Mine is not a pencil, it's an own design wich is wider and deeper than a pensil, and not that tall. A pensil does not go that low. It's also not a TL, but a classic ported box with the port on the back so i can load it on walls (wich i actually don't do than the bass gets to heavy, heavier than i expected). It's also not stuffed like a TL, only the top is slightly stuffed with fiberglass.
https://www.instagram.com/p/xPXRVUGp9T/
This is the not finished version of it. Some minor adjustments needed to be done (corner protection, details in painting, ...)
And the Alpair 10.3 is a single cone full range copper membrane driver, not dual cone or coaxial driver.
And i did hear tunes i mixed on hi power dub sound systems (scoops and so) and Turbosound rigs so i know how they sound on hi volume level on multiway speakers.
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Hmm, I didn't think you were running pensils, which is why I was a little startled at some of the assertions made in the post I quoted.
Actually, to be really picky 😉 the copper is just anodising. The cone itself is an aluminium/magnesium alloy AFAIK.
Actually, to be really picky 😉 the copper is just anodising. The cone itself is an aluminium/magnesium alloy AFAIK.
The short answer is 'because I didn't have the same design objectives'. 😉
The longer one, which I've described a few times on various threads, goes something like this.
The primary design goals were:
1/ To be as physically simple to build as possible
2/ To be easily tuned to suit room / system / taste requirements via varying the damping alone
3/ To provide relatively (for a non-horn type) broadband gain in a quasi pro-audio alignment which would help compensate for step-loss once room gain &c. were accounted for. This also helps with a lot of rock music etc., where the majority of the LF energy exists in the ~60Hz - 120Hz region
4/ To have an essentially unreactive impedance load (TL style) which is beneficial with typical SET amps in particular. This goes hand-in-hand with very linear excursion behaviour through (and below) their main operating BW.
All of those mandate a higher tuning frequency than might otherwise have been the case and a large, acoustically efficient box. The basic alignments (I have two) are closed form; one is based on T/S filter theory, the other on earlier design methodologies. Both work in more or less the same way and produce alignments with similar general characteristics, but they differ in detail. Anyway, that's why they are the way they are. I could create smaller MLTLs that are tuned lower, but Bob and Jim both have excellent examples of those for the MA drivers & others, so I'm happy to waffle off and plough a slightly different furrow.
The longer one, which I've described a few times on various threads, goes something like this.
The primary design goals were:
1/ To be as physically simple to build as possible
2/ To be easily tuned to suit room / system / taste requirements via varying the damping alone
3/ To provide relatively (for a non-horn type) broadband gain in a quasi pro-audio alignment which would help compensate for step-loss once room gain &c. were accounted for. This also helps with a lot of rock music etc., where the majority of the LF energy exists in the ~60Hz - 120Hz region
4/ To have an essentially unreactive impedance load (TL style) which is beneficial with typical SET amps in particular. This goes hand-in-hand with very linear excursion behaviour through (and below) their main operating BW.
All of those mandate a higher tuning frequency than might otherwise have been the case and a large, acoustically efficient box. The basic alignments (I have two) are closed form; one is based on T/S filter theory, the other on earlier design methodologies. Both work in more or less the same way and produce alignments with similar general characteristics, but they differ in detail. Anyway, that's why they are the way they are. I could create smaller MLTLs that are tuned lower, but Bob and Jim both have excellent examples of those for the MA drivers & others, so I'm happy to waffle off and plough a slightly different furrow.
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Gasp ! Those are clearly Not.. cheap Chinese drivers.
If Papa uses/considers them, there's Fair chance they may even work well 😉
If Papa uses/considers them, there's Fair chance they may even work well 😉
Shoot me down in flames if this is a stupid idea but.......
With a fullrange driver sometimes one needs to prop up the bottom end with a subwoofer for the really deep bass for different music or HT use. Usually a subwoofer has a plate amp that can vary the frequency cut-off, a gain control and a phase control; so if your fullrange driver needs a little lift at the top end with a dedicated tweeter why not adopt the same principle and have an amp that can dial-in the upper frequency cut-off point to suit taste, program material, room conditions, driver abilities etc.
Never heard of it being done. Tweeters seem only to be added with a simple passive crossover to a fullrange driver.
Controls could be frequency, slope, and gain and generally to operate above 10kHz (approx)
as most,if not all, fullrange drivers are good to that point.
Just a thought!
With a fullrange driver sometimes one needs to prop up the bottom end with a subwoofer for the really deep bass for different music or HT use. Usually a subwoofer has a plate amp that can vary the frequency cut-off, a gain control and a phase control; so if your fullrange driver needs a little lift at the top end with a dedicated tweeter why not adopt the same principle and have an amp that can dial-in the upper frequency cut-off point to suit taste, program material, room conditions, driver abilities etc.
Never heard of it being done. Tweeters seem only to be added with a simple passive crossover to a fullrange driver.
Controls could be frequency, slope, and gain and generally to operate above 10kHz (approx)
as most,if not all, fullrange drivers are good to that point.
Just a thought!
MiniDsp 2way plate amplifiers for active monitors will allow for both a dedicated HP and LP to the fullrange and sub and also allow for filtering and eQing the response of he fullrange to taste. Not exactly a cheap option though but certainly the most simplistic and best outcome for a FAST speaker. If you can feed the plate amp a digital signal, you skip yet another harmful A-D conversion stage singe the amps are IceD they work via i2S simplifying the signal chain to the likes of NAD M series components.
The important thing to remember is to use the smallest fullrange driver possible as NOTHING can combat poor off axis response as it relates to radiating surface. A 3" driver begins to rolloff terribly above 6khz which is what accounts for the perceived lack of high end even slightly off axis. The ideal driver for a FAST might just be the B&G Neo8 mid-tweeter in all instances.
You 'could' actually wire in a small tweeter with a 2nd order HP only if you can match efficiency but having to add an LPad kinda defeats the purpose of fullrange sans passive components which many believe suck the life out of these type systems. I'd keep it as simple as possible personally and choose a full range with a rising response above 10khz such as that from Celestion.
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Hi Scott, thanks for the clarification, you put in a lot of consideration into the design, what other reasons motivated you to cutoff the LF higher?
Hi Waxx, thanks too for the clarification, nice design, do you find the bass deep or hollow?
You may also want to checkout this http://www.diyaudio.com/forums/multi-way/300452-dancehall-gemstone.html#post4911660
Hi Waxx, thanks too for the clarification, nice design, do you find the bass deep or hollow?
You may also want to checkout this http://www.diyaudio.com/forums/multi-way/300452-dancehall-gemstone.html#post4911660
Unless perhaps we're talking Voxativ full-range drivers.
14.900 $ for a matched pair better not have even traces of midrange shout and a ruler flat response,
and for such a ridicoulus price you'd expect them to sound even better than very large ELS's.
Voxativ's flagship driver is so expensive it doesn't even have a price tag.
I would expect that they cure cancer as an added bonus.
Usually, the more you pay, the less you get to see, measurement wise 😀
I'm doing 17 Hz - 18 KHz, with the same driver, not a single one though.
I'm doing 17 Hz - 18 KHz, with the same driver, not a single one though.
Can't argue, although Feastrex were even 'worse' on that front: not a single measurement or statement of specification for any product, ever, although I recall a useful comment that the sound of a particular model was 'simply scrumptious.' At which point I strung myself up, and have since been posting as a ghost. I'm not sure whether Feastrex are still in business as I understand (although I speak under correction) that the designer left the company. If memory serves, their top price model as of a few years ago was about $70,000, give or take.
Maybe Clark can chime in with his annual Christmas card re Feastrex?
http://www.diyaudio.com/forums/feastrex/283722-update-my-own-journey-feastrex.html
http://www.diyaudio.com/forums/feastrex/283722-update-my-own-journey-feastrex.html
You're welcome.
Aren't those four enough? 😉 Humour aside though, nothing significant. The four points I listed, when combined, require the high[er] nominal FB compared to most other MLTL variations. That said, depending on damping etc., they do get a fair bit lower than the nominal. I haven't had any complaints (or can't recall any) about lack of output once people have tweaked the damping to suit their particular requirements, so presumably the balance has been felt to be a reasonable one. YMMV as ever of course.
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It would be interesting. Last time I looked at his site he had some Feastrex related projects in the works, so be good to know how he's getting on.
I just heard a Feastrex at a friends place, while the treble are nice and sparkly. The mid and low leaves a lot to be desired. We compare it with a Coral Holey in a small TL and I though the sound was more completed and I prefer the sound of the Holey more. I had those holey in TL for several weeks at my home and I prefer my 2-way LS50. So in the end it depends on tastes.
I also own Fostex Fe108 SOL and a Scanspeak 10F/8414, we'll see how that goes.
Hi mayhem13,
I know the minidsp is very capable but it is not really the route that I want to go down, on grounds of both cost and complexity. A much simpler solution for me would be what I outlined. There are some simple pcb boards from the far east that offer basic subwoofer controls for an amp. that could I guess be adapted to change the frequency response to suit tweeter duty by changing relevant components. Not sure how to go about that. I'll have to give it some study and consideration.
Cheers
I know the minidsp is very capable but it is not really the route that I want to go down, on grounds of both cost and complexity. A much simpler solution for me would be what I outlined. There are some simple pcb boards from the far east that offer basic subwoofer controls for an amp. that could I guess be adapted to change the frequency response to suit tweeter duty by changing relevant components. Not sure how to go about that. I'll have to give it some study and consideration.
Cheers
The way speakers are measured results in Full ranges having very appealing curves, but playing different genres of music reveals other nuances in the speaker design, the simplicity of full range design means it has fewer mistakes especially if you throw it in a stuffed closed box, conditioning may also play a role on how you expect the speaker to sound, curves aside
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