Pensils for Alpair 10.3 & Alpair 10p

Scott, Are there any ill side effects to increasing the overall height of your pensil designs and raising the port higher off the ground? I would maintain all internal dimensions and spacing, just add a cavity to the bottom.
Also do you expect the pensil's to significantly outperform your Standmount Bass Reflex designs? (apart from bass) Thx!
 
They're different to the BR stand mounts. I can't really comment on whether they'll outperform them or not, since the design remits are not the same. There's more adjustability & a flatter impedance load with the pensils, along with more useable LF extension, although Fb isn't actually all that far removed. Depends on what it is you're trying to do as to which is likely to meet your requirements.

The 10.3 & 10P box are already taller than their predecessors. If you raise them further, you'll loose out on floor-coupling and probably end up with more of an issue with floor-bounce, so I not something I'd recommend.

Best
Scott
 
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Are there any plans to redesign the Frugal-Horn 3 to accept the 10.3 or would it work to simply upscale the dimensions of the FH3 to keep in scale with the larger driver? I know very little about speaker design, but I suspect that simply up scaling won't provide optimal performance.
 
Scaling boxes rarely works unless you know exactly what it is you're doing, since it is not simply a case of increasing dimensions in an arbitrary fashion. To scale a box, you need to know what the design objectives of the original were, then re-size the enclosure to based on these and the altered target alignment.

A box similar to FH3 has been done, as seen in the other thread. http://www.diyaudio.com/forums/markaudio/239793-comparing-three-different-alpairs.html#post3577037 It is currently being prototyped.
 
FHXL/10Ps have been playing in 2.0(no woofers) in my HT rig for this past week - working the drivers in as much as possible.

My son plays bass in a local band and recently gave me a copy of their soon to be released first CD - material with which he'll of course be intimately familiar, and I've heard them play live a couple of times as well. While these won't cleanly deliver stage level full output of the bottom string, they have substantially better bass than they have any right to.

edit: let me rephrase that - Scott would say they should meet their design remit without compromise - it's still hard to believe how much these little cones can emit

Dave has the Pensil10.3s at his place - perhaps he'll pipe in with some observations.
 
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The pensil is coming on :)
 

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Pensil for 10.3 built 1/2 inch too thin.

Hello out there:

I'm somewhat of a newbie and I'm at the glue-up phase of my Alpair 10.3 Pensils. I just realized that I mistakenly made the enclosure 9 inches wide instead of 9.5 inches wide. All other dimensions are OK. Have I made an irrecoverable mistake? One cabinet has already been glued together. Are my enclosures now trash/firewood? Thanks,

--Mel
 
Thanks much for your quick reply! The more I think about my my woodworking mistake, the more I realize that my error is similar to adding heavy bracing w/o increasing the enclosure dimensions to compensate for the lost internal volume. I bet lots of folks have made that mistake.

All the best,

--Mel