Help! BK Subwoofers; Experience of Hi-Fi Use (Arcam Separates and KEF Q4 Speakers)

StuG69

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Hey forum!

I could really use some help and experience, please!

In summary, I have a 7M x 3.5M lounge, effectively split into two areas in terms of audio; at one end I have a TV and a 5.1 A/V set-up, in the other I have a little separates setup just for 2 channel music; all pretty vintage kit (apart from an AT-LP120XUSB turntable) comprising an Arcam Delta 290 amplifier, Arcam Alpha 7 CD player and KEF Q4 speakers.

Whilst I have a sub for the A/V end, and knowing that I could connect this to the Delta 290 amp I would prefer to keep it all separate, one for chilling/listening to music and the other for films/family/TV/entertainment.

Essentially, I want to add a sub to compliment the Q4s. A lot of research has lead me to the BK range and that's where I'm struggling a little. I am looking XLS300, XLS400 and Platinum P12-300 yet having heard none in 'the metal' I'm really open to advice and experience from others who are using BK subs specifically with getting some low end into their music listening. For what it's worth, the Q4 are firing down the 7M length, not across the width of the room. I listen to everything bar rock/metal but with a real interest in earlier analogue synth based music right up to big room trance and tech-trance styles, with a bit of Elbow or Passenger thrown in for good measure!

The KEF blurb:

System type3-way
Enclosure typeBass-reflex
Frequency response ± 3dB42 - 27000 Hz
Nominal impedance8 Ohm
Amplifier Requirements15 - 150 W
Sensitivity (2.83V/1m)90 dB
Maximum output (SPL) 111 dB
Midrange130 mm (5") Uni-Q with 19 mm (3/4") HF
Woofer130 mm (5")


Some things I've learned that might help my choice: a sub with a forward (side) facing driver and Neutrik connected to the Arcam high level likely the better for my use and finally, I am not averse to 2nd hand/eBay purchases, BK's own 'seconds' sale, etc. but I must have about 30 items in my watch list currently and that's just going to increase further unless I reach out for help to try to stop my spiralling procrastination!

Many thanks in advance of your opinion/experience!

Stu
 

twinkletoes

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there alright personally nothing to right home about.
you have a very large space to fill only the very largest of subwoofers are going to pressurise that so you need to tamper you expectations a little in regards to presence.

brands id look look to second hand are velodyne and SVS, they have very very robust drive units.
 

StuG69

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there alright personally nothing to right home about.
you have a very large space to fill only the very largest of subwoofers are going to pressurise that so you need to tamper you expectations a little in regards to presence.

brands id look look to second hand are velodyne and SVS, they have very very robust drive units.
Hiya!

That all makes sense and yes, The KEF are hardly setting the space on fire but they're Wife friendly (read also as I am a coward, but a coward who's going to try to disguise a new sub!) My listening position is only 2M away from the KEF's, hard to explain so have added a quick mock-up. I already have an AV system inthe other half of the room but I can't use the sub (Videologic Pure 10, active) as it it 7M away from the KEFs. Essentially, I want a music system sub for that 'end' of the room, rather than for the whole of it if that makes sense? Velodyne and SVS look stunning but might be out of my price range. I could be swayed. I could also be tempted to replace the Q4's too!

Many thanks,

Stu
 

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John Fulwood

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This is a dilemma. I'm also in the market for a 2 channel system sub to go with my Sugden A21SE, Chord Qutest and pair of hand made Mycelias speakers. I have a BK Monolith Plus sub in my main living space which is 10m x 11m and it can make the kitchen cabinets rattle with movies. I carried it up to my music room on the weekend (46kg) to plug into my system - OMG, what a difference it made, it was remarkable (but it is freaking huge). But, I am going to try a REL t/9x or S/510. I keep reading about how musical they are, but need to try one in the room, which is 4.6 x 4.6 x 3.3m with a large bay window.
The dilemma is looks vs price vs performance. If I go BK it will need to be down firing as they don't look great but I think it also is not the best for 2 channel? The Rel's look much better with and without the grills, so they would be okay. However, the Rel's are 2x plus the price. In the end, I will test and best sound wins.
My experience of the BK's, which was your original question, has been great. I bought a 2nd from their eBay shop and I have been all over it with a magnifying glass and I can't find anything wrong with it. Performance wise, it is a few years old and has never missed a beat.
 
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roaduck

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I will second John Fulwoods advice about the BK range Monolith plus - I have a forward firing one and it can do 15hz in room and 20hz at over a 100 decibels cleanly with no bottoming out.
The BK XLS400 being sealed sounds fabulous for music and isn`t exactly shy with movies either.
Compared to a 12 inch SVS it sounds a bit better for music IMHO even though it is only 500 watts with 1KW peaks the Eminence LAB 12 driver at 26 lbs alone is a very good woofer and can take a lot of abuse without breakdown.
I have Eminence 12" drivers in my Danley spud horn sub and it vibrates the pavement outside from inside the house but is not one note boomy at all.
It is over 300lbs and well over five times the size of a Monolith though.
I fell in love with Danley in Georgia, USA when I heard some middle of the road stuff played from 700 foot away in a car park and it was over 85 db but clean as a whistle.
BK used to manufacture for REL so they certainly know their onions; the customer service is unsurpassed and that is coming from someone who used to flog high end and bespoke kit in China ages ago.
 
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I will second John Fulwoods advice about the BK range Monolith plus - I have a forward firing one and it can do 15hz in room and 20hz at over a 100 decibels cleanly with no bottoming out.
The BK XLS400 being sealed sounds fabulous for music and isn`t exactly shy with movies either.
Compared to a 12 inch SVS it sounds a bit better for music IMHO even though it is only 500 watts with 1KW peaks the Eminence LAB 12 driver at 26 lbs alone is a very good woofer and can take a lot of abuse without breakdown.
I have Eminence 12" drivers in my Danley spud horn sub and it vibrates the pavement outside from inside the house but is not one note boomy at all.
It is over 300lbs and well over five times the size of a Monolith though.
I fell in love with Danley in Georgia, USA when I heard some middle of the road stuff played from 700 foot away in a car park and it was over 85 db but clean as a whistle.
BK used to manufacture for REL so they certainly know their onions; the customer service is unsurpassed and that is coming from someone who used to flog high end and bespoke kit in China ages ago.
After six months it might be possible he has already found one... :)
 
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John Fulwood

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Hey Roaduck and Al ears, I still have the Monolith plugged in and it still sounds great - but it is massive - see pic.
I borrowed a REL 9x from Richer Sounds (shout out to Preston and REL for sorting that - they could not be anymore helpful) for a few days. On first listen I thought it was too weak, but persisted with it thinking it might just take a bit of getting used to - I couldn't justify the price point for the performance in my set-up, that is to say that the room size etc. may be the issue, not the quality of the REL.
I'm still in the market, but I'm probably going to try a pair of Harbeth HL5 Plus speakers before testing another sub.
 

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