Tap lightly on the center face of any LCD television screen while it's turned on..... what do you notice in the video?
Some blurring? - distortion of the picture?
Now, add a sub woofer nearby, and play a movie with some nice heavy cannon explosions or some cRap music.....
If the picture distorts, I don't need to go any further.
Some blurring? - distortion of the picture?
Now, add a sub woofer nearby, and play a movie with some nice heavy cannon explosions or some cRap music.....
If the picture distorts, I don't need to go any further.
Why not 2 woofers in one cabinet ?
It will be identical woofers running parallel of the same amp output.
I have seen the minidsp offerings but that adds to the complexity.
Now I have a DIY streamer/DAC --> pre-amp --> power amp --> speakers.
For the subs I will use the pre-amp out --> plate amp --> subs.
In general I will not place several subs in the room for best result (WAF !!)
I have to deal with the space within the frame.
I will have sufficient space between the woofer and the floor ... approx. 4-6 inch depending on the shape and height chosen for the cabinet.
The wall is a brick wall so no flex or absorption from the rear wall.
The frame + wooden beams are approx. 230 kg with a 150 kg wood burner on top.
I guess there will be enough mechanical mass to damp any vibration.
The TV is located to the left and the subs will be installed at the right side under the frame.
And that is all nice and dandy....
However, what you're not understanding by my post is the AIR MOVEMENT of substantial sub bass.
You think large heavy solid furniture will cure any vibrations, yet fail to take into account the waves of bass traveling theough the air.
I've got a secretary desk and a china cabinet in my dining room, and quite a distance away I've got a console stereo with two 12 inch woofers in it.
When I crank that console up, the glass panels in those cabinets vibrate quite noticeably.
Further Recommendation
It may be simpler to foreshorten the steel frame and use the down/back firing sub enclosures as supporting pedestals at each end of the credenza. Also, the acoustic benefit of doing this, is that it places each sub unit close to a satellite unit. This placement will allow a higher c/o frequency to be used that will increase system output headroom. I suspect that such placement will mitigate room modes to some improved degree as well. WHG
It may be simpler to foreshorten the steel frame and use the down/back firing sub enclosures as supporting pedestals at each end of the credenza. Also, the acoustic benefit of doing this, is that it places each sub unit close to a satellite unit. This placement will allow a higher c/o frequency to be used that will increase system output headroom. I suspect that such placement will mitigate room modes to some improved degree as well. WHG
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The suggestion seems like a good idea but to modify the frame will have major consequences.
The whole credenza needs to be dis-assembled including the woodburner.
For that I would need the installer to remove it and install it back afterwards.
To replace both outer steel supports by a wooden (subwoofer) box will discard the open feel below the credenza.
It will be too much hassle not even considering the needed wife approval
What ever we come up with must fit the original requirements and the invisible box hanging under seems the only possible option.
The whole credenza needs to be dis-assembled including the woodburner.
For that I would need the installer to remove it and install it back afterwards.
To replace both outer steel supports by a wooden (subwoofer) box will discard the open feel below the credenza.
It will be too much hassle not even considering the needed wife approval
What ever we come up with must fit the original requirements and the invisible box hanging under seems the only possible option.
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With 2 boxes you have more placement options. 1 in the corner and 1 somewhere close is probably best.
Connecting the sub woofer box(es) to the frame probably adds extra resonances/ noise.
preamp -> minidsp ->main + sub amps -> all speakers
Then you can use the mini dsp as crossover as well to cut off the lows from the main speakers and you can also adjust/fine tune them to the room.
@Oystein, this is the second time in 24 hours I’ve recommended this build but you might be able to make it truly hidden for your requirements: Hideaway TL Sub Revisited | audioXpress
Bjorn’s work is well known here. Worth a look at any rate; perhaps it will inspire you further.
Bjorn’s work is well known here. Worth a look at any rate; perhaps it will inspire you further.
UPDATE AFTER 3 YEARS :
I left this project unattended for 3 years already ... time flies when you are having fun
Of course I had some ideas what to do and what was needed for that.
The subwoofer required also a change in hifi equipment and I made a final decision how to continue.
I will buy a Lyngdorf TDAI-1120 to power the Boenicke W5 speakers directly (2x 60W) and use the line out to feed my separate power amp to drive the subs which can output approx 2x 180W @ 4 ohm.
The Lyngdorf has an adjustable hi-pass / low-pass filter and on top of that their "RoomPerfect" DSP room adjustment.
Which now leaves the final details for how to build the subs.
I have decided on a closed box so please do not start a discussion on other concepts. The closed boxed is fixed
To copy some details from my initial post from page 1 some pictures to understand what I mean.
The initial frame to work with which is normally hidden under the wooden beams.
Width of the frame is 280 cm and between the 3 main stands is 130 cm each side.
The equipment will move to the green section which leave the orange section available for the subs enclosure.
This is a side view of the subs enclosure (blue) with the steel bars (black) and the wooden beams (orange)
The main objective is to have the enclosure invisible when sitting on the couch. The rear height of the subs enclosure can extend probably a little lower due to the line of sight from the seats which also increases the internal volume.
The external volume is approx. 170 liters and will put in 2 subwoofer units 12 or 15 inch operated mono in the same box volume .. still working in the final details but I will cope with that.
The internal volume will be approx. 120 litres.
One of the challenges is how to mount the encolusure ?
I could rest it on the steel frame (with spikes) but I am thinking about to screw the top of the enclosure directly to the underside of the wooden beams from inside the subwoofer box.
The beams themselves are fixed with M8 bolts to the steel frame at all 3 main stands so it is fairly rigid.
The wood burner on top adds to the total mass so I guess it should not resonate.
Also the total mass of the whole construction is considerable: total 430 kg
steel frame: 20 kg
5 wooden beams: 240 kg
stone slab under wood burner: 40 kg
wood burner: 130 kg
Are there any objections for the subwoofer performance to mount it like that ?
The whole construction stands only on the floor and is not attached to the rear wall, the neighbours should not get any clue about my upgrade
When everything is done it will still look like this ... no visible equipment and only the Boenicke W5 in the room which are nice to look at anyway
I left this project unattended for 3 years already ... time flies when you are having fun
Of course I had some ideas what to do and what was needed for that.
The subwoofer required also a change in hifi equipment and I made a final decision how to continue.
I will buy a Lyngdorf TDAI-1120 to power the Boenicke W5 speakers directly (2x 60W) and use the line out to feed my separate power amp to drive the subs which can output approx 2x 180W @ 4 ohm.
The Lyngdorf has an adjustable hi-pass / low-pass filter and on top of that their "RoomPerfect" DSP room adjustment.
Which now leaves the final details for how to build the subs.
I have decided on a closed box so please do not start a discussion on other concepts. The closed boxed is fixed
To copy some details from my initial post from page 1 some pictures to understand what I mean.
The initial frame to work with which is normally hidden under the wooden beams.
Width of the frame is 280 cm and between the 3 main stands is 130 cm each side.
The equipment will move to the green section which leave the orange section available for the subs enclosure.
This is a side view of the subs enclosure (blue) with the steel bars (black) and the wooden beams (orange)
The main objective is to have the enclosure invisible when sitting on the couch. The rear height of the subs enclosure can extend probably a little lower due to the line of sight from the seats which also increases the internal volume.
The external volume is approx. 170 liters and will put in 2 subwoofer units 12 or 15 inch operated mono in the same box volume .. still working in the final details but I will cope with that.
The internal volume will be approx. 120 litres.
One of the challenges is how to mount the encolusure ?
I could rest it on the steel frame (with spikes) but I am thinking about to screw the top of the enclosure directly to the underside of the wooden beams from inside the subwoofer box.
The beams themselves are fixed with M8 bolts to the steel frame at all 3 main stands so it is fairly rigid.
The wood burner on top adds to the total mass so I guess it should not resonate.
Also the total mass of the whole construction is considerable: total 430 kg
steel frame: 20 kg
5 wooden beams: 240 kg
stone slab under wood burner: 40 kg
wood burner: 130 kg
Are there any objections for the subwoofer performance to mount it like that ?
The whole construction stands only on the floor and is not attached to the rear wall, the neighbours should not get any clue about my upgrade
When everything is done it will still look like this ... no visible equipment and only the Boenicke W5 in the room which are nice to look at anyway
The last couple of weeks I have been preparing the subwoofer cabinet and mounting it under the wooden furniture.
As you can see the available space is limited by the 3 steel bars of 25mm square, one at the top en 2 at both sides.
See also the schematic drawing in my previous post above.
Therefore I need to build the cabinet is sections and mount them one by one.
Here are the different stages of mocking up the model:
I tried to maximise the volume by having extend the rear part of the cabinet even lower but still stay out of sight when seated on the couch due to the line of sight. The slope angle is 12 degrees.
To get it fit under and be able to connect it all together was a hell of a job.
Like working under a car without a jack.
The reinfocement bracing ready to be mounted .. the long screws fix the cabinet directly in the 15x15 cm beams of the furniture above.
This is how it is now.
The bottom plate will also be attached to the bracing with the same big screws as used for the bracing itself and the outer circumfence will be sealed with kit to get it airtight to become a sealed box.
In this panel the 2 subwoofers will be mounted which are 2x Dayton RSS315HF-4
The Dayton units will be driven mono by a 2x200W power amp (@ 4 ohm rating)
Hopefully I can play music again next weekend and have the new Lyngdorf amp set the x-over and do a Room Calibration (RoomPerfect)
Will be continued ...
As you can see the available space is limited by the 3 steel bars of 25mm square, one at the top en 2 at both sides.
See also the schematic drawing in my previous post above.
Therefore I need to build the cabinet is sections and mount them one by one.
Here are the different stages of mocking up the model:
I tried to maximise the volume by having extend the rear part of the cabinet even lower but still stay out of sight when seated on the couch due to the line of sight. The slope angle is 12 degrees.
To get it fit under and be able to connect it all together was a hell of a job.
Like working under a car without a jack.
The reinfocement bracing ready to be mounted .. the long screws fix the cabinet directly in the 15x15 cm beams of the furniture above.
This is how it is now.
The bottom plate will also be attached to the bracing with the same big screws as used for the bracing itself and the outer circumfence will be sealed with kit to get it airtight to become a sealed box.
In this panel the 2 subwoofers will be mounted which are 2x Dayton RSS315HF-4
The Dayton units will be driven mono by a 2x200W power amp (@ 4 ohm rating)
Hopefully I can play music again next weekend and have the new Lyngdorf amp set the x-over and do a Room Calibration (RoomPerfect)
Will be continued ...
what about somerhing like this
https://audioxpress.com/article/the-hideaway-tl-sub
so you can hide it under
https://audioxpress.com/article/the-hideaway-tl-sub
so you can hide it under
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Hello
I found this remark intriguing. Apologies too all for the side track, I would like to learn more as I am trying to get away from boxes. Would you please elaborate? Do these solutions sound better then say a BR? I may have incorrectly formed an assumption that the suspension provided by the box volume plays a part in driver power handling too. Is a TL one of those better sounding solutions? A tubular TL wound up in a knot or folded like packet noodles is of particular interest to me but I don’t know where to start as I don’t have any driver parameters other then size and power handling
@ OP
I must say that those pair of speakers in the pics look gorgeous. Very well proportioned and good lines. Very similar looking to something I was making. Those stands really don’t do them justice and look odds to the heavy woody ambience with the rack and speaker boxes. Would you consider a pair of subs that formed matching stands for the very nice looking speakers? I had an idea for a stand with a matching look side firing sub driver down near the floor and using that slabby plinth as the overall base. Basically swapping that skinny pipe out for a tall sub box. You can get some amazingly well developed pancake subs in the car audio industry
Thanks and regards
Randy
Regarding bass response and cabinet design....
I've found that when a woofer is in a shallow depth enclosure, and then mounted in a deeper enclosure, the deeper box allows the woofer to "reach down" and deliver far more bass into the room.
I figure that being in a shallow enclosure puts a limit on the woofer - the air inside behind the woofer is forced back against the rear of the cone, cancelling its travel to a point.
And this sort of thing happens regardless of whether it's a ported box or air-suspension/sealed.
I've found that when a woofer is in a shallow depth enclosure, and then mounted in a deeper enclosure, the deeper box allows the woofer to "reach down" and deliver far more bass into the room.
I figure that being in a shallow enclosure puts a limit on the woofer - the air inside behind the woofer is forced back against the rear of the cone, cancelling its travel to a point.
And this sort of thing happens regardless of whether it's a ported box or air-suspension/sealed.
@maxolini
The external dimensions are 130 cm wide, 59 cm deep and 18 - 28 cm heigth wich is roughly 170 liters, indeed a sealed box.
I made a detailed calculation subtracting al the additional bracings and small planks and I get a net volume of 128 liters.
With 2 subs and 2x 200W I get a fairly high SPL compared to the satellites which have a fairly low efficiency (83-85 dB@1W)
I hope with running RoomPerfect - I bought a Lyngdorf TDAI-1120 - which will shave off the peaks that the subs which are outputting so much that it will cut off the tabletop shape completely which will move the -3 dB to a lower frequency.
I did not try to build the best subwoofer possible but the best within the available space and of course it will not be perfect but substantially better than no subs at all
It is mainly for music but looking at a Netflix movie it will surely add some substance to the sound
@Randy Bassinga
I guess you are referring to the satellites ? These are Boenicke W5 from Switzerland, bought them early 2014 when Sven Boenicke still did factory-direct so then the pricing was significantly lower compared to the prices now using his dealer network.
At first there was only this variant but he later introduced the SE version with another woofer and x-over extending a little lower.
This last addition is not relevant when using extra subs
Boenicke also has stands (350 Euro) so I decided to make a concrete stand with an rod on top ... is does the job nicely and did cost me 20 Euro in total
@wiseoldtech
We will see ... I will mount the subs as close to the wall as possible having them in the less shallow part of the cabinet.
The drawing I made suggests they would be mounted more forward in the shallower part .. this is not the case.
At the centerline of the sub the cabinet will be approx. 22-23 cm deep and angled 12 degrees towards the listener.
I also need to try different amounts of damping material and when put behind the woofer it may also compensates some of the impact on the shallow restrictions ?
The external dimensions are 130 cm wide, 59 cm deep and 18 - 28 cm heigth wich is roughly 170 liters, indeed a sealed box.
I made a detailed calculation subtracting al the additional bracings and small planks and I get a net volume of 128 liters.
With 2 subs and 2x 200W I get a fairly high SPL compared to the satellites which have a fairly low efficiency (83-85 dB@1W)
I hope with running RoomPerfect - I bought a Lyngdorf TDAI-1120 - which will shave off the peaks that the subs which are outputting so much that it will cut off the tabletop shape completely which will move the -3 dB to a lower frequency.
I did not try to build the best subwoofer possible but the best within the available space and of course it will not be perfect but substantially better than no subs at all
It is mainly for music but looking at a Netflix movie it will surely add some substance to the sound
@Randy Bassinga
I guess you are referring to the satellites ? These are Boenicke W5 from Switzerland, bought them early 2014 when Sven Boenicke still did factory-direct so then the pricing was significantly lower compared to the prices now using his dealer network.
At first there was only this variant but he later introduced the SE version with another woofer and x-over extending a little lower.
This last addition is not relevant when using extra subs
Boenicke also has stands (350 Euro) so I decided to make a concrete stand with an rod on top ... is does the job nicely and did cost me 20 Euro in total
@wiseoldtech
We will see ... I will mount the subs as close to the wall as possible having them in the less shallow part of the cabinet.
The drawing I made suggests they would be mounted more forward in the shallower part .. this is not the case.
At the centerline of the sub the cabinet will be approx. 22-23 cm deep and angled 12 degrees towards the listener.
I also need to try different amounts of damping material and when put behind the woofer it may also compensates some of the impact on the shallow restrictions ?
high SPL at what freq? 100hz?
dayton recommends
OPTIMUM CABINET SIZE *
Sealed Volume 0.71 ft.³ thats around 20 liters for an F3 of 53 Hz
thats way off your 120L furniture box
you can make random wood box of wathever dimmensions and stick any available driver at hand but how it will sound is a mistery, can be fair... can be terrible ... is like shooting in the dark.