KEF-LS50 with REL T-Zero? Anyone?

just wondering if that extra bit of low end the Zero will provide will compliment the LS50

You'll need more than an extra bit of low end to fix the missing bass on the LS50s.

Definitely use a sub with the ls50s in any room. I would only use ls50s for serious listening in small to moderate size rooms. They are small and as a result have limitations but they do what they do very well. Adding and properly integrating a sub fills in whats missing and delivers a complete and more satisfying experience overall. I use a small but robust 8" sub with my ls50s in a small 12X12 room (space limitations in there for me as well) and the results are spectacular, competitive with most any full range system at any price I would say.

Thank you Kenjet for your comments.  I almost didn't recognize the response came from you since the heading was missing your characteristic and pretentious "MUST READ" announcement.  Yes, I am aware of the bass limitations of the LS50. This is a small streaming system in a guest room.  I have no illusions of it being anything more than pleasant sounding quasi high end lifestyle system.  Once set up I may find that I am happy with it as it is but I am curious about learning from the experiences of others who may have used the LS50 with small subs like the T-zero.

Randyhat, get the speakers all set-up using the dsp.  I highly doubt that you’ll feel the need for any sub with the wireless LS50’s.  They had better bass in my room than the passives and a REL T9i.

They are definitely waaaay more than lifestyle speakers too!  I think you’ll be pleasantly surprised.  Do break them in for 200 hours though.  They will sound bright out of the box.  Don’t worry.  They’ll relax.

I have a friend with LS50W and Rel T9i, and my brother has LS50W and 2 Sumiko S9’s.  The main benefit with a sub is that you can cross the speakers over at 80hz, turn them up to 100 on the volume and rock the entire block for 3 hours straight and the system handles it.  I have noticed the sound starts compressing a bit after the 65-70 mark on the volume indicator.

Also, Sumiko is selling the S.0 for $250 each, and I believe they are the same as the Rel T zero.

Again though, listen to them before deciding.  They have surprisingly good bass.

If you are buying them new, you’re $300 would be better spent on an extended warranty covering the electronics part of the speaker for 3 or more years.  They feel a little finicky and they are only covered for 1 year through kef. 

I have the LS50 passive, not the wireless active version. As I stated in my original post I am powering the speakers with an Audio Research 100.2 solid state amp. (100wpc). Since my original post I have now received the LS50s and have them setup in the room. I am very pleased with the bass performance. Because of space limitations I do have to place them on a credenza and am unable to move them more than a foot from behind the back wall. At that distance KEF recommends inserting the partial (sleeve) plug into the port. This reduces the bass and in the process may be clearing up the midrange a bit...still too early to tell. Because of the fuller bass I like the sound better without the plugs....even a foot from the wall. My thought with a small sub is that I could play the LS50s with the partial plugs to clear up the midrange and have the sub extend the bottom end.

Also I am curious about the REL T-Zero itself compared to the T-5i in the same installation.  I wonder if the T-zero would be enough and if I really wanted to add bass weight over and above the LS-50 whether I should move up to the T5i.

But as you have suggested, I need to listen longer and wait for the speakers to break in. Thank you again for your observations and recommendations.

@randyhat, You can live with the KEF-LS50's as they are and will not a problem however I believe you will like even more the addition of a subwoofer.
Unless I missed the information in a post above, I would like to know the dimensions of the room.
The T-Zero and T5i are excellent choices, depending on your room size.
As already stated above Sumiko has discontinued some of their subs and The Music Room is running a nice sale on them. These subs are very comparable to the REL's.

Don’t know how I missed the passives part of that post...

T-Zero are nice and capable desk top subs down to 35 Hz. I run them with a PW AMP that uses the ARC room eq system. Removes the lowest bass from the monitors and as you say cleans up mid-bass. Indeed very good results. LS50/50W has in my opinion loud but non-interesting low bass information (as most small monitors). For a room system I would still say the PW AMP is excellent but you may need to step up to T5i subs (always at least use two). MartinLogan sells the same amp. Also the pre "Unison" with ARC if you like to use your own amp.

b_limo

Your advice about about setting up the LS50W actually turns out to be very relevant.  Since my first post I have received the LS50 and have been listening to them for a few days.  I realized after hearing them that if I really wanted more bass I would probably need something more than the T-Zero so I got the T5i.  It sounds good but I have heard so much about the LS 50w that I am going to audition a pair of those.  They should be here tomorrow.  I bought them from the same place I bought the LS590 and they agreed to let me return whichever one I decide not to keep.  Looking forward to a head to head comparison.

I have the T-Zero, it's good but really better to use with a desktop computer system.
I know you would be much happier with the T5i.
Please use my learning curve, and don't repeat my error, get the T5i or larger. My larger subwoofer arrives today ;-)

I agree lak, even the T5i is marginal in terms of the impact it has on the system.  Space and finances limit the degree to which I want to enhance this second system in a casita.  I am beginning to think that unless I can get a proper sub (T7i or above) I might just be as well off leaving the sub out of the system....particularly if the LS50W has improved bass performance and ends up being the keeper.  I have always had some form of a subwoofer in my system for the past 25 years.  I started with passive subs, them moved up to a larger REL (Storm).  I now have Vandersteen Quatros with the built-in subs in my main system.

Thank you for your advice.

I use a Klipsch sw308 sub with my ls50s and this is a very good pairing, if you can still find one.

The sw308 has 8" main driver and two 8" passive radiators and delivers a lot of detailed bass from a relatively small package.   Results are top notch.

I’ve debating adding an external active crossover but this sub meshes so well with the ls50s in my 12X12 room that I have happily opted to just keep things simple.

Save some bucks and try one of the Q108MKII RELs for sale on eBay...I own one of these (along with a similar vintage Q150e that also is a great sub) and they're amazing, and for around 200 bucks for a good used one you can't go wrong.

I've been listening to the KEF LS50Ws for about a day now....with and without the REL T5i.  They are pretty amazing.  Very similar to the LS50 but tunable to my room.  Something about those built in powerful amps that seems to focus and allow the speaker to project a rock solid image and soundstage.  A nice incremental upgrade from the very fine LS50 but not a "night and day" difference.  I'm still feeling my way through the KEF control app, experimenting with various settings to try to find the right mix for my room.  The basic settings seem to get you most of the way there while the "expert" settings offer a bit more refinement.  Adding the REL T5i to the equation complicates matters a bit.  I've used a REL sub in my main system for almost 20 years and have always used their recommended speaker level connection.  With the LS50W this is not an option but I am able to run an RCA cable between the KEF and the REL. I'm a little confused about how to combine the control settings on the REL with the settings in the KEF app.  KEF seems to recommend setting everything on the sub to max volume and highest crossover and make the adjustments in the KEF app.  Is this best?...or does it make a difference.  The KEF app has the option of using a "high pass" mode...or not.  Using the app to make subwoofer adjustments is like using a remote and much easier than getting up to make the trial and error adjustments on the sub itself.  Anyone with advice or experiencing setting up a REL with the LS50W?  I would appreciate your input.

I just looked up the T5i and I don't see why it can't be set up like any other REL even using the low level input...I'd simply set the REL at wherever the KEF's low (without DSP) rolloff seems to be and set the level on the REL which I assume will follow the KEF signal level. It then doesn't need a "high pass" signal from the KEFs as it does it on its own.

@randyhat - I am in a similar situation trying to get the best out of REL T9i and LS50W. Use KEF app/ REL recommended Settings. The main concern is I do not want to duplicate low frequencies on both REL Sub and LS50 W. I wish if either REL or KEF sheds some light on what controls to use these devices. It is indeed pretty confusing. Right now I have turned Hi Low knob to 15 turns at 10 o clock position and Cross over at 21 turns close to 75Hz? on REL and use High Pass Mode on KEF app set at 75Hz. Gain on KEF app at +2db with phase correction on and subpolarity +. What I hear is great but I think there is a lot of room for improvement. I wonder if anyone has nailed the set up. Reached out to REL and did not get back any response yet. 

Another thread about LS50W and REL sub integration....

https://forum.audiogon.com/discussions/kef-ls50-wireless-integration-with-rel-sub

randyhat

I wouldn’t use a sub larger than 2 x 8" max or at a pinch a very fast servo controlled 10" sub. As your crossing over from a 5.25" driver.
12" or 15" subs will be too slow to mate properly. I would also try blocking the port on the LS50 and going for around 100hz xover.
https://www.stereophile.com/images/1212KEF50fig3.jpg

And best maybe use two "tall" (24") subs and use them as stands for the LS50’s, like these I use, magic old Yamaha’s with servo control with linear amps
http://www.audioreview.com/product/speakers/subwoofers/yamaha/yst-sw305.html


Cheers George

I ended up with the REL-T7i.  I also was confused with all the options regarding the settings.  If you go to KEF they recommend running the sub at highest volume level and highest crossover setting and use the KEF DSP app to control the sub.  I talked to REL and got just the opposite advice.  They recommend minimal DSP activity on the KEF end and utilize the filters in the REL to control the sub.  Both KEF and REL support also suggest experimentation.  So there doesn't seem to be a consensus.  Having used RELs in the past and being accustomed to their recommended method for subwoofer hookup, I am following their advice....which means I am letting the LS50W run full range and controlling the REL to bring in the bass below the KEF.  I am not utilizing the high-pass option in the KEF app.I have the  sub low-pass frequency set to it's highest value (250Hz) and sub gain set to 0.  I use the controls on the REL to make all adjustments beyond that...and pretty much have done that by ear.  I started with the level and crossover settings at about 15 clicks from minimum and then adjusted from there by ear.  I tried virtually every combination of sub/kef settings and feel like the current setting offers the best integration.  As usual, many other factors will play into your decision but I have found what works for me.

Adjusting things by listening to them? What a concept...I'm not a DSP fan and having used a couple of RELs for years I found that adjusting them by ear is really easy. I put the RELs at the point where the mains lose their bass production ability, and adjust the level to taste. Done.

Exactly...