Hi,
I will shortly be building a pair of Jeff Bagby's Spirit Wind 2 way monitors - these use the Audio Technology 18H mid/bass driver.
I'm going to extend their response with subs, but cannot decide on what would work best in my 5m by 5m room (which I understand is the worst shape!).
The sub's would be sealed and use NCore plate amps, or multichannel power amp plus DSPmini, to do a linkwitz transform (if necessary) to extend the frequency response if needed. I'm targeting flat down to 30Hz at 90dB.
Option 1: Pair of subs acting as stands for the monitors (Like Jeff's Kairos 3 ways), but using the Audio Technology Flexunits 10" or 12" driver - these drivers are quite expensive! Also I don't know if they'd be a good match for a sealed sub?
Option 2: Same as above, but using either SB acoustics 12" sb34nrx75-6 or 15” SB42FHC75-6, Dayton Audio RSS315HFA-8 12" Reference HF or RSS460HO-4 18".
Option 3: Multichannel power amp and four subs using cheaper Dayton audio RSS265HF-8 10" Reference HF. But enclosures would have to be smaller I guess.
What would likely be the 'better' solution? I'm aiming for low group delay, fast transient response and a dynamic sound.
I am presuming that larger Sd is always better!
I will shortly be building a pair of Jeff Bagby's Spirit Wind 2 way monitors - these use the Audio Technology 18H mid/bass driver.
I'm going to extend their response with subs, but cannot decide on what would work best in my 5m by 5m room (which I understand is the worst shape!).
The sub's would be sealed and use NCore plate amps, or multichannel power amp plus DSPmini, to do a linkwitz transform (if necessary) to extend the frequency response if needed. I'm targeting flat down to 30Hz at 90dB.
Option 1: Pair of subs acting as stands for the monitors (Like Jeff's Kairos 3 ways), but using the Audio Technology Flexunits 10" or 12" driver - these drivers are quite expensive! Also I don't know if they'd be a good match for a sealed sub?
Option 2: Same as above, but using either SB acoustics 12" sb34nrx75-6 or 15” SB42FHC75-6, Dayton Audio RSS315HFA-8 12" Reference HF or RSS460HO-4 18".
Option 3: Multichannel power amp and four subs using cheaper Dayton audio RSS265HF-8 10" Reference HF. But enclosures would have to be smaller I guess.
What would likely be the 'better' solution? I'm aiming for low group delay, fast transient response and a dynamic sound.
I am presuming that larger Sd is always better!
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Use RSS265HO-4 driver as most suitable for subwoofer of your preference by a fair margin (do not ask why at this stage), then mix 2nd and 3rd option building compact subwoofers pair as stands for monitor and another identical pair of subwoofers placed at the opposite side of the room, at your back. Another best 10" drivers available for this kind of installation are Peerless XLS10 (P830452) and Seas L26R4OY. You will need to do Linkwitz-transform on the DSP but it is perfectly normal.
Then apply delays to either front or back pair of subwoofers (in case of front pair, obviously delay all three ways) which is equal to the distance between front and back subwoofers. Additionally, try flipping the phase of pair at your back.
Experimentally find best bass response which is characteristic to your particular room and your listening place, but of course you can evaluate it in measurements using cheap UMIK-1 USB mic and REW software which is free.
Then apply delays to either front or back pair of subwoofers (in case of front pair, obviously delay all three ways) which is equal to the distance between front and back subwoofers. Additionally, try flipping the phase of pair at your back.
Experimentally find best bass response which is characteristic to your particular room and your listening place, but of course you can evaluate it in measurements using cheap UMIK-1 USB mic and REW software which is free.
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RSS265HO-4 is definitely the best choice - thanks for pointing it out to me.
I also had another nice idea - having 4 smaller subs also provides for the possibility of a stacked pair under each of the monitors as well as the likely better option of placement 2 front and 2 rear - so allows some good flex with placement.
Many thanks once again - nice to have feedback on ideas. I'll post some feedback on build once it occurs (I have the drivers for the Spirit Winds, just need to start building).
I also had another nice idea - having 4 smaller subs also provides for the possibility of a stacked pair under each of the monitors as well as the likely better option of placement 2 front and 2 rear - so allows some good flex with placement.
Many thanks once again - nice to have feedback on ideas. I'll post some feedback on build once it occurs (I have the drivers for the Spirit Winds, just need to start building).
It is possible to use REW room mode simulator which can loosely estimate room mode suppression via 4 identical LF devices before even you build it. Remember, REW results are only estimation, not simulation and real-life results are often slightly different by all means.
Another possibility is to use random subwoofers placement and Multi Sub Optimizer software. Having compact subwoofers is always convenient from this point of view. From my memory, best sound was obtained everytime when one pair of LF extensions was placing close to monitors, creating 3 way stack. Hiding subwoofers under sofa caused seat to vibrate what is not welcome behaviour in music (but in HT - yes!).
Another possibility is to use random subwoofers placement and Multi Sub Optimizer software. Having compact subwoofers is always convenient from this point of view. From my memory, best sound was obtained everytime when one pair of LF extensions was placing close to monitors, creating 3 way stack. Hiding subwoofers under sofa caused seat to vibrate what is not welcome behaviour in music (but in HT - yes!).
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Hi!
Stretchneck, this link may prove to be useful to you:
Tuning multiple subs
Also, I posted a step by step recommendation here:
Budget subwoofer 'swarm'?
Best,
Anand.
Stretchneck, this link may prove to be useful to you:
Tuning multiple subs
Also, I posted a step by step recommendation here:
Budget subwoofer 'swarm'?
Best,
Anand.
Hi,
So have been reading the provided information. REW room mode simulator seems to suggest that a single sub-woofer placed exactly in the middle of the front wall would be best. Multi-sub does provide smoothing of response depending upon listening position, but the benefit appears to be otherwise minimal?
Really glad that REW room mode simulator was suggested to me - but REW would suggest that a single sub is best?... Seems that a square room is a pain!
So have been reading the provided information. REW room mode simulator seems to suggest that a single sub-woofer placed exactly in the middle of the front wall would be best. Multi-sub does provide smoothing of response depending upon listening position, but the benefit appears to be otherwise minimal?
Really glad that REW room mode simulator was suggested to me - but REW would suggest that a single sub is best?... Seems that a square room is a pain!
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Exactly in the middle of 2 walls is going to create big nulls or cancellations, everywhere in the room.
option 3 Multiple mono sealed small subs not to far apart ( <1/4 wavelength in theory) from each other, near your tops and near corners or at least against walls sounds best to me. If you have more then 2 it's worth to elevate 1 or more.
1: phi (golden ratio) or about 5:8 is best to use when placing speakers, especially for your tops.
If your speakers are closer to the ceiling then the floor (and should also not be half way) then hanging the subs at the ceiling also makes sense. Often not very practical, but best to do with small sealed subs because of their size and weight.
IMO sealed sounds best by far and smaller rooms compensate for the roll off and if needed a little lows boost is fine to use.
Don't EQ the life/feel out of it.
option 3 Multiple mono sealed small subs not to far apart ( <1/4 wavelength in theory) from each other, near your tops and near corners or at least against walls sounds best to me. If you have more then 2 it's worth to elevate 1 or more.
1: phi (golden ratio) or about 5:8 is best to use when placing speakers, especially for your tops.
If your speakers are closer to the ceiling then the floor (and should also not be half way) then hanging the subs at the ceiling also makes sense. Often not very practical, but best to do with small sealed subs because of their size and weight.
IMO sealed sounds best by far and smaller rooms compensate for the roll off and if needed a little lows boost is fine to use.
Don't EQ the life/feel out of it.
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Thanks Think - yes you're right large nulls in the middle of the room.
Trouble is, even trying different configs (2,3 or 4 subs) as you suggest REW still predicts a complete dearth of bass in middle of the room - I just can't seem to find any locations in a 5x5m square room using different configs of subs that yields a flat frequency response.
Shame REW can't model dipole subs.
If anyone can show me a modelled answer in REW I'd be grateful.
Trouble is, even trying different configs (2,3 or 4 subs) as you suggest REW still predicts a complete dearth of bass in middle of the room - I just can't seem to find any locations in a 5x5m square room using different configs of subs that yields a flat frequency response.
Shame REW can't model dipole subs.
If anyone can show me a modelled answer in REW I'd be grateful.
Attachments
Another option for you could be to use this driver as your in the UK and its very cheap:
Thompsons Ltd | Pyle PLPW15D 15" Inch 2000w Car Audio Subwoofer Driver Sub Bass Speaker Woofer
I have 12 of them in sealed boxes and use a DSP amplifier to EQ them flat to 20Hz. You need about 50L minimum per driver.
YupI've managed to place my 2 U frames to give smooth response, 4 subs for the price of 2
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