don't prefer that sound (without using a dedicated external crossover) because I don't want the Class D amps in the subwoofers taking over too much.  I use a tube amp and unless I could cut the loudspeakers off higher with a dedicated crossover, like you suggest, I don't prefer that much overlap.  

Personally, I'm more interested in here's a before and after thread - show us something interesting.

@golfnutz I'm pretty sure no one cares what interests you. Are you a new member of the Thread Police?

Oz

'Pretty Sure", like Tracy Morgan 'Pretty Sure'?

Oz,  be careful buddy!  Your subs don't look set up with way some may want so they must sound terrible. HA!!!!

@james633 , You have exactly the right approach. All systems using subwoofer miss more than 1/2 the benefit by not using a high pass filter on the main speakers. It can be as simple as adding a series capacitor to the input of your amp. You just have to know the input impedance of the amplifier. f = 1/2piRC  or C = 1/2piRf.  R is in ohms and C is in Farads so you have to convert to micro and picofarads. Order the right cap from Digikey. They might cost you $10 at most. 

Next you can get either an analog or digital 2 way crossover and bypass whatever comes in the subwoofer. I like 12 dB/octave in analog crossovers. I use 48 dB/octave digital. 

For those in this thread who have tried one sub vs. two stereo sub, what did you gain by adding the second one? Was it worth double the cost?

I've been using 2 RELs in my main listening system for years and recently bought another Q150e to match the one I've had...moved my previous 2nd REL (a Q108MKII) to a video system in another room. Suffice to say that running them mono as I do works beautifully to cancel standing wave issues, and I run them at the obvious point where the mains drop off (around 58hz for my Heresy IIIs, determined with test tones and my ears). I think leaving the main speakers at their full range sounds best with no high pass filter necessary...the cost for all three RELs bought used was less than one new one generally (about 700 bucks for all three).

For those in this thread who have tried one sub vs. two stereo sub, what did you gain by adding the second one? Was it worth double the cost?

But it doesn't have to be double the cost. That's the thing. The benefits of multiple subs are so great you will get better bass from 4 no matter what your budget. You simply have to recalibrate your thinking by looking at it differently.

For example, say you have one really really powerful great $4k sub. Will two at $8k be twice as good? I don't know. But I do know for certain you can get four subs for $4k that will walk all over any one sub, be it the $4k one or even $8k, or whatever. Doesn't matter. That is how much better four are than one.

Dear @wolf_garcia : "" main speakers at their full range sounds best with no high pass filter necessary.. ""

I can’t argue of what you like but I want to comment that your speaker woofer handled/goes from 58-hz ( some reviews says that goes a little lower to 45hz. ) and crossover 850hz that it’s a very wide frequency range that ( even that you like it. ) develops high level of Intemodulation Distortions.

So, my point of view is that that speaker and its sound reproduction will performs at higher quality levels if we use a high-pass filter crossing at 80hz. In this way your speakers will handled a frequency range over 80hz and the levels of IMD will goes a lot lower and repeat in benefit of quality level performance. I can tell you that differences are " day and nigth ".

Up to you.

R.

Dear @millercarbon : Yes and 8 subs are better than 4. Several years ago Harman International made and proved in objective way, with measurements, the effect of several subs in a home system to listen stereo MUSIC ( not HT. ) and in those same white papers they were emphatic:

that two subwoofers is the minimum that works good in a stereo system at one seat position that's what normally what we need, at least me.

Then if an audiophile needs good low bass at several room position then it needs more subs to acghieve " flat " low bass frequency.

I have 2 units and performa great. It fulfills my targets that are way demanding on stereo sound reproduction quality levels.

R.

Really? It's up to me?...that's comforting...I know exactly where my Heresy IIIs drop off because I have listening skills and use a simple test CD and actual music to determine this, I don't care much about anybody else's opinions on the sound of my gear heap unless they've actually heard it, and have professional bi-wiring, bi-amping, and frequency manipulation chops going back to the stone age. Full range from the Heresy IIIs, such as it is, with the RELs gently adding lows to a degree I adjust from time to time (mostly simply level here and there, but rarely do they need it) after insuring phase and crossover settings are right adds none of the "intermodulation distortions" claimed, and the system sounds better than most others I've heard anywhere. Ain't no high pass resister getting near my stuff as long as I'm around. Get back you pesky resister...

Dear @wolf_garcia  :  This is what I posted:

""  I can’t argue of what you like...."""

You posted:

""  I don't care much about anybody else's opinions... """

good me neither.

""  are right adds none of the "intermodulation distortions....""

The main issue about is that even that you are not aware of it does not means does not exist.

Btw, I'm not against what you are listening this is up to you and I only posted a " comment " about.

That you don't like my comment is fine with me.

R.

The actual main issue is that you're assuming intermodulation distortions exist where they do not. I liked your comment just fine...need a hug?