Nice baffleless build chromenuts!
And thanks for your words of caution!
I have been very careful not to EQ below their FS as I know this is a big 'no-no' and getting bass below 30hz in this way is not very realistic - but I will definitely watch out for this.
Also the high QTS of 0.6 helps with minimising the EQ required.
As I am using car subs - they aren't too expensive and are incredibly 'over built' - I guess to survive the world of competitive car sub bass competitions!
However it is early days, and I will watch them closely for this.
And thanks for your words of caution!
I have been very careful not to EQ below their FS as I know this is a big 'no-no' and getting bass below 30hz in this way is not very realistic - but I will definitely watch out for this.
Also the high QTS of 0.6 helps with minimising the EQ required.
As I am using car subs - they aren't too expensive and are incredibly 'over built' - I guess to survive the world of competitive car sub bass competitions!
However it is early days, and I will watch them closely for this.
Hi Zvu - I have actually already done exactly this - see the first photo of this thread - the two 'tubes' are 10" subs in push-push force cancelling configuration.
This is excellent for sealed subwoofers, but I believe will not give the figure of 8 dipole bass, as it is essentially two monopole subs placed back to back - and therefore behaves as a single monopole sub due to the wavelengths.
Hope this makes sense - the currently clamshell configuration provides true dipole bass power response.
>the currently clamshell configuration provides true dipole bass power response.
I wonder if you could merge an H frame with your 6 Hz "hammock" using an elastic sheet to separate? Get a little physical distance between the push and pull side, still maintain the dipole response.
Looks like fun and I enjoyed reading your perception of how it sounds!
I wonder if you could merge an H frame with your 6 Hz "hammock" using an elastic sheet to separate? Get a little physical distance between the push and pull side, still maintain the dipole response.
Looks like fun and I enjoyed reading your perception of how it sounds!
I think you are right - but then I have to consider why.
If I wanted more bass output - I would probably convert it to H-baffles - two of these monsters on H-baffles would give insane bass, but then I would need good sized baffles to make a decent difference.
The speakers at present are only a little over the 15" wide drivers, and space is it at a premium in my man cave
Currently I have no issues with bass volume or quantity and the whole reason I tried the clamshell configuration was to save space and reduce size.
I figure after lots more measuring and experimentation I will come to some conclusions - at present I have room shaking bass from the four 15" beasts.
If I wanted more bass output - I would probably convert it to H-baffles - two of these monsters on H-baffles would give insane bass, but then I would need good sized baffles to make a decent difference.
The speakers at present are only a little over the 15" wide drivers, and space is it at a premium in my man cave
Currently I have no issues with bass volume or quantity and the whole reason I tried the clamshell configuration was to save space and reduce size.
I figure after lots more measuring and experimentation I will come to some conclusions - at present I have room shaking bass from the four 15" beasts.
Ditto...more so with 18s
I found the aesthetics less than ideal, but compromises are inescapable
I’d like to give it another try.
The straps didn’t move at all on my set up.
Most other versions of this design that I have seen used some sort of braided steel cable to support the drivers by the magnets...I can’t speak to their use.
I believe Vic from Trans Fi said he managed to get the speakers to start moving by sending a 5Hz signal through them?
I really chose the lazy engineers approach to suspending my drivers. I found tow straps at Harbor Freight that were supposed to be 24” long...in reality I think they were more like 28”. They were $5 each and were rated for something like 1500lbs.
My speakers were about 100lbs once they were bolted together and suspended. It was quite a job getting them suspended.
I’m sure if you really tried you could get them some how to resonate, but I doubt it would be easy or done with a frequency that would have any relevance to us during listening.
Most other versions of this design that I have seen used some sort of braided steel cable to support the drivers by the magnets...I can’t speak to their use.
I believe Vic from Trans Fi said he managed to get the speakers to start moving by sending a 5Hz signal through them?
I really chose the lazy engineers approach to suspending my drivers. I found tow straps at Harbor Freight that were supposed to be 24” long...in reality I think they were more like 28”. They were $5 each and were rated for something like 1500lbs.
My speakers were about 100lbs once they were bolted together and suspended. It was quite a job getting them suspended.
I’m sure if you really tried you could get them some how to resonate, but I doubt it would be easy or done with a frequency that would have any relevance to us during listening.
Shockingly little movement. In fact non at all. The cones are going mad, but the clamshell doesn't shift and there is no palpable vibrations at all in the speaker baffle.
I got the idea for the hammocks after watching this video using the same set up.
No-Baffle DIY speaker system Pt 1 - YouTube
Speakers are these:
Avatar SST-2515D2/D4 - 15 inch Subwoofer
Cheap but good value and so far low distortion and values are as advertised.
I got the idea for the hammocks after watching this video using the same set up.
No-Baffle DIY speaker system Pt 1 - YouTube
Speakers are these:
Avatar SST-2515D2/D4 - 15 inch Subwoofer
Cheap but good value and so far low distortion and values are as advertised.
What's the rationale behind the use of 2 tandem drivers operating in-phase? Nearly all the force generated by each motor is used to move the mass of its related cone (as opposed to the air load), so one driver would appear to be superfluous.
Thanks for that. I have to say, it looks mighty strange to me, but then again, I do remember the subwoofer which Celestion brought out in the 1980s, to pair with their upmarket SL600s - and of course, the reference mentions Celestion. (I wonder how many were sold - I've not seen any on the secondhand market.)
If SPLs do indeed sum, it's actually a rather neat way of arranging baffle-less woofers. (My main speakers are also baffle-less, though they use a more conventional arrangement for the two woofers.)
If SPLs do indeed sum, it's actually a rather neat way of arranging baffle-less woofers. (My main speakers are also baffle-less, though they use a more conventional arrangement for the two woofers.)
Here's a link to an article featuring the SL6000 system (SL600+sub):
Celestion System 6000 loudspeaker system | Stereophile.com
Celestion System 6000 loudspeaker system | Stereophile.com
Nice! Thank you for your kind words. I am glad that my 20-20k whitepaper was helpful and inspired you to try a nude OB system.
It looks like you are are doing all the right things vis a vis measuring, and have all the appropriate tools. You should be able to make the most out of this great setup. Also, you are correct that the mid and tweeter do not contribute to any vibration or movement, it's only the larger drivers that need to be decoupled.
