My main listening setup is a pair of KEF 104ab's that I dearly love (I dropped less than $3 with tax for the pair at a thrift store, which helps me like them even more) I really enjoy the way they sound, especially the sparkle they have up high, but I wish they dug a bit deeper sometimes (I feel like they die out around 45-50Hz). They are set up in the living room, and have an incredibly high WAF. The teak cabinets and "futuristic" driver layout blends so well with our our mid-century/danish modern decor that she actually likes them. She doesn't understand why they sit so far away from the walls, but doesn't seem to mind. I consider myself incredibly lucky that I can have some decent sized speakers prominently placed in our main living space that my other half approves of.
Neither of us are pleased with the aesthetics of the amp setup, so I am building a credenza/sideboard/media center that can hold amps and will have some space for books, plants, bits and bobs etc. While I'm making something custom, I've been toying around with adding a small sub into the design.
My current plans either have a chamber that is 2.9cu ft (80-ish liters) that is slightly off center, or a chamber that is 1.9 cu ft (55 liters) that would be dead center of the room. Two ~1.2 cu ft chambers, one on each side of the cabinet are a possibility also, though I haven't sketched this option out yet. I don't think any of these proposed chambers are large enough to accommodate a properly sized port, especially once I subtract driver volume, I think I'll have to go sealed.
This is a music only system that doesn't see particularly high SPL's, and I don't expect to feel kick drum in my chest out of this setup. I can only budget about $100 for drivers (Thankfully I have a beefy plate amp on hand already). I'm looking at a 12" Dayton, probably the DVC, but I can physically fit a 15" but I think I run into the small volume problem with any 15" I can get within my budget.
Admittedly, my only real experience with subs is within a HT setup where space has not been an issue, so it's always been 15's in a reflex or IB configuration. I'm just a bit timid about a 12" in a acoustic suspension enclosure - so small... so sealed
I'm also a bit concerned about how well a sub will integrate with my existing setup - I do enjoy how clean my system sounds and don't want to go to the extra expense and work just to muck that up.
I know you can't tall me what I will be happy with, but what do you think about my situation? Any concerns or pitfalls I seem to be overlooking? Any suggestions? Should I just scrap the whole idea, or is it worth a try?
Neither of us are pleased with the aesthetics of the amp setup, so I am building a credenza/sideboard/media center that can hold amps and will have some space for books, plants, bits and bobs etc. While I'm making something custom, I've been toying around with adding a small sub into the design.
My current plans either have a chamber that is 2.9cu ft (80-ish liters) that is slightly off center, or a chamber that is 1.9 cu ft (55 liters) that would be dead center of the room. Two ~1.2 cu ft chambers, one on each side of the cabinet are a possibility also, though I haven't sketched this option out yet. I don't think any of these proposed chambers are large enough to accommodate a properly sized port, especially once I subtract driver volume, I think I'll have to go sealed.
This is a music only system that doesn't see particularly high SPL's, and I don't expect to feel kick drum in my chest out of this setup. I can only budget about $100 for drivers (Thankfully I have a beefy plate amp on hand already). I'm looking at a 12" Dayton, probably the DVC, but I can physically fit a 15" but I think I run into the small volume problem with any 15" I can get within my budget.
Admittedly, my only real experience with subs is within a HT setup where space has not been an issue, so it's always been 15's in a reflex or IB configuration. I'm just a bit timid about a 12" in a acoustic suspension enclosure - so small... so sealed
I'm also a bit concerned about how well a sub will integrate with my existing setup - I do enjoy how clean my system sounds and don't want to go to the extra expense and work just to muck that up. I know you can't tall me what I will be happy with, but what do you think about my situation? Any concerns or pitfalls I seem to be overlooking? Any suggestions? Should I just scrap the whole idea, or is it worth a try?
A couple of things having owned small KEF speakers myself
Yes they need subwoofers but I would think that if you could get a pair of the old racetrack woofers that they would be perfect
Although I am still unsure about the sonic benefits of particular speaker materials in the make of of a driver being all that important in s a subwoofer.
A pair of 12 inch woofers in small sealed boxes would be the way to proceed. Can you split the feed from the Dayton plate amplifier to 2 separate speakers?
A small separate enclosure for the amp perhaps? There is a small Dayton woofer I really like that should work
I was playing with it this morning as I have a quad of them on hand for a frugalphile project
55 watts in a 35 litre sealed box looks reasonable although I would stuff with FG as a matter of course
Yes they need subwoofers but I would think that if you could get a pair of the old racetrack woofers that they would be perfect
Although I am still unsure about the sonic benefits of particular speaker materials in the make of of a driver being all that important in s a subwoofer.
A pair of 12 inch woofers in small sealed boxes would be the way to proceed. Can you split the feed from the Dayton plate amplifier to 2 separate speakers?
A small separate enclosure for the amp perhaps? There is a small Dayton woofer I really like that should work
I was playing with it this morning as I have a quad of them on hand for a frugalphile project
55 watts in a 35 litre sealed box looks reasonable although I would stuff with FG as a matter of course
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When it comes to building subwoofers into furniture, I think the only sensible option is to go for opposed drivers. Take a look at the B&W PV1 to get an idea.
With that driver arrangement, the cones are always moving in opposite directions, which means a reasonably sturdy cabinet will have zero vibration since all the forces cancel out. That's really important for if you happen to have a turntable (mine is sat on top of a pair of long-throw 12"s, zero issues) or other vibration-sensitive equipment (CD player, even amplifiers to a lesser extent) sat on top.
Taking the idea of 2x smaller enclosures at each end of the unit, I'd go for 2x10"s per side. You can mount them firing front and back, or out the sides.
I tested my setup by disconnecting one of the drivers, and found the turntable itself started to rattle at a fairly low volume. Connect the second driver up again, and it's the windows upstairs that rattle.
To get the sub(s) integrated, I'd recommend having some DSP on-hand, and getting hold of a measurement system. Rooms do terrible things at low frequencies. With my current setup, my main speakers have a room-related peak at 45Hz. What I've done is brought the sub in around there, and played with delays until the sub and speakers cancel each other out a little, which has reduced the 45Hz peak right down to flat. It was a bit of work, but worth it - integration is now pretty much seemless.
Measurement setups are one of those things where it's pretty expensive if you only use it once. If you use it for 10 projects, though, it ends up a small fraction of the cost of each project. My only regret is not buying mine sooner.
Chris
My friend had them for several years so I know 104ab. There should be no shortage of low frequencies with them. I would not recommend subwoofer for the loudspeakers of that size . They are far from small loudspeakers. But I noticed that you keep them away from the walls. All you have to do is to put them nearer to wall(s). Move them 10 centimeters closer to walls until you get the right response. Try to move them closer to rear wall than to corners.
When I say "so far away from the walls", I mean my SO doesn't understand why they aren't tucked into the corners, touching the walls
I've worked with placement quite a bit, and they seem happiest about 15cm away from the back wall, and about 40 cm from the side walls too close to the sides and the imaging was... weird.Moondog, it looks like I could achieve what I want with 12's, but I think I'm going to leave "good enough" alone (maybe play with placement some more) I'm getting the feeling that it's going to be more trouble than it's worth for a system that already sounds great. Can't blame a guy for wanting it to sound greater though.
chris661 - you raise a couple of very valid points. I hadn't considered the vibration effects on a cabinet with equipment in it - even solid state gear doesn't like to be jostled constantly, something I will keep in mind for the future. DSP would probably help my existing system and you've helped reinforce the idea that I need to learn more about it and invest in some - it's becoming more affordable these days, and measurement isn't quite the investment it once was either
TBH I really don't like the idea of speakers built into furniture in the first place - it really limits the placement of that item. One of the reasons I'm scrapping this project is I will have so little leeway with placement, and I feel like when a sub needs to be moved. it needs more than a couple of cm left or right which is all the movement I'd really have on a piece that should sit dead-center in the room.
Thanks for the help all
I know the 104ab pretty well, was a KEF dealer in the days when these were current. DSP won't get you much, below PR tuning, the woofer "unloads", and just flops around. If you need to go deeper, sub is your answer.
I had a sub with two of the KEF B139 in it, and it sounded very good, but... In a larger room, they hit bottom much too easily. Replaced them with a table containing 4 12" subs. No, sorry, 20 years ago, I don't have the model. These worked very, very well. Today, I use 4 10", and find that even if the large room we have, they work very well.
I had a sub with two of the KEF B139 in it, and it sounded very good, but... In a larger room, they hit bottom much too easily. Replaced them with a table containing 4 12" subs. No, sorry, 20 years ago, I don't have the model. These worked very, very well. Today, I use 4 10", and find that even if the large room we have, they work very well.
Oh no, most definitely not to go deeper. I know that PR/reflex systems don't work well below their tuning frequency. I learned that the bass knob wasn't really my friend when I made my first subwoofer.
I really just want to have some fun learning something new. Plus: more gear.
Used to sell Kef 104ab back in the day.Very highly rated at the time.Should think no probs with using a sub.Personally I find the performance of most speakers improves when relived of low bass duty. At the time however the 104abs own bass was considered more than good enough.Times change eh ???BTW they were reccomended for use on stands not on the floor.
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