Can anyone hear the difference when you add REL subwoofers when playing two channel

Would any good card carrying audiophile introduce one of these high pass filters into the signal chain if they want to off load some of the heavy lifting of the amp? What I might end up doing if I can't find 2 used Vandy 2wqs (with X-over), is to mimic the Vandersteen method but without paying the Vandersteen prices. (New SUB 3 just too much unfortunately).

Thinking is to get the HSU x-over:
http://hsuresearch.com/products/high-pass-filter.html
And pair it with a Rythmik F12
http://www.rythmikaudio.com/F12.html

Could this sound as good as a SUB 3 or maybe even surpass it?

What are your thoughts?

Too much thinking again...naughty naughty!  Less talk More fun REL NOW

Unless you have a large room I would stay away from the lower end REL subs for a 2 channel music system. The S5's on down, I believe all use a downward facing passive radiator which helps the sub achieve lower frequencies and deliver a nice rich fat tone but it can also create definition issues in the low mids and can be . REL's also do not have any phase control, just a polarity switch. Phase control is very useful if you have two or more subs. I would also recommend using a very good crossover but most audiophiles have a very strong aversion to them even though a good crossover with time alignment capabilities can do amazing things for your soundstage.

As far as room placement any reputable sub manufacturer should have placement information on their websites including REL. I would also check out Soundoctor.com for highly detailed information about subwoofers and their placement.

My RELs were found on Ebay a year or so apart for 200 bucks each in excellent condition working perfectly. Lucky score I admit, (and a few years ago)...still...worth looking around as they show up from time to time, especially the Q108MKII.

I really like Rythmik's price to performance ratio. You can get a really substantial, musical sub woofer for right around 1k. I think you can get a REL that digs super deep, but would have to pay thousands more. REL looks terrific - furniture grade stuff right there.

To bstatmeister:

Sounds like you like Rythmik.  Their Servo system seems interesting.  The owner of Rythmik told me the REL's won't provide the kind of bass extension their subs can deliver.  Another speaker manufacturer said the REL T/9i's will be lucky to play down to 35 Hz.  I certain songs play a lower Hz levels, these will not be able to play those frequencies.

If size is a factor you should do the F12, otherwise why not plumb 10Hz territory with the F15 (although I think F12 can get close). These bad boys can even do high level connection like the REL, just doesn't terminate with the speak on connector. 

Dave_b2:

I wish I could send you a picture of my living room to show you how my system fits into the room.  There is only about 3 feet between the left and right walls (perpendicular to the front wall) and my long stereo cabinet.  If I would put two subs next to the towers, I would have to move my towers a little closer together (currently spaced 8 ft across) and put the subs between the towers and the outside walls.

I have also been talking to a highly regarded speaker manufacturer and he thinks the Rythmik subs to be far superior to the REL.  If the REL T/9i's are rated at 28 Hz -6 db, he said they would be lucky to play down to 35 Hz.  He said this is woofer territory not subwoofer territory.

If I do that, Rythmik makes their E15HP and a F12 Signature.  What size would you go with.

And the saga moves on!

Low level connection sucks.  No sub should be in a corner...ever!!  Even with mains (just outside or inside speaker position) facing out or perpendicular along plain of main speakers .  Sometimes near listener/ behind works but that’s more for HT.  I can hear subs if not integrated to the plain of the mains.  2 is ideal but one can do wonders as well.

OK, gotcha both.

Speakon’s are so well made for years I’ve dreamed of a replacement for the IEE female end of power cables. The majority of my PA snake, monitor, and Bass rig cabling is DIY Canare with Speakon terminations, dependable gear.


Dave, when we did our half baked sub comparison we eventually did over think the beautifully made Studio III. We relocated the sub from out of the corner and set it on its side then fed it processed equalization via low level RCAs from the DD Velodyne. The overwhelming consensus was that it dramatically improved its integration and presentation, demonstrating its weakness wasn’t so much a lack of amplifier power rather the lack of modern sub setup and technology. As I mentioned earlier despite the improvement its owner let it go.

Maybe he's not referring to the Speakon plug itself, but the efficacy of the REL "high level" input design. I'm a fan of the angled Speakon because, a. They keep the cables better sorted (whatever THAT means) and, 2. They're made in Liechtenstein. I terminate the speaker end of the Canare Star Quad cables I use for the subs with spades (bare wires? I'm not an ANIMAL), and pile the 
leads on the speaker posts (one for each negative terminal and two on each hot terminal for identical signals to each REL). The main speaker's amp end of the cables are high quality (ripened) bananas that fit the terminals perfectly. Remember, shrink wrap for cable finishing is your friend.

Referencing the HL amp connection.  Tracks amp output identical to mains.  Many use RCA OR XLR LL connections.  Never use speaker / sub crossovers on subwoofer...gah!  It’s slick, musical and can go wirelessly.  REL emphasis has always been on 2 channel audio and musical support, not sound effects.

R E L
Don't overthink it!
The Speakon connection makes a huge difference alone plus they are designed to augment music...not HT

i added a q150 to my revel f30s, which extend pretty low, but needed some more fullness and dynamism, esp. in the midbass region. i found the rel very easy to integrate and a significant improvement.

Larry, 
Speakon is simply another method of speaker or high level cable termination typically found in pro audio applications. REL uses a Speakon connection at the subwoofer end only.
Servo driver control is a monitoring technology that decreases distortion in long excursion drivers. 

Introducing any basic subwoofer/s into your room/system is far from impossible and should add a welcome dimension to the presentation. It can be challenging which is why many hobbyist and reviewers have had negative experiences over the years. The acceptance and ease of signal processed units by these same people has been game changer. 

JL Audio markets the basic E series and DSP equipped F series subwoofers which they're famous for. Their differences are substantial. 



lalitk,
["I picked out REL for bass quality and their seamless integration"]
I'm interested as to what and how you compared your final choice to?
The owner of an $8900. REL Studio III we compared sold his the very next week despite our efforts using four different methods of setup. 

"Can anyone hear the difference when you add REL subwoofers when playing two channel?"

Yes.
Best,
Jim Smith

@mzkmxcv &  @lalitkm,

I have heard a 10" SVS sealed at a friend's house paired with a pair of NHT's and with his Anthem room correct software, I was unable to detect the subwoofer.  I know this is what you want.  He set his sub perpendicular to his right front tower about 5 feet in front.  However, most audiophiles do not consider SVS to be an audiophile subwoofer.  I hear good things about JL, but I don't think I like how they work by taking over the woofers to produce bass extension.  I have heard great things about Rhythmik and their Servo technology sounds similar to REL's Speak On technology.  What I don't want is a pounding bass to drive me out of the room.  My primary focus is musicality, as I probably watch movies in 5.1 Dolby only about 30% to 40% of the time.  I respect your input.

@mzkmxcv,

So you actually have no real experience with any of the subs you criticize or endorse....should I pay heed to someone who peddles his opinions based on measurements posted on intranet or someone who actually have tried and tested the equipment....hmm take a wild guess 😉

@lalitk  
 

dimensionality, air, presence and texture.  

 You mean made up terms? 
 
REL sells a $1200 10” that is -6dB at 28Hz, that’s insanely laughable. 
 
If aesthetics/size isn’t an issue, a Rythmik FV15HP is the same price and a much better subwoofer. It has group delay below 1cycle, a pretty good spectral decay, and passes CEA2010 THD limits if restrained to 104dB from 16Hz and up. 
 
Here’s the frequency response of the REL T5, $600 and you can’t even get a neutral response, such a shame. 
 
Here’s an HSU sub as a comparison. 
 
Frequency response linearity isn’t everything, but I expected more. 

One Rel T9i absolutely rocks my friends 13’x14 room!  Bass that you can feel and hear as well.  Nice defined bass that adds a ton of dimensionality.

My brother picked up a pair of Sumiko S9’s for $1100 from Wally at Underwood HiFi and paired to the same Kef LS50 wireless as my friend with the Rel T9i and they are okay...  room dimensions, flooring material, and placement will play a huge role in how your Rel, or any sub for that matter, will sound.

When setting up the Rel, you should be able to tell just a slight difference in sound.  Fuller, more air and dimensionality, etc.  I can actually hear the difference a Rel makes to vocals, which seems strange to me, but I think there are many underlying deep bass notes that we don’t miss because we don’t know that they are even there, until they are.

I think you’d be happy with either a pair of T9i’s or Sumiko S9’s.  I usually prefer 2 subs over 1 since they seem to be easier to integrate in my experience.  But then again, that 1 Rel T9i absolutely rocks my friends smaller living room in a way I’ve never heard a home stereo sound.  Its quite engaging.

Most people have no idea how powerful 100 watts actually can be, and the 1000 watt or so subs that are around generally use a class d amp to get to that level and only a fraction of that power gets seen by the driver, so it's seemingly a marketing thing as the overall design is what counts more than the horsepower. Stick an Ampeg SVT bass amp (300 tube driven watts into 4 or 8 10" drivers) in a room with the loudest home audio rig you can find, and that bass amp will embarrass the home audio system all day because it actually can use all the power from an uncompressed signal. At full steam you'd have to leave the room. There is no non-pro speaker that wouldn't instantly blow from 1000 actual watts. Highly efficient speakers make low watt amps work beautifully (at least with well designed amps), and a 100 or so watt well designed sub will mate beautifully if set up properly.

"I also question why REL manufactures their subs with such low wattage? For example, their S3 delivers only 400 watts and their T/9i's deliver just 300 watts. When comparing them to subwoofers like JL, which deliver 750 watts to $1500 watts, maybe REL subwoofers are just too wimpy.,

Power is not what makes deep, convincing bass. A combination of construction and location do more than the gimmick of massive wattage specs.
 
Have you ever heard a quality 5 watt tube system at full steam? Close enough to concert level for most ears.

If you're not hearing the difference when the sub(s) are off, then they calibrated incorrectly. The overall sound quality would be immediately noticed, when turned off. 

IMO, even the finest speakers in a great room, will SUBJECTIVELY sound more convincing with properly adjusted subwoofers.

“If you want deeper bass, RELs are a poor choice.”

@mzkmxcv,

It’s not all about deeper bass in a two channel audio, does any of these rings a bell....dimensionality, air, presence and texture. 

Which REL sub have you tried in your system to form such poor opinion? If you did try one, how did you connect the sub?

If you want deeper bass, RELs are a poor choice. Without getting into the insanely expensive, Rythmik, HSU, PowerSoundAudio, and SVS give good/excellent musical performance and dig much deeper than REL.

When I listened to the S3, I got on my knees and put my ear next to the speaker and it was not pulsing out the beat. All it was doing was putting a steady humming sound. Hard to describe.

Something is wrong with the setup. The steady hum could be a grounding issue. Sounds like your dealer doesn't know what he is doing.

Are you going to be using this sub in a large or small room?

You should buy a track of just the 1812 Cannon and put on repeat

I have 2 "older" UK made RELs, a 10" Q108MKII at 100 watts, and a Q150e at 150 watts, and they integrate into my listening room extremely well...you do have to pay attention to level, crossover points, phase, and location, but even without a "room correction" gizmo they sound fabulous, and I don't miss a 20hz anything. I did drag my 92lb Mackie HRS (designed for recording rigs and not necessarily pro audio live work, although I have used it for a pro gig...once...) sub in from my recording room when I first bought the thing, and although it's a 19hz capable 500 a/b watts monster,  it didn't seem to add anything that I wasn't getting from my RELs. Sounded fine, but I guess I don't listen to pipe organs much. 

I believe it will only Throb with bass if the REL's low pass filter is "listening" for such frequencies. If the REL is set at 30Hz, but the Throb frequency is happenging at 40Hz, then the REL won't play it. That hum may well be the reverb/transient information and could be normal. Play music that for sure thumps at 28Hz then check again. Probably wouldn't want to get your ear right up to it. 

Audioman58:
Doesn't the SVS turn the towers in to boom boxes and throbbing bass?  Did you have the same problem I am having hearing difference when you add and subtract a REL subwoofers when 2 channel listening?  The dealer told me I am listening for the wrong thing, an added bass sound.

When I listened to the S3, I got on my knees and put my ear next to the speaker and it was not pulsing out the beat.  All it was doing was putting a steady humming sound.  Hard to describe.

See my post which is directly related:
https://forum.audiogon.com/discussions/kal-on-sub-integration-and-antimode

@larry5729  I'm not going to bother going to the REL site to check but I would be highly surprised (to put it mildly) if the T9/i puts out 300 "class A" watts.  

I have 2 rel. this is how you set up high level input:
make sure the yellow and the red are twisted together and going into the positive left on your amp and the black into negative left, and do the same on the right outputs. Put the crossover about sixteen clicks and the low level at about 10 clicks from zero. Play a track w repeating bass line. Lorde “tennis court” is a good one.Tune one sub at a time with the other sub off. First flip the phase button and whichever way sounds louder is probably the in phase for your setup. Work the crossover back toward zero until you like what you here. Work the bass level back to zero until the bass level matches the speakers but just kinda extends the bass response. Do the same on the other sub.  You’ll have bass that is on stereo and match’s and extends your speakers. Look for better soundstage and clearly better bass and midrange. Listen to sympathy for the devil, listen to the bass guitar, you can hear the guitar 🎸 not just the beat but the actual instrument, you can almost picture the strings being plucked. You can mentally picture where in the stage the bass player ( Bill Wyman?) is standing. Now your all set.

You can also run LFE input on the rel in conjunction w high level. If you have a surround processor w lfe out, this will go into the rel and should only come on with movies that have an lfe track.

MAKE SURE that your not running high level out into the REL and LFE out into the REL HIGH LEVEL INPUT at the same time. The sub out or lfe out on your amp needs to be input on the rel lfe input, not high level or you’d be defeating the purpose of true stereo bass extension. 

I hope this helps 
-ak

In my experience having dual subwoofers (left/right channel) has made significant impact on the sound in terms of bass extension, depth of soundstage, air between instruments, etc.  Having said that, it does take some time to get it right.  Things such as placement in the room with respect to your main speakers, phase, low-pass filter, and volume settings all factor in so they blend in nicely with your main speakers.  When all is said and done, you really shouldn’t know the subwoofers are there, beyond the apparent soundstage enhancements.  Before you even start configuring subwoofers in your setup, make sure you have optimal speaker alignment first as well as seating position (should be where you have smoothest/even bass response.  I don’t have the fancy RELs, but own a pair of Definitive Technology Supercube I subwoofers.  Bass response is 13-200Hz and clock in at 1500W (more power than I need).  I’m always a little skeptical about in-store demos as things are probably not fully optimized.  From my perspective, it’s all worth the journey for getting better sound.
Gorm 

The Sumiko dealer I mentioned before is Paragon Sight & Sound. Sumiko isn't making subs any longer so the prices were low due to them being discontinued. I believe the Sumiko designed subs are now being made by Sonus Faber with a big price increase.  

I have 2  Sumiko S.9 subs which share the same technology as the Rel Ti9. Sumiko owns Rel & they're remarkably similar in design, specs & sound.  Paired with my Maggie 1.7i, one unit made a big improvement. Adding a second unit was markedly better. I have both subs on a wall switched outlet, so I can turn them on & off simultaneously to instantly compare the Maggies with & without the extended low end. The difference is huge.  The name escapes me now but I bought them from a retailer advertising the Sumikos for sale here on audiogon. I pushed hard & was able to get them fir $650 each shipped. I think the dealer is in Michigan. I'll try to find the paperwork & post their name. I got them about 3 months ago.

To the OP, I thought the same exact thing when I demoed REL! For the life of me I couldn't hear a difference.. In fact, since the salesman insisted he could hear the difference, I took control of the subwoofer power switch and told him to tell me when it was on or off... And he got it wrong!  I do believe it can provide space, but I think it needs to be with the right speakers. Perhaps the speakers I was listening to were just phenomenal to begin with and covred that range. 

I am in the market for a woofer stereo pair. Right now I'm leaning toward Rhythmic F12s. SVS SB4000 also intrigues me.  The problem I have right now is spouse acceptance factor. I need to run cable to the woofers, but my amp is on a big mantle above the fireplace. That means the cables will have to come off the mantle at some point to connect to the amp, and will be an eyesore to the wife.  

I've looked into wireless options (i.e. rel longbow) but have heard there can be significant delay with some wireless systems.  Not sure what to do. 

ditto what dave said

I added a t9i to my modified khorn set up and it works great . I like how it hooks up to the speaker outputs this seems to keep it life like and blends in great with the main speakers. Rel makes larger subs as well if you want more power.

I couldn’t do without my REL....it adds dimensionality, air, presence and texture!

I have owned subwoofers from REL, JL Audio ,Monitor Audio 
and SVS , without question or even a second thought the Brand New SVS SB 3000, or ported is by far the best subwoofer under 
$1500 Period the sealed model for $1k delivered with a 45 day
audition ,they even pay the return if not happy. It is fantastic and has a great  app . For phone or tablet.
to control it and a bunch of adjustment parameters on the app
to go down to a solid 18 hz . I bought one thinking on getting another tuneful Powerfull Bass ,this sounds closer to their incredible SB16, this has a 13 inch driver ,a Solid 800watts 
with 2500 watt peaks ,and the most powerfull processor ever 
in a Sub, from Analog Devises. Just check it out .

I had a Rel Storm 3 in my system for many years. I now have 2 Sumiko S-10 (Rel S5 clone). Fantastic subs and add much more than just bass as mmeeks & others have said. Earlier Rels had even  lower power amps. The Storm 3 only had 150 watts. It still made a large difference. in my >5000 cu ft  room. The Sumiko's have 550 watts and I only have them set at 1/4 volume. I' like  the Sumiko subs They integrate very well and  make the speakers sound much bigger (Silverline Sonata) They have the same specs as the S5 Rel and have the same nutrick high level connectors. Only difference I could see between the Rel & Sumiko is the driver cone material. Sumiko was the Rel distributor for many years. They no longer are Rel distributors nor do the make subs anymore.

As jl above points out a simple way to hear what a subwoofer is doing is to simply turn it off.  

The REL method of speaker or high level connectivity was a solution to connect to receivers back in the day that lacked pre outputs. The assumption is using the same signal the speaker gets exceptional integration is guaranteed.   

REL describes their product as providing bass extension and is not a subwoofer. In my experience their products ability to integrate and their bass performance is mediocre. Regardless of my opinion, if its connectivity and presentation appeals to you that's all that should matter.

Higher end subwoofers such as JL Audio F series and Velodyne DD Plus offer automatic equalization, room optimization, higher quality enclosures, drivers, and methods of speaker cone control. While these companies make a handsome product the majority of their extra cost is internal, design, and development. They will integrate with any speaker and last through system changes for years to come. If there's punch on the recording they'll punch and the only thing that will get spoiled is you.         

Kind of agree with the dealer, but it also sounds like the subs aren’t well integrated. I mean, no, you should not be getting chest thumps, but well done, subs are GLORIOUS!! The effects he feels you should be getting you aren’t.

If you can’t hear a difference, it’s not worth money to you, then don’t buy it. :)
To integrate a sub well into most spaces you need a pair of bass traps and DSP EQ.

Without this, you are forced to cut corners, and often that means leaving the sub at too low a level to really do it’s thing. Turn it up, and the room modes wake up and destroy the sound.

The thing JL does better than almost any sub maker is the DSP/ room correction. This lets them contribute more, and go deeper.  Often a "Musical" sub means it can't go deep, so the dragons stay slumbering.

I've always read that when a sub is properly dialed in, you should not notice it, but when it is shut off, the difference is quite noticeable...many say it takes a few days of listening before you realize the difference the REL is making, not just in deep bass, but in overall sound...

And they are not sealed, they have downward passive radiators 

larry,

What are your room dimensions? Don’t be alarmed by low watts. The idea behind employing sub in a two channel setup is to strike weighted balance and full-range musicality not earth shattering bass as in typical home theater setup.