I am familiar with that design by Mr. Dlugos.
It's a folded MLTL, not same as Metronome (MLQQWT).
What I was talking about is a different form of Semi-Omni Metronome, what I have in mind results in a rectilinear form factor on the outside, while still having the metronome taper folded in half inside. I'm thinking inside the box here....
I tried to do a Sketchup model a couple nights ago, didn't get far, too tired from a long day. I plan to try again when I have the energy.
Just kicking back to some Miles Davis tracks from his first great quintet and sextet period. "Kind of Blue" has just struck up and we're in the studio with the band. I need to turn things down
It's taken about eight days for the bass/mid drivers to loosen up and let the bass out fully, but now they are probably about there.
The against the wall bass alignment has worked out well. The down-firing mass loading port output, coupled to the floor and the up-firing bass/mid, is giving the speaker the best chance of working with the room acoustic, to produce an even output, that tracks bass lines up and down the scale, without emphasising any particular frequency over another unless you actually hear a string being plucked harder for effect.
The room is not being excited, so the room is not interfering with bass instruments. This is allowing individual instrument characteristics to be reproduced clearly. For example, little string bends, buzzes, hesitations and subtle beat dragging or subtle pushes to the rhythm, all come over cleanly and clearly, and make musical sense in the context of each recording. Texture, timbre and tone is spot on.
Another little touch these speakers have is the chameleon-like ability to allow the room to "become" the venue in which the performance is happening. On the right recording, they are capable of transporting you right into the action. You get to hear studio walls, slap echoes off back walls, voices are given acoustic environments.
For example, on Dusty Springfield "The Look of Love" from the original Colgems, stereo vinyl of the soundtrack to the sixties David Niven Bond spoof "Casino Royale" the vocal booth can be heard. Dusty seems to be singing from a pan-pot positioned dry space, dead centre of the more wet Abbey Road acoustic of the orchestra and the Herb Alpert brass. All the time the subtle rhythmic device of a scraper purrs along hard left. Niiice
These speakers may not be everyone's cup of tea. Heavy rock afficionados may find the slightly distant perspective, these speakers produce, not quite in 'yer face enough. They will play rock with great dynamics and big tone, but that nth degree of oomph may be lacking for some listeners. I like tone and harmonics over ultimate welly, but others will differ in their preferences, which is fine. We don't all like the same thing, and speakers are highly subjective at the best of times.
Big classical works come over very well, as does choral, opera, chamber music, early music, jazz, blues, soul, fifties rock n roll, sixties pop, singer/songwriter country, bluegrass, big band swing, Latin, and electronic of both the Klaus Schulze/TD and Orbital persuasions.
The OmniMets have taken up permanent residence in the system now.
It's taken about eight days for the bass/mid drivers to loosen up and let the bass out fully, but now they are probably about there.
The against the wall bass alignment has worked out well. The down-firing mass loading port output, coupled to the floor and the up-firing bass/mid, is giving the speaker the best chance of working with the room acoustic, to produce an even output, that tracks bass lines up and down the scale, without emphasising any particular frequency over another unless you actually hear a string being plucked harder for effect.
The room is not being excited, so the room is not interfering with bass instruments. This is allowing individual instrument characteristics to be reproduced clearly. For example, little string bends, buzzes, hesitations and subtle beat dragging or subtle pushes to the rhythm, all come over cleanly and clearly, and make musical sense in the context of each recording. Texture, timbre and tone is spot on.
Another little touch these speakers have is the chameleon-like ability to allow the room to "become" the venue in which the performance is happening. On the right recording, they are capable of transporting you right into the action. You get to hear studio walls, slap echoes off back walls, voices are given acoustic environments.
For example, on Dusty Springfield "The Look of Love" from the original Colgems, stereo vinyl of the soundtrack to the sixties David Niven Bond spoof "Casino Royale" the vocal booth can be heard. Dusty seems to be singing from a pan-pot positioned dry space, dead centre of the more wet Abbey Road acoustic of the orchestra and the Herb Alpert brass. All the time the subtle rhythmic device of a scraper purrs along hard left. Niiice
These speakers may not be everyone's cup of tea. Heavy rock afficionados may find the slightly distant perspective, these speakers produce, not quite in 'yer face enough. They will play rock with great dynamics and big tone, but that nth degree of oomph may be lacking for some listeners. I like tone and harmonics over ultimate welly, but others will differ in their preferences, which is fine. We don't all like the same thing, and speakers are highly subjective at the best of times.
Big classical works come over very well, as does choral, opera, chamber music, early music, jazz, blues, soul, fifties rock n roll, sixties pop, singer/songwriter country, bluegrass, big band swing, Latin, and electronic of both the Klaus Schulze/TD and Orbital persuasions.
The OmniMets have taken up permanent residence in the system now.
Anyone done/simmed a metronome for the Alpair 7p?
Specs at link:
https://www.madisoundspeakerstore.com/images/Alpair-7P-Gen1-specs.jpg
Specs at link:
https://www.madisoundspeakerstore.com/images/Alpair-7P-Gen1-specs.jpg
My experience with Metronomes, and BIBs for that matter is limited to one example of each, at one of Dave's events well over 10yrs ago, so I'd not be the best to comment on their sonic merits vis a vis other designs.
Aesthetics is a big issue casa Susan, so after 45yrs of silliness, any of the larger or more unconventional enclosures, or those with larger footprint demands such as FHs are a non-starter. This is where MLTLs / Pensils have a big advantage.
Aesthetics is a big issue casa Susan, so after 45yrs of silliness, any of the larger or more unconventional enclosures, or those with larger footprint demands such as FHs are a non-starter. This is where MLTLs / Pensils have a big advantage.
Why not consider GM's input and dimensions as on opportunity to hone your speaker design skills?
He practical gave you everything you need to design the enclosure, you just need to derive dimensions for top and base...
Sadly, after ~ two decades of having to deal with the metric system, I still manage to screw up some conversions when I'm in a time 'crunch', which nowadays is pretty much all the time
.Seeing Scott's dims made me realize I mixed some imperial dims with metric, so one more time:
Hmm, a quick sim where Vb = 10*~Vas, Fb = ~0.707*Fs:
L = 199 cm
W x D top = 81 cm^2
W x D base = 550 cm^2
Driver offset = 111.74 cm
vent = 12.56 cm^2 [~1.56" dia.] x ~1.9 cm [baffle thickness]
All dims inside [i.d.] and approximate.
Damp to 'taste'.
Sims nominally flat to ~42 Hz, so can only handle a few watts down low, but a stereo pair should make it enough based on how little power most folks here apparently need, especially if near/at a corner.
GM
I could, but different folks often prefer different WxD dims either to fit a room space or just what ratio is most pleasing to the eye, so as long as it's not such a high aspect ratio [wide/thin] that the driver is too close to the back wall, it can be whatever you want, though being a conical expanding pipe, square is the most common.
Not sure what in particular you want to understand, but this particular speaker alignment is a vented [mass loaded] 1/2 WL transmission line [conical TL], which it and pretty much all the other TL variants including back load horns [BLH] are explained in great detail here [lots of higher math, but not necessary to learn all a DIYer needs to know about designing them]: Quarter Wavelength Loudspeaker Design
GM