Hello Sarathssca, (Guys)
Of possible and practical interest to you:
The Alpair 7P was developed both as a single driver and to work in conjunction with the Alpair 12PW:
http://www.diyaudio.com/forums/markaudio/260714-alpair-7p-alpair-12pw-combination.html
For any small driver, if you're in need of large bass, adding a woofer is an option that should be considered. Both Alpair 7's are bass capable in a larger box (Pensils for example) within sensible reason. Much depends on personal musical taste. Are you the sort of fella listening to "rock" or are you into "easy vocal" etc etc. Think about your listening needs in terms of the music you like and the volume you want when listening.
Cone design is extremely complex, especially in a full-range unit. The cone emitting surface and its substrate material have to both oscillate and resonate in collective action. For mechanical oscillation - LF generation, the cone (and the rest of the driver's power-train - coil and suspensions) must be of a sufficient mass and material type to withstand the maximum design driven load. However, for semi static and static resonance - HF generation, the cone and power-train's mass must be small to overcome losses in in the minimal section of the power conversion band. Added into the mix is the flex/stress ratio and the property of a material's surface and substrate to transmit mechanical energy in a pattern......So what this means:
Metal has heavier mass than paper, flex ratio is lower (wobbles and deforms more easily) but its load transmission losses are better than paper (more efficient in HF).
Paper has lighter mass than metal, flex ratio is higher (more stiff due to the weaves of paper and glass fibre in our case) but the transmission losses are greater, it looses the HF sooner than metal.
As a design/Mech Eng., I can't say which "sounds better", thats a matter of personal taste. What I try to do is listen to what guys tell me, go on to my work bench and think how to do it, come back and report, then make.
Most of the regular members will be able to give you their listening impressions while I try my best to explain but bear my background in mind, my brain is constantly churning away in a mechanical/electro world.
Hope this helps.
Thanks
Mark.
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I concur with Bill's opinion. I have a pair of A7P's that are undergoing my break-in process -- they are my HT mains at the moment. After about a month of soap operas and network serials, they still seem to be the brightest of the Alpair's I have owned. This weekend, I hope to put them in my 2-channel for some serious comparison. Stand by.
Bob
A lot of subs do not go high enuff to blend well.
This statement can be gerneralized.If you follow Geddes & Toole, any satelitte onlt need reach 80 Hz, and the lowesr 2 octaves require multiple woofers appriately placed thuout the room.
The 1st comment out of most people who hear FH3 is, "hoe can that 4" produce so much bass" They won't reproduce an earthquake, but do produce quite satisfying bass. FHXL takes you a bit lower.
dave
definitely. Subs shouldnt go as high as 80 hz I think. Or if you need to, its the real maximum and id like to use at least 4th order to try to make the sub inaudible.
when I used stereo subs, 80 hz was too high imo and Ive never liked the blending. Now, maybe its I didnt knew exactly how to integrate my subs back then, but woofers are prefered if you go as high as 80hz...
ive found that to integrate properly a sub, you need to look at least at the f6 of the mains and set the xo around there. my continuum has a f6 of 56hz, and Ive found the ebst result setting my sub at a 49hz XO 6th order. integration is perfect like that!
BUT still, the midbass of a small woofer has never been good enough for me.
I might try the next logical step: 15inch from 30hz to 200hz then use the MA7p for upward.
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80 Hz is the nominal frequency that Toole & Geddes specify to XOing to multiple mono woofer.
Woofers when you are trying try to integrate to FRs should go much higher.
dave
everybody has a different definition of midbass lol. I should just have said the actual bass notes, which are around 70hz to 200hz.. I always prefered bigger woofer for that part of the spectrum. I think the thump live around 80 to 140 hz, and a small woofer will always suffer.
Not true, they are well defined. You are just misusing the term. To repeat the definitions:
20-40 low bass
40-80 midbass
80-160 upper bass
160-320 lower mids
320-640 mids
640-1.25k mids
1.25k-2.5k upper mids
2.5k-5k lower treble
5k-10k treble
10k-20k upper treble
dave
Up through college, I played flute and oboe and dabbled with clarinet. After that, I could not find the time to maintain an embouchure, so I switched to recorder. At one time I owned a complete recorder corsort bass through soparino.
Pretty much what I said. The highest fundamental of the piccolo is 4186Hz. The grand staff is divided by middle C -262Hz in modern tuning. The first line below the treble staff is the same as the first line above the bass staff. BTW, this is how I divide my FAST system. The XO is set at 200. I think I will move the XO up to 262 just because. That shouldn't affect the sound much.
Further OT: It you choose a tuning of A=432 rather than A=440, the notes "C" become the binary series. A bit obsessive/compulsive, but J. S. Bach noted this a few years ago.
Not really, and of course it is! So much of what gets written on these forums is about listening to the equipment. In the end I could care less what equipment I am using, so long as the music is enjoyable. And, one's enjoyment of music is helped a lot by knowing a bit of music theory.
Bob
Hello ,
Finally I have ordered a pair of alpair 7p... Not very sure if its the better option .. Gone by the good reviews of the metal version 7.3 and expecting the paper version would be equally good too and it's having better sensitivity ... Thought it would be enough for 15x9 sq feet room , but not sure its true till I build the complete system - suitable cabinet and amplifier ... Also it's my first such diy build ...
Thanks for the inputs and suggestions
Regards
S Sarath
Finally I have ordered a pair of alpair 7p... Not very sure if its the better option .. Gone by the good reviews of the metal version 7.3 and expecting the paper version would be equally good too and it's having better sensitivity ... Thought it would be enough for 15x9 sq feet room , but not sure its true till I build the complete system - suitable cabinet and amplifier ... Also it's my first such diy build ...
Thanks for the inputs and suggestions
Regards
S Sarath
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