Hi all, I've been very intrigued with Zu Audio products and would like to make a sub like their Mini Method design. http://zuaudio.com/mini-method.asp
The other sub they have is called the Method and there is a good review of it here at 6moons http://6moons.com/audioreviews/zu3/method.html
If anyone has some suggestions on driver's, amp etc that would be great.
The criteria I'm looking for is;
#1 has to be a paper cone driver with high efficiency like the Zu
#2 has to be a sealed design like the Zu
It's not important for me to be able to break any spl records or crack the walls. I want to make a sub like the Zu that is the utmost in sound quality and natural to listen to.. Can it be done? Dave
The other sub they have is called the Method and there is a good review of it here at 6moons http://6moons.com/audioreviews/zu3/method.html
If anyone has some suggestions on driver's, amp etc that would be great.
The criteria I'm looking for is;
#1 has to be a paper cone driver with high efficiency like the Zu
#2 has to be a sealed design like the Zu
It's not important for me to be able to break any spl records or crack the walls. I want to make a sub like the Zu that is the utmost in sound quality and natural to listen to.. Can it be done? Dave
G'day Davecan
Good luck finding any driver that will perform as well as they claim.
Let's look at the numbers:
70L sealed
96dB efficiency @ 20Hz
Dual 15" drivers
Any driver you try in a sealed box of that size will have an efficiency of 74 or 75dB/W/M. That is a FAR CRY from the claimed 96dB figure. If they were right this would be the ONLY sub anyone would buy. It breaks Hoffman's Iron Law. It can even outgun the Danley DTS-20 Tapped horn, if you believe the marketing BS.
I smell fish.
Cheers
William Cowan
Good luck finding any driver that will perform as well as they claim.
Let's look at the numbers:
70L sealed
96dB efficiency @ 20Hz
Dual 15" drivers
Any driver you try in a sealed box of that size will have an efficiency of 74 or 75dB/W/M. That is a FAR CRY from the claimed 96dB figure. If they were right this would be the ONLY sub anyone would buy. It breaks Hoffman's Iron Law. It can even outgun the Danley DTS-20 Tapped horn, if you believe the marketing BS.
I smell fish.
Cheers
William Cowan
A couple of drivers like this 12" SC-1250 will bring you as close as you need to be
http://www.madisound.com/catalog/PDF/SC12NRT.pdf
A similar looking driver like the SBAcoustics 12" - but I dont think its available yet
http://www.madisound.com/catalog/PDF/SC12NRT.pdf
This AurumCantus could be an alternative, but I am unsure of the rated Xmax, whether its 8mm p/p, or 8mm+/- (16mm p/p)
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=296-434
There is a handy trick you could use if you only want one driver pr side or if you need even higher sensitivity - use a subamp with adjustable exstra 6db gain, you may have to build it yourself, either the amp or filter - Anthony Holton has something going on but also SKA can deliver a filter to do this, or use a simple gain module from ESP
The exstra 6db gain means that you may not be able to play insanely loud
http://www.madisound.com/catalog/PDF/SC12NRT.pdf
A similar looking driver like the SBAcoustics 12" - but I dont think its available yet
http://www.madisound.com/catalog/PDF/SC12NRT.pdf
This AurumCantus could be an alternative, but I am unsure of the rated Xmax, whether its 8mm p/p, or 8mm+/- (16mm p/p)
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=296-434
There is a handy trick you could use if you only want one driver pr side or if you need even higher sensitivity - use a subamp with adjustable exstra 6db gain, you may have to build it yourself, either the amp or filter - Anthony Holton has something going on but also SKA can deliver a filter to do this, or use a simple gain module from ESP
The exstra 6db gain means that you may not be able to play insanely loud
Thanks William and tinitus. Did you get to read the 6moons review William? I know Zu has been gaining a lot of respect so I'm not sure about the marketing hype but then again I'm not a speaker designer and have little experience..
The only sub box I ever made was way back in the early 90's for two 10'' MTX Blue Thunder subs in a sealed enclosure for a girlfriends car...
I'd love to hear the Zu Definitions but at $11,000 I'd need a big Lotto win to even think about getting those.. Just hoping that I can try to build a sub keeping close to the idea of the Zu mini Method. Looking for a reasonable sized sealed enclosure, paper cone driver(s) and the highest SQ that can be had for reasonable $, and of course the help of good people in the know like you guys!! Dave
The only sub box I ever made was way back in the early 90's for two 10'' MTX Blue Thunder subs in a sealed enclosure for a girlfriends car...
I'd love to hear the Zu Definitions but at $11,000 I'd need a big Lotto win to even think about getting those.. Just hoping that I can try to build a sub keeping close to the idea of the Zu mini Method. Looking for a reasonable sized sealed enclosure, paper cone driver(s) and the highest SQ that can be had for reasonable $, and of course the help of good people in the know like you guys!! Dave
tinitus said:
Just wanting to get close to the old school way where great sound came from natural paper cones, high efficiency etc ,and everything wasn't about massive x-max, big monster surrounds, giant magnets and mega watts, plus it goes against the norm which I like
If I had the room I'd do a horn (a big one) or do a IB set up but for now this is what I'm wanting to try.. It doesn't have to play that loud as I listen at low to medium volumes Dave
Could drivers like these be made to play lower than the fs? Eminence at Parts Express have many drivers but I just pulled this one as an example.. http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=290-593
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=294-480
Dave
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=294-480
Dave
G'day again DaveCan
>Did you get to read the 6moons review William?
Any reviewer that doesn't at least question such ridiculous claims is not worth reading, IMHO. Who can the general public turn to for a critique of the technology involved and the engineering applied to a product if they can't turn to the reviewer? The claims made by the manufacturer are outrageous yet the reviewer doesn't even question them. For me, audio is all about the proper application of sound engineering practice. This product is just smoke and mirrors. The product CANNOT work as advertised.
"with 120dB SPLs of non-distorted output claimed possible before THD bares its yellow fangs while your ears have long since fried and your beloved wall art crashed to the floor, its glass covers shattered to smithereens."
Stuff like this makes me laugh. Anyone who has tried knows that it is far harder achieving 120dB at the listening position at any bass frequency than what 6moons would lead you to believe. I have 8 very high quality 12" drivers (Peerless 830847) in my system in around 500 liters of sealed enclosures driven with multi kilowatt amps that can only just achieve this remarkable feat. I wish it were as easy as dropping two 15's into a 70L sealed box and powering them with a 200W amp!
This stuff is a joke in a DIY Subwoofer forum where many of the readers do know better.
To Zu's credit the sensitivity of the subwoofer is not included on their website, or on the PDF spec sheet: http://www.zucable.com/pdf/MethodSpecs.pdf
There is only one obvious lie in that document. It states: "120 dB without distortion" I'd put my money on it that the subwoofer won't achieve this specification across it's specified bandwidth of 20-200Hz.
I'll hop down from my soap box now.....
Cheers
William Cowan
>Did you get to read the 6moons review William?
Any reviewer that doesn't at least question such ridiculous claims is not worth reading, IMHO. Who can the general public turn to for a critique of the technology involved and the engineering applied to a product if they can't turn to the reviewer? The claims made by the manufacturer are outrageous yet the reviewer doesn't even question them. For me, audio is all about the proper application of sound engineering practice. This product is just smoke and mirrors. The product CANNOT work as advertised.
"with 120dB SPLs of non-distorted output claimed possible before THD bares its yellow fangs while your ears have long since fried and your beloved wall art crashed to the floor, its glass covers shattered to smithereens."
Stuff like this makes me laugh. Anyone who has tried knows that it is far harder achieving 120dB at the listening position at any bass frequency than what 6moons would lead you to believe. I have 8 very high quality 12" drivers (Peerless 830847) in my system in around 500 liters of sealed enclosures driven with multi kilowatt amps that can only just achieve this remarkable feat. I wish it were as easy as dropping two 15's into a 70L sealed box and powering them with a 200W amp!
This stuff is a joke in a DIY Subwoofer forum where many of the readers do know better.
To Zu's credit the sensitivity of the subwoofer is not included on their website, or on the PDF spec sheet: http://www.zucable.com/pdf/MethodSpecs.pdf
There is only one obvious lie in that document. It states: "120 dB without distortion" I'd put my money on it that the subwoofer won't achieve this specification across it's specified bandwidth of 20-200Hz.
I'll hop down from my soap box now.....
Cheers
William Cowan
Thanks William, I have no idea of what is and isn't correct( especially with complex math) as I said I'm not a speaker builder so your comments really help me..
I built myself a pair of BIB's a year or so ago for the Fostex fe108ez drivers and just love them. Been thinking on moving up to some BIB's for a 6'' driver as a compromise, but I'm afraid I may loose the beautiful mids of the 108's so hence the subwoofer idea... I'd love to do a BIB sub because the bass sounds so realistic and accurate through them but don't have the room etc.. Thanks for your time and help... Dave
I built myself a pair of BIB's a year or so ago for the Fostex fe108ez drivers and just love them. Been thinking on moving up to some BIB's for a 6'' driver as a compromise, but I'm afraid I may loose the beautiful mids of the 108's so hence the subwoofer idea... I'd love to do a BIB sub because the bass sounds so realistic and accurate through them but don't have the room etc.. Thanks for your time and help... Dave
Brett said:
Just so everyone is clear I only mentioned that because they gave a nice review of the Method sub.. I wasn't meaning that it was Gospel. I'm not a person that has lots of understanding with speaker building as far as all the specs go. I've only built 1 sub box before and it actually sounded fairly good, and I built with help in the Fullrange forum my pair of BIB's which I customized somewhat and they sound really good, but I do not understand the math etc
I sometime's check out 6moons to see the music section or to just look at all the different stuff I could never afford etc...In any event I have much respect for all you people on the forums here and elsewhere that take the time to share your knowledge with the not so educated like myself.. Dave
I'm glad you posted it, I needed a larf. WRT to LF, one thing you need to understand is the physics doesn't lie, and below 50Hz or so, it's basically all physics.
Hoffman's Iron Law is that you can have efficient, small and deep, but only two at a time. My LABs took 48 cu ft of room space. Each. But they were efficient and went deep-ish (and unbeleivably loud).
Hoffman's Iron Law is that you can have efficient, small and deep, but only two at a time. My LABs took 48 cu ft of room space. Each. But they were efficient and went deep-ish (and unbeleivably loud).
DaveCan, Not having a go at you.
It's a large part of High End HiFi industry that suffers from this disease. I'd guess the 6moons guys are paid to write crap like this, they wouldn't do it if it didn't put food on the table to feed the family, or perhaps provide new toys for the music room. Let's face it, a pair of Eminance 15" drivers in an MDF box does allow for some pretty good markups at a MSRP of US$2500. Zu Audio are doing something very poorly if they can't roll these things out the door for US$500ea.
I hope you won't be scared to ask questions in future It's the best way to learn.
Cheers
William Cowan
It's a large part of High End HiFi industry that suffers from this disease. I'd guess the 6moons guys are paid to write crap like this, they wouldn't do it if it didn't put food on the table to feed the family, or perhaps provide new toys for the music room. Let's face it, a pair of Eminance 15" drivers in an MDF box does allow for some pretty good markups at a MSRP of US$2500. Zu Audio are doing something very poorly if they can't roll these things out the door for US$500ea.
I hope you won't be scared to ask questions in future
It's the best way to learn.Cheers
William Cowan
The Zu sub is nothing more than an eq.ed sub.
If anything it is more prone to NON LINEAR distortion than other designs. Conversely linear distortion may well be quite a bit better than most designs. One of the on-line magazines did an article on subs "way down deep" I believe - anyway, one of the subs in that article was on the Bag End Elf sub - which is very similar in design.
It will however provide you with something that a great many subs won't - which is that "high eff." sound that is very dynamic/propulsive.
Additionally..
This is an excerpt of one of the offending "blurbs":
"The Method is good for 96dB efficiency at 20Hz and closer to 100dB at 40Hz, with 120dB SPLs of non-distorted output claimed possible before THD bares its yellow fangs while your ears have long since fried and your beloved wall art crashed to the floor, its glass covers shattered to smithereens."
Note that the WRITER/6moons is NOT making the claims - Zu is.
2nd, the DRIVERS together might well be that in an Infinite baffle.
3rd, they never mention what the level of THD is that they deem is "non-distorted", nor where that 120 db measurement was taken (i.e. what freq.).
That my friends is superb marketing.
(..not just putting it out there, but getting a reviewer to parrot it. )
If anything it is more prone to NON LINEAR distortion than other designs. Conversely linear distortion may well be quite a bit better than most designs. One of the on-line magazines did an article on subs "way down deep" I believe - anyway, one of the subs in that article was on the Bag End Elf sub - which is very similar in design.
It will however provide you with something that a great many subs won't - which is that "high eff." sound that is very dynamic/propulsive.
Additionally..
This is an excerpt of one of the offending "blurbs":
"The Method is good for 96dB efficiency at 20Hz and closer to 100dB at 40Hz, with 120dB SPLs of non-distorted output claimed possible before THD bares its yellow fangs while your ears have long since fried and your beloved wall art crashed to the floor, its glass covers shattered to smithereens."
Note that the WRITER/6moons is NOT making the claims - Zu is.
2nd, the DRIVERS together might well be that in an Infinite baffle.
3rd, they never mention what the level of THD is that they deem is "non-distorted", nor where that 120 db measurement was taken (i.e. what freq.).
That my friends is superb marketing.
(..not just putting it out there, but getting a reviewer to parrot it.
)
Well looking beyond the 6moons and Zu marketing thing ,can anyone suggest or sim some high eff paper cone drivers in a sealed enclosure that would make one's jaw drop for SQ and not just because it rattles everything... It could be 2 10'' drivers like the Mini or just one good driver. My system is a Decware Taboo Single Ended Pentode amp 6wx2 rms and a pair of Fostex fe108ez drivers in BIB horns.
I may not bother with the sub just feeling it out as of yet. I sent an e-mail to Zu to let them know about the thread , so if they'd like to respond ,and got a nice quick reply back which I thought was very nice ( that was my first ever e-mail to them)... Anyhow I like the idea of a pair of 10'''s working together like in the Mini, but if there isn't any drivers out there that would work that are 95+ db then maybe I'll just keep being happy with what I have...
Maybe this could end up being a good project and somewhat of a challenge, not to re-create the claimed specs of the Zu stuff, but just a great SQ design first and formost that is different from the norm etc.
Dave
I may not bother with the sub just feeling it out as of yet. I sent an e-mail to Zu to let them know about the thread , so if they'd like to respond ,and got a nice quick reply back which I thought was very nice ( that was my first ever e-mail to them)... Anyhow I like the idea of a pair of 10'''s working together like in the Mini, but if there isn't any drivers out there that would work that are 95+ db then maybe I'll just keep being happy with what I have...
Maybe this could end up being a good project and somewhat of a challenge, not to re-create the claimed specs of the Zu stuff, but just a great SQ design first and formost that is different from the norm etc.
Dave
Large HE drivers are the province of Pro audio applications like PA. They don't need extreme LF, so most have an Fs in the 40Hz region and in a sealed box, that'll increase, or the box'll be huge. Remember, small, deep and efficient, pick 2.DaveCan said:
A JBL 2245 in a sealed box with a Linkwitz Transform could do it, but it'll still be a couple of hundred litres for an eventual F3 of 20Hz and Q=0.5.
If you own your own home and have a loft or basement space that's suitable, an Infinite Baffle sub might be easiest. Use a quad of the Dayton 15 IB drivers/channel from Parts Express.
http://home.comcast.net/~infinitelybaffled/
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=295-455
Otherwise visit the Collaborative Tapped Horn thread here in subwoofer section and build the final design he suggested. I think the info is also on his webpage which you can link from an earlier post. Big though.
Hi Brett, Can't do the IB or I would give that a go, also ditto with a big horn. I saw the horns at CowanAudio, now thats what I call ''man sized'' and I would love to give that a try, reminds me sort of a BIB cab in a way and I bet they perform awesome and more importantly sound very good.. This may be of some interest, how could this work if it was tweaked in someway? http://www.madisound.com/catalog/pr...=1768&osCsid=a95f62a5707d0fbbe88cbae35cef4e4b
Can't get the link to work.. Oh well it was a 15'' Eminence driver at Madisound that was specially made for sub duty for the high eff single driver crowd etc..
Can't get the link to work.. Oh well it was a 15'' Eminence driver at Madisound that was specially made for sub duty for the high eff single driver crowd etc..
http://www.madisound.com/catalog/product_info.php?manufacturers_id=127&products_id=1768&osCsid=c59827eeef298aa2012614ec83896047
Q is too low for a sealed box. Modelling it sealed I get an F3 at 88Hz for a Q=0.707 in 34L. Best suited for ported boxes.
Q is too low for a sealed box. Modelling it sealed I get an F3 at 88Hz for a Q=0.707 in 34L. Best suited for ported boxes.
There is a modest solution.
1st of all:
you get +3db for each near boundary - that means putting a sub in a room corner nets you +9db. Note however that you should have the sub fairly well highpassed near 40 Hz (..i.e. at least 12db an octave, and preferably 24db an octave).
2nd,
Most rooms experience an additional room gain of about +5 to 6 db at 20 Hz.
3rd,
Reduce the vas by just about half by doubling up on the drivers in a push-push isobaric configuration. (i.e. one driver right behind the other both in-phase.) Wire in parallel.
Finally,
For an additional +3 to 6 db of gain and a minor lessening in deviations due to room modes:
Make *2* subs place each in opposite corners and again make sure that each is highpassed near 40 Hz. *IF* you have an amplifier rated for a 2 ohm load then you can parallel the 2nd sub with the first, if not then you will need two sub amps.
This driver:
http://www.madisound.com/catalog/product_info.php?cPath=45_228_260&products_id=1768
Should do the trick in an isobaric config. with about 5 cubic feet of sealed enclosure volume. (note that Qtc is low at this volume - which should give a very tight dynamic sound.) As I suggested in an earlier thread, it could look a lot like an art pedestal.. like a 18-19 inch square top/bottom version of this (with the driver facing the floor but with about 2 inches of clearance):
http://www.hammacher.com/publish/72000.asp?promo=xsells
1st of all:
you get +3db for each near boundary - that means putting a sub in a room corner nets you +9db. Note however that you should have the sub fairly well highpassed near 40 Hz (..i.e. at least 12db an octave, and preferably 24db an octave).
2nd,
Most rooms experience an additional room gain of about +5 to 6 db at 20 Hz.
3rd,
Reduce the vas by just about half by doubling up on the drivers in a push-push isobaric configuration. (i.e. one driver right behind the other both in-phase.) Wire in parallel.
Finally,
For an additional +3 to 6 db of gain and a minor lessening in deviations due to room modes:
Make *2* subs place each in opposite corners and again make sure that each is highpassed near 40 Hz. *IF* you have an amplifier rated for a 2 ohm load then you can parallel the 2nd sub with the first, if not then you will need two sub amps.
This driver:
http://www.madisound.com/catalog/product_info.php?cPath=45_228_260&products_id=1768
Should do the trick in an isobaric config. with about 5 cubic feet of sealed enclosure volume. (note that Qtc is low at this volume - which should give a very tight dynamic sound.) As I suggested in an earlier thread, it could look a lot like an art pedestal.. like a 18-19 inch square top/bottom version of this (with the driver facing the floor but with about 2 inches of clearance):
http://www.hammacher.com/publish/72000.asp?promo=xsells
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.