Very nice shape, design etc...Steve, Dave, Scott...
I like the results for 168 and hemp, and you realize folks that now there is a room friendly load for the Hemp cone that performs well, and looks cool. Low port velocity, all the good, none of the bad.
I think these are perfect for the hemp cones, V2 coming soon.
I like the results for 168 and hemp, and you realize folks that now there is a room friendly load for the Hemp cone that performs well, and looks cool. Low port velocity, all the good, none of the bad.
I think these are perfect for the hemp cones, V2 coming soon.
dmason said:
I look forward to hearing about the 'Hemptronomes'!
Off the topic, but here's one channel of my 'V1' Hempsters, glue barely dry, edges not trimmed, but set up and playing. Roughly 3 ft^3, 4"dia x 4" long port on the right side. Assymetrical driver placement determined by the smoothest curve I could get in "The Edge". May need some baffle step correction, we'll see after some break in time. The Metronome cab might be a nice upgrade. Although the Bruce BVR might look kind of cool, too...
Attachments
Not sure what we are looking at, but looks like a BIB next to the blacked out cabs in topic. The V1 FR8 should be okay without BSC in that size cab.
I am really interested in trying the V2 in this design. We could call it ....The Hempodrome... as a subtle tip o the hat to our British colleagues.
I am really interested in trying the V2 in this design. We could call it ....The Hempodrome... as a subtle tip o the hat to our British colleagues.
A fine moose, Dave. 
As Dave notes, low DF amps like Steve & Steve's should be fine without correction as we've deliberately set these things up as ~max flat in 1/2 space. Without BSC, but with some room-gain and with a suitable amplifier they should be quite nicely balanced. Of course, the beauty of the ML designs is that they're usually very easy to tune by adjusting the port length, rather than needing massive cabinet changes. Could be a good option for the hemp drivers.
Now, why is it that I didn't think to try modelling the hempster in the Bruce V1.1 double BVR horn? Sorry, off topic. But it shall be done. I'll look at those Supravoxes in Metronomes first though. Back later.
BTW -love the 125 BIBs.
As Dave notes, low DF amps like Steve & Steve's should be fine without correction as we've deliberately set these things up as ~max flat in 1/2 space. Without BSC, but with some room-gain and with a suitable amplifier they should be quite nicely balanced. Of course, the beauty of the ML designs is that they're usually very easy to tune by adjusting the port length, rather than needing massive cabinet changes. Could be a good option for the hemp drivers.
Now, why is it that I didn't think to try modelling the hempster in the Bruce V1.1 double BVR horn? Sorry, off topic. But it shall be done. I'll look at those Supravoxes in Metronomes first though. Back later.
BTW -love the 125 BIBs.
Can one of the Metronome fans please explain why this cabinet is not just a simple Bass Reflex?
Sure looks like one to me, (single chamber box, tuned port) but I must be missing something in the tuning. Does it have to do with length of the cabinet, driver placement, stuffing, something else?
Thanks.
Sure looks like one to me, (single chamber box, tuned port) but I must be missing something in the tuning. Does it have to do with length of the cabinet, driver placement, stuffing, something else?
Thanks.
panomaniac said:
That question has been asked so many times, there is a web page.
http://geocities.com/rbrines1/Pages/QWR_not_BR.html
dave
Illustration based on ANSYS simulations by Martin King for the article cited below..
For the whole story:
Design and Construction of a Mass Loaded Tapered Quarter Wavelength Tube (ML TQWT) Using the Fostex FE-164 Full Range Driver. By Martin J. King, 4/21/01
here http://www.quarter-wave.com/Project02/Project02.html
They show a BR box and an ML-TQWT resonance behavior. These pretty clearly illustrate the different behavior of the 2 boxes.
dave
For the whole story:
Design and Construction of a Mass Loaded Tapered Quarter Wavelength Tube (ML TQWT) Using the Fostex FE-164 Full Range Driver. By Martin J. King, 4/21/01
here http://www.quarter-wave.com/Project02/Project02.html
They show a BR box and an ML-TQWT resonance behavior. These pretty clearly illustrate the different behavior of the 2 boxes.
dave
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Just to extend that a bit; here's the short version.
The Metronome is (now!) a Mass Loaded Quarter Wave Resonator. All pipes that are open at one end and sealed at the other resonate at 1/4 wavelength of a particular frequency. The frequecy at which they resonate is determined by both line length and the taper ratio. The traditional 'take a frequency and /4 to get the length of a QWR' only works for straight, untapered lines. A positive tapered pipe (i.e an expanding line, which really is a variation on the horn theme, when all is said and done) needs to be considerably longer than a straight pipe for the same tuning frequnecy, while a negative taper pipe (i.e one which starts wide and gets progressively narrower) can be considerably shorter. See Martin King's Classic TL alignment tables for more detail.
When you mass load a design; you restrict the area of the terminus; usually with a slot port, or a circular port of the type used in reflex cabinets. The air-mass in the choked off terminus places an additional load upon the quarter-wave resonance generated by the enclosure. This in turn lowers the frequency of the fundamental resonance, and also, usefully, dramatically damps down harmonic resonances. You can tune the response to an extent by adjusting the size of this choked terminus -longer ports provide more damping, shorter ports less. Ditto for diameter: the narrower, the higher the damping applied.
On a graph, the response of a well designed MLTL (I actually prefer the moniker ML QWR, but most people are more familiar with the TL, even if it's not a particularly accurate description of this sort of cabinet) can look fairly similar to a well designed reflex cabinet. However, the fundamental approach to creating the response is very different; in addition, they rarely sound the same; the MLTL having a cleaner presentation in the bass and midrange; helped by the stuffing, and the careful tailoring of cabinet resonances.
Hope this helps
Scott
The Metronome is (now!) a Mass Loaded Quarter Wave Resonator. All pipes that are open at one end and sealed at the other resonate at 1/4 wavelength of a particular frequency. The frequecy at which they resonate is determined by both line length and the taper ratio. The traditional 'take a frequency and /4 to get the length of a QWR' only works for straight, untapered lines. A positive tapered pipe (i.e an expanding line, which really is a variation on the horn theme, when all is said and done) needs to be considerably longer than a straight pipe for the same tuning frequnecy, while a negative taper pipe (i.e one which starts wide and gets progressively narrower) can be considerably shorter. See Martin King's Classic TL alignment tables for more detail.
When you mass load a design; you restrict the area of the terminus; usually with a slot port, or a circular port of the type used in reflex cabinets. The air-mass in the choked off terminus places an additional load upon the quarter-wave resonance
On a graph, the response of a well designed MLTL (I actually prefer the moniker ML QWR, but most people are more familiar with the TL, even if it's not a particularly accurate description of this sort of cabinet) can look fairly similar to a well designed reflex cabinet. However, the fundamental approach to creating the response is very different; in addition, they rarely sound the same; the MLTL having a cleaner presentation in the bass and midrange; helped by the stuffing, and the careful tailoring of cabinet resonances.
Hope this helps
Scott
Hi Guys
Reading the posts concerning Ed Swift's (Vitalstates) big Fostex TQWTs I thought I'd bring this topic to the top again.
Below you can see a picture of Ed's speakers at EggFest, along with my Metronomes, being driven by my PT15 SE amp setup.
Playing Robin "Trower's Bridge of Sighs" on vinyl they kicked butt like few other speakers I have heard.
Just a note on the Metronomes.
Dave's phase plug mods have worked superbly on the drivers giving a lovely sweet, open sound.
I'm also currently in correspondence with a guy in London who is building a pair from English oak with the phase plug mod.
That's nice because soon there will be two Metronomes on the planet instead of the current one.
Along with Ed's TQWTs things are moving in Blighty!
If you guys would like to see a full lowdown on the characters and equipment that made up the EggFest you can go here to find out
http://web.mac.com/scress1958/iWeb/Steves_Tube_Trials/EggFest_4.html
Steve
Reading the posts concerning Ed Swift's (Vitalstates) big Fostex TQWTs I thought I'd bring this topic to the top again.
Below you can see a picture of Ed's speakers at EggFest, along with my Metronomes, being driven by my PT15 SE amp setup.
Playing Robin "Trower's Bridge of Sighs" on vinyl they kicked butt like few other speakers I have heard.
Just a note on the Metronomes.
Dave's phase plug mods have worked superbly on the drivers giving a lovely sweet, open sound.
I'm also currently in correspondence with a guy in London who is building a pair from English oak with the phase plug mod.
That's nice because soon there will be two Metronomes on the planet instead of the current one.
Along with Ed's TQWTs things are moving in Blighty!
If you guys would like to see a full lowdown on the characters and equipment that made up the EggFest you can go here to find out
http://web.mac.com/scress1958/iWeb/Steves_Tube_Trials/EggFest_4.html
Steve
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If you read through the page you'll see several links, as well as different designs for larger versions etc. Here's Steve's own page: http://web.mac.com/scress1958/iWeb/Steves_Tube_Trials/Home.html
And the work in progress Planet10 page: http://www.planet10-hifi.com/metronome.html
Nice. Oak with 108s and phase plugs... I'd love to hear those. The Metronomes remain probably the best small speaker I know of, particularly when coupled with a decent small sub.
I think the design idea is actually becoming quite popular Steve -lots of people like the concept, and I think there's about a dozen now in-line waiting for the building season to begin. Hope so as IMO the idea is well worth pursuing, especially for those who require very high WAF! I've yet to come across a design short of Terry Cain's stunning examples of the cabinet-maker's art which fulfils this role so well. If Terry was well enough, I bet he'd be one of the first to fire up the table-saw and start experiementing.
Quarter wave loading is one of the forgotten speaker forms, particularly in the UK. It's only recently, thanks initially to the Single Driver Site, the old, now defunct full-range forum, and a few pundits like GM who never forgot in the first place, that a large[ish] number of people have rediscovered what it can offer. While IMO it will always be a specialised load unlikely to make inroads into the mainstream, it's now back with a vengence with some really good new ideas, and superb implementations of old ones emerging. Plus, we have software available which can assist in the design process if required. Great stuff.
And the work in progress Planet10 page: http://www.planet10-hifi.com/metronome.html
Nice. Oak with 108s and phase plugs... I'd love to hear those. The Metronomes remain probably the best small speaker I know of, particularly when coupled with a decent small sub.
I think the design idea is actually becoming quite popular Steve -lots of people like the concept, and I think there's about a dozen now in-line waiting for the building season to begin. Hope so as IMO the idea is well worth pursuing, especially for those who require very high WAF! I've yet to come across a design short of Terry Cain's stunning examples of the cabinet-maker's art which fulfils this role so well. If Terry was well enough, I bet he'd be one of the first to fire up the table-saw and start experiementing.
Quarter wave loading is one of the forgotten speaker forms, particularly in the UK. It's only recently, thanks initially to the Single Driver Site, the old, now defunct full-range forum, and a few pundits like GM who never forgot in the first place, that a large[ish] number of people have rediscovered what it can offer. While IMO it will always be a specialised load unlikely to make inroads into the mainstream, it's now back with a vengence with some really good new ideas, and superb implementations of old ones emerging. Plus, we have software available which can assist in the design process if required. Great stuff.
Hi Gychang
Thre are two places where you can get information on the Metronome.
Dave (Planet10) has a web page that is currently not live where he and Scott have worked out some designs for bigger enclosures plus my original is there. A post from Scott arrived as I was doing this reply so I won't repeat the links on here.
Visit the Metronome 1 link on my website and the plans for my speaker drawn up by Dave can be downloaded from there.
Regarding the sub issue. These speakers integrate so well with a good active sub that when they were being demoed at EggFest not one person detected the prescence of the subwoofer.
A couple of people could not understand how such a small speaker was putting out such low frequencies until I pointed out the sub in the corner.
The only time it was detected was when I was doing my sound check at the beginning with a bit of Joss Stone and it was quite obvious that the sub was far too loud. Once it had been adjusted for the room it disappeared.
Steve
Thre are two places where you can get information on the Metronome.
Dave (Planet10) has a web page that is currently not live where he and Scott have worked out some designs for bigger enclosures plus my original is there. A post from Scott arrived as I was doing this reply so I won't repeat the links on here.
Visit the Metronome 1 link on my website and the plans for my speaker drawn up by Dave can be downloaded from there.
Regarding the sub issue. These speakers integrate so well with a good active sub that when they were being demoed at EggFest not one person detected the prescence of the subwoofer.
A couple of people could not understand how such a small speaker was putting out such low frequencies until I pointed out the sub in the corner.
The only time it was detected was when I was doing my sound check at the beginning with a bit of Joss Stone and it was quite obvious that the sub was far too loud. Once it had been adjusted for the room it disappeared.
Steve
possible with RS 40-1354 or TangBand 3"?
I have these speakers waiting for the cabinets...
RadioShack: 40-1354 and TangBand W3-871S 3" DRIVER (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=264-813)
Love the styling, I realize I will need a subwoofer.
Any of the smart folks here offer some advise?
1. Does the software say it is reasonable given the speaker parameters?
2. What dimensions or modification may be needed?
thanks,
gychang
I have these speakers waiting for the cabinets...
RadioShack: 40-1354 and TangBand W3-871S 3" DRIVER (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=264-813)
Love the styling, I realize I will need a subwoofer.
Any of the smart folks here offer some advise?
1. Does the software say it is reasonable given the speaker parameters?
2. What dimensions or modification may be needed?
thanks,
gychang