But that beyma does not go that low (same case fit with similar QTC). And i doubt it sounds as good as the SB woofer. But if budget is an issue, it can work.
On the amp, off course there are cheaper ones, but not that i would use. But many cheaper plateamps from Dayton and others exist that are decent good for this application. And seperate class D amps will probally also be cheaper. But do they fit the goal of the OP?
On the amp, off course there are cheaper ones, but not that i would use. But many cheaper plateamps from Dayton and others exist that are decent good for this application. And seperate class D amps will probally also be cheaper. But do they fit the goal of the OP?
Thanks again. I've rather come around to the idea of two drivers in their own boxes, scattered around the listening room.
A single SB SB34NRX75-6 sounds like it could shake my house down, but I can't help thinking two Beyma 12BR70 at £65 each seems pretty good value and gets me the whole two subs are better than one (and three better than two, and etc etc etc) thing and can be powered from a stereo power amp with enough juice. There seem to be a few of them about, and they're easily controlable with my DSP.
Simplicity, cheapicity, and scatterability all sound good there.
I have to ask - sorry I have very little time this weekend, corona virus wedding in central London - What do you think the Beyma could achieve in two sealed 50-60l boxes with 300-500w pushing them and a little DSP? In terms of both depth, and speed? SPL requirements are low.
That may well be more than enough for my needs.
A single SB woofer, while much more impressive on its own, vs two lesser drivers scattered about the place - that's the question.
PS... Materials costs are very little for me - so long as box sizes aren't enormous. I have an entire house full of surplus chests of drawers, closets, cupboards, and even a piano in need of a major (MAJOR) service that I can't see anyone wanting to pick up for free in the current climate. I also work on a farm where we're storing 20 old hardwood pews from the boss's church just waiting for someone to have a need for them... One or two of those could perhaps be repurposed.
Wood should be no problem, and I have all the screws and glues we could ever need.
£200-300 on drivers and amplification*, a bit of time, and I expect I'm finding where the value lives in this British DIY subwoofer world.
*I'm resigned to rack mount amplification - plate amplifiers are just too expensive, provide less flexibility, and do redundant work which my miniDSP can easily take care of. I'm even working out a way to crossover the mains and subs with some sort of pre-amp... Later down the line of course.
A single SB SB34NRX75-6 sounds like it could shake my house down, but I can't help thinking two Beyma 12BR70 at £65 each seems pretty good value and gets me the whole two subs are better than one (and three better than two, and etc etc etc) thing and can be powered from a stereo power amp with enough juice. There seem to be a few of them about, and they're easily controlable with my DSP.
Simplicity, cheapicity, and scatterability all sound good there.
I have to ask - sorry I have very little time this weekend, corona virus wedding in central London - What do you think the Beyma could achieve in two sealed 50-60l boxes with 300-500w pushing them and a little DSP? In terms of both depth, and speed? SPL requirements are low.
That may well be more than enough for my needs.
A single SB woofer, while much more impressive on its own, vs two lesser drivers scattered about the place - that's the question.
PS... Materials costs are very little for me - so long as box sizes aren't enormous. I have an entire house full of surplus chests of drawers, closets, cupboards, and even a piano in need of a major (MAJOR) service that I can't see anyone wanting to pick up for free in the current climate. I also work on a farm where we're storing 20 old hardwood pews from the boss's church just waiting for someone to have a need for them... One or two of those could perhaps be repurposed.
Wood should be no problem, and I have all the screws and glues we could ever need.
£200-300 on drivers and amplification*, a bit of time, and I expect I'm finding where the value lives in this British DIY subwoofer world.
*I'm resigned to rack mount amplification - plate amplifiers are just too expensive, provide less flexibility, and do redundant work which my miniDSP can easily take care of. I'm even working out a way to crossover the mains and subs with some sort of pre-amp... Later down the line of course.
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Okay, let's do a quick and dirty comparison on small/compact subs. For simplicity I will set the box volume to 60 liters for all designs. 12" and up will have to use closed boxes, since the volume is really too small for any vented designs for large membrane drivers. Just threw in the Beyma 8BR40/N (38£ each!) as a low-cost, mid-xmax, very cheap comparison.
The 15" Beyma SM-115/N costs 100£ on bluearan, not that I'm in love with Beyma or anything. They're just very good options if you're sorting by price and looking for decent quality cast-frame drivers, while glancing at parameters like FS and qts. Very good value for the money.
I think you'd be happy with a couple 12BR70 jjams.
The 15" Beyma SM-115/N costs 100£ on bluearan, not that I'm in love with Beyma or anything. They're just very good options if you're sorting by price and looking for decent quality cast-frame drivers, while glancing at parameters like FS and qts. Very good value for the money.
I think you'd be happy with a couple 12BR70 jjams.
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for about £250 used you can get a P7000s that is silent (fan does not spin in normal use) that will do 2000W into 8ohm or 2*1000W into 4 ohm. See my thread on quiet PA amps:
Quiet PA amps
there are some basic tests at the end.
I can't read that picture as the resolution is to low.
But for the record, i simmed the SB i mentioned in a 60L case wit an 100W power amp and the Beyma in identical conditions, so you can compare. The Beyma is slightly more efficient and sounds good, the SB goes lower and sounds better. The choice is yours...
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Even after clicking "expand to actual size"?
Jpeg compression blurs it a little bit, but other than that it reads just fine here.
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I don't have that option, maybe it's my browser (Google Chrome) that i use for surfing. IE is configured to stay offline for my job on this computer (only intranet connection) for security reasons... But when i download the file i can see it. And again the SB looks the best for me on how low it goes (the main factor for the OP i thought).
Wow, lots to think about, and a lot of work done to help me out with this. I appreciate the time put into these calcs. I suspect it's time to think, compare, model, and think some more. I won't rush into anything.
I reckon i've got all i need to figure this out now...
I'm still regularly surprised by how good the remaining Trad forums are. Many thanks everyone
I reckon i've got all i need to figure this out now...
I'm still regularly surprised by how good the remaining Trad forums are. Many thanks everyone
IMO It's not much to think about really, the SB driver costs the same as two 12BR70's. Sound quality should be very compareable.
I made a video of my daughters 12BR70 TQWT's today, will see if I can get around to editing a bit if you're interested. No measurements ATM, but they're powered by a cheap TPA3255 ebay amp and a brick PSU, I estimate some of the quite bass heavy music I tested with was well above 100db, probably around 108db if my estimations still work.
The simulations I posted was for halfspace, so you should get better than that indoors, I don't like to give over-optimistic numbers.
I agree! This forum is great!
I made a video of my daughters 12BR70 TQWT's today, will see if I can get around to editing a bit if you're interested. No measurements ATM, but they're powered by a cheap TPA3255 ebay amp and a brick PSU, I estimate some of the quite bass heavy music I tested with was well above 100db, probably around 108db if my estimations still work.
The simulations I posted was for halfspace, so you should get better than that indoors, I don't like to give over-optimistic numbers.
I agree! This forum is great!
I've just started having a look at the videos, but when I'm pushin them a bit the mic distorts.
The video sound is not horrible, but there seems to be some compression kicking in at some point, makes it sound more muddy and the top end and mids are lacking a fair bit because of it. In real life it sounds real crisp and clean, no distortion whatsoever.
Another thing to note is that these boxes are twice the size of what you're looking at, and you'll get a bit more excursion since you don't get the acoustic resonance of ported designs. But in these boxes my daughter have, the 12BR70's never really get to "stretch their legs" at all. She's a real bass head, don't know where she get's it from. But I guess we've all been there at some point.
Here ya go:
YouTube
The video sound is not horrible, but there seems to be some compression kicking in at some point, makes it sound more muddy and the top end and mids are lacking a fair bit because of it. In real life it sounds real crisp and clean, no distortion whatsoever.
Another thing to note is that these boxes are twice the size of what you're looking at, and you'll get a bit more excursion since you don't get the acoustic resonance of ported designs. But in these boxes my daughter have, the 12BR70's never really get to "stretch their legs" at all. She's a real bass head, don't know where she get's it from. But I guess we've all been there at some point.
Here ya go:
YouTube
A reliable 20Hz is going to require at least 2 12" woofers or a good 15. A Dayton Ultimax 15 through Amazon UK is about 300GBP with shipping (shipping from NL). A nice vented cabinet should be another 100-150 (~2cm-thick MDF, bracing, and a pair of flared ports), but it'll *definitely* get you to 20Hz. You'll just need an active crossover to blend into the mains. It'll definitely blow anything similarly priced out of the water in terms of bottom-end heft. Only problem is, you're looking at a much larger box (think 170L, ~63cmx60cmx45cm). With a 15Hz subsonic filter, you can achieve a maximum output of about 110dB (1 meter distance) at 20Hz, with 115dB at 30Hz before hitting XMax (this is on 550W of power).
It might sound like overkill in terms of output, but a 15" woofer will have far less distortion due to the larger surface area and lower excursion relative to a smaller cone (at the same output level).
It might sound like overkill in terms of output, but a 15" woofer will have far less distortion due to the larger surface area and lower excursion relative to a smaller cone (at the same output level).
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Alekk As much as I love the idea, the room is to small for that and I don't need much in the way of levels, neighbours... They're good as far as neighbours go, but I don't want to push it with a reliable 20Hz in a 6x4m (total guess) bedroom that adjoins their house. A reliable 25-30Hz will cause enough trouble as it is, much bass chaos to be tamed. Many thanks anyway though.
KaffiMann Power is back! Ahh, the joys of living semi-countryside. Thanks very very much for that!! Took a bit of setup and editing! When you wrote "going for the drum&bass version" I thought "yes!! Perfect!!". Shame it scared away the boss though - but hey, you got good kids there if they enjoy a setup like that.
The last tune sealed it for me. They do the job! Thanks for your effort there, I really appreciate it
KaffiMann Power is back! Ahh, the joys of living semi-countryside. Thanks very very much for that!! Took a bit of setup and editing! When you wrote "going for the drum&bass version" I thought "yes!! Perfect!!". Shame it scared away the boss though - but hey, you got good kids there if they enjoy a setup like that.
The last tune sealed it for me. They do the job! Thanks for your effort there, I really appreciate it
I got a very similar speaker system, Mark Audio Alpair 10M sealed tops but 10 Scanspeak 26W/8534G00 subs in sealed speakers and they give me everything i need. The subs are smaller altough, only 77L and with an good response (F6) of 32Hz. But i use a passive crossover and a tube amp with it. Not dsp and a chipamp.
And i listen partly to very similar music, reggae, dub, jungle & co... but i'm also a jazz freak and listen to a lot of other music also. Your daughter is spoiled with that setup...
I'm starting to go about this backwards, and buy an amp.
Thing I like about this A800 is that it it's convection cooled - no bloody fan making noise!
Any other no-fan sub amps in this price range I should be thinking about?
Kip has a thread on quiet amps over in the PA subforum, if you haven't seen it already: Quiet PA amps.