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SUB + Stereo System

Jim Matthews

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#81
So he should do what particularly since he's not likely to change rooms?
Given that the - 3dB point with the main speaker is 80 hZ, I would want to optimize corner loading, first. I would not recommend expensive solutions (including the best available equipment) in a room with so many likely sources of destructive interference.

Given the volume of the room and the multiple corners, I'm doubtful the mains are placed optimally and the Hegel amp has sufficient headroom to generate higher SPL.

My guess (and it's just that- a guess) is that the setup is quite new and the OP is disappointed with the performance in this unusual room.

Color me doubtful that meaningful bass material below 40 Hz is likely given the first two side wall lengths.
 

hawk01

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#82
Thank you guys for the advice. Truly helpful.

I will purchase the kef kc62 that has a high pass filter with the potential to utilise that later.

I will not purchase a dac at the moment but its something that has been on my list from the outset. The choice of the sub and dac could potentially affect one another and thats why i brought it up.

:)
i checked your room floor plan again. by the looks of it you may have at least 30sqm of floor area in a very irregular shaped room. you intend to buy a single piece of KEF KC62 subwoofer to fill in an irregular shaped room with (hopefully) satisfying bass. i am not very sure how capable the KEF subs are and your reasons for buying them and that is your choice to make.

let me give you an idea of what actual performance feels like. my dedicated home theater/stereo room is rectangular and only 20.5sqm. i have dual SVS SB1000s connected to a humble yamaha RXV-481 avr with revel M16 front stereo pair. the M16s on their own already have impressive bass running fullrange but can sound boomy depending on material. however, when avr bass management is enabled with the dual subs there is nothing i can play that will boom the room! seriously it is that good! the dual subs are also assymetrically and diagonally opposed near the front and rear corner of the room. i can set the sub gain to a higher value and i get louder and more importantly still clean bass due to proper integration thru the avr settings.

to give you more useful info, the dual SB1000s were previously in my 30sqm. master bedroom setup. while they were able to provide decent amounts of quality bass, it was not the same when i only had a single SB1000. ergo the only way around it was dual subs! with dual subs you get decent output and more importantly a more even bass response. now my master bedroom has a single SVS PC2000 doing bass duties. this time even if was single sub it is still able to shake the room with decent conviction due to sheer output. you may want to look closely if the KEF sub can match or exceed the PC2000 output.

the takeaway from all this is already blocked and italicized above.
outlined below are your key considerations:
1. expect unpredictable bass response due to the irregular shaped room. a single sub will not do you any favors dealing with this dilemma.
2. you have 30sqm to fill with decent bass. depending on your preference, do you think the single KEF sub can deliver given the facts above??
3. you can never have too much subwoofer in any given room. it is always easier to crank it down than having it run full steam and still have inadequate bass.
4. there is no way around proper bass integration or bass management. YMMV if you choose to play it by ear or go the minidsp route.
5. if you had the hegel amp on the get go, perhaps you should have invested in larger floorstanders instead of the expectedly anemic KEF metas in a 30sqm room. might be worth swapping the KEFs for something more substantial if you still have the time. with larger floorstanders you may find some contentment without having to integrate subwoofers into the mix making for less clutter in the system.

HTH and cheers!

PS i checked the KEF KC62 at US$1599++ SRP. i think you can buy 3pcs of SB1000s for this amount and get on with your life in audio bliss!
 

Lorenzo74

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#84
How can I do bass management and pass lower frequencies only to the sub?

Using some a minidsp that has a dac?
The investment is limited with Minidsp DDRC24.
what you have is digital XO with 48dB octave and Dirac live.
Plus remote controlled digital volume and 3 inputs: USB, Toslink, Analog.
What else?
It sounds good to my ears but if someone feel the need for better numbers… just double the price and go for Minidsp SHD which also add streaming capabilities.
hope this help
best
 
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Georgeadv

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Thread Starter #85
i checked your room floor plan again. by the looks of it you may have at least 30sqm of floor area in a very irregular shaped room. you intend to buy a single piece of KEF KC62 subwoofer to fill in an irregular shaped room with (hopefully) satisfying bass. i am not very sure how capable the KEF subs are and your reasons for buying them and that is your choice to make.

let me give you an idea of what actual performance feels like. my dedicated home theater/stereo room is rectangular and only 20.5sqm. i have dual SVS SB1000s connected to a humble yamaha RXV-481 avr with revel M16 front stereo pair. the M16s on their own already have impressive bass running fullrange but can sound boomy depending on material. however, when avr bass management is enabled with the dual subs there is nothing i can play that will boom the room! seriously it is that good! the dual subs are also assymetrically and diagonally opposed near the front and rear corner of the room. i can set the sub gain to a higher value and i get louder and more importantly still clean bass due to proper integration thru the avr settings.

to give you more useful info, the dual SB1000s were previously in my 30sqm. master bedroom setup. while they were able to provide decent amounts of quality bass, it was not the same when i only had a single SB1000. ergo the only way around it was dual subs! with dual subs you get decent output and more importantly a more even bass response. now my master bedroom has a single SVS PC2000 doing bass duties. this time even if was single sub it is still able to shake the room with decent conviction due to sheer output. you may want to look closely if the KEF sub can match or exceed the PC2000 output.

the takeaway from all this is already blocked and italicized above.
outlined below are your key considerations:
1. expect unpredictable bass response due to the irregular shaped room. a single sub will not do you any favors dealing with this dilemma.
2. you have 30sqm to fill with decent bass. depending on your preference, do you think the single KEF sub can deliver given the facts above??
3. you can never have too much subwoofer in any given room. it is always easier to crank it down than having it run full steam and still have inadequate bass.
4. there is no way around proper bass integration or bass management. YMMV if you choose to play it by ear or go the minidsp route.
5. if you had the hegel amp on the get go, perhaps you should have invested in larger floorstanders instead of the expectedly anemic KEF metas in a 30sqm room. might be worth swapping the KEFs for something more substantial if you still have the time. with larger floorstanders you may find some contentment without having to integrate subwoofers into the mix making for less clutter in the system.

HTH and cheers!

PS i checked the KEF KC62 at US$1599++ SRP. i think you can buy 3pcs of SB1000s for this amount and get on with your life in audio bliss!
Hello and thank you for your feedback!

Please refer to the measurements i posted
There is a lot of room gain lower down the frequencies. In fact, am experiencing bloated bass which i intend to manage with eq and room treatment..
The ls50 in my room go down to 40hz at 75db, that isn’t anaemic i believe. Purchasing floorstanders would not help me with room resonances due to placement..
with a sub I can use the befefit of placing it anywhere in the room, something which i couldnt do with floorstanders…

In any case, the measurements have to be taken into account
 

Jim Matthews

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#86
Hello and thank you for your feedback!

Please refer to the measurements i posted
There is a lot of room gain lower down the frequencies. In fact, am experiencing bloated bass which i intend to manage with eq and room treatment..
The ls50 in my room go down to 40hz at 75db, that isn’t anaemic i believe.
In any case, the measurements have to be taken into account
I haven't seen a waterfall plot of this, but I'm suspicious of a 40 Hz mode that is ringing. The peak at 40 Hz probably dominates bass response.

See the orderly peaks at 40, 80 and 120 Hz in your graph - and perhaps even higher into midrange frequencies? This procession of accentuated tones followed by "nulls" is a hallmark of interference effects.

I'll leave it at this: until you have optimal placement of your main speakers (which are a technical marvel) additional gear will not likely solve your fundamental problems.
 

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SKBubba

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#87
Definitive Technology ProSub 1000

Appears to be available in Europe.

Has speaker level input and high pass speaker level outputs. So speaker out from amp wired to sub then from sub to main l/r speakers.

No idea about the quality/reliability but appears to do what you want.
 
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Georgeadv

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Thread Starter #88
I haven't seen a waterfall plot of this, but I'm suspicious of a 40 Hz mode that is ringing. The peak at 40 Hz probably dominates bass response.

See the orderly peaks at 40, 80 and 120 Hz in your graph - and perhaps even higher into midrange frequencies? This procession of accentuated tones followed by "nulls" is a hallmark of interference effects.

I'll leave it at this: until you have optimal placement of your main speakers (which are a technical marvel) additional gear will not likely solve your fundamental problems.
Here is the waterfall. You mean SIBR ?

If so, i cant move them closer to the wall, the bass gets worse, it tried
 

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Georgeadv

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Thread Starter #89
Definitive Technology ProSub 1000

Appears to be available in Europe.

Has speaker level input and high pass speaker level outputs. So speaker out from amp wired to sub then from sub to main f/r speakers.

No idea about the quality/reliability but appears to do what you want.
Hey! Hegel said that wont work :S
 

SKBubba

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#90
Hey! Hegel said that wont work :S
Why? It's outside the amp signal path. The passthru is from speaker to speaker, no amp/pre-amp loop involved. Would assume the sub has some sort of impedence/load matching to make it transparent to your amp, but don't know for sure.
 
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Georgeadv

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Thread Starter #91
Why? It's outside the amp signal path. The passthru is from speaker to speaker, no amp/pre-amp loop involved. Would assume the sub has some sort of impedence/load matching to make it transparent to your amp, but don't know for sure.
The amp will send full signal to the speakers. It requires separates
 
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Georgeadv

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Thread Starter #93
The amp will send full signal to the sub. The sub will send lf to the sub speaker and hf (>=80hz) to your mains.
Thought that myself but apparently the amp will pass the signal to the speakers and the sub. It needs an external dac with preamp or separates
 
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SKBubba

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#94
Though that myself but apparently the amp will pass the signal to the speakers and the sub. It needs an external dac with preamp or separates
The amp cannot send the same signal to both the sub and your main speakers because the amp is not connected to your main speakers. Instead, your amp is connected to the sub, and your mains are connected to the sub. The sub splits the amp speaker output and sends hi pass speaker output to your mains, sort of like an external crossover. (Can't speculate on how it affects final sound quality at your main speakers, though.)

There used to be more subs with this type of setup, but my impression is that it is less common now because nowadays subs are most likely used with an AVR or pre-processor or integrated amp with bass management. Hopefully, more 2 channel integrated amps will include bass management in the future.

Anyway, the only reason for my suggestion was that it was an interesting problem and I was familiar with this approach to solving it. It appears I'm not communicating it very well, so my apologies. Hope you figure out a solution that works for you. And, enjoy the music!
 
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Georgeadv

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Thread Starter #95
Ah sorry i did not understand that properly.

Yes that would work but wouldn’t the sub powering the speakers that way? Hegel would be wasted
 

SKBubba

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#96
Ah sorry i did not understand that properly.

Yes that would work but wouldn’t the sub powering the speakers that way? Hegel would be wasted
That was not my impression, but if so that would not be good. Guess you'd have to ask the manufacturer.
 

Jim Matthews

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#97
You mean SIBR ?

If so, i cant move them closer to the wall, the bass gets worse, it tried
I think these are room modes, and they are further distributed by all of the corners along the left side walls. If moving the mains closer to the rear wall makes this mode more pronounced, additional bass energy from another source (like a subwoofer) will increase the peaks shown in your waterfall plot.

I think pursuit of some absorption panels would be the logical (and least expensive) first step. I would hazard a guess (and it is just that - I'm not a qualified acoustician) that a "half round" trap along the two left walls might capture and delay some of the 40 Hz nodes without dominating the room.

An example is shown in the link, below.
https://www.acousticsciences.com/product/half-round-tubetrap/
 
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Georgeadv

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Thread Starter #98
I think these are room modes, and they are further distributed by all of the corners along the left side walls. If moving the mains closer to the rear wall makes this mode more pronounced, additional bass energy from another source (like a subwoofer) will increase the peaks shown in your waterfall plot.

I think pursuit of some absorption panels would be the logical (and least expensive) first step. I would hazard a guess (and it is just that - I'm not a qualified acoustician) that a "half round" trap along the two left walls might capture and delay some of the 40 Hz nodes without dominating the room.

Yep, i already ordered some acoustic treatment, bass traps mainly for the back and front walls.

Subwoofers are a lot cheaper than ready made acoustic treatment

An example is shown in the link, below.
https://www.acousticsciences.com/product/half-round-tubetrap/
 

Beershaun

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#99
That was not my impression, but if so that would not be good. Guess you'd have to ask the manufacturer.
If you have the budget, I like this idea. If you can get 2 subwoofers, run one on each channel with the capability to perform the crossover and pass the amplified high frequency through to the KEFs and the low frequency goes to the sub amp and played by the sub. You can set them up to simulate a 3 way speaker. The challenge will be dialing in the two subs with room correction. I think you could accomplish this with Room EQ Wizard and a umik-1 microphone. Then using the individual subwoofer EQ capabilities to adjust them independently.

I'll re-iterate @SKBubba, call the subwoofer manufacturer and tell them about your situation and setup and see what they recommend. Then find out if they have an "in-home" demonstration period where they can ship you the sub to trial setting it up and return it if you are unhappy.
 

Beershaun

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