How much subwoofer output capability do you need in your system?

How come there aren't any Kef subs CEA-2010 output rated, out of interest?

If the red line, as implied, is how two KC62s do in room then I'm not sure how good CEA-2010 results would look :)

 
Good point. Although difficult to evaluate as the 13 has higher power amplification, so you can't only attribute the main distortion from the woofer size can you?

The distortion levels are discussed quite a bit by @AndreNewman a few pages back.

What would be really good is if CEA-2010 had a few figures for each measurement that fell in different "allowable distortion bands".
That's covered in some respects by CEA-2010-A-2012 I haven't bought the docs but I believe there's something about defining acceptable distortion differently at different frequency bands. For example 20Hz has a lot more allowable distortion than 80Hz, which_might_ be a reasonable real world compromise.

Funny no-one seems to test with CEA-2010-A only the super-ceded CEA-2010.
 
OK, in light of today's discussions, I've updated post # 1 as follows:

- The listening capability table based on 20Hz output now includes estimates of the potential dB uplift due to room gain at the bottom of the table for the various room sizes. Room gain of 7dB/octave is assumed which is SVS's minimum estimate for a sealed room and in lien with what THX obtained in its 3,000Ft3 Ultra spec test room with the Monoprice Monolith subs. I chose not to add it to the maximum volume figures as many members' rooms will not be sufficiently sealed to benefit from room gain and the result could be misleading.

- dB uplift factors for multiple (2, 3 & 4) subs at the base of the table

- A listening capability table based on 31.5Hz output has been added as an addendum.

- Text updated to reflect the above.
 
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@Mr Wolf thanks for adding the potential room gain and multiple subs gain factors, that is a big help to many I am sure:thumbsup:
 
How come there aren't any Kef subs CEA-2010 output rated, out of interest?

Speaker manufacturers rarely tells you them and/or they won`t send them to sites which test them fully. Most folks buying Kef sub adds them to hifi systems or light living room movie nights, they not intrested in these type of things. Probably more how compact cabinet, room & decor friendly the sub is to keep nagging wife happy.

Soundandvision has measured the Kef R400b sub (dual opposite 9" 400w). The figures are scaled to 1m peak, for comparison purposes subtract 9 dB. Notice the big drop in output below 40hz.

 
Most folks buying Kef sub adds them to hifi systems
You clearly aren't a Kef fan but the performance of the KC62, for example, is well-regarded (other than niggles over hum and a poorly implemented auto-standby) and has its own users' thread on AVF and elsewhere. It supposedly goes deep, maybe more than an SB1000 pro?
Probably more how compact cabinet, room & decor friendly the sub is to keep nagging wife happy.
The KC62 also has 2 x 500 watt amps, so not so small in that department.

Seems that if the SVS is on the list, then the KC62 should be too? :)
 
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You clearly aren't a Kef fan but the performance of the KC62, for example, is well-regarded (other than niggles over hum and a poorly implemented auto-standby) and has its own users' thread on AVS and elsewhere. It supposedly goes deep, maybe more than an SB1000 pro?

The KC62 also has 2 x 500 watt amps, so not so small in that department.

Seems that if the SVS is on the list, then the KC62 should be too? :)

Hiya, there isn't any prejudice going on with the subs on the list 🤣

It's based on if there are decent/proper CEA-2010 results. I don't think there are any for the KC62.

And it would be very interesting to see comparative results to the SB-1000 Pro. I'd put my money on the SVS - so who's offering bets? 😂
 
Hiya, there isn't any prejudice going on with the subs on the list 🤣
I'm sure there isn't and I wasn't implying there was. ;)

I was just reacting to the references to 'hifi system owners' and 'keeping nagging wives happy', which came across as mildly derogatory.

Noted though that lack of decent/proper CEA-2010 results precludes the Kef from the list. I have no issue with that whatsoever
I'd put my money on the SVS
Cool. Am a new SB1000 pro owner myself as it happens 👍
 
The Kef's have a similar behaviour to the B&W DB range, they have some strong DSP that allows them to hit specific frequencies but only at specific levels.

From memory the Kef hits something like 11Hz, but only at <80dB. If you increase the volume the 11Hz point is pretty fixed. The slope above that becomes steeper and I don't remember at what frequency the SPL starts to increase properly, I think it's well above 20Hz.

This makes them (and the B&W subs) excellent for music and low level listening but not so good for home cinema. Two 6.5 drivers are only ever going to be able to shift so much air.

The same is likely true of the SVS 3000 micro.
 
The Kef's have a similar behaviour to the B&W DB range, they have some strong DSP that allows them to hit specific frequencies but only at specific levels.

From memory the Kef hits something like 11Hz, but only at <80dB. If you increase the volume the 11Hz point is pretty fixed. The slope above that becomes steeper and I don't remember at what frequency the SPL starts to increase properly, I think it's well above 20Hz.

This makes them (and the B&W subs) excellent for music and low level listening but not so good for home cinema. Two 6.5 drivers are only ever going to be able to shift so much air.

The same is likely true of the SVS 3000 micro.

I assume you are refering to larger KC92 model (2x9" with same 1kw amp). The KC62 is very tiny with 2x 6,5" drivers. 246 x 256 x 248 mm. This is pure nearfield 2.1 sub or light cinema in small apartment room, it does have high WAF. The specs should be taken as grain of salt.

3000 Micro (2x 8" 800w) is step up from KC62 at least with movies via real life comparisons.

You clearly aren't a Kef fan but the performance of the KC62, for example, is well-regarded (other than niggles over hum and a poorly implemented auto-standby) and has its own users' thread on AVF and elsewhere. It supposedly goes deep, maybe more than an SB1000 pro?

The KC62 also has 2 x 500 watt amps, so not so small in that department.

Seems that if the SVS is on the list, then the KC62 should be too? :)

High power won´t help much cause it has so small cabinet with drivers that are often found in bookshelf speakers. It won´t hold candle to SB1000 Pro (cinema) which also outperforms the more expensive Micro 3000 below 30hz at least.
 
I assume you are refering to larger KC92 model (2x9" with same 1kw amp). The KC62 is very tiny with 2x 6,5" drivers. 246 x 256 x 248 mm. This is pure nearfield 2.1 sub or light cinema in small apartment room, it does have high WAF. The specs should be taken as grain of salt.

Nope, the 62. Their specs are a little misleading, they have it specced at a max spl of 105dB and a frequency response down to 11Hz. They're both true, but not together. As I say, I've seen measurements of it hitting 11Hz and that point not moving as the volume increases.

That's not a bad thing, it's a design choice as allowing it to hit those frequencies at any decent SPL would likely introduce enormous amounts of distortion and possibly stress and damage the unit. Also, that's not what it's for. Nobody's buying a 25cm cube and expecting room rocking output. At least I hope not.
 
Nope, the 62. Their specs are a little misleading, they have it specced at a max spl of 105dB and a frequency response down to 11Hz. They're both true, but not together. As I say, I've seen measurements of it hitting 11Hz and that point not moving as the volume increases.

That's not a bad thing, it's a design choice as allowing it to hit those frequencies at any decent SPL would likely introduce enormous amounts of distortion and possibly stress and damage the unit. Also, that's not what it's for. Nobody's buying a 25cm cube and expecting room rocking output. At least I hope not.

Ok, i just remember we talked about KC92 last time with some graphs and the 11hz spec. I can´t remember 62 talked much in technical sense, but anyway... No mention how the 105db is measured (mic distance) and at what frequency, of course it`s higher up. Good marketing from Kef and B&W as they put low hz figures there, but the reality can hit hard then when people find out no earthquake bass and i see many issues with these on owners thread with short warranty. Optimal room size for KC62 up to 50m2 made me chuckle little bit. For the KC92 it`s up to 100m2. 🤪
 
Nope, the 62. Their specs are a little misleading, they have it specced at a max spl of 105dB and a frequency response down to 11Hz. They're both true, but not together. As I say, I've seen measurements of it hitting 11Hz and that point not moving as the volume increases.

That's not a bad thing, it's a design choice as allowing it to hit those frequencies at any decent SPL would likely introduce enormous amounts of distortion and possibly stress and damage the unit. Also, that's not what it's for. Nobody's buying a 25cm cube and expecting room rocking output. At least I hope not.
yeah it's on the KC62 webpage, but hidden away via a link to the white paper.
It never gets much past about 80dB for 11hz.

The room gain KEF are roughly applying is: 12dB for 10hz, 10dB for 20hz, and 6dB at 40hz.

Is this inline with Wasp's 7dB/octave, doesn't seem to be, so are KEF being a little 'optimistic' perhaps to make it look better? As I'm not sure the implied ~100dB at 25hz is probably feasible from that little box even with room gain?!

Screenshot 2022-02-23 at 16.28.48.png
 
Can you do svs SB ultra v two monolith 13" get idea. They won't be stacked, be either side of the TV
 
Can you do svs SB ultra v two monolith 13" get idea. They won't be stacked, be either side of the TV
1645813407790.png


This assumes 4dB SPL summation from dual subs. In practice the level of summation will vary by frequency.
 
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Can you do svs SB ultra v two monolith 13" get idea. They won't be stacked, be either side of the TV

I reckon you're gonna see more of a delta than I did with my upgrade. Especially very low frequencies. :)
 
How about dual 15" monoprice compared to dual 13" monoprice, kenshoggi wants to know hehe
 
Can I get a graph for 4xMono 15 vs 2x Mono 13 vs 2x Mono 16 whenever you have a chance mate!

(sorry i know its a bit awkward and the 4x subs are going to cover more nulls and improve localisation).

I'm wondering if I can snap up a cheeky 2x Mono 15 on sale as they clear old lines ( a long shot I know).

I didn't realise how big the 16s are depth wise so its messed up my plans very slightly. although I could just put them up height wise but I weirdly like them on their side as they act as seating in a pinch.
 
These are Audioholics' CEA-2010 measurements for single subs.

1645960683006.png


Simply add 4dB for duals, 8dB for four subs to these figures for any comparisons between the options you're looking at as you should expect at least this level of output summation.

A 3,000Ft3 room should get 9dB of boundary gain and going dual should add at least 4dB over a single so that's 13dB more than a single sub measured under CEA-2010. As reference level output is 115dB, if going dual you therefore only need 102dB from a single sub to hit reference level and that's not taking account of any potential room gain. It's clear from this that all you would be gaining is more headroom which may or may not translate into a perceptible increase in performance.

Provided you don't mind their rougher finish, personally I would favour four 15" THX subs over a pair of either of the other two as four is considered the ultimate set-up for an even in-room response with zero localisation.
 
These are Audioholics' CEA-2010 measurements for single subs.

View attachment 1660505

Simply add 4dB for duals, 8dB for four subs to these figures for any comparisons between the options you're looking at as you should expect at least this level of output summation.

A 3,000Ft3 room should get 9dB of boundary gain and going dual should add at least 4dB over a single so that's 13dB more than a single sub measured under CEA-2010. As reference level output is 115dB, if going dual you therefore only need 102dB from a single sub to hit reference level and that's not taking account of any potential room gain. It's clear from this that all you would be gaining is more headroom which may or may not translate into a perceptible increase in performance.

Provided you don't mind their rougher finish, personally I would favour four 15" THX subs over a pair of either of the other two as four is considered the ultimate set-up for an even in-room response with zero localisation.

Thank you mate. I love the rougher finish as I'm very into wood grains and all that crap as I prefer traditional to modern decor. The grille is crap though.

Your thoughts are basically what I thought in the back of my mind too. As far as I'm aware, the new big boys aren't offering lower extension and roll off at the same port tune or similar so 4x 15s (If I can fit them in) might be the best for my setup as I'll probably have no nulls.

No idea what I'd put it.. I have ONE spot in mind for a third. Hopefully they start going on clearance.
 
Anyone know dimensions of box? Hope it can get through front door
 
Hi mr Wolf , do you know if 2 svs sb 1000 non pro will be enough for a 13x13 x 8 feet room, I won’t be near reference volume, thank you
 
Hi mr Wolf , do you know if 2 svs sb 1000 non pro will be enough for a 13x13 x 8 feet room, I won’t be near reference volume, thank you
Their max output is probably about a couple of dB below the Pro version so a pair should be good for up to about -10dB volume in a room that size. Possibly a bit higher if the room is sealed and you’re getting some room gain. That’s enough for most people’s listening levels.
 
@Mr Wolf when you have time can you edit the HSU VTF 15H, change it to MK2 (which almost doubles amp power) as you have the old model figures taken from 2006 review:

The new one can be found below. Will you put 1 port mode or 2port mode is up to you, first one shows higher output for 20hz, but lower at 30 & 60hz. Also can you add the VTF3 MK5 HP which is missing from the list. The 2M RMS figures for both models are listed side by side so it`s very easy to add them.

👍

If you look closely they offer quite superb performance for VERY low prices, dual sub deals are even better!
 

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