LOL, I like how you used the sub amp from an existing powered sub in the video after the first video! I've been thinking about doing the same type of thing with the powered 6.5 sub in our bedroom.
hi BesPav - I like the looks of your cabinet - that driver sure has "high Q". I had a pair of vintage EV!P15B in Karlson cabinets - drums were pounding on Nick Cave's "Murder Ballads" 
SPL [dB] 98 dB
Fs [Hz] 48 Hz
Qts 1,24
Vas [L] 68 l
Re [Ohm] 7 ohm
Le (1kHz) [mH] 1,08 mH
BL 7,6 N/A
Sd 517 cm2
Qms 5,56
Qes 1,59
Mms [g] 43,3 g
Cms [mm/N] 0,25 mm/N
that cheap fullrange runs out of its 2mm xmax pretty fast - what other drivers might work?
SPL [dB] 98 dB
Fs [Hz] 48 Hz
Qts 1,24
Vas [L] 68 l
Re [Ohm] 7 ohm
Le (1kHz) [mH] 1,08 mH
BL 7,6 N/A
Sd 517 cm2
Qms 5,56
Qes 1,59
Mms [g] 43,3 g
Cms [mm/N] 0,25 mm/N
that cheap fullrange runs out of its 2mm xmax pretty fast - what other drivers might work?
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It is a nice ending to the video. 10 watts is plenty when the efficiency is at 108 dB/w/m.
Every time he fires up his Logitec/ROAR212 we get mad at him. Everything rattles in our house.
It is a fun and capable basshorn. It is overkill to use a ROAR12 in a normal residential living room, but its plenty of fun.
Regards,
Johannes
[OFF]HI, Freddi!
Yes, but it have Xmech at about 4 mm and due to front horn speaker have good directivity even at the low-mids.
It couldn't reach 120 dB, it couldn't resist of 400 Wt and it couldn't be the main speaker in PA-systems.
But it sounds pretty cool to be build and then it will be the standalone speaker at any small party with tight budget. It doesn't need much power, just believe, your legs starts to dancing around and you couldn't still hold the volume knob.
Since this is offtopic here a PM was sent.
[/OFF]
For those who worry over the jagged response curve of the ROAR series should have a look at Tom Danleys BC415 published response curve.
http://www.danleysoundlabs.com/danley/wp-content/uploads/2013/06/BC-415-spec-sheet2.pdf
The BC415 has gotten really good reviews - despite the "horrendous" 12 dB dip just above the passband. It also has a large midbass peak of about 6 - 8 dB centered at 93 Hz. If Tom Danley designs and produces stuff with this kind of behavior, then our ROAR series can't be all that bad.
It seems that a ruler-flat response curve in Hornresp does not always lead to a perfect bass horn in real life.
Cheers,
Johannes
http://www.danleysoundlabs.com/danley/wp-content/uploads/2013/06/BC-415-spec-sheet2.pdf
The BC415 has gotten really good reviews - despite the "horrendous" 12 dB dip just above the passband. It also has a large midbass peak of about 6 - 8 dB centered at 93 Hz. If Tom Danley designs and produces stuff with this kind of behavior, then our ROAR series can't be all that bad.
It seems that a ruler-flat response curve in Hornresp does not always lead to a perfect bass horn in real life.
Cheers,
Johannes
That's a really strange interpretation of the linked frequency response graph. If you eq down the broad peak centered at ~90 hz then there's no dip left. You just have flat response.
In the case of your ROAR series the dip is over 1/2 octave wide, 22 db deep, and there's no way to fix it with dsp or any other method.
Danley's frequency response also seems to be a bit underdamped as per usual, so the frequency response will actually likely get flatter as it enters power compression territory. On the other hand your ROAR is already overdamped and the frequency response will get worse as it encounters power compression.
I'm not sure what the issue is here - if it's that you can't understand the issue with a greater than 1/2 octave wide 22 db deep notch in response, or if you just don't care, or if you are just trying to save face at this point.
Regardless, it's easy enough to sim the situation to find out how bad the issue is. Using Bagby's PCD or other similar software that will allow you to sim an active crossover, try inputting the .frd files for this ROAR sub and any mains tops you like and see if you can get a smooth transition through the crossover region.
PLEASE start a new thread. Interesting design!
I am not deterred at all with the curve. That said, until some measurements are posted, this is all elementary.
a thread on BesPav's BP-horn approach would be interesting - here;s a Fane 250tC 1pi at rated xmax (~125 watts) http://i.imgur.com/1MUH2zc.jpg
My terribly delayed response + some data to contribute to the ROAR effort
Thank you Johannes!
The "New Sub Design" discussion has been a great learning experience for me over the last few years and a few useful things have come out of it but most of which had a focus on being compact which of course sacrifices efficiency if we want low tunings.... Hoffman's Iron Law can be such a bastard ..
On the other hand larger cabinets with higher levels of efficiency are something that i also find very interesting, and the ROAR series is just that sort of animal
......
It is good to see that builders are reporting success despite the controversial midbass response hole and potential (or theoretical?) integration difficulties that so far have not been reported by any real-wold users (not that i have seen anyhow) ....
I hope to see many more reports, feedback and more measured response charts posted so that we can increase our understanding of the way this design behaves in reality
..... Of course we would all like to see the data come in at a faster pace but we just have to be patient .... These things can take time
, i get it .....
So, ok , i have something that i would like to share.
The other day i simulated three different 250 liter cabinets tuned to 40hz and loaded with the 15LB100 from Thomann (much thanks to Sebastian Schlager for providing the measured T/S parameters) .....................The first cabinet was a a ROAR15 with custom CSAs optimized for the 15LB100 , the second was a Super Planar sub (compound loaded quarterwave, parallel tuned 6th order sort of thing) , and the third cabinet was just a generic 40hz Tapped Horn with constant expansion rate ....... They all looked pretty good to be honest .... The custom ROAR15 pulled ahead of the Tapped Horn in terms of efficiency but didn't have as much bandwidth ... The highly optimized Super Planar was only the smallest hair away from keeping up with the ROAR's efficiency but had a bit more bandwidth carrying out to almost 200hz .................... Surely the Tapped Horn could have been made to perform a little better with more than one expansion rate but i was keeping it simple ....
NOTE: To be fair the 15LB100 actually simulates just fine in a 160 liter 40hz Tapped Horn, so 250L could be considered an unnecessarily large internal volume for that alignment (with such a driver and tuning) .......
Below are the inputs that i used for the customized ROAR , followed by the simulated response and group delay ......
Respectable output for some budget drivers i think
and the group delay is reasonably low
Here are the details for the 15LB100-8W from Thomann ..... Seems to have very suitable parameters for the ROAR .... Strong motor... The Fs and Qts are in appropriate ranges... ... Nice low Le figure as well which is a bonus!
Sebastian has both the 15LB100 and it's bigger brother the 18-500 and he says they seem to be shipping these two driver models with the same motor now (at least as far as he can tell from the ones that he received) , and the measured T/S parameters do reflect what he is saying ....
I hope that someone finds the above somehow interesting or helpful in some way .......
Since the ease of integration (with tops) has been called into question here i would like to throw an idea out there at the risk of being accused of shamelessly promoting one of my more current project concepts Hehehe
There have been a few sets of Super Planar tops built along with two subs (by a friend back east, Mr Vansickle in NC) ... Another friend whom we know as GKH in Austria may be building the next set soon which will provide more data for us to work with .... They are 6th order and produce midbass with authority, and can be tuned high... ....... (link below)
SUPER PLANAR LINK click here to see what i am rattling on about
The Super Planar idea is still in a somewhat experimental development stage at this point even though there has been some builds with great results, much like the ROAR series in that regard, but for someone who wants to try something new and unusual this sort of thing can be a fun project!
......
Thank you Johannes!
The "New Sub Design" discussion has been a great learning experience for me over the last few years and a few useful things have come out of it
but most of which had a focus on being compact which of course sacrifices efficiency if we want low tunings.... Hoffman's Iron Law can be such a bastard ..On the other hand larger cabinets with higher levels of efficiency are something that i also find very interesting, and the ROAR series is just that sort of animal
...... It is good to see that builders are reporting success despite the controversial midbass response hole and potential (or theoretical?) integration difficulties that so far have not been reported by any real-wold users (not that i have seen anyhow) ....
I hope to see many more reports, feedback and more measured response charts posted so that we can increase our understanding of the way this design behaves in reality
..... Of course we would all like to see the data come in at a faster pace but we just have to be patient .... These things can take time, i get it ..... So, ok , i have something that i would like to share.
The other day i simulated three different 250 liter cabinets tuned to 40hz and loaded with the 15LB100 from Thomann (much thanks to Sebastian Schlager for providing the measured T/S parameters) .....................The first cabinet was a a ROAR15 with custom CSAs optimized for the 15LB100 , the second was a Super Planar sub (compound loaded quarterwave, parallel tuned 6th order sort of thing) , and the third cabinet was just a generic 40hz Tapped Horn with constant expansion rate ....... They all looked pretty good to be honest
.... The custom ROAR15 pulled ahead of the Tapped Horn in terms of efficiency but didn't have as much bandwidth ... The highly optimized Super Planar was only the smallest hair away from keeping up with the ROAR's efficiency but had a bit more bandwidth carrying out to almost 200hz .................... Surely the Tapped Horn could have been made to perform a little better with more than one expansion rate but i was keeping it simple .... NOTE: To be fair the 15LB100 actually simulates just fine in a 160 liter 40hz Tapped Horn, so 250L could be considered an unnecessarily large internal volume for that alignment (with such a driver and tuning) .......
Below are the inputs that i used for the customized ROAR , followed by the simulated response and group delay ......
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Respectable output for some budget drivers i think
An externally hosted image should be here but it was not working when we last tested it.
and the group delay is reasonably low
An externally hosted image should be here but it was not working when we last tested it.
Here are the details for the 15LB100-8W from Thomann ..... Seems to have very suitable parameters for the ROAR .... Strong motor... The Fs and Qts are in appropriate ranges... ... Nice low Le figure as well which is a bonus!
Sebastian has both the 15LB100 and it's bigger brother the 18-500 and he says they seem to be shipping these two driver models with the same motor now (at least as far as he can tell from the ones that he received) , and the measured T/S parameters do reflect what he is saying ....
An externally hosted image should be here but it was not working when we last tested it.
I hope that someone finds the above somehow interesting or helpful in some way .......
Since the ease of integration (with tops) has been called into question here i would like to throw an idea out there at the risk of being accused of shamelessly promoting one of my more current project concepts
HeheheThere have been a few sets of Super Planar tops built along with two subs (by a friend back east, Mr Vansickle in NC) ... Another friend whom we know as GKH in Austria may be building the next set soon which will provide more data for us to work with .... They are 6th order and produce midbass with authority, and can be tuned high... ....... (link below)
SUPER PLANAR LINK click here to see what i am rattling on about
The Super Planar idea is still in a somewhat experimental development stage at this point even though there has been some builds with great results, much like the ROAR series in that regard, but for someone who wants to try something new and unusual this sort of thing can be a fun project!
......
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ZeroD and BP1Fanatic Thanks guys!
Hello BP1Fan!
Yeah? Cool It is a big box but maybe would go well in a SUV?
Ohh damn, yes, you are right ....
Thank you ZeroD Sir, I appreciate that!
Hello BP1Fan!
Yeah? Cool
It is a big box but maybe would go well in a SUV?Ohh damn, yes, you are right ....
Always good to see your postings etc
Thank you ZeroD Sir, I appreciate that!
Hello BP1Fan!
Yeah? Cool
Or, an extended cab pickup!
Meanwhile somewhere in Sweden...
Not really the intended user case, just moved in to this place and I'm sure I'm not making any friends... even at very low levels it saturates the room with energy, walls vibrate and you feel it everywhere.
It does sounds good though, can't really say how much the room plays a part in that result but still, I have only heard it outside before and there are similarities to the sound and character.
Not really the intended user case, just moved in to this place and I'm sure I'm not making any friends... even at very low levels it saturates the room with energy, walls vibrate and you feel it everywhere.
It does sounds good though, can't really say how much the room plays a part in that result but still, I have only heard it outside before and there are similarities to the sound and character.
He-he. Let's go further.
This driver needs a lower rear chamber volume for good damping and rising of Q.
My suggestion is 15 liters.
Having 5,25 mm of Xmax it's probably have ~8 mm of Xmech.
There are no reasons not to use it fully.
So, 15 liter RC + Butterworth 2-order HP at 70 Hz + 600 Wt could provide enough kick to any possible butt:
Keep in mind, it's loaded with front horn.
In the 1-5 kHz we will have good sensitivity rise due to front horn, higher driver itself have a hair lower 110 dB.
Just add capable sub and you're in.