Lab Muzak system

What type of alignment would you choose for Alpair 5

  • Sealed 2.5 litres

    Votes: 1 33.3%
  • Vented 2.5 litres

    Votes: 2 66.7%
  • Some other alignment

    Votes: 0 0.0%
  • Don't bother using them in a lab they're too delicate :)

    Votes: 0 0.0%

  • Total voters
  • Poll closed .
Haha Gotta love the cold hard mathematicians


The point of this is quick and "it'll do" (how much time my colleagues will appreciate me dedicating to my lab stereo being of similar significance to WAF :))

In 2.5L sealed, I get f3 at ~104Hz
In 2.5L vented, a much lower f3. Probably a 20mm dia. Vent, 20-30mm length. Fb of about 100Hz or lower to tame the high Q Chebyshev rolloff.

A BLH is interesting, I wonder though, the Q is ~ 0.7 I would have thought maybe too high?

Saying that it's too high for Vented as well, but it can be used to warm up the bass at the expense of peak group delay.

The sealed gives around 1-2 db lift before cut off, so a small built in BSC.

The amp is 5 watts at a push, TDA2004 IC, salvaged PC PSU and cdrom :)

Once I get back home and sort the PC out I'll post some graphs for those that wish (hdd failurE, bsod, a week to get it usable again)
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Sealed F3 around 110-120 Hz (at a push)

Listening area is around 20ft x 65ft, sheet steel walls, in a machine room. So loud enough to hear it, but not so loud that in combination with ambient levels I damage my hearing :)

Currently I'm using pc speakers with retrofitted FRS5X, probably 2 watts amplifier as it uses the USB supply.

So in short, louder than those, and better bass response (although I maintain the FRS are ok fullrange up to a couple of watts, and I like their character. Not high end but "that'll do" in the given space and usage.