See above re enclosure size, since both Dave and I have already said they'll go into roughly the same size cabinet (16 litres). Likewise tuning has also been noted. 'Distortion' depends on what you mean by 'distortion' since there are a large variety of different types. In practice, not much in it in terms of response linearity, with the 12 having greater headroom. Ditto for off-axis response; very little in it, the 12 arguably (despite being larger) has slightly greater dispersion due to the cone profile.
Not necessarily. Depends what you're doing with them & where they're placed. Near a boundary, then no, they get sufficient help from the room, although a high output impedance amplifier (which is what it was assumed they'd be used with, though it's not mandatory) helps.
With the material you mention above, I don't see much issue with either the 10P or 12P (note that multiway speakers do not have to be biamplified. Most are not). Personally I'd use the 12P, but that says more about me than the drivers, and at a very small level, there's a little of me in that driver so I'm naturally a little biased. Imaging up to a point is a function of the recording, though the speaker / room has much to do with it also. Again, not much in it, but it's not comparing like with like since they're dissimilar sized units.
Sensitivity isn't too great an issue (solid state all the way for me). What I'm really after is low distortion with little breakup, as little off axis response deviation as possible and as flat on axis response as possible. I know I'm asking a bit much here!
Again, depends what you mean by distortion. For the others, you're asking a bit much because it's an engineering impossibility in this physical reality. I don't think you quite understand how loudspeaker drive units function. Taking widebanders, the majority of the BW they reproduce is via 'breakup' aka resonance of the cone substrate -how well depending on the level of control, and also the amount of self-damping in the cone (you can go too far on the latter score). A linear (or reasonably linear) HF response off-axis can be created via engineering a lift into the on-axis HF response. If a widebander over about 3in has a flat on-axis amplitude response, it will fall away off-axis -how quickly depending on cone profile. Which is not to say many conventional dome tweeters are all that much better on this score -because they aren't. Some are.
Since I suspect you'll always be panicking about some feature or other, I would concur with Chris's suggestion. Re Zaph's site however, as far as I know, the only Fostex and MA units there are the long-defunct FE166ES-R, FF165K and Alpair 6.
Late to join the campfire chat, but the title of this thread includes the word "compact" - though I can't recall seeing and even approximate expression of what dimensions you mean by that. AFAIC, that's a pretty important factor in preparation of a short list of candidates for the position.
While I've owned / built dozens of pairs over the year, I'm less drawn these days to bookshelf/standmounters for "serious" listening - fine for near field / computer monitors etc (such as listening to You-tube videos of other folks' systems), but many have limitations that if I remember my son's "student days", the system would often be to asked to exceed, And once stands are involved, the total cost of materials and floorspace may be the same. That last point is one of my personal hobbyhorses.
I'm as big a fan of the A10P as anyone here, I think, but Bob's suggestion of the FF165WK should also on that list, and if very compact size is required, perhaps even the step down size class should be considered.
While I've owned / built dozens of pairs over the year, I'm less drawn these days to bookshelf/standmounters for "serious" listening - fine for near field / computer monitors etc (such as listening to You-tube videos of other folks' systems
), but many have limitations that if I remember my son's "student days", the system would often be to asked to exceed, And once stands are involved, the total cost of materials and floorspace may be the same. That last point is one of my personal hobbyhorses.I'm as big a fan of the A10P as anyone here, I think, but Bob's suggestion of the FF165WK should also on that list, and if very compact size is required, perhaps even the step down size class should be considered.
Thanks for the responses, can anyone recommend a good cabinet for the 12P?
I really want to build my own, but thanks for the links to the Behringers - sort of defeats the DIY part. I just like the aesthetic of one driver without a crossover .
I'm always panicking about specs with everything so I think I've given the wrong impression here. Qes and Qts values on the 12P are slightly lower than the 10P, does this mean a shorter port is to be used? As far as dimensions go I have limited space depth wise.
As far as output impedance goes for step correction (if at all necessary) what sort of value is optimum. Is a simple Eq a better option? (I have similar tone controls with variable lift/frequency as DS's Precision Preamplifier). I know I'm being really pedantic here .
I really want to build my own, but thanks for the links to the Behringers - sort of defeats the DIY part. I just like the aesthetic of one driver without a crossover
.I'm always panicking about specs with everything so I think I've given the wrong impression here. Qes and Qts values on the 12P are slightly lower than the 10P, does this mean a shorter port is to be used? As far as dimensions go I have limited space depth wise.
As far as output impedance goes for step correction (if at all necessary) what sort of value is optimum. Is a simple Eq a better option? (I have similar tone controls with variable lift/frequency as DS's Precision Preamplifier). I know I'm being really pedantic here
.
While i totally agree that distortion in the larger sense is undesirable, but the only scientific study done, has shown that the distortion that we measure is meaningless unless quite large (IIRC 25% was the figure presented).
Note: althou done by a very copetent scientist no one has yet tried to duplicate his results.
You are obsessing way to much on numbers & graphs. You will need to just buy something and get going to establish a reference.
I find that the A10p (and the A10.3) give up a bit of dynamics to the A12p for lower bass, more extended top, and most importantly greater DDR. That means they can produce a better image/soundstage (if on the recording) and detail of voices/instruments. Of course one has to have a front end that also has good DDR or it all gets buried before it even gets to the speaker.
dave
Right, context = king.
No argument, my point was simply that 'distortion' as a term can cover a multitude of different things, e.g. HD, edge diffraction et al, so it depends what specifically you're talking about / referring to at the time.
I like the 12P for its additional macro & micro dynamic range, particularly their reaction time / handling of leading edges. Reminds me of electrostatics in that sense.
No argument, my point was simply that 'distortion' as a term can cover a multitude of different things, e.g. HD, edge diffraction et al, so it depends what specifically you're talking about / referring to at the time.
I like the 12P for its additional macro & micro dynamic range, particularly their reaction time / handling of leading edges. Reminds me of electrostatics in that sense.
OK I've been experimenting putting some shoe boxes on my desk . Height must be no more than 50cm, depth no more than about 30 and width no more than 30. The room is about 4m each way. The speakers themselves will be very close (read a few inches) from a wall, so maybe front ported is best?
My front end is very good, audio circuitry is one of the things I do well. I have switchable EQ on preamp so could have a flat setting for near field and a slight bass boost for far field. I keep my resistor values as low as possible to get the best noise performance and use low distortion op-amps (LME49720), the preamp has a low noise active volume control.
If someone gives me a link to a good enclosure for the 12Ps (I think they match my needs better than the 10s from what you guys are saying), then I could get building in a couple of weeks! No point fretting over minor details any longer .
. Height must be no more than 50cm, depth no more than about 30 and width no more than 30. The room is about 4m each way. The speakers themselves will be very close (read a few inches) from a wall, so maybe front ported is best?My front end is very good, audio circuitry is one of the things I do well. I have switchable EQ on preamp so could have a flat setting for near field and a slight bass boost for far field. I keep my resistor values as low as possible to get the best noise performance and use low distortion op-amps (LME49720), the preamp has a low noise active volume control.
If someone gives me a link to a good enclosure for the 12Ps (I think they match my needs better than the 10s from what you guys are saying), then I could get building in a couple of weeks! No point fretting over minor details any longer
.
Given 18mm plywood that gives a gross internal volume of about 32 litres, you only need half that. figure a 16 litre (net, get out a set of irrational numbers) box and put a 3" (76mm) vent about 224 mm long.
dave
Right, so the golden ration enclosure for the 10s has an internal volume of 16 litres but does not have the depth for a 224mm port as it's only 157mm deep internally .
Scott's enclosure for the 10s has an internal depth of 229mm and just enough width to mount the 12P on the baffle, but the 224mm port will be only 5mm away from the back of the enclosure.
Perhaps a narrower port can be used, ideally the speakers are better suited to my space requirements being wider than they are deep, but I'm guessing changing the dimensions but keeping the same internal area will create issues.
I remember reading that if a port is too long then a passive radiator can be used, any thoughts?
.Scott's enclosure for the 10s has an internal depth of 229mm and just enough width to mount the 12P on the baffle, but the 224mm port will be only 5mm away from the back of the enclosure.
Perhaps a narrower port can be used, ideally the speakers are better suited to my space requirements being wider than they are deep, but I'm guessing changing the dimensions but keeping the same internal area will create issues.
I remember reading that if a port is too long then a passive radiator can be used, any thoughts?
Right, so the golden ration enclosure for the 10s has an internal volume of 16 litres but does not have the depth for a 224mm port as it's only 157mm deep internally
Scott's enclosure for the 10s has an internal depth of 229mm and just enough width to mount the 12P on the baffle, but the 224mm port will be only 5mm away from the back of the enclosure.
You have a specific requirement. Except for keeping away from dimensions that are integer multiples of each other, not making one dimension significant ly longer, and making sure the baffle is wide enuff to fit the driver with some breathing room the actual shape is not all that important. Come up with a shape that works for you.
The vent can be made smaller, bent, or unload it out the top or bottom if the depth is insufficient.
dave
The room being 4m each direction = 16m^2 or approx 172ft^, is small enough that you might well be satisfied with a smaller driver than certainly the 12, or perhaps even either of the 10s.
Ports can be folded, particularly if fabricated as narrow full width slots - many of Dave's designs incorporate that feature, and of the few test builds I've done with both, I've preferred the slots.
and yes, with close proximity to back wall front ports are likely most practical
Ports can be folded, particularly if fabricated as narrow full width slots - many of Dave's designs incorporate that feature, and of the few test builds I've done with both, I've preferred the slots.
and yes, with close proximity to back wall front ports are likely most practical
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The 12P box I designed a couple of years ago (drawing by Dave) is on the Madisound site: http://www.madisound.com/pdf/SmallReflexA122p-191012.pdf
How far up from the bottom would be ideal?
Also, if you'll forgive my ignorance, but earlier someone said not to allow any of the dimensions to be integer multiples of the others, but the box is cross-sectionally square looking down. Is there any reason for this?
Is bracing required if I use 19mm ply?
Thanks again.
Also, if you'll forgive my ignorance, but earlier someone said not to allow any of the dimensions to be integer multiples of the others, but the box is cross-sectionally square looking down. Is there any reason for this?
Is bracing required if I use 19mm ply?
Thanks again.
Wherever you feel it fits best, it won't make a significant difference to the alignment.
Yes. Bluntly, I didn't give a hoot.
I needed a small standmount & I dislike shallow boxes of small proportions. A square cross section is OK providing it's not over-large and properly damped. The horizontal eigenmode is up about 790Hz which isn't difficult to kill. Where you run into problems is in larger cabinets, where the standing waves are at a lower frequency & consequently harder to damp out. This cabinet is not the last word, it's a simple BR. But perhaps a deceptively simple one, since as designed & near boundaries in the smaller / modest spaces I had in mind for it, it does work very nicely indeed. Dave & Chris's most excellent marKen's will be a little more refined, but this doesn't do a bad job at all for a simple box. I rather like it. I'd be inclined to add one (wherever you wish). Doubling the front baffle would be useful.
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Ideally yes. 19mm? Where do you get that? Acctually ply is very rarely exactly as named, cutting plans always need adjustment for the actual material thickness you buy.
dave
Was looking at Wickes (British home depot, but a little more professional), it's actually 18mm. What sort is best? Hard or soft? Here are some of the pieces I'm looking at:
Plywood - Sheet Materials -Building Materials | Wickes
I don't really have the space for a double thickness front baffle. What would it benefit more from, a vertical brace or a double front baffle? What sort of hole ratio would you use.
I've worked out some dimensions that are a little friendly to my space requirements and add a little more room for that 50mm port on the front. 240W 400H 170D. Are these good internal values acoustically?
Plywood - Sheet Materials -Building Materials | Wickes
I don't really have the space for a double thickness front baffle. What would it benefit more from, a vertical brace or a double front baffle? What sort of hole ratio would you use.
I've worked out some dimensions that are a little friendly to my space requirements and add a little more room for that 50mm port on the front. 240W 400H 170D. Are these good internal values acoustically?
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