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Upgrading Sub from KEF-Q400 to REL T7X, does it make sense?

Mehdiem

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I’m wondering if upgrading my sub from KEF Q400 to one of the below candidates would have a noticeable impact on the purpose of music listening? In that case which sub (and size) would you go for?

- REL T7X
- KEF KC62
- I considered SVS Micro 3000 and loved the app, but I don’t like how it looks. So unless it’s significantly better than the above options, I prefer not to go for it.

My equipment are the following: amp= NAD 298, Preamp/DAC= RME ADI-2, speakers= KEF LS50, Streamer= Bluesound Node.

Note: I am planning to upgrade my speaker to a floor-standing speaker (or KEF R3) in the near future. Therefore, it would be great to get a sub that can integrate well with my future speakers (possibly B&W 702 s2, or KEF LS-60).

My room is irregular and acoustically untreated in the basements. Please see the flooring plan.
 

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timiark

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Not sure why you want to place your sub on that far corner. But anyways, I personally had listened T5x, KC62, and Micro 3000.

Pros:

T5x/T7x: smooth and gentle, integrate easily
KC62: dives deeper and well textured, and speedy
M3000: phone app EQ and reasonable extention.

Cons:
T5x/T7x: extension is at best misreable... you pay premium for a 30Hz -6dB sub... that's a bit unacceptable to me.
KC62: brand new unit is expensive and it can only go to around 90-95dB.
M3000: 20-30Hz region distortion is not well controlled and you need to tune it with phone app. (basically limit the volume) The look is ugly to me.

As you can see, if you want to fill your room with energy, I think you'd better off with M3000. For controlled bass, maybe KC62. But since your room is rather large, why don't you consider 12" SVS subs instead... SB1000 pro is much cheaper but dives as deep as KC62 while being much louder...
 
D

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Hi, if you want to fill that room with bass you’re going be better off going with two subs. A good rule of thumb is that two decent matching subs will outperform one better sub. I run 3 HSU VTF15h subs and they are incredible but not for everyone, and the customer service is outstanding.

You’ll have to do a sub crawl in that room to get the correct bass at the listening position, or measurements. I had a hard time getting the bass I wanted, the tactical impact I wanted for movies, so I went nearfield behind my listening positions. There are pros and cons of that also, and only you can weigh that out. So I would suggest adding another KEF sub as long as it performs well, adding a second one will make it perform much better.
 
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Peluvius

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I’m wondering if upgrading my sub from KEF Q400 to one of the below candidates would have a noticeable impact on the purpose of music listening? In that case which sub (and size) would you go for?

- REL T7X
- KEF KC62
- I considered SVS Micro 3000 and loved the app, but I don’t like how it looks. So unless it’s significantly better than the above options, I prefer not to go for it.

My equipment are the following: amp= NAD 298, Preamp/DAC= RME ADI-2, speakers= KEF LS50, Streamer= Bluesound Node.

Note: I am planning to upgrade my speaker to a floor-standing speaker (or KEF R3) in the near future. Therefore, it would be great to get a sub that can integrate well with my future speakers (possibly B&W 702 s2, or KEF LS-60).

My room is irregular and acoustically untreated in the basements. Please see the flooring plan.


How much time have you spent tuning the sub? A well tuned and positioned sub is the first large improvement and if you have already done that I would probably go for a second KEF Q400 first.
 
D

Deleted member 50971

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How much time have you spent tuning the sub? A well tuned and positioned sub is the first large improvement and if you have already done that I would probably go for a second KEF Q400 first.
Your post is right on the money, but also looking at his room I don’t think there’s any chance that one sub is going to get the bass he is looking for. It’s one of the hardest things to do in a theater setting, or even 2-channel sometimes. So yes add a second sub IMO.
 

BDWoody

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I’m wondering if upgrading my sub from KEF Q400 to one of the below candidates would have a noticeable impact on the purpose of music listening? In that case which sub (and size) would you go for?

I'd add one (or more) instead of replacing what you have. Multiple subs make tuning much easier, and tend to give a more even response.

I have 2 of the older passive HSU 10" cylindrical subs used as subs and speaker stands for my JBL 708s, and have mixed in my 12" Velodyne and 12" HSU subs with no issues.
 
D

Deleted member 50971

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How much time have you spent tuning the sub? A well tuned and positioned sub is the first large improvement and if you have already done that I would probably go for a second KEF Q400 first.
Your post is right on the money, but also looking at his room I don’t think there’s any chance that one sub is going to get the bass he is looking for. It’s one of the hardest things to do in a theater setting, or even 2-channel sometimes So yes add a second sub IMO.
 

FrantzM

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Hi @Mehdiem

Please do not take the following as a sermon: There is a Science underlying accurate reproduction in one's home. Hi-Fi is grounded in Science. That is one of the tenet of ASR, this forum.
You must apply Science to obtain the best results... ;)
First you need to measure. It is not easy and there is a learning curve.
It doesn't have to be expensive:
REW (Free)
UMIk-1 about $100.
A laptop .. (free? :D, yours :D)
Total:$100.oo

Then you measure, you research, you listen and you measure again :).

I will take a side step to address @timiark post:
Not sure why you want to place your sub on that far corner. But anyways, I personally had listened T5x, KC62, and Micro 3000.

Pros:

T5x/T7x: smooth and gentle, integrate easily
KC62: dives deeper and well textured, and speedy
M3000: phone app EQ and reasonable extention.

Cons:
T5x/T7x: extension is at best misreable... you pay premium for a 30Hz -6dB sub... that's a bit unacceptable to me.
KC62: brand new unit is expensive and it can only go to around 90-95dB.
M3000: 20-30Hz region distortion is not well controlled and you need to tune it with phone app. (basically limit the volume) The look is ugly to me.

As you can see, if you want to fill your room with energy, I think you'd better off with M3000. For controlled bass, maybe KC62. But since your room is rather large, why don't you consider 12" SVS subs instead... SB1000 pro is much cheaper but dives as deep as KC62 while being much louder...


I agree with all the cons... to a point but cannot leave the Pros unaddressed. We tend to take exception to such subjective assessments. They tend to mean nothing... "texture" "speed" are nonsenses carried over for too long by the subjecitivst audio scene/press. That is not a function of any subwoofer to provide "texture" and speed.. they rumble well or not.. that what they should do... they provide low frequencies...

This out...

It is possible to obtain good results with one subwoofer. Results are always better with more subwoofers, even lesser subwoofers. This is backed by Science. IOW you will get better results with adding more subwoofers, even different subwoofers , even a lesser subwoofer aka less expensive too ;). This requires works, lot of it but is achievable. You must measure to achieve such.

If you really want to have better bass in your abodes. Keep this subwoofer and add another one... I'd suggest an HSU or SVS.. Kef is too dear.. SVS , HSU, Monoprice, Rythmik , provide much better performance for your bucks.. As for REL , it should never figure in any reel discussion :) about subwoofers.. Overpriced but (of course) darling of the Subjective crowd, because of the usual higher price... and REL nonsense that you use the speakers' wires, as to save the character of the main speakers ... another pile of ...:mad::rolleyes:...

Take care

Peace.
 
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BALKAN_RAKIA

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Honestly the REL HT series is not bad at all, but I would stay away from all their other offerings. If I am you, and I have 1000 USD to spend on sub I would get two SVS 1000s - SP or PB - whatever you decide. However you might likely need something like MiniDSPHD to tune it and equalize it to the room. But it is going to be banging.
 

AwesomeSauce2015

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With that budget I'd say get 1 or 2 SB-1000 pro instead of a mini sub. They can come in black and white, and I personally think they look fine.

I can't recommend anything from REL. I recently was auditioning one of their subs (t/9x I think) in my room next to my SB-2000. The SB 2000 cost less and significantly outperformed the REL subwoofer in output and low & high extension.
The new SVS "pro" models , with the app and EQ, absolutely destroy anything REL makes.

REL "integrates well" compared to most other subs because they use a steep low-pass filter and do not have much sub-bass output. However, SVS's pro models allow selectable-slope low pass filters which are also adjustable over a wider range compared to what REL allows. Once you setup your crossover properly and use EQ to take down the big room modes, SVS's better extension and power really show.

Also: When I was auditioning the SVS and REL subwoofers, I set up a blind test between the t/9x and SB-2000. While the SVS model sounded "slower" at first compared to the REL, it soon became evident that the SVS was actually just outputting significantly more sub-60hz energy.
The REL was returned shortly after that test was completed.

Kef seems to make decent subs, but SVS has the best value right now.
 

Maginness

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I went through something similar not long ago. Room is difficult for placement and difficult to tune for. Dual subs was my solve.

I had an older MnK sub with two 12" drivers and MiniDSP and REW and DIRAC and... Never quite achieved the sound I wanted. Could get close but at a very specific listening position.

Ended up with dual SVS3000 Micros. The app is a deal maker if you don't have other room correction. The dual subs made balancing response much easier, they integrate amazingly, and the small cabniet size helps blend into the the room.
 
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