...hmm, not sure why my Photobucket pics didn't post?
**edit** problem solved
**edit** problem solved
Sunfire/Boston Acoustics Frankenstein Experiment
6
Hi all,
I've never really though about building my own home sub until the last couple of weeks ( looking at some of the builds here really propelled me in that direction ) The biggest motivator was the voice coil coming apart from the spider in my Sunfire MKII sub..a real downer. I was going to buy another driver, and that got vetoed by my better half, so I thought about sending my current driver out for repair but couldn't decide.
I have a Boston SPG555 car subwoofer in 1cu/ft, 3/4"MDF sealed enclosure, that I built in a hurry without any care other than it was sealed well ( read: it's ugly :dumbcrazy
. This sub was pretty impressive when I had it in my car, it was the best sub that I had owned after owning a multitude of car subs from my younger days..I really did forget just how impressive:R
It will handle 1000w RMS, and as mentioned, fits in a 1 cu/ft sealed box, and has more surface area than a 12" sub.I really wish I had the know-how to use the specs in the manual to custom design a box for this particular build. Since I don't, I though I would experiment with whatever I currently have at my disposal. Here is the sub:
![]()
![]()
![]()
I decided to hook up the Sunfire amp to the Boston sub, I was a little worried at first because of what I'd read about the circuitry in the amp/crossover/voice coil work together utilizing the high back EMF of the Sunfire woofer's monster magnet. The boston has a large neodymium magnet, and so I thought 'why not ?':scratch:
..and I tried it:bigsmile: At first at low to medium volume, and soon enough, I turned it up. I was pretty shocked with the result, it was louder and tighter than the MKII..unfortunately, I now have a few annoying vibrations in my room that this sub brought out:R . In fact, some music that never sounded right with the MKII ( Tupac, some metal music ) all of a sudden sound great, and the speed of a fast kick drum in metal music has never hit so hard and fast as it does now. I really loved my MKII, and didn't want to ever part with it, now I'm rethinking that idea.
Well yesterday, I had the day off and decided to try phase 2 of this experiment. I took the passive radiator out of the Sunfire, and put it on the opposite side of the boston. I was a little worried that this may be taking things too far, because I really don't know anything about designing a sub box, especially one with a round passive radiator on an oval sub:coocoo: ( if somebody is willing to help with this, please post here ). I also lack tools/space to build a decent enclosure.
![]()
![]()
Here's the MKII beside the ugly block:
![]()
After trying it, it appears to be a good move. I don't have a db meter or test equipment ( yet ), so I used the db meter on my iPhone, and I gained just over 3db on my phone:scratch: It also seems to play lower frequencies louder than just a sealed box( not sure if this box is still considered sealed ? ) Yet it's still tight.
The sub amp volume is turned down lower than before( a couple notches lower than midpoint ) but the thing seems louder than ever before, and my room has less nulls, where before, the bass relied heavily on proper placement because my room has a strange ceiling design. I decided not to fix the Sunfire, and instead build a nice enclosure for my Frankenstein setup instead. The only lingering question, can someone design an enclosure that would better exploit the full potential of my equipment ? I'm sure there is, and I hope they aren't shy about posting, you're help will be appreciated.
I've never really though about building my own home sub until the last couple of weeks ( looking at some of the builds here really propelled me in that direction ) The biggest motivator was the voice coil coming apart from the spider in my Sunfire MKII sub..a real downer. I was going to buy another driver, and that got vetoed by my better half, so I thought about sending my current driver out for repair but couldn't decide.
I have a Boston SPG555 car subwoofer in 1cu/ft, 3/4"MDF sealed enclosure, that I built in a hurry without any care other than it was sealed well ( read: it's ugly :dumbcrazy
. This sub was pretty impressive when I had it in my car, it was the best sub that I had owned after owning a multitude of car subs from my younger days..I really did forget just how impressive:RIt will handle 1000w RMS, and as mentioned, fits in a 1 cu/ft sealed box, and has more surface area than a 12" sub.I really wish I had the know-how to use the specs in the manual to custom design a box for this particular build. Since I don't, I though I would experiment with whatever I currently have at my disposal. Here is the sub:
I decided to hook up the Sunfire amp to the Boston sub, I was a little worried at first because of what I'd read about the circuitry in the amp/crossover/voice coil work together utilizing the high back EMF of the Sunfire woofer's monster magnet. The boston has a large neodymium magnet, and so I thought 'why not ?':scratch:
..and I tried it:bigsmile: At first at low to medium volume, and soon enough, I turned it up. I was pretty shocked with the result, it was louder and tighter than the MKII..unfortunately, I now have a few annoying vibrations in my room that this sub brought out:R . In fact, some music that never sounded right with the MKII ( Tupac, some metal music ) all of a sudden sound great, and the speed of a fast kick drum in metal music has never hit so hard and fast as it does now. I really loved my MKII, and didn't want to ever part with it, now I'm rethinking that idea.
Well yesterday, I had the day off and decided to try phase 2 of this experiment. I took the passive radiator out of the Sunfire, and put it on the opposite side of the boston. I was a little worried that this may be taking things too far, because I really don't know anything about designing a sub box, especially one with a round passive radiator on an oval sub:coocoo: ( if somebody is willing to help with this, please post here ). I also lack tools/space to build a decent enclosure.
Here's the MKII beside the ugly block:
After trying it, it appears to be a good move. I don't have a db meter or test equipment ( yet ), so I used the db meter on my iPhone, and I gained just over 3db on my phone:scratch: It also seems to play lower frequencies louder than just a sealed box( not sure if this box is still considered sealed ? ) Yet it's still tight.
The sub amp volume is turned down lower than before( a couple notches lower than midpoint ) but the thing seems louder than ever before, and my room has less nulls, where before, the bass relied heavily on proper placement because my room has a strange ceiling design. I decided not to fix the Sunfire, and instead build a nice enclosure for my Frankenstein setup instead. The only lingering question, can someone design an enclosure that would better exploit the full potential of my equipment ? I'm sure there is, and I hope they aren't shy about posting, you're help will be appreciated.
1 - 20 of 36 Posts
Oh it's done, it's not pretty, but it's done.
At first I was really disappointed. So I read some more and realized I'd tuned it too low, opened the box back up, trimmed off a foot from each of the four ports, sealed it back up and voila lovely house shaking bass with both music and movies. Mind you my room isn't that big so that might have something to do with it
I'm using one channel on a Behringer EP2500 turned up about three quarters on it's dial and subwoofer set to 0 on my Yamaha RX-V1800.
I have to leave it there for movies but can crank both to max for all but the bassiest(I know not a real word eh?) of Dubstep. It's a RFD2112 which is rated at 500/1000 that I picked up used at a pawn shop for $45.00. The manual for the Behringer lists it's output at 1200W which is probably peak.
You can see the open box (with the longer ports) in my picture.
As for WAF, we are living with the ugly brown box until the nice weather returns and I can build something nicer.
At first I was really disappointed. So I read some more and realized I'd tuned it too low, opened the box back up, trimmed off a foot from each of the four ports, sealed it back up and voila lovely house shaking bass with both music and movies. Mind you my room isn't that big so that might have something to do with it
I'm using one channel on a Behringer EP2500 turned up about three quarters on it's dial and subwoofer set to 0 on my Yamaha RX-V1800.
I have to leave it there for movies but can crank both to max for all but the bassiest(I know not a real word eh?) of Dubstep. It's a RFD2112 which is rated at 500/1000 that I picked up used at a pawn shop for $45.00. The manual for the Behringer lists it's output at 1200W which is probably peak.
You can see the open box (with the longer ports) in my picture.
As for WAF, we are living with the ugly brown box until the nice weather returns and I can build something nicer.
3
Well my friend, I want to thank you once again for all of your help! Today this arrived:
It took a while because it had to come from Japan before it was shipped out to me. I still can't believe that I was finally able to get the radiators, and could not have done it without you ( I gave up a long time ago ). I had to go by the wood shop to tell the guy building the box that the hole for the radiator has to change. I can't wait until the box is finished.
1 - 20 of 36 Posts
